Transmissible Spongiform Encephalopathy Infectivity in Blood and Other Biologicals: Strategies for Detection, Decontamination and Removal FDA 2024
Content current as of: 03/26/2024
Regulated Product(s) Biologics
Principal Investigator: Luisa Gregori, PhD Office / Division / Lab: OBRR / DETTD / LBTSEA
General Overview
Creutzfeldt-Jakob disease (CJD) and its variant form (vCJD) are rare, fatal, brain diseases known as transmissible spongiform encephalopathies (TSEs), or prion diseases. The term "spongiform" refers to the appearance of holes in the affected brain tissue, resembling a sponge, when observed under the microscope. In cows, a similar disease is popularly called "mad cow disease." Consumption of beef from cattle infected with mad cow disease caused the appearance of vCJD in humans.
TSEs are particularly insidious infections because the agents that cause them can remain undetected for decades, causing no noticeable illness. These agents are not like viruses and bacteria and they resist standard decontamination procedures. In addition, there are no tests that identify individuals who have CJD or vCJD before disease becomes apparent. As a consequence, these agents have on rare occasions been transmitted through corneal or neural tissue transplantations, blood transfusions, contaminated neurosurgical instruments or by treatment with plasma-derived products or drugs made from infected tissues (such as human pituitary-derived growth hormones).
vCJD is of particular concern because affected individuals can have the TSE agent in their blood for years before there are any signs of infection. In the meantime, these individuals represent a potential source of vCJD infection risk if they donate blood for transfusion.
Four transfusion-transmitted vCJD infections have already been reported in the United Kingdom (UK). One additional infection attributed to treatment with a protein called coagulation Factor VIII that was obtained from vCJD-contaminated human plasma and used to treat a patient with hemophilia. The number of silently infected blood donors in the UK is unknown, but estimates range from a few hundred to several thousand.
To reduce the risk of transmitting vCJD by blood and other biological sources, FDA has recommended deferring people who are at high risk for CJD and vCJD from donating blood and tissues. The deferral policies are based on the theoretical risk posed by eating contaminated beef. Individuals are deferred from donating blood if they have resided or traveled for a total of three or more months in the UK (the country with highest number of mad cow disease cases) between 1980 and 1996; or if they resided or traveled longer than 5 years from 1980 to the present in Western European countries. The recommendation is slightly different for plasma donations. Individuals are also deferred if they received blood transfusion in the UK from 1980 to present. In addition, permanent deferral is recommended for individuals who have been diagnosed with vCJD or other forms of CJD, individuals who received a high risk tissue transplant (e.g., cornea or neural tissue), and donors with one or more blood relatives diagnosed with CJD. While protecting the public from the risk of accidental exposure to the TSE agents, those policies have deferred many donors who are unlikely to have been infected with TSE agents and may have contributed to blood shortage in some cases. This situation could be improved if a TSE screening test is available to test donated blood for the presence of vCJD agents. FDA has also encouraged the development of such a test.
Several commercial companies are developing test methods to detect TSE. However, a major difficulty is lack of reference standards to validate the candidate tests; that is, there is no standard sample containing a known amount of vCJD agent against which to compare a new test to verify that it works properly. Our laboratory is trying to resolve this difficulty by producing infected animal blood as reference standards. We also developed new animal models of vCJD infection in order to study how TSE agents cause disease.
In addition, our laboratory is studying ways to reduce the risk of transmitting TSE agents that might be present in blood using a variety of devices, such as filters. A similar approach will be applied to remove other pathogens from blood as well. This investigation is highly critical to the FDA mission of protecting public health from the threat of blood-borne pathogens while maintaining an ample supply of blood.
Scientific Overview
While the risk of dietary vCJD transmissions has decreased, secondary transmissions of vCJD by blood transfusion remain the major threat to the blood supply and to public health. The newly reported case of transmission by Factor VIII derived from human plasma in the UK has broadened the risk to include soluble plasma products. An ante-mortem plasma-based vCJD test would offer a valuable tool for reducing this risk.
Our research program focuses on separate but complementary approaches to developing a TSE screening assay with the goal of enhancing the safety of blood and other biologics, reducing the risk of iatrogenic transmissions, and improving CJD diagnosis. These goals are highly relevant to the FDA mission to protect and improve public health. The research will also generate valuable material for studies of TSE transmission in transgenic mice and how the genetics of the animal host affects the pathology of TSE and the replication of the infectious agent.
Detection of TSE infectivity is currently conducted using PrPTSE (Amplification of pathological prion protein of transmissible spongiform encephalopathies) as a surrogate marker. Although there are reported cases in which the relationship between infectivity and PrPTSE is questionable, in most cases the presence of PrPTSE correlates with infectivity. Thus, in our studies, we use PrPTSE as biochemical marker of TSE infectivity, and when possible, infectivity is confirmed with the animal bioassay.
In previous studies, a test was developed in which PrPTSE was first captured using an immuno-affinity resin followed by detection with either a Western blot or an Origen Analyzer (an ELISA-like assay). FDA developed another assay format called DELFIA to detect PrPTSE in infected tissues. Both assay platforms are very sensitive and are currently available in the laboratory. However, PrPTSE concentrations in blood may be below the detection limit of both assays. Therefore, our program also envisions a different strategy to increase PrPTSE concentrations in blood using a relatively new technology called Protein Misfolding Cyclic Amplification (PMCA) which amplifies PrPTSE in vitro. This approach must be thoroughly investigated and demonstrated to have the necessary sensitivity and specificity. If successful, PMCA has the potential for detecting PrPTSE in infected blood.
Our laboratory is also developing vCJD-infected reference standard materials suitable for validating candidate TSE screening tests. We will titrate vCJD-infected blood using a panel of transgenic (Tg) mice expressing the human PrP gene ("humanized"Tg mice) and wild-type mice. We will test humanized Tg mice that over-express PrP and mice that do not over-express PrP. These mouse models must be experimentally evaluated and compared because mice sensitivity to low infectivity levels cannot be anticipated a priori. Control studies will be conducted to ensure that under the conditions tested the mice do not develop spontaneous neurological disease that could affect the results of the titrations.
Publications
Viruses 2023 Jun 28;15(7):1466 Kinetics of abnormal prion protein in blood of transgenic mice experimentally infected by multiple routes with the agent of variant Creutzfeldt-Jakob disease. Yakovleva O, Pilant T, Asher DM, Gregori L
J Gen Virol 2022 Jul;103(7):001764 Abnormal prion protein, infectivity and neurofilament light-chain in blood of macaques with experimental variant Creutzfeldt-Jakob disease. Yakovleva O, Bett C, Pilant T, Asher DM, Gregori L
Pathogens 2022 May 20;11(5):597 Experimental bovine spongiform encephalopathy in squirrel monkeys: the same complex proteinopathy appearing after very different incubation times. Piccardo P, Cervenak J, Goldmann W, Stewart P, Pomeroy KL, Gregori L, Yakovleva O, Asher DM
Transfusion 2021 Nov;61(11):3181-9 Effect of storage on survival of infectious Treponema pallidum spiked in whole blood and platelets. Tamrakar P, Bett C, Molano RD, Ayub A, Asher DM, Gregori L
Emerg Infect Dis 2020 Oct;26(10):2478-80 Eliminating spiked bovine spongiform encephalopathy agent activity from heparin. Bett C, Andrews O, Asher DM, Pilant T, Keire D, Gregori L
Biologicals 2020 Sep;67:56-61 Processing bovine intestinal mucosa to active heparin removes spiked BSE agent. Andrews O, Bett C, Shu Q, Kaelber N, Asher DM, Keire D, Gregori L
Pharmacoepidemiol Drug Saf 2020 May;29(5):575-81 Assessment of risk of variant Creutzfeldt-Jakob disease (vCJD) from use of bovine heparin. Huang Y, Forshee RA, Keire D, Lee S, Gregori L, Asher DM, Bett C, Niland B, Brubaker SA, Anderson SA, Yang H
PLoS One 2019 Dec 12;14(12):e0225904 Quaking-induced conversion of prion protein on a thermal mixer accelerates detection in brains infected with transmissible spongiform encephalopathy agents. Kaelber N, Bett C, Asher DM, Gregori L
Biotechniques 2018 Dec;65(6):331-8 Rapid selection of single-stranded DNA aptamers binding Staphylococcus epidermidis in platelet concentrates. Kaur SJ, Gilman V, Duong M, Asher DM, Gregori L
Handb Clin Neurol 2018;153:1-17 Human transmissible spongiform encephalopathies: historic view. Asher DM, Gregori L
J Gen Virol 2018 Mar;99(3):422-33 Both murine host and inoculum modulate expression of experimental variant Creutzfeldt-Jakob disease. Bett C, Piccardo P1, Cervenak J, Torres JM, Asher DM, Gregori L
AAPS J 2017 May;19(3):765-71 A heparin purification process removes spiked transmissible spongiform encephalopathy agent. Bett C, Grgac K, Long D, Karfunkle M, Keire DA, Asher DM, Gregori L
Transplantation 2017 Apr;101(4):e120-4 Rapid testing for Creutzfeldt-Jakob disease in donors of cornea. Gregori L, Serer A, McDowell KL, Cervenak J, Asher DM
Transfusion 2017 Apr;57(4):924-32 Geographic exposure risk of variant Creutzfeldt-Jakob disease in US blood donors: a risk-ranking model to evaluate alternative donor-deferral policies. Yang H, Huang Y, Gregori L, Asher DM, Bui T, Forshee RA, Anderson SA
Transfusion 2015 Feb;55(2):405-12 Blood reference materials from macaques infected with variant Creutzfeldt-Jakob disease agent. McDowell KL, Nag N, Franco Z, Bu M, Piccardo P, Cervenak J, Deslys JP, Comoy E, Asher DM, Gregori L
WITH Chronic Wasting Disease CWD TSE Prion in Cervids out of control in North America, the fact that science is on the verge of finally making the call on CWD being zoonotic to humans, the fact that CWD will easily transmit by blood, the fact that CWD transmission is far different than BSE and nvCJD risk factors, i have been very concerned with CWD transmission to humans, and the iatrogenic transmission there from, including blood, would be of grave concern. i would kindly like to point out a few of my concerns...terry
Bloodborne prions detected in healthy-appearing CWD-infected free-ranging white-tailed deer in several U.S. states
Amy V. Nalls1 *, Erin E. McNulty1 , Devon J. Trujillo1 , Nathaniel D. Denkers1 , Samantha K. Scherner1 , Ethan P. Barton2 , Christopher A. Cleveland3 , Natalie SLlwell3 , James M. Crum4 , Daniel M. Grove5 , Jeremy S. Dennison6 , Jennifer R. Ballard7 , Michael J. Chamberlain8 , Edward A. Hoover1 , Mark G. Ruder3 and Candace K. Mathiason1
1 Dept. of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
2 Game Management Services Unit, Wildlife Resources SecLon, West Virginia Division of Natural Resources, WV, USA
3 Southeastern CooperaLve Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
4 West Virginia Division of Natural Resources, Elkin, WV, USA
5 University of Tennessee Extension, Nashville, TN, USA
6 Tennessee Wildlife Resources Agency, Jackson, TN, USA
7 Arkansas Game and Fish Commission, LiUle Rock, AR, USA
8 Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, USA
Aims: The infecLous agent that iniLates prion infecLon has been demonstrated in the blood of humans, nonhuman primates, sheep and cervids. Yet, the development of rapid, sensiLve, and specific assays to detect prions in blood has been challenging due to presumed low concentraLons of hematogenous prions and/or inhibitors present in blood. We have capitalized on a unique and extensive repository of serially-collected blood samples from longitudinal CWD experimental studies in the naLve white-tailed deer (WTD) host, collected minutes post CWD exposure through terminal clinical CWD presentaLon, to demonstrate the presence of bloodborne prions by lipase iron-oxide bead RT-QuIC (LIQ). Here we aim to explore LIQ’s ability to detect prions in the blood of WTD naturally-exposed to CWD.
Materials and Methods: Field-collected blood samples from free-ranging WTD in CWD endemic areas of Arkansas, Tennessee and West Virginia were preserved in ACD tubes, held for 3-5 days at refrigerated temperatures and shipped to CSU. Buffy coat cells (BC) were extracted from each sample and processed by LIQ.
Results: We found that white blood cells rouLnely retain integrity for successful isolaLon acer several days held at refrigerated temperatures, and as liUle as 1mL of anLcoagulated whole blood contained sufficient BC for LIQ. In addiLon, this study reveals a correlaLon between the stage of CWD infecLon and prion detecLon in BC. We demonstrate prions in the blood of the majority of lymphoid posiLve deer (RAMALT 73%, tonsil 80%, and retropharyngeal 85%), and 100% of deer with CNS involvement.
Conclusions: We have opLmized the RT-QuIC assay to detect bloodborne prions using lipases and iron-oxide bead extracLon and have demonstrated detecLon of prions in blood collected in early to late-stage disease from both experimental and natural CWD-infected WTD. Future work will explore the potenLal of this assay in diagnosLcs and surveillance of addiLonal free-ranging cervid populaLons.
Funded by: MulLstate ConservaLon Grant Program, The AssociaLon of Fish and Wildlife Agencies and HHS NIH NIAID
Grant numbers: F20AP00172 and HHS NIH NIAID R01AI112956
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Early and Terminal Detection of Chronic Wasting Disease in Retropharyngeal Lymph Node Cell Subsets
Caitlyn Kraft1 , Joseph Westrich1 , Brianne Coleman1 , Edward Hoover1 , Candace Mathiason1
1 Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
Aims: Chronic Wasting Disease (CWD) is known to have significant lymphoreticular system involvement. The presence of prions in blood cell components of CWD infected cervids is detected as early as 15 minutes post inoculation (pi). Yet, the presence of prions within specific lymphoid tissue cell subsets remains relatively understudied. To gain better understanding of the peripheralization of blood-borne prions, we analyze specific retropharyngeal lymph nodes (RLN) cell populations during early and terminal CWD infection for their prion carrying capacity.
Materials and Methods: Early CWD infection: n=6 white-tailed deer (WTD) were intranasally-inoculated with 0.5 mg CWD+ brain. The deer were sacrificed at 1, 2, or 3 months pi (n=2 each) and RLN were collected. Terminal clinical CWD: n=8 WTD were orally inoculated with 10mg CWD+ brain (n= 4) or 10mg CWD+ brain bound to montmorillonite clay (n=4). CWD- inoculated deer were also sacrificed at each time point (n=5). Cell populations (B cells, CD4 T cells, and CD8 T cells) were magnetically separated from RLN, were confirmed/assessed for purity by flow cytometry, and analyzed for CWD status by Real Time Quaking Induced Conversion.
Results: At 1-month pi, all LN specific cell populations and whole RLN remained CWD- by RT-QuIC. At 2 and 3 months pi, prion detection was demonstrated in all RLN cell populations and whole dissociated RLN. Cell population data from clinical animals is currently being generated and will be included in poster results.
Conclusions: Our findings suggest that prions traffick within the blood to RLN between 1 and 2 months pi. Further assessment of blood and lymphoid cell subsets will contribute to our understanding of early intra-host prion trafficking and reveal the role of specific cell subset contributions to prion pathogenesis. Furthermore, these findings will enhance our ability to mitigate CWD and other protein misfolding disorders.
Funded by: NIH
Grant number: RO1-NS061902-09R, PO1-AI077774, R01-AI112956-06
Acknowledgements: We abundantly thank Sallie Dahmes at WASCO and David Osborn and Gino D’Angelo at the University of Georgia Warnell School of Forestry and Natural Resources for their long standing support of this work through provision of the hand-raised, CWD-free, white-tailed deer used in these studies.
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Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research
Title: Successful transmission of the chronic wasting disease (CWD) agent to white-tailed deer by intravenous blood transfusion
Author item MAMMADOVA, NAJIBA - Orise Fellow item CASSMAN, ERIC - Orise Fellow item Greenlee, Justin Submitted to: Research in Veterinary Science Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/14/2020 Publication Date: N/A
Citation: N/A Interpretive Summary: Chronic wasting disease (CWD) is a fatal disease of cervids that causes damaging changes in the brain. The infectious agent is an abnormal protein called a prion that has misfolded from its normal state. Chronic wasting disease may be transmitted from ingestion of prions shed in bodily fluids (e.g. feces, urine, saliva, placenta tissue) of infected animals. Few studies have also reported detection of infectious prions in blood. To determine if CWD-infected blood can transmit prion disease, recipient deer were inoculated intravenously (IV) with blood derived from a CWD-infected white-tailed deer. We found that two out of three animals developed disease. This study complements and supports an earlier finding that CWD can be transmitted to deer by intravenous blood transfusion from white-tailed deer with CWD. This information is useful to wildlife and agricultural officials that are involved in efforts to control the spread of chronic wasting disease.
Technical Abstract: Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSEs) that affects free-ranging and captive cervid species. The infectious agent of CWD may be transmitted from ingestion of prions shed in bodily fluids (e.g. feces, urine, saliva, placenta tissue) of infected animals, contaminated pastures, and/or decomposing carcasses from dead animals. Studies have also demonstrated prion infectivity in whole blood or blood fractions of CWD infected animals. To determine if CWD-infected blood contained sufficient levels of prion infectivity to cause disease, recipient deer were inoculated intravenously (IV) with blood derived from a CWD-infected white-tailed deer. We found that the CWD agent can be successfully transmitted to white-tailed deer by a single intravenous blood transfusion with a mean incubation period of approximately 35 months and an attack rate of 100%. This study complements and supports an earlier finding that CWD can be transmitted to deer by intravenous blood transfusion from white-tailed deer with CWD.
Successful transmission of the chronic wasting disease (CWD) agent to white-tailed deer by intravenous blood transfusion
Najiba Mammadovaa,b, Eric Cassmanna,b, Justin J. Greenleea,* aVirus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Avenue, Ames, IA 50010, USA bOak Ridge Institute for Science and Education (ORISE), USA ARTICLE
INFO Keywords: Blood transfusion Cervid CWD Prion disease Prions in blood White-tailed deer
ABSTRACT
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSEs) that affects free-ranging and captive cervid species. The infectious agent of CWD may be transmitted from ingestion of prions shed in bodily fluids (e.g. feces, urine, saliva, placenta tissue) of infected animals, contaminated pastures, and/or decomposing carcasses from dead animals. Studies have also demonstrated prion infectivity in whole blood or blood fractions of CWD infected animals. To determine if CWD-infected blood contained sufficient levels of prion infectivity to cause disease, recipient deer were inoculated intravenously (IV) with blood derived from a CWD- infected white-tailed deer. We found that the CWD agent can be successfully transmitted to white-tailed deer by a single intravenous blood transfusion. The incubation period was associated with recipient prion protein genotype at codon 96 with the GG96 recipient incubating for 25.6 months and the GS96 recipient incubating for 43.6 months. This study complements and supports an earlier finding that CWD can be transmitted to deer by intravenous blood transfusion from white-tailed deer with CWD.
Chronic wasting disease (CWD) is a naturally occurring transmissible spongiform encephalopathy (TSEs) of cervids. Other TSEs include scrapie in sheep and goats, bovine spongiform encephalopathy (BSE), and sporadic and familial Creutzfeldt-Jakob disease (CJD) in humans. The CWD agent has a wide host range among various species of free- ranging and captive cervids, including mule deer (Odocoileus hemi-onus) (Williams & Young, 1980; Spraker et al., 1997; Miller & Wild, 2004), white-tailed deer (Odocoileus virginianus) (Spraker et al., 1997; Miller & Wild, 2004), Rocky Mountain elk (Cervus elaphus nelsoni) (Williams & Young, 1982), moose (Alces alces shirasi) (Baeten et al., 2007; Kreeger et al., 2006), and reindeer (Rangifer tarandus tarandus) (Benestad et al., 2016; Moore et al., 2016). The infectious agent of CWD may be transmitted from ingestion of prions shed in bodily fluids (e.g. feces, urine, saliva) or placenta tissue of infected animals, contaminated pastures, and/or decomposing carcasses from dead animals (Haley et al., 2011; Haley et al., 2009; Mathiason et al., 2010; Mathiason et al., 2006). A limited number of reports have demonstrated prion infectivity in whole blood or blood fractions of CWD infected animals (Mathiason et al., 2010; Mathiason et al., 2006; Kramm et al., 2017). To determine if CWD-infected blood contained sufficient levels of prion infectivity to cause disease, recipient deer consisting of three female deer of approximately 2 years of age were inoculated intravenously (IV) with 100 mL of blood immediately after collection from a CWD-infected white-tailed deer (animal ID: 936). Deer 936 was a 21.8-month-old male white-tailed deer that was intracranially (IC) inoculated with 1 mL of a 10% (wt./vol) brain homogenate (derived from a pool of white- tailed deer brainstem material from Wisconsin) at 3 months of age. The procedure for IC inoculation of fawns has been described previously (Greenlee et al., 2011). Donor deer 936 presented with clinical signs of neurologic disease approximately ~17.8 months post inoculation at which time blood was collected by jugular venipuncture into 50 mL syringes containing 7 mL of citrate phosphate dextrose adenine solution anticoagulant (CPDA-1) that were immediately pooled and used as inoculum. Deer 936 was determined CWD positive based on accumu-lation of abnormal prion protein (PrPSc) by immunohistochemistry (IHC) in the brainstem at the level of the obex, the palatine tonsil, and the retropharyngeal lymph node (RLN). Recipient deer were initially housed in separate biosafety level 2 facilities following exposure to CWD. Non-inoculated control deer (n =3) were kept with the CWD-free herd on pasture at the National Animal Disease Center. All white-tailed deer (including donor animals) were genotyped and determined to be homozygous QQ at codons 95 and 226, but there were polymorphisms at codon 96. The donor deer (936) and two recipient deer (940, 942) were homozygous G at codon 96, and a single recipient deer (941) was het-erozygous GS at codon 96.
The animals were fed pelleted growth and maintenance rations that contained no ruminant protein, and clean water was available ad libi-tum. Deer were observed daily for the development of clinical signs of CWD (e.g., behavioral abnormalities, excess salivation, and emaciation) and were euthanized at the onset of unequivocal clinical signs of disease, or at the end of the observation period. At necropsy, duplicate tissue samples were collected and either frozen or stored in 10% buffered neutral formalin. For detection of PrPSc, slides were stained by an automated immunohistochemistry (IHC) method using primary anti-body F99/F96.7.1, described previously (Greenlee et al., 2012; Greenlee et al., 2006).
At the completion of the study, two of the three IV inoculated deer were determined CWD positive. The two positive deer presented with clinical signs and were euthanized at 25.6- and 43.6-months post inoc-ulation. These deer had detectable pathogenic prion protein (PrPSc) in the CNS and various non-CNS tissues (lymphoid tissues comprised of retropharyngeal lymph node (RPLN), tonsils (palatine and pharyngeal), spleen, recto-anal mucosa-associated lymphoid tissue (RAMALT), gut- associated lymphoid tissue (GALT) of the small intestines, and the enteric nervous system (Table 1). Deer #942 was euthanized 2.9 months post inoculation due to intercurrent disease, and no PrPSc was detectable by IHC, although it’s probable that this deer would have developed CWD given a longer duration of incubation.
This study complements and reinforces earlier findings that CWD can be transmitted to deer by intravenous blood transfusion from white- tailed deer with CWD (Mathiason et al., 2010; Mathiason et al., 2006). In a previous study, a group of eight, 6-month-old fawns were IV inoc-ulated with ~250 mL of whole blood derived from experimentally IC inoculated CWD positive white-tailed deer (Mathiason et al., 2010). In this study, all eight deer were determined to be CWD positive by IHC of all relevant tissues, and began to show clinical signs of TSE between 15 and 26 months post inoculation (Mathiason et al., 2010). While similar results were obtained in our study, we determined that only 100 mL of CWD-infected blood contained sufficient levels of prion infectivity to cause disease compared to the 250 mL of whole blood used by Mathiason et al. (Mathiason et al., 2010). In an earlier study, a cohort of three 6-month-old white-tailed deer fawns were exposed to the agent of CWD via either a single intraperitoneal (IP) inoculation (n =2) or an IV transfusion (n =1) of blood derived from a naturally infected CWD positive mule deer (Mathiason et al., 2006). Similar to our findings, the fawn that received blood via IV transfusion had detectable PrPSc in the CNS (medulla at the level of the obex), tonsil, and retropharyngeal lymph nodes (Mathiason et al., 2006); however, it did not present with clinical signs and was euthanized 18 months post inoculation (Mathia-son et al., 2006).
We demonstrate here that the CWD agent can be successfully transmitted to white-tailed deer by a single intravenous blood trans-fusion from CWD-infected white-tailed deer. The incubation period appeared to be associated with recipient genotype with the GG96 deer (940) incubating for 25.6 months, while the GS96 deer (941) incubated for 43.6 months; however, we take into consideration the limitation of the small sample size in this study. While a previous and larger study showed similar results, we determined that only 100 mL of CWD- infected blood (~2.5 times less than previously shown in (Mathiason et al., 2010)) contained sufficient levels of prion infectivity to cause disease. The identification of blood-borne transmission of the CWD agent is important in reinforcing the risk of exposure to CWD via blood as well as the possibility of hematogenous transmission of the CWD agent through insect vector. Finally, these results further highlight the importance of developing a sensitive and reproducible blood-based test to detect pre-clinical CWD, and warrant the continued advancement and evaluation of sensitive antemortem diagnostic tests for the detection of PrPSc in blood of asymptomatic cervids early in the incubation period.
Funding This research was supported in part by an appointment to the Agri-cultural Research Service (ARS) Research Participation Program administered by the Oak Ridge Institute for Science and Education (ORISE) through an interagency agreement between the U.S. Depart-ment of Energy (DOE) and the U.S. Department of Agriculture (USDA). ORISE is managed by ORAU under DOE contract number DE- SC0014664. All opinions expressed in this paper are the author’s and do not necessarily reflect the policies and views of USDA, ARS, DOE, or ORAU/ORISE. This research was funded in its entirety by congressio-nally appropriated funds to the United States Department of Agriculture, Agricultural Research Service. The funders of the work did not influence study design, data collection and analysis, decision to publish, or the preparation of the manuscript. * Corresponding author. E-mail address: justin.greenlee@usda.gov (J.J. Greenlee). Contents lists available at ScienceDirect Research in Veterinary Science journal homepage: www.elsevier.com/locate/rvsc https://doi.org/10.1016/j.rvsc.2020.10.009Received 7 May 2020; Received in revised form 9 October 2020; Accepted 14 October 2020
''We found that the CWD agent can be successfully transmitted to white-tailed deer by a single intravenous blood transfusion with a mean incubation period of approximately 35 months and an attack rate of 100%.''
Published: 15 May 2023
Ticks harbor and excrete chronic wasting disease prions
H. N. Inzalaco, F. Bravo-Risi, R. Morales, D. P. Walsh, D. J. Storm, J. A. Pedersen, W. C. Turner & S. S. Lichtenberg
In the host, CWD presents with a broad distribution of disease-associated prions (PrPCWD) in peripheral tissues and biological fluids prior to neuroinvasion. Blood of prion-infected animals harbors infectivity at the pre-symptomatic disease stage with relatively higher circulating amounts of PrPCWD than those found in urine8 or feces9. Animal challenge studies demonstrate that CWD-positive whole blood has a disease attack rate of up to 100% in cervids following intravenous exposure with 250 mL and 22% in cervidized mice following oral exposure with 150 µL10.
***> Antler velvet is rich in blood and nervous supply and may represent a source of infectious material as the velvet is shed every year.
***> These findings demonstrate prion infectivity accumulates in antler velvet and may have impact on marketing of this product.
SUNDAY, JULY 24, 2016
Chronic Wasting Disease Prions in Elk Antler Velvet and Marketing of this Product in Nutritional Supplements for Humans?
Antler velvet is rich in blood and nervous supply and may represent a source of infectious material as the velvet is shed every year.
P74 High Prevalence of CWD prions in male reproductive samples
The results showed positive CWD prion detection in testes, epididymis and seminal fluid samples. A high prevalence of CWD-PrPSc was found in samples collected at the late-presymptomatic stage of the disease. Our results showed a correlation between the presence of CWD-PrPSc in male reproductive organs and blood. These findings demonstrate a high efficiency of CWD prion detection by PMCA in testes, epididymis and seminal fluid, and offer a possibility for a routine screening of semen samples to be commercially distributed for artificial insemination. Our results may uncover new opportunities to understand the mechanisms of CWD spreading and decrease putative inter-individual transmission associated to insemination using CWD contaminated specimens.
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
Original Paper Open access Published: 22 August 2022 Volume 144, pages 767–784, (2022)
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In contrast, in cervids affected with CWD, infectivity has been found in the lymphatic system, salivary gland, intestinal tract, muscles, antler velvet, blood, urine, saliva, and feces [4], which have been demonstrated to be transmissible [57]. CWD prions are shed into the environment via bodily fluids and excreta. They bind to soil and are taken up by plants, making the environment infectious for decades to come [4, 48]. The persistence of CWD prions in the environment amplifies the already effective transmission within and between cervid species. Therefore, CWD is considered to be the most contagious prion disease with fast spreading and efficient horizontal transmission.
Our findings strongly suggest that CWD should be regarded as an actual public health risk. Here, we use humanized mice to show that CWD prions can cross the species barrier to humans, and remarkably, infectious prions can be excreted in feces.
Many factors have to be taken into account for prions to be able to cross the species barrier. Notably, the homology between the host PrP primary structure and the donor PrPSc plays a crucial role in species barrier [9, 13, 21, 59]. In addition, the existence of different CWD strains and the impact of the Prnp polymorphism, the extensive incubation period, and the atypical clinical presentation should be considered when investigating the risk of CWD. Determining that CWD poses a significant risk to human health is of a crucial importance to prevent a public health and economic crisis similar—if not greater—to that of BSE transmission to humans (i.e., vCJD) because CWD not only affects farmed but also free-ranging cervids and therefore cannot be controlled under the same circumstances that BSE in cattle was controlled.
Several studies have evaluated the susceptibility of humans to CWD [41]. Most in vitro studies had found that CWD prions are capable to convert human PrPC, however, either the efficiency of the conversion was low or relied on protein modifications by denaturation [5,6,7, 35, 47]. RT-QuIC assay showed that PrPCWD can seed the conversion of human recombinant PrP, however, PrPBSE did not seed it making the veracity of these results questionable [19]. Transgenic mouse models overexpressing the human prion protein have been extensively used to assess the transmission of various human prions in vivo, thus, they are also used as a model to test the zoonotic potential of prions from other species such as cervids (CWD) [32, 33, 52, 55, 56, 60, 61, 63]. Different transgenic lines with different polymorphism at residue 129 (M or V), expressing human PrPC at different expression levels, and in variable tissues (because of the transgene construct), were used in these studies, that were infected with different sources of CWD prions.
CWD transmission to humanized mice was assessed in all these studies by monitoring the clinical signs, examining the brain for neuropathology associated with prion disease, and IHC staining for PrP deposits. Brains were also analyzed by Western blot after PK digestion for detection of PrPres. Wilson and coworkers used an antigen immunoassay, to screen for PrPCWD [63], and Race et al. used RT-QuIC to assess the PrP amyloid formation in the brain of CWD inoculated humanized mice [52]. In three of the in vivo studies [32, 52, 63], clinical signs were observed in a relatively small number of CWD inoculated mice. Race et al. showed positive seeding activity in the brains of very few suspect animals, however, these results were inconsistent, and the authors questioned their significance [52]. Prion disease could not be detected in any of the other studies. As RT-QuIC assay was not available at the time of other reports [25, 32, 55, 56], they might have missed subclinical manifestations in their CWD-inoculated humanized mice. In addition, except for one study where the mice were kept up to 798 dpi [52], in most of the studies the experiments were terminated between 500 and 600 dpi. In our study, tg650 mice were kept for up to > 900 dpi, which is at least + 15% of the survival compared to the longest study. This could be a significant asset to this line when it comes to human prion diseases with a very prolonged incubation period.
Our data also suggest that prions found in the periphery may hold higher zoonotic potential than prions found in neural tissues. In fact, upon second passage, 50% of the tg650 mice inoculated with fecal homogenates from mouse #327 had succumbed with terminal disease compared to only 20% of brain/spinal cord homogenates inoculated-tg650 mice suggesting that hCWD prions found in feces transmit disease more efficiently. Our results also suggest that epidemiological studies [25] may have missed subclinical and atypical infections that are/might be transmissible, undetected by the gold standard tests, i.e., Western blot, ELISA, and IHC.
The overall risk for zoonotic transmission of CWD is likely lower than that for BSE; however, rather than predicting the absolute zoonotic risk for CWD, our study indicates the possibility of atypical features in humans. Furthermore, our findings provide striking insights into how CWD might manifest in humans and the impact it may have on human health. We have used Wisc-1/CWD1, one of the most common CWD strains, notably white-tailed deer prions, which have been shown to be more prone to generate human prions in vitro [47]. This implies a high risk of exposure to this strain, e.g., through consumption or handling of infected carcasses, in contrast to rarer CWD strains, and therefore, an actual risk for human health. Fecal shedding of infectious prions, if it occurs in humans, is particularly concerning because of potential human-to-human transmission and adaptation of hCWD. Overall, our findings suggest that CWD surveillance in humans should encompass a wider spectrum of tissues/organs tested and include new criteria in the diagnosis of potential patients.
Transmission of prion infectivity from CWD-infected macaque tissues to rodent models demonstrates the zoonotic potential of chronic wasting disease
“Our findings demonstrate that macaques, considered the best model for the zoonotic potential of prions, were infected upon CWD challenge, including the oral one.”
***> CHRONIC WASTING DISEASE CWD TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION DISEASE ZOONOSIS, ZOONOTIC
“If CWD in humans is found to be contagious and transmissible among humans, as it is in cervids [57], the spread of the disease within humans might become endemic.”
PART 2. TPWD CHAPTER 65. DIVISION 1. CWD
31 TAC §§65.82, 65.85, 65.88
The Texas Parks and Wildlife Commission in a duly noticed meeting on May 25, 2023 adopted amendments to 31 TAC §§65.82, 65.85, and §65.88, concerning Disease Detection and Response, without changes to the proposed text as published in the April 21, 2023, issue of the Texas Register (48 TexReg 2048). The rules will not be republished.
Currently, there is scientific evidence to suggest that CWD has zoonotic potential; however, no confirmed cases of CWD have been found in humans.
17 DETECTION OF CHRONIC WASTING DISEASE PRIONS IN PROCESSED MEATS.
Rebeca Benavente1, Francisca Bravo1,2, Paulina Soto1,2, J. Hunter Reed3, Mitch Lockwood3, Rodrigo Morales1,2
1Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, USA. 2Universidad Bernardo O’Higgins, Santiago, Chile. 3Texas Parks and Wildlife, Austin, USA
Abstract
The zoonotic potential of chronic wasting disease (CWD) remains unknown. Currently, there are no known natural cases of CWD transmission to humans but increasing evidence suggests that the host range of CWD is not confined only to cervid species. Alarmingly, recent experimental evidence suggests that certain CWD isolates can induce disease in non-human primates. While the CDC strongly recommends determining CWD status in animals prior to consumption, this practice is voluntary. Consequently, it is plausible that a proportion of the cervid meat entering the human food chain may be contaminated with CWD. Of additional concern is that traditional diagnostic techniques used to detect CWD have relatively low sensitivity and are only approved for use in tissues other than those typically ingested by humans. In this study, we analyzed different processed meats derived from a pre-clinical, CWD-positive free-ranging elk. Products tested included filets, sausages, boneless steaks, burgers, ham steaks, seasoned chili meats, and spiced meats. CWD-prion presence in these products were assessed by PMCA using deer and elk substrates. Our results show positive prion detection in all products. To confirm the resilience of CWD-prions to traditional cooking methods, we grilled and boiled the meat products and evaluated them for any remnant PMCA seeding activity. Results confirmed the presence of CWD-prions in these meat products suggesting that infectious particles may still be available to people even after cooking. Our results strongly suggest ongoing human exposure to CWD-prions and raise significant concerns of zoonotic transmission through ingestion of CWD contaminated meat products.
***> Products tested included filets, sausages, boneless steaks, burgers, ham steaks, seasoned chili meats, and spiced meats.
***> CWD-prion presence in these products were assessed by PMCA using deer and elk substrates.
***> Our results show positive prion detection in all products.
***> Results confirmed the presence of CWD-prions in these meat products suggesting that infectious particles may still be available to people even after cooking.
***> Our results strongly suggest ongoing human exposure to CWD-prions and raise significant concerns of zoonotic transmission through ingestion of CWD contaminated meat products.
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9 Carrot plants as potential vectors for CWD transmission.
Paulina Soto1,2, Francisca Bravo-Risi1,2, Claudio Soto1, Rodrigo Morales1,2
1Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, USA. 2Universidad Bernardo O’Higgins, Santiago, Chile
***> We show that edible plant components can absorb prions from CWD-contaminated soils and transport them to their aerial parts.
***> Our results indicate that edible plants could participate as vectors of CWD transmission
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Transmission of prion infectivity from CWD-infected macaque tissues to rodent models demonstrates the zoonotic potential of chronic wasting disease.
Samia Hannaoui1,2, Ginny Cheng1,2, Wiebke Wemheuer3, Walter Schulz-Schaeffer3, Sabine Gilch1,2, Hermann Schatzl1,2 1University of Calgary, Calgary, Canada. 2Calgary Prion Research Unit, Calgary, Canada. 3Institute of Neuropathology, Medical Faculty, Saarland University, Homburg/Saar, Germany
***> Further passage to cervidized mice revealed transmission with a 100% attack rate.
***> Our findings demonstrate that macaques, considered the best model for the zoonotic potential of prions, were infected upon CWD challenge, including the oral one.
****> The disease manifested as atypical in macaques and initial transgenic mouse transmissions, but with infectivity present at all times, as unveiled in the bank vole model with an unusual tissue tropism.
***> Epidemiologic surveillance of prion disease among cervid hunters and people likely to have consumed venison contaminated with chronic wasting disease
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Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD
Samia Hannaouia, Irina Zemlyankinaa, Sheng Chun Changa, Maria Immaculata Arifina, Vincent Béringueb, Debbie McKenziec, Hermann M. Schatzla, and Sabine Gilcha
Results: Here, we provide the strongest evidence supporting the zoonotic potential of CWD prions, and their possible phenotype in humans. Inoculation of mice expressing human PrPCwith deer CWD isolates (strains Wisc-1 and 116AG) resulted in atypical clinical manifestations in > 75% of the mice, with myoclonus as leading clinical sign. Most of tg650brain homogenates were positive for seeding activity in RT-QuIC. Clinical disease and presentation was transmissible to tg650 mice and bank voles. Intriguingly, protease-resistant PrP in the brain of tg650 mice resembled that found in a familial human prion disease and was transmissible upon passage. Abnormal PrP aggregates upon infection with Wisc-1 were detectable in thalamus, hypothalamus, and midbrain/pons regions.
Unprecedented in human prion disease, feces of CWD-inoculated tg650 mice harbored prion seeding activity and infectious prions, as shown by inoculation of bank voles and tg650 with fecal homogenates.
Conclusions: This is the first evidence that CWD can infect humans and cause disease with a distinctive clinical presentation, signature, and tropism, which might be transmissible between humans while current diagnostic assays might fail to detect it. These findings have major implications for public health and CWD-management.
https://www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286 The finding that infectious PrPSc was shed in fecal material of CWD-infected humanized mice and induced clinical disease, different tropism, and typical three banding pattern-PrPres in bank voles that is transmissible upon second passage is highly concerning for public health. The fact that this biochemical signature in bank voles resembles that of the Wisc-1 original deer isolate and is different from that of bvWisc-1, in the migration profile and the glyco-form-ratio, is valid evidence that these results are not a product of contamination in our study. If CWD in humans is found to be contagious and transmissible among humans, as it is in cervids [57], the spread of the disease within humans might become endemic.
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
Acta Neuropathol 144, 767–784 (2022). https://doi.org/10.1007/s00401-022-02482-9
Published
22 August 2022
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
Samia Hannaoui1 · Irina Zemlyankina1 · Sheng Chun Chang1 · Maria Immaculata Arifn1 · Vincent Béringue2 · Debbie McKenzie3 · Hermann M. Schatzl1 · Sabine Gilch1
Received: 24 May 2022 / Revised: 5 August 2022 / Accepted: 7 August 2022
© The Author(s) 2022
Abstract
Prions cause infectious and fatal neurodegenerative diseases in mammals. Chronic wasting disease (CWD), a prion disease of cervids, spreads efficiently among wild and farmed animals. Potential transmission to humans of CWD is a growing concern due to its increasing prevalence. Here, we provide evidence for a zoonotic potential of CWD prions, and its probable signature using mice expressing human prion protein (PrP) as an infection model. Inoculation of these mice with deer CWD isolates resulted in atypical clinical manifestation with prion seeding activity and efficient transmissible infectivity in the brain and, remarkably, in feces, but without classical neuropathological or Western blot appearances of prion diseases. Intriguingly, the protease-resistant PrP in the brain resembled that found in a familial human prion disease and was transmissible upon second passage. Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a different clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. Furthermore, the presence of infectious prions in feces is concerning because if this occurs in humans, it is a source for human-to-human transmission. These findings have strong implications for public health and CWD management.
Keywords Chronic wasting disease · CWD · Zoonotic potential · Prion strains · Zoonotic prions
HIGHLIGHTS OF THIS STUDY
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Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a different clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. Furthermore, the presence of infectious prions in feces is concerning because if this occurs in humans, it is a source for human-to-human transmission. These findings have strong implications for public health and CWD management.
In this study, we evaluated the zoonotic potential of CWD using a transgenic mouse model overexpressing human M129-PrPC (tg650 [12]). We inoculated tg650 mice intracerebrally with two deer CWD isolates, Wisc-1 and 116AG [22, 23, 27, 29]. We demonstrate that this transgenic line was susceptible to infection with CWD prions and displayed a distinct leading clinical sign, an atypical PrPSc signature and unusual fecal shedding of infectious prions. Importantly, these prions generated by the human PrP transgenic mice were transmissible upon passage. Our results are the first evidence of a zoonotic risk of CWD when using one of the most common CWD strains, Wisc-1/CWD1 for infection. We demonstrated in a human transgenic mouse model that the species barrier for transmission of CWD to humans is not absolute. The fact that its signature was not typical raises the questions whether CWD would manifest in humans as a subclinical infection, whether it would arise through direct or indirect transmission including an intermediate host, or a silent to uncovered human-to-human transmission, and whether current detection techniques will be suffcient to unveil its presence.
Our findings strongly suggest that CWD should be regarded as an actual public health risk. Here, we use humanized mice to show that CWD prions can cross the species barrier to humans, and remarkably, infectious prions can be excreted in feces.
Our results indicate that if CWD crosses the species-barrier to humans, it is unlikely to resemble the most common forms of human prion diseases with respect to clinical signs, tissue tropism and PrPSc signature. For instance, PrPSc in variable protease-sensitive prionopathy (VPSPr), a sporadic form of human prion disease, and in the genetic form Gerstmann-Sträussler-Scheinker syndrome (GSS) is defined by an atypical PK-resistant PrPSc fragment that is non-glycosylated and truncated at both C- and N-termini, with a molecular weight between 6 and 8 kDa [24, 44–46]. These biochemical features are unique and distinctive from PrPSc (PrP27-30) found in most other human or animal prion disease. The atypical PrPSc signature detected in brain homogenate of tg650 mice #321 (1st passage) and #3063 (2nd passage), and the 7–8 kDa fragment (Figs. 2, 4) are very similar to that of GSS, both in terms of migration profile and the N-terminal cleavage site.
CWD in humans might remain subclinical but with PrPSc deposits in the brain with an unusual morphology that does not resemble the patterns usually seen in different prion diseases (e.g., mouse #328; Fig. 3), clinical with untraceable abnormal PrP (e.g., mouse #327) but still transmissible and uncovered upon subsequent passage (e.g., mouse #3063; Fig. 4), or prions have other reservoirs than the usual ones, hence the presence of infectivity in feces (e.g., mouse #327) suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable.
suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable.
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Supplementary Information The online version contains supplementary material available at
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Fortuitous generation of a zoonotic cervid prion strain
Manuel Camacho, Xu Qi, Liuting Qing, Sydney Smith, Jieji Hu, Wanyun Tao, Ignazio Cali, Qingzhong Kong. Department of Pathology, Case Western Reserve University, Cleveland, USA
Aims: Whether CWD prions can infect humans remains unclear despite the very substantial scale and long history of human exposure of CWD in many states or provinces of USA and Canada. Multiple in vitro conversion experiments and in vivo animal studies indicate that the CWD-to-human transmission barrier is not unbreakable. A major long-term public health concern on CWD zoonosis is the emergence of highly zoonotic CWD strains. We aim to address the question of whether highly zoonotic CWD strains are possible.
Materials and Methods: We inoculated several sCJD brain samples into cervidized transgenic mice (Tg12), which were intended as negative controls for bioassays of brain tissues from sCJD cases who had potentially been exposed to CWD. Some of the Tg12 mice became infected and their brain tissues were further examined by Western blot as well as serial passages in humanized or cervidized mice.
Results: Passage of sCJDMM1 in transgenic mice expressing elk PrP (Tg12) resulted in a “cervidized” CJD strain that we termed CJDElkPrP. We observed 100% transmission of the original CJDElkPrP in transgenic mice expressing human PrP. We passaged CJDElkPrP two more times in the Tg12 mice. We found that such second and third passage CJDElkPrP prions retained 100% transmission rate in the humanized mice, despite that the natural elk CWD isolates and CJDElkPrP share the same elk PrP sequence. In contrast, we and others found zero or poor transmission of natural elk CWD isolates in humanized mice.
Conclusions: Our data indicate that highly zoonotic cervid prion strains are not only possible but also can retain zoonotic potential after serial passages in cervids, suggesting a very significant and serious long-term risk of CWD zoonosis given that the broad and continuing spread of CWD prions will provide fertile grounds for the emergence of zoonotic CWD strains over time.
Funded by: NIH Grant number: R01NS052319, R01NS088604, R01NS109532
Acknowledgement: We want to thank the National Prion Disease Pathology Surveillance Center and Drs. Allen Jenny and Katherine O'Rourke for providing the sCJD samples and the CWD samples used in this study, respectively
"Our data indicate that highly zoonotic cervid prion strains are not only possible but also can retain zoonotic potential after serial passages in cervids, suggesting a very significant and serious long-term risk of CWD zoonosis given that the broad and continuing spread of CWD prions will provide fertile grounds for the emergence of zoonotic CWD strains over time."
PRION 2023 CONTINUED;
A probable diagnostic marker for CWD infection in humans
Xu Qi, Liuting Qing, Manuel Camacho, Ignazio Cali, Qingzhong Kong. Department of Pathology, Case Western Reserve University, Cleveland, USA
Aims: Multiple in vitro CWD-seeded human PrP conversion experiments and some animal model studies indicate that the species barrier for CWD to human transmission can be overcome, but whether CWD prion can infect humans in real life remains controversial. The very limited understanding on the likely features of CWD infection in humans and the lack of a reliable diagnostic marker for identification of acquired human CWD cases contribute to this uncertainty. We aim to stablish such a reliable diagnostic marker for CWD infections in humans should they occur.
Materials and Methods: A couple of PrPSc-positive spleens were identified from humanized transgenic mice inoculated with either CWD or sCJDMM1. Prions in these spleens were compared by bioassays in cervidized or humanized transgenic mice. A couple of PrPSc-positive spleens from UK sCJDMM1 patients were also examined similarly as controls with no exposure to CWD.
Results: We have detected two prion-positive spleens in humanized transgenic mice inoculated with some CWD isolates. Such experimentally generated splenic “humanized” CWD prions (termed eHuCWDsp) appear indistinguishable from prions in the brain of sCJDMM1 patients on Western blot. We compared eHuCWDsp with prions in the spleen from humanized mice infected with sCJDMM1 (termed sCJDMM1sp) by bioassays in cervidized or humanized transgenic mice. Significantly, we found that eHuCWDsp can efficiently infect not only the humanized mice but also cervidized transgenic mice, and cervidized mice infected by eHuCWDsp produced PrPSc and brain pathology that are practically identical to those of CWD-infected cervidized mice. In contrast, sCJDMM1sp, similar to prions from sCJDMM1 patient brains, is poorly transmissible in the cervidized mice.
Conclusions: Our data demonstrate that high transmissibility with CWD features of splenic prions in cervidized transgenic mice is unique to acquired human CWD prions, and it may serve as a reliable marker to identify the first acquired human CWD cases.
Funded by: NIH Grant number: R01NS052319, R01NS088604, R01NS109532
Acknowledgement: We want to thank the National Prion Disease Pathology Surveillance Center and Drs. Allen Jenny and Katherine O'Rourke for providing the sCJD samples and the CWD samples used in this study, respectively.
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PRION 2023 CONTINUED;
Prion 2023 Experimental Oronasal Inoculation of the Chronic Wasting Disease Agent into White Tailed Deer
Author list: Sarah Zurbuchena,b , S. Jo Moorea,b , Jifeng Biana , Eric D. Cassmanna , and Justin J. Greenleea . a. Virus and Prion Research Unit, National Animal Disease Center, ARS, United States Department of Agriculture, Ames, IA, US b. Oak Ridge Institute for Science and Education (ORISE), U.S. Department of Energy, Oak Ridge, TN, United States
Aims: The purpose of this experiment was to determine whether white-tailed deer (WTD) are susceptible to inoculation of chronic wasting disease (CWD) via oronasal exposure.
Materials and methods: Six male, neutered WTD were oronasally inoculated with brainstem material (10% w/v) from a CWD-positive wild-type WTD. The genotypes of five inoculated deer were Q95/G96 (wild-type). One inoculated deer was homozygous S at codon 96 (96SS). Cervidized (Tg12; M132 elk PrP) mice were inoculated with 1% w/v brainstem homogenate from either a 96GG WTD (n=10) or the 96SS WTD (n=10).
Results: All deer developed characteristic clinical signs of CWD including weight loss, regurgitation, and ataxia. The 96SS individual had a prolonged disease course and incubation period compared to the other deer. Western blots of the brainstem on all deer yielded similar molecular profiles. All deer had widespread lymphoid distribution of PrPCWD and neuropathologic lesions associated with transmissible spongiform encephalopathies. Both groups of mice had a 100% attack rate and developed clinical signs, including loss of body condition, ataxia, and loss of righting reflex. Mice inoculated with material from the 96SS deer had a significantly shorter incubation period than mice inoculated with material from 96GG deer (Welch two sample T-test, P<0.05). Serial dilutions of each inocula suggests that differences in incubation period were not due to a greater concentration of PrPCWD in the 96SS inoculum. Molecular profiles from western blot of brain homogenates from mice appeared similar regardless of inoculum and appear similar to those of deer used for inoculum.
Conclusions: This study characterizes the lesions and clinical course of CWD in WTD inoculated in a similar manner to natural conditions. It supports previous findings that 96SS deer have a prolonged disease course. Further, it describes a first pass of inoculum from a 96SS deer in cervidized mice which shortened the incubation period.
Funded by: This research was funded in its entirety by congressionally appropriated funds to the United States Department of Agriculture, Agricultural Research Service. The funders of the work did not influence study design, data collection, analysis, decision to publish, or preparation of the manuscript.
Acknowledgement: We thank Ami Frank and Kevin Hassall for their technical contributions to this project.
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PRION 2023 CONTINUED;
The detection and decontamination of chronic wasting disease prions during venison processing
Marissa S. Milstein1,2, Marc D. Schwabenlander1,2, Sarah C. Gresch1,2, Manci Li1,2, Stuart Lichtenberg1,2, Rachel Shoemaker1,2, Gage R. Rowden1,2, Jason C. Bartz2,3 , Tiffany M. Wolf2,4, Peter A. Larsen1,2
Presenting author: Tiffany M. Wolf 1 Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA 2 Minnesota Center for Prion Research and Outreach, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA 3 Department of Medical Microbiology and Immunology, School of Medicine, Creighton University, Omaha, Nebraska, USA 4 Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA
Aims: There is a growing concern that chronic wasting disease (CWD) prions in venison pose a risk to human health. CWD prions accumulate in infected deer tissues that commonly enter the human food chain through meat processing and consumption. The United States (US) Food and Drug Administration and US Department of Agriculture now formally consider CWD-positive venison unfit for human and animal consumption. Yet, the degree to which prion contamination occurs during routine venison processing is unknown. Here, we use environmental surface swab methods to: a) experimentally test meat processing equipment (i.e., stainless steel knives and polyethylene cutting boards) before and after processing CWD-positive venison and b) test the efficacy of five different disinfectant types (i.e., Dawn dish soap, Virkon-S, Briotech, 10% bleach, and 40% bleach) to determine prion decontamination efficacy.
Materials and Methods: We used a real-time quaking-induced conversion (RT-QuIC) assay to determine CWD infection status of venison and to detect CWD prions in the swabs. We collected three swabs per surface and ran eight technical replicates on RT-QuIC.
Results: CWD prions were detected on all cutting boards (n= 3; replicates= 8/8, 8/8, 8/8 and knives (n= 3; replicates= 8/8, 8/8, 8/8) used in processing CWD-positive venison, but not on those used for CWD-negative venison. After processing CWD-positive venison, allowing the surfaces to dry, and washing the cutting board with Dawn dish soap, we detected CWD prions on the cutting board surface (n= 3; replicates= 8/8, 8/8, 8/8) but not on the knife (n= 3, replicates = 0/8, 0/8, 0/8). Similar patterns were observed with Briotech (cutting board: n= 3; replicates= 7/8, 1/8, 0/8; knife: n= 3; replicates = 0/8, 0/8, 0/8). We did not detect CWD prions on the knives or cutting boards after disinfecting with Virkon-S, 10% bleach, and 40% bleach.
Conclusions: These preliminary results suggest that Dawn dish soap and Briotech do not reliably decontaminate CWD prions from these surfaces. Our data suggest that Virkon-S and various bleach concentrations are more effective in reducing prion contamination of meat processing surfaces; however, surface type may also influence the ability of prions to adsorb to surfaces, preventing complete decontamination. Our results will directly inform best practices to prevent the introduction of CWD prions into the human food chain during venison processing.
Acknowledgement: Funding was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR), the Rapid Agriculture Response Fund (#95385/RR257), and the Michigan Department of Natural Resources.
Theme: Animal prion diseases
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Prion 2023 Abstracts
8. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data.
***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison.
The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers.. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
Research Paper
Cellular prion protein distribution in the vomeronasal organ, parotid, and scent glands of white-tailed deer and mule deer
Anthony Ness, Aradhana Jacob, Kelsey Saboraki, Alicia Otero, Danielle Gushue, Diana Martinez Moreno, Melanie de Peña, Xinli Tang, Judd Aiken, Susan Lingle & Debbie McKenzieORCID Icon show less
Pages 40-57 | Received 03 Feb 2022, Accepted 13 May 2022, Published online: 29 May 2022
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ABSTRACT
Chronic wasting disease (CWD) is a contagious and fatal transmissible spongiform encephalopathy affecting species of the cervidae family. CWD has an expanding geographic range and complex, poorly understood transmission mechanics. CWD is disproportionately prevalent in wild male mule deer and male white-tailed deer. Sex and species influences on CWD prevalence have been hypothesized to be related to animal behaviours that involve deer facial and body exocrine glands. Understanding CWD transmission potential requires a foundational knowledge of the cellular prion protein (PrPC) in glands associated with cervid behaviours. In this study, we characterized the presence and distribution of PrPC in six integumentary and two non-integumentary tissues of hunter-harvested mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus). We report that white-tailed deer expressed significantly more PrPC than their mule deer in the parotid, metatarsal, and interdigital glands. Females expressed more PrPC than males in the forehead and preorbital glands. The distribution of PrPC within the integumentary exocrine glands of the face and legs were localized to glandular cells, hair follicles, epidermis, and immune cell infiltrates. All tissues examined expressed sufficient quantities of PrPC to serve as possible sites of prion initial infection, propagation, and shedding.
ARS RESEARCH Generation of human chronic wasting disease in transgenic mice
Publication Acceptance Date: 9/8/2021
Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research
Title: Generation of human chronic wasting disease in transgenic mice
Author item WANG, ZERUI - Case Western Reserve University (CWRU) item QIN, KEFENG - University Of Chicago item CAMACHO, MANUEL - Case Western Reserve University (CWRU) item SHEN, PINGPING - Case Western Reserve University (CWRU) item YUAN, JUE - Case Western Reserve University (CWRU) item Greenlee, Justin item CUI, LI - Jilin University item KONG, QINGZHONG - Case Western Reserve University (CWRU) item MASTRIANNI, JAMES - University Of Chicago item ZOU, WEN-QUAN - Case Western Reserve University (CWRU)
Submitted to: Acta Neuropathologica Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/8/2021 Publication Date: N/A Citation: N/A
Interpretive Summary: Prion diseases are invariably fatal neurologic diseases for which there is no known prevention or cure. Chronic wasting disease (CWD) is the prion disease of deer and elk and is present in farmed and free ranging herds throughout North America. To date there is no clear evidence that the CWD agent could be transmitted to humans. This manuscript describes the use of an in vitro technique, cell-free serial protein misfolding cyclic amplification (sPMCA), to generate a CWD prion that is infectious to transgenic mice expressing the human prion protein. This study provides the first evidence that CWD prions may be able to cause misfolding in the human prion protein. This information will impact medical experts and those involved in making policy for farmed cervids and wildlife.
Technical Abstract: Chronic wasting disease (CWD) is a cervid spongiform encephalopathy or prion disease caused by the infectious prion or PrPSc, a misfolded conformer of cellular prion protein (PrPC). It has rapidly spread in North America and also has been found in Asia and Europe. In contrast to the zoonotic mad cow disease that is the first animal prion disease found transmissible to humans, the transmissibility of CWD to humans remains uncertain although most previous studies have suggested that humans may not be susceptible to CWD. Here we report the generation of an infectious human PrPSc by seeding CWD PrPSc in normal human brain PrPC through the in vitro cell-free serial protein misfolding cyclic amplification (sPMCA). Western blotting confirms that the sPMCA-induced proteinase K-resistant PrPSc is a human form, evidenced by a PrP-specific antibody that recognizes human but not cervid PrP. Remarkably, two lines of humanized transgenic (Tg) mice expressing human PrP-129Val/Val (VV) or -129Met/Met (MM) polymorphism develop prion disease at 233 ± 6 (mean ± SE) days post-inoculation (dpi) and 552 ± 27 dpi, respectively, upon intracerebral inoculation with the sPMCA-generated PrPSc. The brain of diseased Tg mice reveals the electrophoretic profile of PrPSc similar to sporadic Creutzfeldt-Jakob disease (sCJD) MM1 or VV2 subtype but different neuropathological patterns. We believe that our study provides the first evidence that CWD PrPSc is able to convert human PrPC into PrPSc in vitro and the CWD-derived human PrPSc mimics atypical sCJD subtypes in humanized Tg mice.
''The brain of diseased Tg mice reveals the electrophoretic profile of PrPSc similar to sporadic Creutzfeldt-Jakob disease (sCJD) MM1 or VV2 subtype but different neuropathological patterns.''
''We believe that our study provides the first evidence that CWD PrPSc is able to convert human PrPC into PrPSc in vitro and the CWD-derived human PrPSc mimics atypical sCJD subtypes in humanized Tg mice.''
Published: 26 September 2021
Generation of human chronic wasting disease in transgenic mice
Zerui Wang, Kefeng Qin, Manuel V. Camacho, Ignazio Cali, Jue Yuan, Pingping Shen, Justin Greenlee, Qingzhong Kong, James A. Mastrianni & Wen-Quan Zou
Acta Neuropathologica Communications volume 9, Article number: 158 (2021)
Abstract
Chronic wasting disease (CWD) is a cervid prion disease caused by the accumulation of an infectious misfolded conformer (PrPSc) of cellular prion protein (PrPC). It has been spreading rapidly in North America and also found in Asia and Europe. Although bovine spongiform encephalopathy (i.e. mad cow disease) is the only animal prion disease known to be zoonotic, the transmissibility of CWD to humans remains uncertain. Here we report the generation of the first CWD-derived infectious human PrPSc by elk CWD PrPSc-seeded conversion of PrPC in normal human brain homogenates using in vitro protein misfolding cyclic amplification (PMCA). Western blotting with human PrP selective antibody confirmed that the PMCA-generated protease-resistant PrPSc was derived from the human PrPC substrate. Two lines of humanized transgenic mice expressing human PrP with either Val or Met at the polymorphic codon 129 developed clinical prion disease following intracerebral inoculation with the PMCA-generated CWD-derived human PrPSc. Diseased mice exhibited distinct PrPSc patterns and neuropathological changes in the brain. Our study, using PMCA and animal bioassays, provides the first evidence that CWD PrPSc can cross the species barrier to convert human PrPC into infectious PrPSc that can produce bona fide prion disease when inoculated into humanized transgenic mice.
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It is worth noting that the annual number of sporadic CJD (sCJD) cases in the USA has increased, with the total number of suspected and confirmed sCJD cases rising from 284 in 2003 to 511 in 2017 (https://www.cdc.gov/prions/cjd/occurrence-transmission.html). The greatly enhanced CJD surveillance and an aging population in the USA certainly contributed to the observed increase in annual sCJD case numbers in recent years, but the possibility cannot be excluded that some of the increased sCJD prevalence is linked to CWD exposure.
In the present study, using serial protein misfolding cyclic amplification (sPMCA) assay we generate PrPSc by seeding CWD prions in normal human brain homogenates. Importantly, we reveal that two lines of humanized Tg mice expressing human PrP-129VV and 129MM develop prion diseases upon intracerebral inoculation of the abnormal PrP generated by sPMCA. We believe that our study provides the first opportunity to dissect the clinical, pathological and biochemical features of the CWD-derived human prion disease in two lines of humanized Tg mice expressing two major human PrP genotypes, respectively.
i thought i might share some news about cwd zoonosis that i got, that i cannot share or post to the public yet, i promised for various reasons, one that it will cause a shit storm for sure, but it was something i really already knew from previous studies, but, i was told that ;
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''As you can imagine, 2 and 5 (especially 5) may raise alarms. The evidence we have for 4 are not as strong or tight as I would like to have. At this point, please do not post any of the points publicly yet, but you can refer to points 1-3 in private discussions and all 5 points when discussing with relevant public officials to highlight the long-term risks of CWD zoonosis.''
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so, i figure your as about as official as it gets, and i think this science is extremely important for you to know and to converse about with your officials. it's about to burn a whole in my pocket. this is about as close as it will ever get for cwd zoonosis to be proven in my time, this and what Canada Czub et al found with the Macaques, plus an old study from cjd surveillance unit back that showed cjd and a 9% increase in risk from folks that eat venison, i will post all this below for your files Sir. i remember back in the BSE nvCJD days, from when the first BSE case in bovine was confirmed around 1984 maybe 83, i forget the good vets named that screwed it up first, Carol something, but from 83ish to 95 96 when nvCJD was linked to humans from BSE in cattle, so that took 10 to 15 years. hell, at that rate, especially with Texas and cwd zoonsis, hell, i'll be dead before it's official, if ever, so here ya go Sir. there was a grant study on cwd zoonosis that had been going on for some time, i followed it over the years, then the grant date for said study had expired, so, i thought i would write the good Professor about said study i.e. Professor Kong, CWRU et al. i will post the grant study abstract first, and then after that, what reply i got back, about said study that i was told not to post/publish...
CWD ZOONOSIS GRANT FIRST;
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Cervid to human prion transmission
Kong, Qingzhong
Case Western Reserve University, Cleveland, OH, United States
Abstract Prion disease is transmissible and invariably fatal. Chronic wasting disease (CWD) is the prion disease affecting deer, elk and moose, and it is a widespread and expanding epidemic affecting 22 US States and 2 Canadian provinces so far. CWD poses the most serious zoonotic prion transmission risks in North America because of huge venison consumption (>6 million deer/elk hunted and consumed annually in the USA alone), significant prion infectivity in muscles and other tissues/fluids from CWD-affected cervids, and usually high levels of individual exposure to CWD resulting from consumption of the affected animal among often just family and friends. However, we still do not know whether CWD prions can infect humans in the brain or peripheral tissues or whether clinical/asymptomatic CWD zoonosis has already occurred, and we have no essays to reliably detect CWD infection in humans. We hypothesize that: (1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues; (2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence; (3) Reliable essays can be established to detect CWD infection in humans; and (4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches.
Aim 1 will prove that the classical CWD strain may infect humans in brain or peripheral lymphoid tissues at low levels by conducting systemic bioassays in a set of humanized Tg mouse lines expressing common human PrP variants using a number of CWD isolates at varying doses and routes. Experimental human CWD samples will also be generated for Aim 3.
Aim 2 will test the hypothesis that the cervid-to-human prion transmission barrier is dependent on prion strain and influenced by the host (human) PrP sequence by examining and comparing the transmission efficiency and phenotypes of several atypical/unusual CWD isolates/strains as well as a few prion strains from other species that have adapted to cervid PrP sequence, utilizing the same panel of humanized Tg mouse lines as in Aim 1.
Aim 3 will establish reliable essays for detection and surveillance of CWD infection in humans by examining in details the clinical, pathological, biochemical and in vitro seeding properties of existing and future experimental human CWD samples generated from Aims 1-2 and compare them with those of common sporadic human Creutzfeldt-Jakob disease (sCJD) prions.
Aim 4 will attempt to detect clinical CWD-affected human cases by examining a significant number of brain samples from prion-affected human subjects in the USA and Canada who have consumed venison from CWD-endemic areas utilizing the criteria and essays established in Aim 3. The findings from this proposal will greatly advance our understandings on the potential and characteristics of cervid prion transmission in humans, establish reliable essays for CWD zoonosis and potentially discover the first case(s) of CWD infection in humans.
Public Health Relevance There are significant and increasing human exposure to cervid prions because chronic wasting disease (CWD, a widespread and highly infectious prion disease among deer and elk in North America) continues spreading and consumption of venison remains popular, but our understanding on cervid-to-human prion transmission is still very limited, raising public health concerns. This proposal aims to define the zoonotic risks of cervid prions and set up and apply essays to detect CWD zoonosis using mouse models and in vitro methods. The findings will greatly expand our knowledge on the potentials and characteristics of cervid prion transmission in humans, establish reliable essays for such infections and may discover the first case(s) of CWD infection in humans.
Funding Agency Agency National Institute of Health (NIH) Institute National Institute of Neurological Disorders and Stroke (NINDS) Type Research Project (R01) Project # 1R01NS088604-01A1 Application # 9037884 Study Section Cellular and Molecular Biology of Neurodegeneration Study Section (CMND) Program Officer Wong, May Project Start 2015-09-30 Project End 2019-07-31 Budget Start 2015-09-30 Budget End 2016-07-31 Support Year 1 Fiscal Year 2015 Total Cost $337,507 Indirect Cost $118,756
snip...
Professor Kongs reply to me just this month about above grant study that has NOT been published in peer reveiw yet...
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Here is a brief summary of our findings:
snip...can't post, made a promise...tss
On Sat, Apr 3, 2021 at 12:19 PM Terry Singeltary <flounder9@verizon.net> wrote:
snip...
end...tss
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CWD ZOONOSIS THE FULL MONTY TO DATE
International Conference on Emerging Diseases, Outbreaks & Case Studies & 16th Annual Meeting on Influenza March 28-29, 2018 | Orlando, USA
Qingzhong Kong
Case Western Reserve University School of Medicine, USA
Zoonotic potential of chronic wasting disease prions from cervids
Chronic wasting disease (CWD) is the prion disease in cervids (mule deer, white-tailed deer, American elk, moose, and reindeer). It has become an epidemic in North America, and it has been detected in the Europe (Norway) since 2016. The widespread CWD and popular hunting and consumption of cervid meat and other products raise serious public health concerns, but questions remain on human susceptibility to CWD prions, especially on the potential difference in zoonotic potential among the various CWD prion strains. We have been working to address this critical question for well over a decade. We used CWD samples from various cervid species to inoculate transgenic mice expressing human or elk prion protein (PrP). We found infectious prions in the spleen or brain in a small fraction of CWD-inoculated transgenic mice expressing human PrP, indicating that humans are not completely resistant to CWD prions; this finding has significant ramifications on the public health impact of CWD prions. The influence of cervid PrP polymorphisms, the prion strain dependence of CWD-to-human transmission barrier, and the characterization of experimental human CWD prions will be discussed.
Speaker Biography Qingzhong Kong has completed his PhD from the University of Massachusetts at Amherst and Post-doctoral studies at Yale University. He is currently an Associate Professor of Pathology, Neurology and Regenerative Medicine. He has published over 50 original research papers in reputable journals (including Science Translational Medicine, JCI, PNAS and Cell Reports) and has been serving as an Editorial Board Member on seven scientific journals. He has multiple research interests, including public health risks of animal prions (CWD of cervids and atypical BSE of cattle), animal modeling of human prion diseases, mechanisms of prion replication and pathogenesis, etiology of sporadic Creutzfeldt-Jacob disease (CJD) in humans, normal cellular PrP in the biology and pathology of multiple brain and peripheral diseases, proteins responsible for the α-cleavage of cellular PrP, as well as gene therapy and DNA vaccination.
qxk2@case.edu
SUNDAY, JULY 25, 2021
North American and Norwegian Chronic Wasting Disease prions exhibit different potential for interspecies transmission and zoonotic risk
''Our data suggest that reindeer and red deer from Norway could be the most transmissible CWD prions to other mammals, whereas North American CWD prions were more prone to generate human prions in vitro.''
MONDAY, JULY 19, 2021
***> U Calgary researchers at work on a vaccine against a fatal infectious disease affecting deer and potentially people
Prion Conference 2018 Abstracts
BSE aka MAD COW DISEASE, was first discovered in 1984, and it took until 1995 to finally admit that BSE was causing nvCJD, the rest there is history, but that science is still evolving i.e. science now shows that indeed atypical L-type BSE, atypical Nor-98 Scrapie, and typical Scrapie are all zoonosis, zoonotic for humans, there from.
HOW long are we going to wait for Chronic Wasting Disease, CWD TSE Prion of Cervid, and zoonosis, zoonotic transmission to humans there from?
Studies have shown since 1994 that humans are susceptible to CWD TSE Prion, so, what's the hold up with making CWD a zoonotic zoonosis disease, the iatrogenic transmissions there from is not waiting for someone to make a decision.
Prion Conference 2018 Abstracts
P190 Human prion disease mortality rates by occurrence of chronic wasting disease in free ranging cervids, United States
Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1)
(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.
Background
Chronic wasting disease (CWD) is a prion disease of deer and elk that has been identified in free ranging cervids in 23 US states. While there is currently no epidemiological evidence for zoonotic transmission through the consumption of contaminated venison, studies suggest the CWD agent can cross the species barrier in experimental models designed to closely mimic humans. We compared rates of human prion disease in states with and without CWD to examine the possibility of undetermined zoonotic transmission.
Methods
Death records from the National Center for Health Statistics, case records from the National Prion Disease Pathology Surveillance Center, and additional state case reports were combined to create a database of human prion disease cases from 2003-2015. Identification of CWD in each state was determined through reports of positive CWD tests by state wildlife agencies. Age- and race-adjusted mortality rates for human prion disease, excluding cases with known etiology, were determined for four categories of states based on CWD occurrence: highly endemic (>16 counties with CWD identified in free-ranging cervids); moderately endemic (3-10 counties with CWD); low endemic (1-2 counties with CWD); and no CWD states. States were counted as having no CWD until the year CWD was first identified. Analyses stratified by age, sex, and time period were also conducted to focus on subgroups for which zoonotic transmission would be more likely to be detected: cases <55 years old, male sex, and the latter half of the study (2010-2015).
Results
Highly endemic states had a higher rate of prion disease mortality compared to non-CWD states (rate ratio [RR]: 1.12, 95% confidence interval [CI] = 1.01 - 1.23), as did low endemic states (RR: 1.15, 95% CI = 1.04 - 1.27). Moderately endemic states did not have an elevated mortality rate (RR: 1.05, 95% CI = 0.93 - 1.17). In age-stratified analyses, prion disease mortality rates among the <55 year old population were elevated for moderately endemic states (RR: 1.57, 95% CI = 1.10 – 2.24) while mortality rates were elevated among those ≥55 for highly endemic states (RR: 1.13, 95% CI = 1.02 - 1.26) and low endemic states (RR: 1.16, 95% CI = 1.04 - 1.29). In other stratified analyses, prion disease mortality rates for males were only elevated for low endemic states (RR: 1.27, 95% CI = 1.10 - 1.48), and none of the categories of CWD-endemic states had elevated mortality rates for the latter time period (2010-2015).
Conclusions
While higher prion disease mortality rates in certain categories of states with CWD in free-ranging cervids were noted, additional stratified analyses did not reveal markedly elevated rates for potentially sensitive subgroups that would be suggestive of zoonotic transmission. Unknown confounding factors or other biases may explain state-by-state differences in prion disease mortality.
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P172 Peripheral Neuropathy in Patients with Prion Disease
Wang H(1), Cohen M(1), Appleby BS(1,2)
(1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio.
Prion disease is a fatal progressive neurodegenerative disease due to deposition of an abnormal protease-resistant isoform of prion protein. Typical symptoms include rapidly progressive dementia, myoclonus, visual disturbance and hallucinations. Interestingly, in patients with prion disease, the abnormal protein canould also be found in the peripheral nervous system. Case reports of prion deposition in peripheral nerves have been reported. Peripheral nerve involvement is thought to be uncommon; however, little is known about the exact prevalence and features of peripheral neuropathy in patients with prion disease.
We reviewed autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017. We collected information regarding prion protein diagnosis, demographics, comorbidities, clinical symptoms, physical exam, neuropathology, molecular subtype, genetics lab, brain MRI, image and EMG reports. Our study included 104 patients. Thirteen (12.5%) patients had either subjective symptoms or objective signs of peripheral neuropathy. Among these 13 patients, 3 had other known potential etiologies of peripheral neuropathy such as vitamin B12 deficiency or prior chemotherapy. Among 10 patients that had no other clear etiology, 3 (30%) had familial CJD. The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%). The Majority of cases wasere male (60%). Half of them had exposure to wild game. The most common subjective symptoms were tingling and/or numbness of distal extremities. The most common objective finding was diminished vibratory sensation in the feet. Half of them had an EMG with the findings ranging from fasciculations to axonal polyneuropathy or demyelinating polyneuropathy.
Our study provides an overview of the pattern of peripheral neuropathy in patients with prion disease. Among patients with peripheral neuropathy symptoms or signs, majority has polyneuropathy. It is important to document the baseline frequency of peripheral neuropathy in prion diseases as these symptoms may become important when conducting surveillance for potential novel zoonotic prion diseases.
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P177 PrP plaques in methionine homozygous Creutzfeldt-Jakob disease patients as a potential marker of iatrogenic transmission
Abrams JY (1), Schonberger LB (1), Cali I (2), Cohen Y (2), Blevins JE (2), Maddox RA (1), Belay ED (1), Appleby BS (2), Cohen ML (2)
(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.
Background
Sporadic Creutzfeldt-Jakob disease (CJD) is widely believed to originate from de novo spontaneous conversion of normal prion protein (PrP) to its pathogenic form, but concern remains that some reported sporadic CJD cases may actually be caused by disease transmission via iatrogenic processes. For cases with methionine homozygosity (CJD-MM) at codon 129 of the PRNP gene, recent research has pointed to plaque-like PrP deposition as a potential marker of iatrogenic transmission for a subset of cases. This phenotype is theorized to originate from specific iatrogenic source CJD types that comprise roughly a quarter of known CJD cases.
Methods
We reviewed scientific literature for studies which described PrP plaques among CJD patients with known epidemiological links to iatrogenic transmission (receipt of cadaveric human grown hormone or dura mater), as well as in cases of reported sporadic CJD. The presence and description of plaques, along with CJD classification type and other contextual factors, were used to summarize the current evidence regarding plaques as a potential marker of iatrogenic transmission. In addition, 523 cases of reported sporadic CJD cases in the US from January 2013 through September 2017 were assessed for presence of PrP plaques.
Results
We identified four studies describing 52 total cases of CJD-MM among either dura mater recipients or growth hormone recipients, of which 30 were identified as having PrP plaques. While sporadic cases were not generally described as having plaques, we did identify case reports which described plaques among sporadic MM2 cases as well as case reports of plaques exclusively in white matter among sporadic MM1 cases. Among the 523 reported sporadic CJD cases, 0 of 366 MM1 cases had plaques, 2 of 48 MM2 cases had kuru plaques, and 4 of 109 MM1+2 cases had either kuru plaques or both kuru and florid plaques. Medical chart review of the six reported sporadic CJD cases with plaques did not reveal clinical histories suggestive of potential iatrogenic transmission.
Conclusions
PrP plaques occur much more frequently for iatrogenic CJD-MM cases compared to sporadic CJDMM cases. Plaques may indicate iatrogenic transmission for CJD-MM cases without a type 2 Western blot fragment. The study results suggest the absence of significant misclassifications of iatrogenic CJD as sporadic. To our knowledge, this study is the first to describe grey matter kuru plaques in apparently sporadic CJD-MM patients with a type 2 Western blot fragment.
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P180 Clinico-pathological analysis of human prion diseases in a brain bank series
Ximelis T (1), Aldecoa I (1,2), Molina-Porcel L (1,3), Grau-Rivera O (4), Ferrer I (5), Nos C (6), Gelpi E (1,7), Sánchez-Valle R (1,4)
(1) Neurological Tissue Bank of the Biobanc-Hospital ClÃnic-IDIBAPS, Barcelona, Spain (2) Pathological Service of Hospital ClÃnic de Barcelona, Barcelona, Spain (3) EAIA Trastorns Cognitius, Centre Emili Mira, Parc de Salut Mar, Barcelona, Spain (4) Department of Neurology of Hospital ClÃnic de Barcelona, Barcelona, Spain (5) Institute of Neuropathology, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Barcelona (6) General subdirectorate of Surveillance and Response to Emergencies in Public Health, Department of Public Health in Catalonia, Barcelona, Spain (7) Institute of Neurology, Medical University of Vienna, Vienna, Austria.
Background and objective:
The Neurological Tissue Bank (NTB) of the Hospital Clínic-Institut d‘Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain is the reference center in Catalonia for the neuropathological study of prion diseases in the region since 2001. The aim of this study is to analyse the characteristics of the confirmed prion diseases registered at the NTB during the last 15 years.
Methods:
We reviewed retrospectively all neuropathologically confirmed cases registered during the period January 2001 to December 2016.
Results:
176 cases (54,3% female, mean age: 67,5 years and age range: 25-86 years) of neuropathological confirmed prion diseases have been studied at the NTB. 152 cases corresponded to sporadic Creutzfeldt-Jakob disease (sCJD), 10 to genetic CJD, 10 to Fatal Familial Insomnia, 2 to GerstmannSträussler-Scheinker disease, and 2 cases to variably protease-sensitive prionopathy (VPSPr). Within sCJD subtypes the MM1 subtype was the most frequent, followed by the VV2 histotype.
Clinical and neuropathological diagnoses agreed in 166 cases (94%). The clinical diagnosis was not accurate in 10 patients with definite prion disease: 1 had a clinical diagnosis of Fronto-temporal dementia (FTD), 1 Niemann-Pick‘s disease, 1 Lewy Body‘s Disease, 2 Alzheimer‘s disease, 1 Cortico-basal syndrome and 2 undetermined dementia. Among patients with VPSPr, 1 had a clinical diagnosis of Amyotrophic lateral sclerosis (ALS) and the other one with FTD.
Concomitant pathologies are frequent in older age groups, mainly AD neuropathological changes were observed in these subjects.
Discussion:
A wide spectrum of human prion diseases have been identified in the NTB being the relative frequencies and main characteristics like other published series. There is a high rate of agreement between clinical and neuropathological diagnoses with prion diseases. These findings show the importance that public health has given to prion diseases during the past 15 years. Continuous surveillance of human prion disease allows identification of new emerging phenotypes. Brain tissue samples from these donors are available to the scientific community. For more information please visit:
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P192 Prion amplification techniques for the rapid evaluation of surface decontamination procedures
Bruyere-Ostells L (1), Mayran C (1), Belondrade M (1), Boublik Y (2), Haïk S (3), Fournier-Wirth C (1), Nicot S (1), Bougard D (1)
(1) Pathogenesis and control of chronic infections, Etablissement Français du Sang, Inserm, Université de Montpellier, Montpellier, France. (2) Centre de Recherche en Biologie cellulaire de Montpellier, CNRS, Université de Montpellier, Montpellier, France. (3) Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Université Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France.
Aims:
Transmissible Spongiform Encephalopathies (TSE) or prion diseases are a group of incurable and always fatal neurodegenerative disorders including Creutzfeldt-Jakob diseases (CJD) in humans. These pathologies include sporadic (sCJD), genetic and acquired (variant CJD) forms. By the past, sCJD and vCJD were transmitted by different prion contaminated biological materials to patients resulting in more than 400 iatrogenic cases (iCJD). The atypical nature and the biochemical properties of the infectious agent, formed by abnormal prion protein or PrPTSE, make it particularly resistant to conventional decontamination procedures. In addition, PrPTSE is widely distributed throughout the organism before clinical onset in vCJD and can also be detected in some peripheral tissues in sporadic CJD. Risk of iatrogenic transmission of CJD by contaminated medical device remains thus a concern for healthcare facilities. Bioassay is the gold standard method to evaluate the efficacy of prion decontamination procedures but is time-consuming and expensive. Here, we propose to compare in vitro prion amplification techniques: Protein Misfolding Cyclic Amplification (PMCA) and Real-Time Quaking Induced Conversion (RT-QuIC) for the detection of residual prions on surface after decontamination.
Methods:
Stainless steel wires, by mimicking the surface of surgical instruments, were proposed as a carrier model of prions for inactivation studies. To determine the sensitivity of the two amplification techniques on wires (Surf-PMCA and Surf-QuIC), steel wires were therefore contaminated with serial dilutions of brain homogenates (BH) from a 263k infected hamster and from a patient with sCJD (MM1 subtype). We then compared the different standard decontamination procedures including partially and fully efficient treatments by detecting the residual seeding activity on 263K and sCJD contaminated wires. We completed our study by the evaluation of marketed reagents endorsed for prion decontamination.
Results:
The two amplification techniques can detect minute quantities of PrPTSE adsorbed onto a single wire. 8/8 wires contaminated with a 10-6 dilution of 263k BH and 1/6 with the 10-8 dilution are positive with Surf-PMCA. Similar performances were obtained with Surf-QuIC on 263K: 10/16 wires contaminated with 10-6 dilution and 1/8 wires contaminated with 10-8 dilution are positive. Regarding the human sCJD-MM1 prion, Surf-QuIC allows us to detect 16/16 wires contaminated with 10-6 dilutions and 14/16 with 10-7 . Results obtained after decontamination treatments are very similar between 263K and sCJD prions. Efficiency of marketed treatments to remove prions is lower than expected.
Conclusions:
Surf-PMCA and Surf-QuIC are very sensitive methods for the detection of prions on wires and could be applied to prion decontamination studies for rapid evaluation of new treatments. Sodium hypochlorite is the only product to efficiently remove seeding activity of both 263K and sCJD prions.
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WA2 Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice
Schatzl HM (1, 2), Hannaoui S (1, 2), Cheng Y-C (1, 2), Gilch S (1, 2), Beekes M (3), SchulzSchaeffer W (4), Stahl-Hennig C (5) and Czub S (2, 6)
(1) University of Calgary, Calgary Prion Research Unit, Calgary, Canada (2) University of Calgary, Faculty of Veterinary Medicine, Calgary, Canada, (3) Robert Koch Institute, Berlin, Germany, (4) University of Homburg/Saar, Homburg, Germany, (5) German Primate Center, Goettingen, Germany, (6) Canadian Food Inspection Agency (CFIA), Lethbridge, Canada.
To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years. After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were found in spinal cord and brain of euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and preclinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles. Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate. The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology. Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP. The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.
See also poster P103
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.
=====
WA16 Monitoring Potential CWD Transmission to Humans
Belay ED
Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA.
The spread of chronic wasting disease (CWD) in animals has raised concerns about increasing human exposure to the CWD agent via hunting and venison consumption, potentially facilitating CWD transmission to humans. Several studies have explored this possibility, including limited epidemiologic studies, in vitro experiments, and laboratory studies using various types of animal models. Most human exposures to the CWD agent in the United States would be expected to occur in association with deer and elk hunting in CWD-endemic areas. The Centers for Disease Control and Prevention (CDC) collaborated with state health departments in Colorado, Wisconsin, and Wyoming to identify persons at risk of CWD exposure and to monitor their vital status over time. Databases were established of persons who hunted in Colorado and Wyoming and those who reported consumption of venison from deer that later tested positive in Wisconsin. Information from the databases is periodically cross-checked with mortality data to determine the vital status and causes of death for deceased persons. Long-term follow-up of these hunters is needed to assess their risk of development of a prion disease linked to CWD exposure.
=====
P166 Characterization of CJD strain profiles in venison consumers and non-consumers from Alberta and Saskatchewan
Stephanie Booth (1,2), Lise Lamoureux (1), Debra Sorensen (1), Jennifer L. Myskiw (1,2), Megan Klassen (1,2), Michael Coulthart (3), Valerie Sim (4)
(1) Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg (2) Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg (3) Canadian CJD Surveillance System, Public Health Agency of Canada, Ottawa (4) Division of Neurology, Department of Medicine Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton.
Chronic wasting disease (CWD) is spreading rapidly through wild cervid populations in the Canadian provinces of Alberta and Saskatchewan. While this has implications for tourism and hunting, there is also concern over possible zoonotic transmission to humans who eat venison from infected deer. Whilst there is no evidence of any human cases of CWD to date, the Canadian CJD Surveillance System (CJDSS) in Canada is staying vigilant. When variant CJD occurred following exposure to BSE, the unique biochemical fingerprint of the pathologic PrP enabled a causal link to be confirmed. However, we cannot be sure what phenotype human CWD prions would present with, or indeed, whether this would be distinct from that see in sporadic CJD. Therefore we are undertaking a systematic analysis of the molecular diversity of CJD cases of individuals who resided in Alberta and Saskatchewan at their time of death comparing venison consumers and non-consumers, using a variety of clinical, imaging, pathological and biochemical markers. Our initial objective is to develop novel biochemical methodologies that will extend the baseline glycoform and genetic polymorphism typing that is already completed by the CJDSS. Firstly, we are reviewing MRI, EEG and pathology information from over 40 cases of CJD to select clinically affected areas for further investigation. Biochemical analysis will include assessment of the levels of protease sensitive and resistant prion protein, glycoform typing using 2D gel electrophoresis, testing seeding capabilities and kinetics of aggregation by quaking-induced conversion, and determining prion oligomer size distributions with asymmetric flow field fractionation with in-line light scattering. Progress and preliminary data will be presented. Ultimately, we intend to further define the relationship between PrP structure and disease phenotype and establish a baseline for the identification of future atypical CJD cases that may arise as a result of exposure to CWD.
=====
Source Prion Conference 2018 Abstracts
Volume 24, Number 8—August 2018
Research Susceptibility of Human Prion Protein to Conversion by Chronic Wasting Disease Prions
Marcelo A. BarriaComments to Author , Adriana Libori, Gordon Mitchell, and Mark W. Head Author affiliations: National CJD Research and Surveillance Unit, University of Edinburgh, Edinburgh, Scotland, UK (M.A. Barria, A. Libori, M.W. Head); National and OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada (G. Mitchell)
Abstract Chronic wasting disease (CWD) is a contagious and fatal neurodegenerative disease and a serious animal health issue for deer and elk in North America. The identification of the first cases of CWD among free-ranging reindeer and moose in Europe brings back into focus the unresolved issue of whether CWD can be zoonotic like bovine spongiform encephalopathy. We used a cell-free seeded protein misfolding assay to determine whether CWD prions from elk, white-tailed deer, and reindeer in North America can convert the human prion protein to the disease-associated form. We found that prions can convert, but the efficiency of conversion is affected by polymorphic variation in the cervid and human prion protein genes. In view of the similarity of reindeer, elk, and white-tailed deer in North America to reindeer, red deer, and roe deer, respectively, in Europe, a more comprehensive and thorough assessment of the zoonotic potential of CWD might be warranted.
snip...
Discussion Characterization of the transmission properties of CWD and evaluation of their zoonotic potential are important for public health purposes. Given that CWD affects several members of the family Cervidae, it seems reasonable to consider whether the zoonotic potential of CWD prions could be affected by factors such as CWD strain, cervid species, geographic location, and Prnp–PRNP polymorphic variation. We have previously used an in vitro conversion assay (PMCA) to investigate the susceptibility of the human PrP to conversion to its disease-associated form by several animal prion diseases, including CWD (15,16,22). The sensitivity of our molecular model for the detection of zoonotic conversion depends on the combination of 1) the action of proteinase K to degrade the abundant human PrPC that constitutes the substrate while only N terminally truncating any human PrPres produced and 2) the presence of the 3F4 epitope on human but not cervid PrP. In effect, this degree of sensitivity means that any human PrPres formed during the PMCA reaction can be detected down to the limit of Western blot sensitivity. In contrast, if other antibodies that detect both cervid and human PrP are used, such as 6H4, then newly formed human PrPres must be detected as a measurable increase in PrPres over the amount remaining in the reaction product from the cervid seed. Although best known for the efficient amplification of prions in research and diagnostic contexts, the variation of the PMCA method employed in our study is optimized for the definitive detection of zoonotic reaction products of inherently inefficient conversion reactions conducted across species barriers. By using this system, we previously made and reported the novel observation that elk CWD prions could convert human PrPC from human brain and could also convert recombinant human PrPC expressed in transgenic mice and eukaryotic cell cultures (15).
A previous publication suggested that mule deer PrPSc was unable to convert humanized transgenic substrate in PMCA assays (23) and required a further step of in vitro conditioning in deer substrate PMCA before it was able to cross the deer–human molecular barrier (24). However, prions from other species, such as elk (15) and reindeer affected by CWD, appear to be compatible with the human protein in a single round of amplification (as shown in our study). These observations suggest that different deer species affected by CWD could present differing degrees of the olecular compatibility with the normal form of human PrP.
The contribution of the polymorphism at codon 129 of the human PrP gene has been extensively studied and is recognized as a risk factor for Creutzfeldt-Jakob disease (4). In cervids, the equivalent codon corresponds to the position 132 encoding methionine or leucine. This polymorphism in the elk gene has been shown to play an important role in CWD susceptibility (25,26). We have investigated the effect of this cervid Prnp polymorphism on the conversion of the humanized transgenic substrate according to the variation in the equivalent PRNP codon 129 polymorphism. Interestingly, only the homologs methionine homozygous seed–substrate reactions could readily convert the human PrP, whereas the heterozygous elk PrPSc was unable to do so, even though comparable amounts of PrPres were used to seed the reaction. In addition, we observed only low levels of human PrPres formation in the reactions seeded with the homozygous methionine (132 MM) and the heterozygous (132 ML) seeds incubated with the other 2 human polymorphic substrates (129 MV and 129 VV). The presence of the amino acid leucine at position 132 of the elk Prnp gene has been attributed to a lower degree of prion conversion compared with methionine on the basis of experiments in mice made transgenic for these polymorphic variants (26). Considering the differences observed for the amplification of the homozygous human methionine substrate by the 2 polymorphic elk seeds (MM and ML), reappraisal of the susceptibility of human PrPC by the full range of cervid polymorphic variants affected by CWD would be warranted.
In light of the recent identification of the first cases of CWD in Europe in a free-ranging reindeer (R. tarandus) in Norway (2), we also decided to evaluate the in vitro conversion potential of CWD in 2 experimentally infected reindeer (18). Formation of human PrPres was readily detectable after a single round of PMCA, and in all 3 humanized polymorphic substrates (MM, MV, and VV). This finding suggests that CWD prions from reindeer could be more compatible with human PrPC generally and might therefore present a greater risk for zoonosis than, for example, CWD prions from white-tailed deer. A more comprehensive comparison of CWD in the affected species, coupled with the polymorphic variations in the human and deer PRNP–Prnp genes, in vivo and in vitro, will be required before firm conclusions can be drawn. Analysis of the Prnp sequence of the CWD reindeer in Norway was reported to be identical to the specimens used in our study (2). This finding raises the possibility of a direct comparison of zoonotic potential between CWD acquired in the wild and that produced in a controlled laboratory setting. (Table).
The prion hypothesis proposes that direct molecular interaction between PrPSc and PrPC is necessary for conversion and prion replication. Accordingly, polymorphic variants of the PrP of host and agent might play a role in determining compatibility and potential zoonotic risk. In this study, we have examined the capacity of the human PrPC to support in vitro conversion by elk, white-tailed deer, and reindeer CWD PrPSc. Our data confirm that elk CWD prions can convert the human PrPC, at least in vitro, and show that the homologous PRNP polymorphisms at codon 129 and 132 in humans and cervids affect conversion efficiency. Other species affected by CWD, particularly caribou or reindeer, also seem able to convert the human PrP. It will be important to determine whether other polymorphic variants found in other CWD-affected Cervidae or perhaps other factors (17) exert similar effects on the ability to convert human PrP and thus affect their zoonotic potential.
Dr. Barria is a research scientist working at the National CJD Research and Surveillance Unit, University of Edinburgh. His research has focused on understanding the molecular basis of a group of fatal neurologic disorders called prion diseases.
Acknowledgments We thank Aru Balachandran for originally providing cervid brain tissues, Abigail Diack and Jean Manson for providing mouse brain tissue, and James Ironside for his critical reading of the manuscript at an early stage.
This report is independent research commissioned and funded by the United Kingdom’s Department of Health Policy Research Programme and the Government of Scotland. The views expressed in this publication are those of the authors and not necessarily those of the Department of Health or the Government of Scotland.
Author contributions: The study was conceived and designed by M.A.B. and M.W.H. The experiments were conducted by M.A.B. and A.L. Chronic wasting disease brain specimens were provided by G.M. The manuscript was written by M.A.B. and M.W.H. All authors contributed to the editing and revision of the manuscript.
Prion 2017 Conference Abstracts
First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress
Stefanie Czub1, Walter Schulz-Schaeffer2, Christiane Stahl-Hennig3, Michael Beekes4, Hermann Schaetzl5 and Dirk Motzkus6 1 University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency; 2Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes; 3 Deutsches Primaten Zentrum/Goettingen; 4 Robert-Koch-Institut Berlin; 5 University of Calgary Faculty of Veterinary Medicine; 6 presently: Boehringer Ingelheim Veterinary Research Center; previously: Deutsches Primaten Zentrum/Goettingen
This is a progress report of a project which started in 2009.
21 cynomolgus macaques were challenged with characterized CWD material from white-tailed deer (WTD) or elk by intracerebral (ic), oral, and skin exposure routes. Additional blood transfusion experiments are supposed to assess the CWD contamination risk of human blood product. Challenge materials originated from symptomatic cervids for ic, skin scarification and partially per oral routes (WTD brain). Challenge material for feeding of muscle derived from preclinical WTD and from preclinical macaques for blood transfusion experiments. We have confirmed that the CWD challenge material contained at least two different CWD agents (brain material) as well as CWD prions in muscle-associated nerves. Here we present first data on a group of animals either challenged ic with steel wires or per orally and sacrificed with incubation times ranging from 4.5 to 6.9 years at postmortem. Three animals displayed signs of mild clinical disease, including anxiety, apathy, ataxia and/or tremor. In four animals wasting was observed, two of those had confirmed diabetes. All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals. Protein misfolding cyclic amplification (PMCA), real-time quaking-induced conversion (RT-QuiC) and PET-blot assays to further substantiate these findings are on the way, as well as bioassays in bank voles and transgenic mice. At present, a total of 10 animals are sacrificed and read-outs are ongoing. Preclinical incubation of the remaining macaques covers a range from 6.4 to 7.10 years. Based on the species barrier and an incubation time of > 5 years for BSE in macaques and about 10 years for scrapie in macaques, we expected an onset of clinical disease beyond 6 years post inoculation.
PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS ABSTRACTS REFERENCE
8. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
SATURDAY, FEBRUARY 23, 2019
Chronic Wasting Disease CWD TSE Prion and THE FEAST 2003 CDC an updated review of the science 2019
TUESDAY, NOVEMBER 04, 2014
Six-year follow-up of a point-source exposure to CWD contaminated venison in an Upstate New York community: risk behaviours and health outcomes 2005–2011 Authors, though, acknowledged the study was limited in geography and sample size and so it couldn't draw a conclusion about the risk to humans. They recommended more study. Dr. Ermias Belay was the report's principal author but he said New York and Oneida County officials are following the proper course by not launching a study. "There's really nothing to monitor presently. No one's sick," Belay said, noting the disease's incubation period in deer and elk is measured in years. "
Transmission Studies Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}....TSS resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.
snip....
Prion Infectivity in Fat of Deer with Chronic Wasting Disease▿
Brent Race#, Kimberly Meade-White#, Richard Race and Bruce Chesebro* + Author Affiliations In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species.
http://jvi.asm.org/content/83/18/9608.full Prions in Skeletal Muscles of Deer with Chronic Wasting Disease Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure.
*** now, let’s see what the authors said about this casual link, personal communications years ago, and then the latest on the zoonotic potential from CWD to humans from the TOKYO PRION 2016 CONFERENCE.
see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ????
“Our conclusion stating that we found no strong evidence of CWD transmission to humans”
From: TSS Subject: CWD aka MAD DEER/ELK TO HUMANS ???
Date: September 30, 2002 at 7:06 am PST
From: "Belay, Ermias"
To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"
Sent: Monday, September 30, 2002 9:22 AM
Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Dear Sir/Madam, In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091).
Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.
Ermias Belay, M.D. Centers for Disease Control and Prevention
-----Original Message----- From:
Sent: Sunday, September 29, 2002 10:15 AM
To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV
Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Sunday, November 10, 2002 6:26 PM .......snip........end..............TSS
Thursday, April 03, 2008
A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.
snip... *** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,
snip... full text ;
> However, to date, no CWD infections have been reported in people.
sporadic, spontaneous CJD, 85%+ of all human TSE, did not just happen. never in scientific literature has this been proven. if one looks up the word sporadic or spontaneous at pubmed, you will get a laundry list of disease that are classified in such a way;
sporadic = 54,983 hits
spontaneous = 325,650 hits
key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD.
SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
> However, to date, no CWD infections have been reported in people. key word here is ‘reported’. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can’t, and it’s as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it’s being misdiagnosed as sporadic CJD. …terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
CWD TSE PRION AND ZOONOTIC, ZOONOSIS, FACTORS
Subject: Re: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY
Date: Fri, 18 Oct 2002 23:12:22 +0100
From: Steve Dealler
Reply-To: Bovine Spongiform Encephalopathy Organization: Netscape Online member
To: BSE-L@ References:
Dear Terry,
An excellent piece of review as this literature is desperately difficult to get back from Government sites.
What happened with the deer was that an association between deer meat eating and sporadic CJD was found in about 1993. The evidence was not great but did not disappear after several years of asking CJD cases what they had eaten. I think that the work into deer disease largely stopped because it was not helpful to the UK industry...and no specific cases were reported. Well, if you dont look adequately like they are in USA currenly then you wont find any!
Steve Dealler
====
''The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).''
CREUTZFELDT JAKOB DISEASE SURVEILLANCE IN THE UNITED KINGDOM THIRD ANNUAL REPORT AUGUST 1994
Consumption of venison and veal was much less widespread among both cases and controls. For both of these meats there was evidence of a trend with increasing frequency of consumption being associated with increasing risk of CJD. (not nvCJD, but sporadic CJD...tss) These associations were largely unchanged when attention was restricted to pairs with data obtained from relatives. ...
Table 9 presents the results of an analysis of these data.
There is STRONG evidence of an association between ‘’regular’’ veal eating and risk of CJD (p = .0.01).
Individuals reported to eat veal on average at least once a year appear to be at 13 TIMES THE RISK of individuals who have never eaten veal.
There is, however, a very wide confidence interval around this estimate. There is no strong evidence that eating veal less than once per year is associated with increased risk of CJD (p = 0.51).
The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).
There is some evidence that risk of CJD INCREASES WITH INCREASING FREQUENCY OF LAMB EATING (p = 0.02).
The evidence for such an association between beef eating and CJD is weaker (p = 0.14). When only controls for whom a relative was interviewed are included, this evidence becomes a little STRONGER (p = 0.08).
snip...
It was found that when veal was included in the model with another exposure, the association between veal and CJD remained statistically significant (p = < 0.05 for all exposures), while the other exposures ceased to be statistically significant (p = > 0.05).
snip...
In conclusion, an analysis of dietary histories revealed statistical associations between various meats/animal products and INCREASED RISK OF CJD. When some account was taken of possible confounding, the association between VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS STATISTICALLY. ...
snip...
In the study in the USA, a range of foodstuffs were associated with an increased risk of CJD, including liver consumption which was associated with an apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3 studies in relation to this particular dietary factor, the risk of liver consumption became non-significant with an odds ratio of 1.2 (PERSONAL COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (???...TSS)
snip...see full report ;
http://web.archive.org/web/20090506050043/http://www.bseinquiry.gov.uk/files/yb/1994/08/00004001.pdf
http://web.archive.org/web/20090506050007/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf
http://web.archive.org/web/20090506050244/http://www.bseinquiry.gov.uk/files/yb/1994/07/00001001.pdf
Stephen Dealler is a consultant medical microbiologist deal@airtime.co.uk
BSE Inquiry Steve Dealler
Management In Confidence
BSE: Private Submission of Bovine Brain Dealler
snip...see full text;
MONDAY, FEBRUARY 25, 2019
***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019
***> ''The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).''
***> In conclusion, sensory symptoms and loss of reflexes in Gerstmann-Sträussler-Scheinker syndrome can be explained by neuropathological changes in the spinal cord. We conclude that the sensory symptoms and loss of lower limb reflexes in Gerstmann-Sträussler-Scheinker syndrome is due to pathology in the caudal spinal cord. <***
***> The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.<***
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***
***> All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals.<***
***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids.'' Scientific opinion on chronic wasting disease (II) <***
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***
Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
Experimental Oronasal Inoculation of the Chronic Wasting Disease Agent into White Tailed Deer
Author list: Sarah Zurbuchena,b , S. Jo Moorea,b , Jifeng Biana , Eric D. Cassmanna , and Justin J. Greenleea .
a. Virus and Prion Research Unit, National Animal Disease Center, ARS, United States Department of Agriculture, Ames, IA, US
b. Oak Ridge Institute for Science and Education (ORISE), U.S. Department of Energy, Oak Ridge, TN, United States
Aims: The purpose of this experiment was to determine whether white-tailed deer (WTD) are susceptible to inoculation of chronic wasting disease (CWD) via oronasal exposure.
Materials and methods: Six male, neutered WTD were oronasally inoculated with brainstem material (10% w/v) from a CWD-positive wild-type WTD. The genotypes of five inoculated deer were Q95/G96 (wild-type). One inoculated deer was homozygous S at codon 96 (96SS). Cervidized (Tg12; M132 elk PrP) mice were inoculated with 1% w/v brainstem homogenate from either a 96GG WTD (n=10) or the 96SS WTD (n=10).
Results: All deer developed characteristic clinical signs of CWD including weight loss, regurgitation, and ataxia. The 96SS individual had a prolonged disease course and incubation period compared to the other deer. Western blots of the brainstem on all deer yielded similar molecular profiles. All deer had widespread lymphoid distribution of PrPCWD and neuropathologic lesions associated with transmissible spongiform encephalopathies. Both groups of mice had a 100% attack rate and developed clinical signs, including loss of body condition, ataxia, and loss of righting reflex. Mice inoculated with material from the 96SS deer had a significantly shorter incubation period than mice inoculated with material from 96GG deer (Welch two sample T-test, P<0.05). Serial dilutions of each inocula suggests that differences in incubation period were not due to a greater concentration of PrPCWD in the 96SS inoculum. Molecular profiles from western blot of brain homogenates from mice appeared similar regardless of inoculum and appear similar to those of deer used for inoculum.
Conclusions: This study characterizes the lesions and clinical course of CWD in WTD inoculated in a similar manner to natural conditions. It supports previous findings that 96SS deer have a prolonged disease course. Further, it describes a first pass of inoculum from a 96SS deer in cervidized mice which shortened the incubation period.
Funded by: This research was funded in its entirety by congressionally appropriated funds to the United States Department of Agriculture, Agricultural Research Service. The funders of the work did not influence study design, data collection, analysis, decision to publish, or preparation of the manuscript.
Acknowledgement: We thank Ami Frank and Kevin Hassall for their technical contributions to this project.
Price of TSE Prion Poker goes up substantially, all you cattle ranchers and such, better pay close attention here...terry
Transmission of the chronic wasting disease agent from elk to cattle after oronasal exposure
Justin Greenlee, Jifeng Bian, Zoe Lambert, Alexis Frese, and Eric Cassmann Virus and Prion Research Unit, National Animal Disease Center, USDA-ARS, Ames, IA, USA
Aims: The purpose of this study was to determine the susceptibility of cattle to chronic wasting disease agent from elk.
Conclusions: Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material.
"Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material."
=====end
Strain characterization of chronic wasting disease in bovine-PrP transgenic mice
Conclusions: Altogether, these results exhibit the diversity of CWD strains present in the panel of CWD isolates and the ability of at least some CWD isolates to infect bovine species. Cattle being one of the most important farming species, this ability represents a potential threat to both animal and human health, and consequently deserves further study.
"Altogether, these results exhibit the diversity of CWD strains present in the panel of CWD isolates and the ability of at least some CWD isolates to infect bovine species. Cattle being one of the most important farming species, this ability represents a potential threat to both animal and human health, and consequently deserves further study."
=====end
CWD TRANSMITS BY ORAL ROUTES TO MACAQUES, CATTLE, SHEEP, PIGS, AND CERVID...BSE Feed Regulation (21 CFR 589.2000) mad cow feed ban does not stop all that!
CWD transmits to cervid by oral routes with as little as 300NG!
PLoS One. 2020; 15(8): e0237410.
Published online 2020 Aug 20. doi: 10.1371/journal.pone.0237410
PMCID: PMC7446902
PMID: 32817706
Very low oral exposure to prions of brain or saliva origin can transmit chronic wasting disease
We orally inoculated white-tailed deer with either single or multiple divided doses of prions of brain or saliva origin and monitored infection by serial longitudinal tissue biopsies spanning over two years. We report that oral exposure to as little as 300 nanograms (ng) of CWD-positive brain or to saliva containing seeding activity equivalent to 300 ng of CWD-positive brain, were sufficient to transmit CWD disease.
snip...
These studies suggest that the CWD minimum infectious dose approximates 100 to 300 ng CWD-positive brain (or saliva equivalent), and that CWD infection appears to conform more with a threshold than a cumulative dose dynamic.
How in the hell do you make a complete recall of 27,694,240 lbs of feed that was manufactured from materials that may have been contaminated with mammalian protein, in one state, Michigan, 2006? Wonder how much was fed out?
RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINE -- CLASS II
______________________________
PRODUCT
a) CO-OP 32% Sinking Catfish, Recall # V-100-6; b) Performance Sheep Pell W/Decox/A/N, medicated, net wt. 50 lbs, Recall # V-101-6; c) Pro 40% Swine Conc Meal -- 50 lb, Recall # V-102-6; d) CO-OP 32% Sinking Catfish Food Medicated, Recall # V-103-6; e) "Big Jim’s" BBB Deer Ration, Big Buck Blend, Recall # V-104-6; f) CO-OP 40% Hog Supplement Medicated Pelleted, Tylosin 100 grams/ton, 50 lb. bag, Recall # V-105-6; g) Pig Starter Pell II, 18% W/MCDX Medicated 282020, Carbadox -- 0.0055%, Recall # V-106-6; h) CO-OP STARTER-GROWER CRUMBLES, Complete Feed for Chickens from Hatch to 20 Weeks, Medicated, Bacitracin Methylene Disalicylate, 25 and 50 Lbs, Recall # V-107-6; i) CO-OP LAYING PELLETS, Complete Feed for Laying Chickens, Recall # 108-6; j) CO-OP LAYING CRUMBLES, Recall # V-109-6; k) CO-OP QUAIL FLIGHT CONDITIONER MEDICATED, net wt 50 Lbs, Recall # V-110-6; l) CO-OP QUAIL STARTER MEDICATED, Net Wt. 50 Lbs, Recall # V-111-6; m) CO-OP QUAIL GROWER MEDICATED, 50 Lbs, Recall # V-112-6
CODE Product manufactured from 02/01/2005 until 06/06/2006
RECALLING FIRM/MANUFACTURER Alabama Farmers Cooperative, Inc., Decatur, AL, by telephone, fax, email and visit on June 9, 2006. FDA initiated recall is complete.
REASON Animal and fish feeds which were possibly contaminated with ruminant based protein not labeled as "Do not feed to ruminants".
VOLUME OF PRODUCT IN COMMERCE 125 tons
DISTRIBUTION AL and FL
______________________________
PRODUCT Bulk custom dairy feds manufactured from concentrates, Recall # V-113-6
CODE All dairy feeds produced between 2/1/05 and 6/16/06 and containing H. J. Baker recalled feed products.
RECALLING FIRM/MANUFACTURER Vita Plus Corp., Gagetown, MI, by visit beginning on June 21, 2006. Firm initiated recall is complete.
REASON The feed was manufactured from materials that may have been contaminated with mammalian protein.
VOLUME OF PRODUCT IN COMMERCE 27,694,240 lbs
DISTRIBUTION MI
______________________________
PRODUCT Bulk custom made dairy feed, Recall # V-114-6
CODE None
RECALLING FIRM/MANUFACTURER Burkmann Feeds LLC, Glasgow, KY, by letter on July 14, 2006. Firm initiated recall is ongoing.
REASON Custom made feeds contain ingredient called Pro-Lak, which may contain ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE ?????
DISTRIBUTION KY
END OF ENFORCEMENT REPORT FOR AUGUST 2, 2006
###
Friday, December 14, 2012
DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012
snip.....
In the USA, under the Food and Drug Administration's BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system. However, this recommendation is guidance and not a requirement by law. Animals considered at high risk for CWD include:
1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and
2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal.
Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants.
The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES.
It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011.
Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB.
There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products.
snip.....
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer and Elk in Animal Feed
PUBLIC SUBMISSION
Comment from Terry Singeltary Sr.
Posted by the Food and Drug Administration on May 17, 2016 Comment
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer and Elk in Animal Feed Singeltary Submission
Contains Nonbinding Recommendations
2
Guidance for Industry
Use of Material from Deer and Elk
in Animal Feed
This guidance represents the current thinking of the Food and Drug Administration (FDA or Agency) on this topic. It does not establish any rights for any person and is not binding on FDA or the public. You can use an alternative approach if it satisfies the requirements of the applicable statutes and regulations. To discuss an alternative approach, contact the FDA office responsible for this guidance as listed on the title page.
I. Introduction
Under FDA’s BSE feed regulation (21 CFR 589.2000) most material from deer and elk is prohibited for use in feed for ruminant animals. This guidance document describes FDA’s recommendations regarding the use in all animal feed of all material from deer and elk that are positive for Chronic Wasting Disease (CWD) or are considered at high risk for CWD. The potential risks from CWD to humans or non-cervid animals such as poultry and swine are not well understood. However, because of recent recognition that CWD is spreading rapidly in white-tailed deer, and because CWD’s route of transmission is poorly understood, FDA is making recommendations regarding the use in animal feed of rendered materials from deer and elk that are CWD-positive or that are at high risk for CWD.
In general, FDA’s guidance documents do not establish legally enforceable responsibilities. Instead, guidances describe the Agency’s current thinking on a topic and should be viewed only as recommendations, unless specific regulatory or statutory requirements are cited. The use of the word should in Agency guidances means that something is suggested or recommended, but not required.
II. Background
CWD is a neurological (brain) disease of farmed and wild deer and elk that belong in the animal family cervidae (cervids). Only deer and elk are known to be susceptible to CWD by natural transmission. The disease has been found in farmed and wild mule deer, white-tailed deer, North American elk, and in farmed black-tailed deer. CWD belongs to a family of animal and human diseases called transmissible spongiform encephalopathies (TSEs). These include bovine spongiform encephalopathy (BSE or “mad cow” disease) in cattle; scrapie in sheep and goats; and classical and variant Creutzfeldt-Jakob diseases (CJD and vCJD) in humans. There is no known treatment for these diseases, and there is no vaccine to prevent them. In addition, although validated postmortem diagnostic tests are available, there are no validated diagnostic tests for CWD that can be used to test for the disease in live animals.
Contains Nonbinding Recommendations
3
III. Use in animal feed of material from CWD-positive deer and elk
Material from CWD-positive animals may not be used in any animal feed or feed ingredients. Pursuant to Sec. 402(a)(5) of the Federal Food, Drug, and Cosmetic Act, animal feed and feed ingredients containing material from a CWD-positive animal would be considered adulterated. FDA recommends that any such adulterated feed or feed ingredients be recalled or otherwise removed from the marketplace.
IV. Use in animal feed of material from deer and elk considered at high risk for CWD Deer and elk considered at high risk for CWD include: (1) animals from areas declared by State officials to be endemic for CWD and/or to be CWD eradication zones; and (2) deer and elk that at some time during the 60-month period immediately before the time of slaughter were in a captive herd that contained a CWD-positive animal.
FDA recommends that materials from deer and elk considered at high risk for CWD no longer be entered into the animal feed system. Under present circumstances, FDA is not recommending that feed made from deer and elk from a non-endemic area be recalled if a State later declares the area endemic for CWD or a CWD eradication zone. In addition, at this time, FDA is not recommending that feed made from deer and elk believed to be from a captive herd that contained no CWD-positive animals be recalled if that herd is subsequently found to contain a CWD-positive animal.
V. Use in animal feed of material from deer and elk NOT considered at high risk for CWD
FDA continues to consider materials from deer and elk NOT considered at high risk for CWD to be acceptable for use in NON-RUMINANT animal feeds in accordance with current agency regulations, 21 CFR 589.2000. Deer and elk not considered at high risk include: (1) deer and elk from areas not declared by State officials to be endemic for CWD and/or to be CWD eradication zones; and (2) deer and elk that were not at some time during the 60-month period immediately before the time of slaughter in a captive herd that contained a CWD-positive animal.
Sunday, March 20, 2016
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer and Elk in Animal Feed ***UPDATED MARCH 2016*** Singeltary Submission
http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/GuidanceforIndustry/UCM052506.pdf?source=govdelivery&utm_medium=email&utm_source=govdelivery
Singeltary comment;
https://www.reginfo.gov/public/do/DownloadDocument?objectID=70082300
2003D-0186 Guidance for Industry: Use of Material From Deer and Elk In Animal Feed
EMC 1 Terry S. Singeltary Sr.
Vol #: 1
http://www.fda.gov/ohrms/dockets/dailys/03/Jun03/060903/060903.htm
http://www.fda.gov/ohrms/dockets/dailys/01/Oct01/101501/101501.htm
NOW, BE AWARE, OIE AND USDA HAVE NOW MADE ATYPICAL SCRAPIE AND ATYPICAL BSE A LEGAL TRADING COMMODITY, WITH NO REPORTING OF SAID ATYPICAL CASES, EXCEPT FOR A VOLUNTARY NOTE ON ANNUAL REPORT...i don't make this stuff up...terry
cwd, scrapie, transmits to pigs by oral routes, oh my!
***> However, at 51 months of incubation or greater, 5 animals were positive by one or more diagnostic methods. Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie. <***
>*** Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health. <***
***> Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 month group was positive by EIA. PrPSc was detected by QuIC in at least one of the lymphoid tissues examined in 5/6 pigs in the intracranial <6 months group, 6/7 intracranial >6 months group, 5/6 pigs in the oral <6 months group, and 4/6 oral >6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%).
***> Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
CONFIDENTIAL
EXPERIMENTAL PORCINE SPONGIFORM ENCEPHALOPATHY
LINE TO TAKE
3. If questions on pharmaceuticals are raised at the Press conference, the suggested line to take is as follows:-
"There are no medicinal products licensed for use on the market which make use of UK-derived porcine tissues with which any hypothetical “high risk" ‘might be associated. The results of the recent experimental work at the CSM will be carefully examined by the CSM‘s Working Group on spongiform encephalopathy at its next meeting.
DO Hagger RM 1533 MT Ext 3201
While this clearly is a cause for concern we should not jump to the conclusion that this means that pigs will necessarily be infected by bone and meat meal fed by the oral route as is the case with cattle. ...
we cannot rule out the possibility that unrecognised subclinical spongiform encephalopathy could be present in British pigs though there is no evidence for this: only with parenteral/implantable pharmaceuticals/devices is the theoretical risk to humans of sufficient concern to consider any action.
May I, at the outset, reiterate that we should avoid dissemination of papers relating to this experimental finding to prevent premature release of the information. ...
3. It is particularly important that this information is not passed outside the Department, until Ministers have decided how they wish it to be handled. ...
But it would be easier for us if pharmaceuticals/devices are not directly mentioned at all. ...
Our records show that while some use is made of porcine materials in medicinal products, the only products which would appear to be in a hypothetically ''higher risk'' area are the adrenocorticotrophic hormone for which the source material comes from outside the United Kingdom, namely America China Sweden France and Germany. The products are manufactured by Ferring and Armour. A further product, ''Zenoderm Corium implant'' manufactured by Ethicon, makes use of porcine skin - which is not considered to be a ''high risk'' tissue, but one of its uses is described in the data sheet as ''in dural replacement''. This product is sourced from the United Kingdom.....
Transmission of scrapie prions to primate after an extended silent incubation period
*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS.
*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated.
*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains.
***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice.
***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***
Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations
*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period,
***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014),
***is the third potentially zoonotic PD (with BSE and L-type BSE),
***thus questioning the origin of human sporadic cases.
==============
PRION 2015 CONFERENCE
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 1933-690X
WS-01: Prion diseases in animals and zoonotic potential
Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
Tuesday, December 16, 2014
Evidence for zoonotic potential of ovine scrapie prions
Hervé Cassard,1, n1 Juan-Maria Torres,2, n1 Caroline Lacroux,1, Jean-Yves Douet,1, Sylvie L. Benestad,3, Frédéric Lantier,4, Séverine Lugan,1, Isabelle Lantier,4, Pierrette Costes,1, Naima Aron,1, Fabienne Reine,5, Laetitia Herzog,5, Juan-Carlos Espinosa,2, Vincent Beringue5, & Olivier Andréoletti1, Affiliations Contributions Corresponding author Journal name: Nature Communications
Volume: 5, Article number: 5821 DOI: doi:10.1038/ncomms6821 Received 07 August 2014 Accepted 10 November 2014 Published 16 December 2014
Abstract
Although Bovine Spongiform Encephalopathy (BSE) is the cause of variant Creutzfeldt Jakob disease (vCJD) in humans, the zoonotic potential of scrapie prions remains unknown. Mice genetically engineered to overexpress the human prion protein (tgHu) have emerged as highly relevant models for gauging the capacity of prions to transmit to humans. These models can propagate human prions without any apparent transmission barrier and have been used used to confirm the zoonotic ability of BSE. Here we show that a panel of sheep scrapie prions transmit to several tgHu mice models with an efficiency comparable to that of cattle BSE.
***The serial transmission of different scrapie isolates in these mice led to the propagation of prions that are phenotypically identical to those causing sporadic CJD (sCJD) in humans.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
Subject terms: Biological sciences• Medical research At a glance
why do we not want to do TSE transmission studies on chimpanzees $ 5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.
snip... R. BRADLEY
1: J Infect Dis 1980 Aug;142(2):205-8
Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to nonhuman primates
Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.
Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were exposed to the infectious agents only by their nonforced consumption of known infectious tissues. The asymptomatic incubation period in the one monkey exposed to the virus of kuru was 36 months; that in the two monkeys exposed to the virus of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively. Careful physical examination of the buccal cavities of all of the monkeys failed to reveal signs or oral lesions. One additional monkey similarly exposed to kuru has remained asymptomatic during the 39 months that it has been under observation.
snip...
The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie by natural feeding to squirrel monkeys that we have reported provides further grounds for concern that scrapie-infected meat may occasionally give rise in humans to Creutzfeldt-Jakob disease. PMID: 6997404
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract
Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates. One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasised by the finding that some strains of scrapie produce lesions identical to the once which characterise the human dementias" Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the scrapie problem urgent if the sheep industry is not to suffer grievously. snip... 76/10.12/4.6
Nature. 1972 Mar 10;236(5341):73-4.
Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis)
Gibbs CJ Jr, Gajdusek DC. Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0
Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)
C. J. GIBBS jun. & D. C. GAJDUSEK National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland
SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey (Macaca fascicularis) with an incubation period of more than 5 yr from the time of intracerebral inoculation of scrapie-infected mouse brain. The animal developed a chronic central nervous system degeneration, with ataxia, tremor and myoclonus with associated severe scrapie-like pathology of intensive astroglial hypertrophy and proliferation, neuronal vacuolation and status spongiosus of grey matter. The strain of scrapie virus used was the eighth passage in Swiss mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton, Berkshire).
Detection of classical BSE prions in asymptomatic cows after inoculation with atypical/Nor98 scrapie
* Marina Betancor, Belén Marín, Alicia Otero, Carlos Hedman, Antonio Romero, Tomás Barrio, Eloisa Sevilla, Jean-Yves Douet, Alvina Huor, Juan José Badiola, Olivier Andréoletti & Rosa Bolea * Veterinary Research volume 54, Article number: 89 (2023)
Abstract
The emergence of bovine spongiform encephalopathy (BSE) prions from atypical scrapie has been recently observed upon experimental transmission to rodent and swine models. This study aimed to assess whether the inoculation of atypical scrapie could induce BSE-like disease in cattle. Four calves were intracerebrally challenged with atypical scrapie. Animals were euthanized without clinical signs of prion disease and tested negative for PrPSc accumulation by immunohistochemistry and western blotting. However, an emergence of BSE-like prion seeding activity was detected during in vitro propagation of brain samples from the inoculated animals. These findings suggest that atypical scrapie may represent a potential source of BSE infection in cattle.
Snip…
Further in vivo experiments challenging different mouse lines have been started in order to confirm the infectivity of the PMCA products obtained in this study. However, in conclusion, our findings show that the propagation of atypical scrapie in cattle leads to the emergence of BSE-like seeding activity. This is a concerning issue with far-reaching implications for public health and food safety. The possibility of interspecies transmission of prion diseases and the emergence of new prion strains highlight the critical need for continued surveillance and monitoring of these diseases in both animal and human populations. Early detection of prion diseases is crucial, and highly sensitive detection techniques such as PMCA can play an important role in this regard.
Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research
Title: Disease phenotype of classical sheep scrapie is changed upon experimental passage through white-tailed deer
Author item Kokemuller, Robyn item MOORE, S.JO - Oak Ridge Institute For Science And Education (ORISE) item Bian, Jifeng item WEST GREENLEE, HEATHER - Iowa State University item Greenlee, Justin
Submitted to: PLoS Pathogens Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/9/2023 Publication Date: 12/4/2023 Citation: Kokemuller, R., Moore, S., Bian, J., West Greenlee, H.M., Greenlee, J.J. 2023. Disease phenotype of classical sheep scrapie is changed upon experimental passage through white-tailed deer. PLoS Pathogens. https://doi.org/10.1371/journal.ppat.1011815. DOI: https://doi.org/10.1371/journal.ppat.1011815
Interpretive Summary: Transmissible spongiform encephalopathies (TSEs) are a group of fatal diseases caused by the accumulation of misfolded prion protein in the brain. Ruminant species such as sheep, deer, and elk can get prion diseases. In sheep the disease is called scrapie. In deer and elk, the disease is called chronic wasting disease (CWD). The source of CWD is unknown, but one possibility is that scrapie jumped from sheep to deer. When we experimentally exposed white-tailed deer to the sheep scrapie agent, all deer developed scrapie. The purpose of the current experiment was to determine if sheep can get scrapie derived from white-tailed deer. Some sheep developed scrapie after oronasal exposure to the scrapie agent from white-tailed deer. Passage through white-tailed deer results in a scrapie isolate with different strain properties than the original inoculum. The detection of new strain properties was an unexpected result that will be the subject of further studies. These results indicate that sheep could be susceptible to the scrapie agent after passage through deer if exposed to the agent in natural or agricultural settings, which could be a confounding factor to the scrapie eradication program. National and state regulatory and wildlife officials should consider this information when developing plans to reduce or eliminate TSEs.
Technical Abstract: Transmissible spongiform encephalopathy (TSE) agents have strain variations that influence disease phenotype and may affect the potential for interspecies transmission. Since deer and sheep may use the same grazing land, it is important to understand the potential transmission of TSEs between these species. The US scrapie isolate (No.13-7) had a 100% attack rate in white-tailed deer after oronasal challenge. The purpose of this study was to determine if sheep are susceptible to oronasal challenge with the scrapie agent from white-tailed deer. Suffolk lambs of various prion protein genotypes were challenged by the oronasal route with a 10% brain homogenate from scrapie-affected white-tailed deer. Sheep were euthanized and necropsied upon development of clinical signs or at the end of the experiment (72 months post-inoculation). Tissues were tested for PrPSc by enzyme immunoassay, western blot, and immunohistochemistry. The first sheep (2/2) to develop clinical signs at approximately 29 months post-inoculation (MPI) had the VRQ/VRQ genotype. One of the two sheep with the ARQ/ARQ genotype also developed clinical signs at 48 MPI. This is in contrast to the original No.13-7 inoculum that has a faster incubation period in sheep with the ARQ/ARQ genotype compared to sheep of the VRQ/VRQ genotype. The shorter incubation period in VRQ/VRQ sheep than ARQ/ARQ sheep after passage through deer indicates a phenotype change. This is important because scrapie infected deer could transmit disease to sheep resulting in new scrapie strain properties. This work raises the concern that scrapie infected deer could serve as a confounding factor to scrapie eradication programs as the scrapie agent from deer is transmissible to sheep by the oronasal route.
Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research
Title: The chronic wasting disease agent from white-tailed deer is highly infectious to humanized mice after passage through raccoons
Author item Cassmann, Eric item QI, XU - Case Western Reserve University (CWRU) item KONG, QINGZHONG - Case Western Reserve University (CWRU) item Greenlee, Justin
Submitted to: Meeting Abstract Publication Type: Abstract Only Publication Acceptance Date: 3/15/2023 Publication Date: 5/30/2023 Citation: Cassmann, E.D., Qi, X., Kong, Q., Greenlee, J.J. 2023. The chronic wasting disease agent from white-tailed deer is highly infectious to humanized mice after passage through raccoons (abstract). Meeting Abstract. 4th International Chronic Wasting Disease Symposium, May 30-June 3, 2023, Denver, Colorado. Interpretive Summary:
Technical Abstract: The aim of this study was to evaluate the zoonotic potential of the raccoon passaged chronic wasting disease (CWD) agent in humanized transgenic mice in comparison with the North American CWD agent from the original white-tailed deer (WTD) host. Pooled brain (GG96) from CWD positive deer was used to intracranially inoculate two WTD and one raccoon. Brain homogenates (10% w/v) from the raccoon and the WTD were used to intracranially inoculate transgenic mice (Tg40h) expressing the methionine 109 human prion protein. Brains and spleens were collected from mice at experimental endpoints of clinical disease or approximately 700 days post-inoculation. Tissues were divided and homogenized or fixed in 10% buffered neutral formalin. Immunohistochemistry, enzyme immunoassay, and western blot were used to detect misfolded prion protein (PrPSc) in tissue. Tg40h mice inoculated with the raccoon passaged CWD agent from WTD exhibited a 100% (12/12) attack rate with an average incubation period of 605 days. PrPSc was detected in brain tissue by enzyme immunoassay with an average optical density of 3.6/4.0 for positive brains. PrPSc also was detected in brain tissue by western blot and immunohistochemistry. No PrPSc was detected in the spleens of mice inoculated with the raccoon passaged CWD agent. Humanized mice inoculated with the CWD agent from WTD did not have detectable PrPSc using conventional immunoassay techniques. These results demonstrated that the host range of the CWD agent from WTD was expanded in our experimental model after one passage through raccoons.
Subject: Transmission of BSE by blood transfusion in sheep...
Date: Thu, 14 Sep 2000 18:19:06 -0700
From: "Terry S. Singeltary Sr."
Reply-To: Bovine Spongiform Encephalopathy
To: BSE-L@uni-karlsruhe.de
######### Bovine Spongiform Encephalopathy #########
Greetings List Members,
More Dredful news, but predictable...
kind regards,
Terry S. Singeltary Sr., Bacliff, Texas USA
===========================================
It is possible to transmit BSE to a sheep by transfusion with whole blood taken from another sheep during the symptom-free phase of an experimental BSE infection'
It is well known that variant Creutzfeldt-Jakob disease (vCJD) is caused by the same strain of agent that causes bovine spongiform encephalopathy (BSE) in cattle. F Houston and colleagues report the preliminary findings of transfusing blood from 19 UK Cheviot sheep fed with 5 g BSE-affected cattle brain into Cheviot sheep from scrapie-free flock of New Zealand-derived animals. The investigators found BSE clinical signs and pathology in one recipient of blood taken from a BSE infected animal. Immunocytochemistry on tissues taken from the transfused sheep showed widespread PrPSC deposition throughout the brain and the periphery. This finding suggests that blood donated by symptom-free vCJD-infected human beings could transmit infection to recipients of blood transfusions. In a Commentary, Paul Brown states that these observations are consistent with previous reports in experimentally infected rodents.
==================
Research letters
Volume 356, Number 9234 16 September 2000
Transmission of BSE by blood transfusion in sheep
Lancet 2000; 356: 999 - 1000
Download PDF (1 Mb)
F Houston, J D Foster, Angela Chong, N Hunter, C J Bostock
See Commentary
We have shown that it is possible to transmit bovine spongiform encephalopathy (BSE) to a sheep by transfusion with whole blood taken from another sheep during the symptom-free phase of an experimental BSE infection. BSE and variant Creutzfeldt-Jakob disease (vCJD) in human beings are caused by the same infectious agent, and the sheep-BSE experimental model has a similar pathogenesis to that of human vCJD. Although UK blood transfusions are leucodepleted--a possible protective measure against any risk from blood transmission--this report suggests that blood donated by symptom-free vCJD-infected human beings may represent a risk of spread of vCJD infection among the human population of the UK.
The demonstration that the new variant of Creutzfeldt-Jakob disease (vCJD) is caused by the same agent that causes bovine spongiform encephalopathy (BSE) in cattle1 has raised concerns that blood from human beings in the symptom-free stages of vCJD could transmit infection to recipients of blood transfusions. There is no evidence that iatrogenic CJD has ever occurred as a result of the use of blood or blood products, but vCJD has a different pathogenesis and could present different risks. CJD is one of the transmissible spongiform encephalopathies (TSEs) characterised by the deposition of an abnormal form of a host protein, PrPSc; the normal isoform (PrPC) is expressed in many body tissues. Available evidence, based on detection of infectivity in blood in rodent models, and absence of infectivity in naturally occurring TSEs, adds to the uncertainty in risk assessments of the safety of human blood. PrPSc has been reported in blood taken from preclinical TSE-infected sheep,2 but it does not follow that blood is infectious. Bioassays of human blood can only be carried out in non-human species, limiting the sensitivity of the test. One way of avoiding such a species barrier is to transfer blood by transfusion in an appropriate animal TSE model. BSE-infected sheep harbour infection in peripheral tissues3 and are thus similar to humans infected with vCJD.4 BSE infectivity in cattle does not have widespread tissue distribution.
We report preliminary data from a study involving blood taken from UK Cheviot sheep challenged orally with 5 g BSE-affected cattle brain and transfused into Cheviot sheep from a scrapie-free flock of New Zealand-derived animals (MAFF/SF flock). MAFF/SF sheep do not develop spontaneous TSE and the transfused animals are housed separately from other sheep. All sheep in the study have the PrP genotype AA136QQ171 which has the shortest incubation period of experimental BSE in sheep.5 19 transfusions from BSE-challenged sheep have been done, mostly with whole blood. Sheep have complex blood groups and only simple cross-matching can be done by mixing recipient serum and donor erythrocytes and vice versa. Therefore single transfusions only were made between sedated cross-matched animals to minimise the risk of severe reactions. Negative controls were MAFF/SF sheep transfused with blood from uninfected UK Cheviot sheep. As a positive control, MAFF/SF sheep were intravenously injected with homogenised BSE-affected cattle brain.
We have seen BSE clinical signs and pathological changes in one recipient of blood from a BSE-infected animal, and we regard this finding as sufficiently important to report now rather than after the study is completed, several years hence. The blood donation resulting in transmission of BSE to the recipient was 400 mL of whole blood taken from a healthy sheep 318 days after oral challenge with BSE. BSE subsequently developed in this donor animal 629 days after challenge, indicating that blood was taken roughly half way through the incubation period. 610 days after transfusion, the transfused sheep (D505) itself developed typical TSE signs: weight loss, moderate pruritus, trembling and licking of the lips, hind-limb ataxia, and proprioceptive abnormalities. This is the first experimental transmission of BSE from sheep to sheep and so we have nothing with which to compare this incubation period directly. In cross-species transmissions, bovine BSE injected intracerebrally gives incubation periods of about 450 days in these sheep,5 and the donor animal had an oral BSE incubation period of 629 days (see above). There are no similar data available on other infection routes. Immunocytochemistry with the antibody BG4 on tissues taken from sheep D505 showed widespread PrPSc deposition throughout the brain and periphery. Western blot analysis of brain tissue with the antibody 6H4 showed that the PrPSc protein had a glycoform pattern similar to that of experimental BSE in sheep and unlike that of UK natural scrapie (figure), indicating that the TSE signs resulted from transmission of the BSE agent. All other recipients of transfusions and positive and negative controls are alive and healthy. The positive controls, which involve a species barrier, are expected to have lengthy incubation periods. With one exception, all transfused animals are at earlier stages post-transfusion than was D505. The exception is a sheep which is healthy 635 days after transfusion with BSE-blood donated at less than 30% of the BSE incubation period of the donor sheep.
PrPSc (proteinase K treated) analysed by SDS-PAGE, immunoblotted with 6H4, and visualised with a chemiluminescent substrate
All lanes are from the same gel with different exposure times. Size markers are to the left of lane 1. Lane1: natural scrapie sheep brain, 3 min exposure. Lane 2: as lane 1, 10 min exposure. Lane 3: sheep D505, blood-transfusion recipient, 10 min exposure. Lane 4: experimental BSE-affected sheep brain, 30 s exposure. Lane 5: as lane 4, 10 min exposure. Each lane loaded with amount of protein extracted from 0·1 g wet weight of brain, except lane 3 which was extracted from 0·2 g brain.
Although this result was in only one animal, it indicates that BSE can be transmitted between individuals of the same species by whole-blood transfusion. We have no data on blood fractions or on levels of infectivity in blood of preclinical vCJD cases, but whole blood is not now used in UK transfusions. The presence of BSE infectivity in sheep blood at an early stage in the incubation period suggests that it should be possible to identify which cells are infected, to test the effectiveness of leucodepletion, and to develop a diagnostic test based on a blood sample.
We thank Karen Brown, Moira Bruce, Calum McKenzie, David Parnham, Diane Ritchie, and the Scottish Blood Transfusion Service. The project is funded by the Department of Health.
1 Bruce ME, Will RG, Ironside JW, et al. Transmissions to mice indicate that 'new variant' CJD is caused by the BSE agent. Nature 1997; 389: 488-501 [PubMed].
2 Schmerr MJ, Jenny A, Cutlip RC. Use of capillary sodium dodecyl sulfate gel electrophoresis to detect the prion protein extracted from scrapie-infected sheep. J Chromatogr B Biomed Appl 1997; 697: 223-29 [PubMed].
3 Foster JD, Bruce M, McConnell I, Chree A, Fraser H. Detection of BSE infectivity in brain and spleen of experimentally infected sheep. Vet Rec 1996; 138: 546-48 [PubMed].
4 Hill AF, Zeidler M, Ironside J, Collinge J. Diagnosis of new variant Creutzfeldt-Jakob disease by tonsil biopsy. Lancet 1997; 349: 99-100.
5 Goldmann W, Hunter N, Smith G, Foster J, Hope J. PrP genotype and agent effects in scrapie: change in allelic interaction with different isolates of agent in sheep, a natural host of scrapie. J Gen Virol 1994; 75: 989-95 [PubMed].
Institute for Animal Health, Compton, Newbury, UK (F Houston PhD, CJ Bostock PhD); and Institute for Animal Health, Neuropathogenesis Unit, Edinburgh, EH9 3JF, UK (N Hunter PhD, JD Foster BSc, Angela Chong BSc)
Correspondence to: Dr N Hunter
=======================
Commentary
Volume 356, Number 9234 16 September 2000
BSE and transmission through blood
Lancet 2000; 356: 955 - 956
Download PDF (55 Kb)
Whether the outbreak of variant Creutzfeldt-Jakob disease (vCJD) in the UK will ultimately affect hundreds, or tens of thousands of people, cannot yet be predicted.1 If large numbers of apparently healthy people are now silently incubating infections with bovine spongiform encephalopathy (BSE), the implications for public health include the possibility that blood from such individuals may be infectious. Established facts about infectivity in the blood of human beings and animals with transmissible spongiform encephalopathies (TSEs) are as follows:2-4
Blood, especially the buffy-coat component, from animals experimentally infected with scrapie or CJD and from either a clinical or preclinical incubation phase, is consistently infectious when bioassayed by intracerebral or intraperitoneal inoculation into the same species;
In naturally infected animals (sheep and goats with scrapie, mink with transmissible mink encephalopathy, and cows with BSE), all attempts to transmit disease through the inoculation of blood have failed;
Blood from four of 37 human beings with clinically evident sporadic CJD has been reported to transmit the disease after intracerebral inoculation into guineapigs, mice, or hamsters. But each success has been questioned on technical grounds and has not been reproducible; and
Epidemiological data have not revealed a single case of CJD that could be attributed to the administration of blood or blood products among patients with CJD, or among patients with hemophilia and other congenital clotting or immune deficiencies who receive repeated doses of plasma concentrates.
No comparable information about vCJD is available. However, since lymphoreticular organs, such as tonsils have been shown to contain the prion protein (which is an excellent index of infectivity), whereas it is not detectable in patients with sporadic CJD, there is some reason to worry that blood from individuals incubating vCJD might be infectious.5 Data from studies into the ability of blood from experimentally infected rodents and primates with vCJD to transmit the disease will not be available for months or years.
In this issue of The Lancet, F Houston and co-workers report convincing evidence that blood from a seemingly healthy sheep incubating BSE (infected by the oral route with brain from a diseased cow) was able to cause the disease when transfused into another sheep. This observation is entirely consistent with past experience in experimentally infected rodents. It extends current knowledge about blood infectivity in experimental models to a host/TSE strain pair that is closer to the human vCJD situation than the earlier rodent studies. It is also the first successful transfusion of BSE from blood taken during the all-important incubation period of infection. This result is part of a larger study (n=19) that includes both positive and negative control animals, all still healthy and in various early stages of the incubation period.
Is it appropriate to publish an experimental result from a single animal in a study that is not far enough along even to have validated its positive controls? Especially a result that does not in any fundamental way change our current thinking about BSE and vCJD and which would not seem to have any practical consequences for public health? The UK National Blood Transfusion Service has already implemented leucodepletion of donated blood, and imports all plasma and plasma derivatives from BSE-free countries. No further measures would seem possible--short of a draconian decision to shut down the whole UK blood-donor system. What, therefore, is the rationale for this publishing urgency? The answer, evidently, is a perceived need to "defuse", by an immediate and accurate scientific report, public reaction to possibly inaccurate media accounts. The full study, when it appears, will be an important addition to our knowledge of TSEs, but science should not be driven to what in certain medical quarters might be termed a premature emission through fear of media misrepresentation.
Paul Brown
Laboratory of Central Nervous System Studies, National Institutes of Health, Bethesda, MD 20892, USA
1 Ghani AC, Ferguson NM, Donnelly CA, Anderson RM. Predicted vCJD mortality in Great Britain. Nature 2000; 406: 583-84 [PubMed].
2 Brown P. Can Creutzfeldt-Jakob disease be transmitted by transfusion? Curr Opin Hematol 1995; 2: 472-77 [PubMed].
3 Brown P, Cervenáková L, McShane LM, Barber P, Rubenstein R, Drohan WN. Further studies of blood infectivity in an experimental model of transmissible spongiform encephalopathy, with an explanation of why blood components do not transmit Creutzfeldt-Jakob disease in humans. Transfusion 1999; 39: 1169-78 [PubMed].
4 Rohwer RG. Titer, distribution, and transmissibility of blood-borne TSE infectivity. Presented at Cambridge Healthtech Institute 6th Annual Meeting "Blood Product Safety: TSE, Perception versus Reality", MacLean, VA, USA, Feb 13-15, 2000.
5 Hill AF, Butterworth RJ, Joiner S, et al. Investigation of variant Creutzfeldt-Jakob disease and other human prion diseases with tonsil biopsy samples. Lancet 1999; 353: 183-89.
http://www.thelancet.com/
===================
TSS
From: Terry S. Singeltary Sr. (216-119-130-97.ipset10.wt.net)
Subject: Other Transmission Studies of CJD from Blood and Urine Into Mice...
Date: September 18, 2000 at 2:01 pm PST
In Reply to: Transmission of BSE by blood transfusion in sheep... posted by Terry S. Singeltary Sr. on September 15, 2000 at 9:29 am:
Transmission of Creutzfeldt-Jakob Disease from Blood and Urine Into Mice
The Lancet, November 9, 1985
Sir,--Professor Manuelidis and his colleagues (Oct 19, p896) report transmission to animals of Creutzfeldt-Jakob disease (CJD) from the buffy coat from two patients. We also transmitted the disease from whole blood samples of a patient (and of mice) infected with CJD.1 Brain, Cornea, and urine from this patient were also infectious, and the clinicopathological findings2 are summarised as follows.
A 70-year-old man was noted to have a slowing of speech and writing and some disorientation, all of which progressed rapidly. Decorticate rigidity, forced grasping, positive snout reflex, and myoclonus appeared within 2 months. Electroencephalogram revealed typical periodic synchronous discharge, and he died of pneumonia and upper gastrointestinal haemorrhage, about 3 months after onset of the symptoms. The Brain weighed 1290g and showed severe histological changes diagnostic of CJD, including spongiform change, loss of nerve cells, and diffuse proliferation of astrocytes. There were no inflammatory cells, microglia, neurofibrillary tangles, and amyloid plaques, although virus-like particles were detected by electron microscopy.
Results of innoculation in Mice
Inocula NO* Incubation period (days)+ Brain 7/10 (4) 789 (+ or - 112) Cornea 1/6 (0) 1037 Blood 2/13 (0) 1080 (+ or - 69) Urine 5/10 (1) 880 (+ or - 55) CSF 0/10
* Number of mice with CJD change/number examined histologically. Number with amyloid plaques shown in parentheses.
+ means + or - SD
Samples were taken aseptically at necropsy. 10% crude homogenates of brain and cornea in saline, whole blood (after crushing a clot), and untreated CSF and urine were innoculated intracerebrally into CF1 strain mice (20 ul per animal). Some mice showed emaciation, bradykinesia, rigidity of the body and tail, and sometimes tremor after long incubation periods. Tissues obtained after the animal died (or was killed) were studied histologically (table). Animals infected by various inocula showed common pathological changes, consisting of severe spongiform changes, glial proliferation, and a moderate loss of nerve cells. A few mice inoculated with brain tissue or urine had the same amyloid plaques found in patients and animals with CJD.3
In our long-term experiments, inoculating materials taken from twenty patients with CJD or Gerstmann-Straussler-Scheinker's disease (GSS) into rodents, positive results were obtained in seventeen cases, including this patient. Brain tissue transmitted the disease most frequently within the shortes incubation period, except for one case where the lymph node was the most infectious. Transmission through the cornea has been noted in man4 and in guineapigs.5 Whole blood samples taken from three patients were inoculated and a positive transmission occured only in the case recorded here. Mouse-to-mouse transmission through blood inoculation was successful after a mean incubation period of 365 days.1 Transmission through urine was positive in this patient only, and negative in one other patient and in many infected animals. Transmission through the CSF from eight patients was negative, yet transmission via the CSF of infected rats was positive.1
As viraemia has been proved in guineapigs,6 mice,1,7 and lately in patients with CJD, blood for transfusion or blood products for medical use must be tested for unconventional pathogens. For this purpose, we inoculated blood products inot rodents.8 The CJD pathogen was not found in the products examined. However, this approach takes too long to be of practical value. More efficient methods must be developed to detect pathogens and to eliminate them from blood. One proposal9 is to apply membrane filtration to the pruification protocol of human growth hormone suspected of being contaminated with CJD. Similar methods are needed for blood contamination.
Department of Neuropathology, Neurological Institute, Faculty of Medicine, Kyushu University, Fukuoka812, Japan
JUN TATEISHI
1. Tateishi J, Sato Y, Kaga M. Doi H, Ohta M. Experimental transmission of human subacute spongiform encephalopathy to small rodents 1: Clinical and histological observations. Acta Neuropathol (Berl) 1980; 51: 127.
2. Shibayama Y, Sakaguchi Y, Nakata K, et al, Creutzfeldt-Jakob disease with demonstration of virus-like particles. Acta pathol Jpn 1982;32: 695.
3. Tateishi J, Nagara H, Hikita K, Sato Y. Amyloid plaques in the brains of mice with Creutzfeldt-Jakob disease. Ann Neurol 1984; 15: 278.
4. Duffy P, Wolf J, Colings G, DeVoe AG, Streeten B, Cowen D. Possible person-to-person transmission of Creutzfeldt-Jakob disease. N Engl J Med 1974; 290: 692.
5. Manuelidis EE, Angelo JN, Gorgacz EJ, Kim JH, Manuelidis L. Experimental Creutzfeldt-Jakob disease transmitted via the eye with infected cornea. N Engl J Med 1977; 296: 1334.
6. Manuelidis EE, Gorgacz EJ, Manuelidis L. Viremia in experimental Creutzfeldt-Jakob disease. Science 1978: 200: 1069.
7. Kuroda Y, Gibbs CJ Jr, Amyx HL, Gajdusek DC. Creutzfeldt-Jakob disease in mice. Persistent viremiam and preferential replication of virus in low-density lymphocytes. Infect Immun 1983; 41: 154.
8. Tateishi J, Tsuji S. Unconventional pathogens causing spongiform encephalopathis absent in blood products. J Med Virol 1985; 15: 11.
9. Tateishi J, Kitamoto T, Hiratani H. Creutzfeldt-Jakob disease pathogen in growth hormone preparations is eliminatable. Lancet (in press).
========================================================
also, this from the Her Majesty's Government...TSS
Subject: Transmission of TSEs through blood
Date: Tue, 28 Mar 2000 14:48:35 +0100
From: Ralph Lucas
Reply-To: Bovine Spongiform Encephalopathy
To: BSE-L@uni-karlsruhe.de
######### Bovine Spongiform Encephalopathy #########
The Lord Lucas asked Her Majesty's Government:
Whether there is any evidence that any Transmissible Spongiform Encephalopathy in any species can be transmitted through blood; and whether they will place in the Library of the House copies of the principal relevant scientific papers. (HL1545)
The Parliamentary Under-Secretary of State, Department of Health (Lord Hunt of Kings Heath):
Some animal studies have shown that certain transmissible spongiform encephalopathies can be experimentally transmitted from animal to animal through blood components. However, the Spongiform Encephalopathy Advisory Committee at its February meeting reviewed recent research undertaken in this area and did not consider any measures were necessary, in addition to those already in place, to reduce any potential risk to public health from human blood and blood products.
Copies of the following relevant scientific papers are being placed in the Library.
Brown P, 1995, "Can Creutzfeldt-Jakob Disease be transmitted by Transfusion?" Haematology 2: 472 - 477.
Brown et al 1999, Further studies of blood infectivity in an experimental model of transmissible spongiform encephalopathy, with an explanation of why blood components do not transmit Creutzfeldt - Jakob disease in humans.
Transfusion Vol. 39, November/December 1169 - 1178.
Preclinical transmission of prions by blood transfusion is influenced by donor genotype and route of infection
M. Khalid F. Salamat ,A. Richard Alejo Blanco ,Sandra McCutcheon ,Kyle B. C. Tan,Paula Stewart,Helen Brown,Allister Smith,Christopher de Wolf,Martin H. Groschup,Dietmar Becher,Olivier Andréoletti,Marc Turner,Jean C. Manson,E. Fiona Houston
Published: February 18, 2021https://doi.org/10.1371/journal.ppat.1009276
Abstract
Variant Creutzfeldt-Jakob disease (vCJD) is a human prion disease resulting from zoonotic transmission of bovine spongiform encephalopathy (BSE). Documented cases of vCJD transmission by blood transfusion necessitate on-going risk reduction measures to protect blood supplies, such as leucodepletion (removal of white blood cells, WBCs). This study set out to determine the risks of prion transmission by transfusion of labile blood components (red blood cells, platelets, plasma) commonly used in human medicine, and the effectiveness of leucodepletion in preventing infection, using BSE-infected sheep as a model. All components were capable of transmitting prion disease when donors were in the preclinical phase of infection, with the highest rates of infection in recipients of whole blood and buffy coat, and the lowest in recipients of plasma. Leucodepletion of components (<106 WBCs/unit) resulted in significantly lower transmission rates, but did not completely prevent transmission by any component. Donor PRNP genotype at codon 141, which is associated with variation in incubation period, also had a significant effect on transfusion transmission rates. A sensitive protein misfolding cyclic amplification (PMCA) assay, applied to longitudinal series of blood samples, identified infected sheep from 4 months post infection. However, in donor sheep (orally infected), the onset of detection of PrPSc in blood was much more variable, and generally later, compared to recipients (intravenous infection). This shows that the route and method of infection may profoundly affect the period during which an individual is infectious, and the test sensitivity required for reliable preclinical diagnosis, both of which have important implications for disease control. Our results emphasize that blood transfusion can be a highly efficient route of transmission for prion diseases. Given current uncertainties over the prevalence of asymptomatic vCJD carriers, this argues for the maintenance and improvement of current measures to reduce the risk of transmission by blood products.
Author summary
Variant Creutzfeldt-Jakob disease (vCJD) resulted from zoonotic transmission of bovine spongiform encephalopathy (BSE), and has also been transmitted by blood transfusion. One of the most important risk reduction measures introduced by human transfusion services to safeguard the blood supply is leucodepletion (removal of white blood cells) of blood components. This study represents the largest experimental analysis to date of the risks of prion infection associated with transfusion of labile blood components, and the effectiveness of leucodepletion in preventing transmission. Using a BSE-infected sheep model, we found that red blood cells, platelets and plasma from preclinical donors were all infectious, even after leucodepletion, although leucodepletion significantly reduced transmission rates. In addition, the time course of detection of prions in blood varied significantly depending on the route and method of infection. This has important implications for the risk of onward transmission, and suggests that further improvements in sensitivity of diagnostic tests will be required for reliable preclinical diagnosis of vCJD and other prion diseases. The results of this study support the continuation of current measures to reduce the risk of vCJD transmission by blood products, and suggest areas for further improvement.
1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8
***> Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery.
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of
Neurological Disorders and Stroke, National Institutes of Health,
Bethesda, MD 20892.
Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
PMID: 8006664 [PubMed - indexed for MEDLINE]
Prion Conference 2018 Abstracts
BSE aka MAD COW DISEASE, was first discovered in 1984, and it took until 1995 to finally admit that BSE was causing nvCJD, the rest there is history, but that science is still evolving i.e. science now shows that indeed atypical L-type BSE, atypical Nor-98 Scrapie, and typical Scrapie are all zoonosis, zoonotic for humans, there from.
HOW long are we going to wait for Chronic Wasting Disease, CWD TSE Prion of Cervid, and zoonosis, zoonotic transmission to humans there from?
Studies have shown since 1994 that humans are susceptible to CWD TSE Prion, so, what's the hold up with making CWD a zoonotic zoonosis disease, the iatrogenic transmissions there from is not waiting for someone to make a decision.
***> 2021
GUIDANCE DOCUMENT
Recommendations to Reduce the Possible Risk of Transmission of Creutzfeldt-Jakob Disease and Variant Creutzfeldt-Jakob Disease by Blood and Blood Components
Guidance for Industry
AUGUST 2020
WEDNESDAY, SEPTEMBER 02, 2020
Recommendations to Reduce the Possible Risk of Transmission of Creutzfeldt-Jakob Disease and Variant Creutzfeldt-Jakob Disease by Blood and Blood Components Guidance for Industry
I believe it is very foolish to start relaxing safety measures for blood products via Sporadic Creutzfeldt Jakob Disease sCJD TSE Prion, since sCJD is not a single strain of TSE Prion, but many different strains of CJD, now even including VPSPr. also, what about sporadic FFI and sporadic GSS?
THURSDAY, JULY 02, 2020
Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure
Friday, October 20, 2023
An investigation has been opened into the death of a scientist who was studying a transmissible and deadly disease CJD in Spain DEGENERATIVE DISEASES
An investigation has been opened into the death of a scientist who was studying a transmissible and deadly disease in Spain
Three institutions are trying to ascertain the origin of the infectious Creutzfeldt-Jakob disease samples discovered in the biochemist’s laboratory. The 45-year-old investigator died in 2022
The University of Barcelona’s School of Medicine, in L’Hospitalet de Llobregat, where laboratory 4141 is located.
MASSILIANO MINOCRI
Manuel Ansede
MANUEL ANSEDE
Madrid - OCT 19, 2023 - 16:15 EDT
A prestigious Spanish researcher of Creutzfeldt-Jakob disease died last year after experiencing symptoms consistent with this deadly ailment, as EL PAÍS has learned from multiple sources at the three institutions involved. Three months ago, the University of Barcelona opened an internal investigation to ascertain the origin of thousands of unauthorized samples, some of them infectious, discovered in a freezer in its laboratory 4141, where the deceased biochemist worked. He was a member of the Bellvitge Biomedical Research Institute (IDIBELL) and the CIBER public consortium. These two institutions have joined the internal investigation, after noting concern among colleagues at the facility, who did not know the level of risk to which they were exposed without their knowledge. This neurodegenerative disease incubates silently for years, but when symptoms appear — rapid dementia and muscle stiffness — it is fatal. Life expectancy after diagnosis is barely six months. Its best-known animal equivalent is mad cow disease.
The biochemist joined the 4141 lab at the University of Barcelona in January 2018 as a principal investigator with a group of his own; his wife joined shortly after. Together, they identified characteristic substances in human cerebrospinal fluid, useful for the diagnosis of rapid dementia. In November 2020, the now deceased scientist began to feel unwell and asked to leave. After his colleagues found out that his symptoms were consistent with Creutzfeldt-Jakob disease, he demanded absolute privacy and decided to hide his diagnosis, according to the sources consulted for this article. He died at the age of 45.
On December 18, 2020, the head of the 4141 laboratory, Isidre Ferrer, a professor of Pathology at the University of Barcelona and a member of IDIBELL, informed the directors of both institutions that suspicious samples of cerebrospinal fluid from people with Creutzfeldt-Jakob disease and other neurodegenerative types of dementia had been discovered by chance in a freezer at 80 degrees below zero, according to internal documentation to which EL PAÍS had access. The thousands of unauthorized samples from patients and animals were in a drawer reserved for the sick researcher’s group and lacked records indicating their presence. The University of Barcelona then ordered the immediate closure and decontamination of laboratory 4141, located in the School of Medicine at L’Hospitalet de Llobregat.
Doctor Gabriel Capellá, the director of IDIBELL, explains that they have identified “a maximum of eight people” who worked in the laboratory at that time, in addition to the deceased scientist and Isidre Ferrer. Some of these coworkers have required months of psychological care. The university’s safety office and IDIBELL’s prevention service determined that there was “an unacceptable risk,” although Capellá emphasizes that “there is no record of any occupational accident” in which a researcher could have been infected with contaminated material. Creutzfeldt-Jakob disease and other human transmissible spongiform encephalopathies are caused by abnormal proteins called prions, which accumulate in the brain and cause a microscopic sponge-like appearance. There are only one or two cases per million inhabitants, the vast majority of which are of unknown cause, but cases of the disease have also been reported after contact with surgical instruments contaminated by these prions.
The three institutions involved took more than two years to send the suspect samples for analysis to a specialized center, the CIC bioGUNE, in Derio, Spain. A spokeswoman for the University of Barcelona says that they sent them in December 2022 and the three organizations received the results in March 2023. Four months later, in July, the legal departments at the three institutions finally informed the 4141 laboratory workers that the Creutzfeldt-Jakob disease samples were potentially infectious, as feared. “You can debate whether we have been quick [in our response] or not, but we have been transparent. We are [part of] three institutions that had to agree, and we have acted as guarantors,” says Capellá. A similar situation also occurred in France; following the death of a researcher from Creutzfeldt-Jakob in 2019 and the discovery of another suspected case, all public laboratories investigating prion diseases decided to temporarily close in July 2021 to review their protocols.
Laboratory 4141 was not equipped to handle high biohazard samples. It did not even have a biosafety hood. At the end of 2018, the CIBER public consortium signed an agreement so that the group could work with these dangerous samples at the high-security laboratory of the Animal Health Research Center (CReSA) in Bellaterra, Spain, near Barcelona. According to the sources we consulted, there was no reason to have the contaminated material in laboratory 4141, beyond saving time during experiments, since the CReSA bunker is 30 kilometers (about 19 miles) away and required waiting one’s turn to use. Isidre Ferrer, the head of the facility at the time, who has since retired, prefers not to comment on the case until the internal investigation is completed, but he emphasizes that he was unaware of the existence of these dangerous samples.
The IDIBELL director recalls that the deceased scientist was “a promising and brilliant researcher.” From 2013 to 2017, he worked at the University Medical Center of Göttingen (Germany) under neurologist Inga Zerr, a leading international expert in Creutzfeldt-Jakob disease. Physician Margarita Blázquez, who manages the CIBER public consortium, notes that the disease’s incubation period can last several years, so, if the deceased researcher really had it, he also could have become infected with it in Germany or at another of his previous laboratories. This newspaper has tried to contact the scientist’s widow via email but has not received a response. She asked to be discharged shortly after her husband did. The three institutions are now investigating whether the couple handled the dangerous samples without authorization in lab 4141. A third person affiliated with CIBER, a member of the now-deceased biochemist’s research group, worked with potentially infectious Creutzfeldt-Jakob samples without being informed that they were infectious.
The security office of the University of Barcelona believes that the samples would only have been a problem in the case of accidental inoculation or ingestion while handling them. But internal documents confirm the alarm the situation has caused on campus. “The laboratory technicians and investigators express their enormous concern about the fact that, so far, it has not been possible to determine the origin of the doctor’s illness. They are left to worry about whether they may suffer the same fate in a few years’ time as a result of uncontrolled contamination that may have been created in the laboratory,” according to the minutes of a December 22, 2020, meeting between workers and Carles Solsona, the director of the Department of Pathology at the University of Barcelona. “This fear causes them to suffer a state of permanent anguish, causing insomnia and irritability.”
The IDIBELL director sent a message to the center’s entire staff on the 11th, five days after EL PAÍS informed him that it was investigating the case. Gabriel Capellá then told his workers of “a very serious incident that became known on campus for the first time at the end of 2020.″ With “deep dismay,” Capellá announced the researcher’s death “due to a possible prion condition,” with “a possible iatrogenic [a disease acquired by contact with contaminated materials during a medical procedure].” The director also reported finding “potentially dangerous samples” in a freezer. “Our priority is to ensure that this situation is handled rigorously and transparently to limit the damage to the reputation of our institutions,” he said.
Do you have more information about this case or other similar ones? You can write to us at mansede@elpais.es.
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Friendly fire, pass it forward, they call it iatrogenic cjd, or what i call 'tse prion poker', are you all in $$$
all iatrogenic cjd is, is sporadic cjd, before the iatrogenic event is discovered, traced back, proven, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic cjd...
Direct neural transmission of vCJD/BSE in macaque after finger incision CORRESPONDENCE
Direct neural transmission of vCJD/BSE in macaque after finger incision
Jacqueline Mikol1 · Jérôme Delmotte1 · Dolorès Jouy1 · Elodie Vaysset1 · Charmaine Bastian1 · Jean‑Philippe Deslys1 ·
Emmanuel Comoy1 Received: 10 July 2020 / Revised: 8 September 2020 / Accepted: 25 September 2020 / Published online: 6 October 2020 © The Author(s) 2020
Non-human primates appeared as the closest model to study human iatrogenic prion diseases [14]: we report here the consequences of variant Creutzfeldt–Jakob disease/bovine spongiform encephalopathy (vCJD/BSE) inoculation in a cynomolgus macaque finger, with the demonstration of an original mode of propagation and the practical risk for professional exposure.
The distal right middle finger handpad of a 4-year-old macaque was incised on both lateral sides to induce local inflammation, and then injected with the equivalent of 10 mg of a BSE, orally challenged macaque brain [18]. After an 18 months period of finger clumsiness, the clinical disease (behaviour abnormalities, fear, hyperesthesia, gait disturbances, shaking) began 7.5 years after inoculation and euthanasia took place 2 months later for welfare reasons. Motor conduction velocity of the right median nerve was reduced to one-third of the left counterpart and sensory potential was not detected.
Histological and biochemical studies were performed as previously described. All the elements of the triad were present [7–9]: spongiform change was moderate in neocortex, striatum, brain stem, mild in spinal cord but severe in thalamus and cerebellum; neuronal loss was globally moderate, but severe in cerebellum and sacral spinal cord (vacuolated neurons); gliosis was severe in thalamus, cerebellum and brain stem and moderate elsewhere (Supplementary Fig. 1). ELISA and western blot (WB) showed the expected accumulation of PrPres with BSE glycophoretic pattern at all levels of brain and spinal cord (Supplementary Fig. 2).
In the brain, PrPd deposits were laminar into the cortical deep layers, massive into thalamus, basal ganglia, cerebellum, and brain stem. In spinal cord, PrPd was symmetrically distributed, intense in the Substantia gelatinosa and nucleus dorsal of Clarke while decreased at sacral level. Deposits were diverse into the whole CNS: synaptic, perineuronal, reticular aggregates, mini-plaques, plaques, and incomplete florid plaques. The retinal plexiform layers were labelled (Supplementary Fig. 1i). There were no amyloid or tau deposits.
Unusual PrPd deposits were observed along dendrites, short and long axons, neuritic threads tracing fne networks of straight lines or like strings of pearls (Supplementary Fig. 3). They were present into deep neocortex, basal ganglia, and motoneurons. Such long processes are not frequent but have been reported in human [13] and experimental studies [10, 22]. PrPd deposits were also noted as very mild into striato-pallidal projections, both limbs of internal capsule and fornix (Supplementary Fig. 3). The presence of PrPd in white matter has been reported (Supplementary text 4).
Peripherally, the expected PrPd was undetectable in lymphoid organs, including spleen, through biochemical or immunohistochemical analyses, while prion replication was detected in the peripheral nervous system (PNS): PrPd staining was visualized in many dorsal root ganglia (DRG) but only in nerves innervating the forelimb site of injection (median and ulnar nerves). At the cellular level, PrPd was limited to ganglia and satellite cells in DRG and Schwann cells (Scs) all along nerves whereas axons were never labelled (Fig. 1). Previously, using postmortem immunohistochemical studies (listed in Supplementary text 5), PrPd has been shown in peripheral nervous system in all forms of human neuropathies, albeit more frequently in vCJD, mostly in posterior root nerve fbres at adaxonal location and/or in ganglion and satellite cells. The restricted amount of PrPd was repeatedly underlined but, recently, prion RTQuiC was positive in all nerves examined [2]. PrPd has also been described, frst in scrapie [17] then in BSE, as limited “adaxonal deposits” or/and Sc deposits, with or without DRG cell involvement (review in [4] and Supplementary text 6). Previous studies of the mode of propagation of PrPd have reported variable observations and analyses depending on strains, host species and genotype (Supplementary text 6); the authors discussed the role of the sensory route of trafficking of prions, the modifications of axonal transport, the centrifugal versus centripetal spread of PrPd .
After peripheral infection, accumulation of infectious agent is reputed to occur in lymphoid tissues before direct neuroinvasion [18, 19], even with very little apparent peripheral lymphoreticular deposition [6, 20]. Here, there is no apparent replication/amplification of vCJD/BSE agent in the lymphoid tissues of the exposed macaque. In this model, the neural contamination occurred directly in the highly innervated finger while neuroinvasion appears to occur in Scs along the median nerve to the DRG, with the appearance of the classical labelling of ganglion cells which indicates the onset of the first level of neuronal infection. This model provides direct evidence of the hypothesis of a sequential infection of Scs from the periphery to the CNS, followed by a secondary diffusion into the spinal cord, as already considered by our group [15] and others [1, 3, 11, 12, 21]. It is to note that studies based on intra-sciatic nerve injections in hamsters [16] and transgenic mice [12] had established a rate of transport of infectivity of, respectively, 0.5–2 mm and 0.7 mm per day. This key role of Scs could explain both the low speed of propagation and the discrepancy between the paucity of PrPd into the distal part of the sensory nerves followed by the positivity of DRG, satellite cells and proximal roots.
In conclusion, we have observed that the exposure of a primate to vCJD/BSE through a distal finger lesion induces, after more than 7.5 years of silent incubation, a massive deposit of PrPd , strictly restricted to the nervous system and the eye.
Our data suggest a new type of pure unique peripheral nervous contamination in which the Scs would have a major role in the mode of centripetal progression of PrPd in the peripheral nervous system. Moreover, considering the fact that, recently, “a variant CJD diagnosed 7.5 years after occupational exposure” (cryomicrotomy) in a technician was observed [5], this experimental case report supports the risk linked to professional exposure and reinforces the necessity of adequate measures of prevention.
Second death in France in a laboratory working on prions
Creutzfeldt-Jakob disease has killed a person who handled this infectious agent at Inrae in Toulouse. After a first death in 2019, a moratorium on work on this pathogen has been extended.
By Hervé Morin
Creutzfeldt-Jakob disease killed a few days ago a retired research technician from the National Research Institute for Agriculture, Food and the Environment (Inrae), who had worked in Toulouse in contact of biological tissue infected with prions. This death sows consternation and concern in the scientific community working with these infectious agents. It follows the death, on June 17, 2019, of Emilie Jaumain, a 33-year-old laboratory technician, suffering from the same incurable neurodegenerative disease. The young woman is said to have contracted it in 2010, cutting herself while handling fragments of the brains of mice infected with prions, in another unit of INRAE, in Jouy-en-Josas.
Computer representation of part of a prion protein on a light micrograph of pyramidal nerve cells (neurons, in black) in the cerebellum of the brain. ALFRED PASIEKA / SCIENCE PHOTO LIBRARY
Regarding the retiree from Toulouse, it will be necessary to determine whether she was the victim of a genetic or sporadic form of Creutzfeldt-Jakob disease, if the disease may have been caused by the ingestion of meat contaminated by the agent of encephalopathy. bovine spongiform (BSE, also called mad cow disease) or, as in the case of Emilie Jaumain, if accidental occupational exposure can be claimed. Prion diseases are caused by proteins taking an aberrant conformation, which gives them the property of replicating to form aggregates that are deleterious for neurons. There are around 150 cases per year in France, resulting in fatal degeneration of the central nervous system.
Temporary suspension of work on prions in French public research laboratories
PRESS RELEASE - The general directorates of ANSES, CEA, CNRS, INRAE and Inserm, have decided jointly and in agreement with the Ministry of Higher Education, Research and Innovation to suspend as a precaution all their research and experimentation work relating to prion diseases, for a period of three months.
This precautionary measure is motivated by the knowledge of a possible new case of a person suffering from Creutzfeldt-Jakob disease and who worked in a laboratory for research on prions.
Posted on July 27, 2021
The suspension period put in place as of this day will make it possible to study the possibility of a link between the observed case and the person's former professional activity and to adapt, if necessary, the preventive measures in force in the research laboratories.
The person with Creutzfeldt-Jakob disease (CJD)1, whose form is not yet known, is a retired INRAE agent. This could be the second case of infectious CJD affecting a scientist who worked on prions, after that of an assistant engineer who died of the disease in 2019, and who was injured in 2010 during of an experiment.
Following this death, a general inspection mission was launched in July 2019 by the ministries of research and agriculture with French laboratories handling prions. Submitted in October 2020, the report concluded on the regulatory compliance of the laboratories visited as well as the presence of a risk control culture within the research teams.
Research around prion proteins, with high public health issues, allows major advances in the understanding of the functioning of these infectious pathogens, and contributes to results that are transferable to other related degenerative diseases such as Alzheimer's and Alzheimer's diseases. Parkinson's.
At the level of each establishment, regular and transparent information will be provided to all the working communities concerned by this measure.
1 The disease Creutzfeldt-Jakob disease (CJD) is one of prion diseases - still called encephalopathies subacute spongiform transmitted(TSE) - of diseases rare, characterized by a degeneration rapid and fatal the system nervous central. They are caused by the accumulation in the brain of a normally expressed protein but poorly conformed - the prion protein - which leads to the formation of deleterious aggregates for neurons. For now , no treatment will allow to change the course of these diseases. It can be of origin sporadic , form the most frequent , original genetic or finally to form infectious following a contamination.
France issues moratorium on prion research after fatal brain disease strikes two lab workers
By Barbara CasassusJul. 28, 2021 , 4:35 AM
PARIS—Five public research institutions in France have imposed a 3-month moratorium on the study of prions—a class of misfolding, infectious proteins that cause fatal brain diseases—after a retired lab worker who handled prions in the past was diagnosed with Creutzfeldt-Jakob disease (CJD), the most common prion disease in humans. An investigation is underway to find out whether the patient, who worked at a lab run by the National Research Institute for Agriculture, Food and Environment (INRAE), contracted the disease on the job.
If so, it would be the second such case in France in the past few years. In June 2019, an INRAE lab worker named Émilie Jaumain died at age 33, 10 years after pricking her thumb during an experiment with prion-infected mice. Her family is now suing INRAE for manslaughter and endangering life; her illness had already led to tightened safety measures at French prion labs.
The aim of the moratorium, which affects nine labs, is to “study the possibility of a link with the [new patient’s] former professional activity and if necessary to adapt the preventative measures in force in research laboratories,” according to a joint press release issued by the five institutions yesterday.
“This is the right way to go in the circumstances,” says Ronald Melki, a structural biologist at a prion lab jointly operated by the French national research agency CNRS and the French Alternative Energies and Atomic Energy Commission (CEA). “It is always wise to ask questions about the whole working process when something goes wrong.” "The occurrence of these harsh diseases in two of our scientific colleagues clearly affects the whole prion community, which is a small 'familial' community of less than 1000 people worldwide," Emmanuel Comoy, deputy director of CEA's Unit of Prion Disorders and Related Infectious Agents, writes in an email to Science. Although prion research already has strict safety protocols, "it necessarily reinforces the awareness of the risk linked to these infectious agents," he says.
In Jaumain’s case, there is little doubt she was infected on the job, according to a paper published in The New England Journal of Medicine (NEJM) in 2020. She had variant CJD (vCJD), a form typically caused by eating beef contaminated with bovine spongiform encephalopathy (BSE), or mad cow disease. But Europe’s BSE outbreak ended after 2000 and vCJD virtually disappeared; the chance that someone of Jaumain’s age in France would contract food-borne vCJD is “negligible or non-existent,” according to the paper.
A scientist with inside knowledge says the new patient, a woman who worked at INRAE’s Host-Pathogen Interactions and Immunity group in Toulouse, is still alive. French authorities were apparently alerted to her diagnosis late last week. The press release suggests it’s not yet clear whether the new case is vCJD or “classic” CJD, which is not known to be caused by prions from animals. Classic CJD strikes an estimated one person per million. Some 80% of cases are sporadic, meaning they have no known cause, but others are genetic or contracted from infected human tissues during transplantations. The two types of CJD can only be distinguished through a postmortem examination of brain tissue.
Lab infections are known to occur with many pathogens, but exposure to CJD-causing prions is unusually risky because there are no vaccines or treatments and the condition is universally fatal. And whereas most infections reveal themselves within days or weeks, CJD’s average incubation period is about 10 years.
For Jaumain, who worked at INRAE’s Molecular Virology and Immunology Unit in Jouy-en-Josas, outside Paris, that long period of uncertainty began on 31 May 2010, when she stabbed her left thumb with a curved forceps while cleaning a cryostat—a machine that can cut tissues at very low temperatures—that she used to slice brain sections from transgenic mice infected with a sheep-adapted form of BSE. She pierced two layers of latex gloves and drew blood. “Émilie started worrying about the accident as soon as it had happened, and mentioned it to every doctor she saw,” says her widower, Armel Houel.
In November 2017, Jaumain developed a burning pain in her right shoulder and neck that worsened and spread to the right half of her body over the following 6 months, according to the NEJM paper. In January 2019, she became depressed and anxious, suffering memory impairment and hallucinations. “It was a descent into hell,” Houel says. She was diagnosed with “probable vCJD” in mid-March of that year and died 3 months later. A postmortem confirmed the diagnosis.
“The occurrence of these harsh diseases in two of our scientific colleagues clearly affects the whole prion community.” Emmanuel Comoy, French Alternative Energies and Atomic Energy Commission
INRAE only recently admitted the likely link between Jaumain’s illness and the accident. “We recognize, without ambiguity, the hypothesis of a correlation between Emilie Jaumain-Houel’s accident … and her infection with vCJD,” INRAE chair and CEO Philippe Mauguin wrote in a 24 June letter to an association created by friends and colleagues to publicize Jaumain’s case and lobby for improvements in lab safety. (Science has obtained a copy of the letter, which has not been made public.)
Jaumain’s family has filed both criminal charges and an administrative suit against INRAE, alleging a range of problems at Jaumain’s lab. She had not been trained in handling dangerous prions or responding to accidents and did not wear both metal mesh and surgical gloves, as she was supposed to, says Julien Bensimhon, the family’s lawyer. The thumb should have been soaked in a bleach solution immediately, which did not happen, Bensimhon adds.
Independent reports by a company specializing in occupational safety and by government inspectors have found no safety violations at the lab; one of them said there was a “strong culture” of risk management. (Bensimhon calls the reports “biased.”)
The government inspectors’ report concluded that Jaumain’s accident was not unique, however. There had been at least 17 accidents among the 100 or so scientists and technicians in France working with prions in the previous decade, five of whom stabbed or cut themselves with contaminated syringes or blades. Another technician at the same lab had a fingerprick accident with prions in 2005, but has not developed vCJD symptoms so far, Bensimhon says. “It is shocking that no precautionary measures were taken then to ensure such an accident never happened again,” he says.
In Italy, too, the last person to die of vCJD, in 2016, was a lab worker with exposure to prion-infected brain tissue, according to last year’s NEJM paper, although an investigation did not find evidence of a lab accident. That patient and the lab they worked at have not been identified.
After Jaumain’s diagnosis, “We contacted all the research prion labs in France to suggest they check their safety procedures and remind staff about the importance of respecting them,” says Stéphane Haïk, a neuroscientist at the Paris Brain Institute at Pitié-Salpêtrière Hospital who helped diagnose Jaumain and is the corresponding author on the paper. Many labs tightened procedures, according to the government inspectors' report, for instance by introducing plastic scissors and scalpels, which are disposable and less sharp, and bite and cut-resistant gloves. A team of experts from the five research agencies is due to submit proposals for a guide to good practice in prion research to the French government at the end of this year.
The scientific community has long recognized that handling prions is dangerous and an occupational risk for neuropathologists, says neuropathologist Adriano Aguzzi of the University of Zurich. Aguzzi declined to comment on the French CJD cases, but told Science his lab never handles human or bovine prions for research purposes, only for diagnostics. “We conduct research only on mouse-adapted sheep prions, which have never been shown to be infectious to humans,” Aguzzi says. In a 2011 paper, his team reported that prions can spread through aerosols, at least in mice, which “may warrant re-thinking on prion biosafety guidelines in research and diagnostic laboratories,” they wrote. Aguzzi says he was “totally shocked” by the finding and introduced safety measures to prevent aerosol spread at his own lab, but the paper drew little attention elsewhere.
The moratorium will "obviously" cause delays in research, but given the very long incubation periods in prion diseases, the impact of a 3-month hiatus will be limited, Comoy says. His research team at CEA also works on other neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease, and will shift some of its efforts to those.
Although Jaumain’s diagnosis upset many in the field, it hasn't led to an exodus among researchers in France, Haïk says: “I know of only one person who resigned because they were so worried.”
With reporting by Martin Enserink.
Posted in: EuropeHealthScientific Community
doi:10.1126/science.abl6587
Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure
Variant Creutzfeldt–Jakob disease was identified in a technician who had cut her thumb while handling brain sections of mice infected with adapted BSE 7.5 years earlier. The long incubation period was similar to that of the transfusion-transmitted form of the disease.
Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure
TO THE EDITOR:
We report a case of variant Creutzfeldt–Jakob disease (CJD) that was plausibly related to accidental occupational exposure in a technician who had handled murine samples contaminated with the agent that causes bovine spongiform encephalopathy (BSE) 7.5 years earlier.
In May 2010, when the patient was 24 years of age, she worked in a prion research laboratory, where she handled frozen sections of brain of transgenic mice that overexpressed the human prion protein with methionine at codon 129. The mice had been infected with a sheep-adapted form of BSE. During this process, she stabbed her thumb through a double pair of latex gloves with the sharp ends of a curved forceps used to handle the samples. Bleeding was noted at the puncture site.
In November 2017, she began having burning pain in the right shoulder and neck. The pain worsened and spread to the right half of her body during the following 6 months. In November 2018, an examination of a sample of cerebrospinal fluid (CSF) obtained from the patient was normal. Magnetic resonance imaging (MRI) of the brain showed a slight increase in the fluid-attenuated inversion recovery (FLAIR) signal in the caudates and thalami (Fig. S1A and S1B in the Supplementary Appendix, available with the full text of this letter at NEJM.org). In January 2019, she became depressed and anxious and had memory impairment and visual hallucinations. There was hypertonia on the right side of her body. At that time, an analysis of CSF for 14-3-3 protein was negative. In March 2019, MRI showed an increased FLAIR signal in pulvinar and dorsomedial nuclei of thalami (Fig. S1C through S1E).
Figure 1.
Detection of Abnormal Prion Protein in Biologic Fluid Samples and Postmortem Findings.
The patient was found to be homozygous for methionine at codon 129 of the prion protein gene without mutation. An analysis of a sample of CSF on real-time quaking-induced conversion analysis was negative for a diagnosis of sporadic CJD. However, an analysis of plasma and CSF by means of protein misfolding cyclic amplification was positive for the diagnosis of variant CJD (Figure 1A and 1B). The patient died 19 months after the onset of symptoms. Neuropathological examination confirmed the diagnosis of variant CJD (Figure 1C and 1D). Western blot analysis showed the presence of type 2B protease-resistant prion protein in all sampled brain areas. The clinical characteristics of the patient and the postmortem neuropathological features were similar to those observed in 27 patients with variant CJD who had previously been reported in France.1 (Additional details are provided in the Supplementary Appendix.)
There are two potential explanations for this patient’s condition. Oral transmission from contaminated cattle products cannot be ruled out because the patient was born at the beginning of the French BSE outbreak in cattle. However, the last two patients who had confirmed variant CJD with methionine homozygosity at codon 129 in France and the United Kingdom died in 2014 and 2013, respectively, which makes oral transmission unlikely. In France, the risk of variant CJD in 2019 was negligible or nonexistent in the post-1969 birth cohort.2
Percutaneous exposure to prion-contaminated material is plausible in this patient, since the prion strain that she had handled was consistent with the development of variant CJD.3 The 7.5-year delay between the laboratory accident and her clinical symptoms is congruent with the incubation period in the transfusion-transmitted form of the disease. The ability of this strain to propagate through the peripheral route has been documented, and experimental studies with scrapie strains have shown that scarification and subcutaneous inoculation are effective routes.4,5 The last known Italian patient with variant CJD, who died in 2016, had had occupational contact with BSE-infected brain tissues, although subsequent investigation did not disclose a laboratory accident (Pocchiari M, Italian Registry of CJD: personal communication). Thus, the last two cases of variant CJD outside the United Kingdom have been associated with potential occupational exposure. Such cases highlight the need for improvements in the prevention of transmission of variant CJD and other prions that can affect humans in the laboratory and neurosurgery settings, as outlined in the Supplementary Appendix.
Jean-Philippe Brandel, M.D. Assistance Publique–Hôpitaux de Paris, Paris, France
M. Bustuchina Vlaicu, M.D. Groupe Hospitalier Nord-Essonne, Orsay, France
Audrey Culeux, B.Sc. INSERM Unité 1127, Paris, France
Maxime Belondrade, M.Sc. Daisy Bougard, Ph.D. Etablissement Français du Sang, Montpellier, France
Katarina Grznarova, Ph.D. Angeline Denouel, M.Sc. INSERM Unité 1127, Paris, France
Isabelle Plu, M.D. Elodie Bouaziz-Amar, Pharm.D., Ph.D. Danielle Seilhean, M.D., Ph.D. Assistance Publique–Hôpitaux de Paris, Paris, France
Michèle Levasseur, M.D. Groupe Hospitalier Nord-Essonne, Orsay, France
Stéphane Haïk, M.D., Ph.D. INSERM Unité 1127, Paris, France stephane.haik@upmc.fr
Supported by a grant (ANR-10-IAIHU-06) from Programme d’Investissements d’Avenir and Santé Publique France.
Disclosure forms provided by the authors are available with the full text of this letter at NEJM.org.
5 References
July 2, 2020
N Engl J Med 2020; 383:83-85
DOI: 10.1056/NEJMc2000687
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34 year old Doctor Orthopedic Surgeon dies from CJD
Dr. Adam Thomas Dialectos
1987 - 2021
BORN
April 29, 1987
DIED
June 21, 2021
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On Monday June 21, 2021, Dr. Adam Thomas Dialectos, loving husband, father, son, brother, uncle, Nouno, friend at the age of 34. Adam was born on April 29, 1987 in Reading, PA to Athan and Gretchen Dialectos. Adam was a 2005 graduate of Governor Mifflin High School, before receiving his degree in Health Sciences from James Madison University in 2009. Adam attended Philadelphia College of Osteopathic Medicine for medical school and his subsequent residency in orthopedic surgery. Adam was completing his Spine Surgery Fellowship at New England Baptist Hospital in Boston, Massachusetts. On February 7, 2019 Adam married the love of his life and girlfriend of 12 years, Lindsey (Schuler) Dialectos. They brought a beautiful baby boy into this world on January 6, 2021, Athananosis Adam Dialectos. Adam’s passion in life was unceasingly seeking to help others, emphasized by his desire to be a surgeon— a decision he made in his early elementary years. Adam continued this love of medicine throughout his life, which led to his achieving of the Henrietta and Jack Avart Memorial Award in 2019, awarded to the Orthopedic surgery resident who exhibited unparalleled excellence in their field during the residency program. This passion to learn, teach and support was truly understood through the patients whose lives Adam touched. When it came to his patients and coworkers, there was never a job too small for Adam. Those who knew Adam saw his personality shine through in so many other aspects of his life. Adam loved traveling. Some of his most memorable trips were with his wife, and countless snowboard trips with his brother, family, and friends. Adam loved everyone he was around; he loved and was loved by so many. Adam was truly one in a million. Adam is survived by his loving wife, Lindsey, and their son, Athan Adam; His father and mother, Athan and Gretchen; His brother Jordan and sister-in-law Megan, and their daughter Livia, Adam’s Goddaughter. His sister, Rachel, and her significant other, Bo Wagner. Furthermore, Adam is survived by his Yiayia, Joanne Dialectos, wife of the late George Dialectos; his Pop Pop, Donald Harford, husband of the late Nancy Servent; his Aunt Angel and Uncle Scott Helm; his Aunt Kelly and Uncle Darrell Markley. Adam was preceded in death by his Aunt Maria and Uncle Bob Care. Funeral Service will be held at Saints Constantine & Helen Greek Orthodox Church, 1001 East Wyomissing Blvd. Reading on Thursday June 24th. Father Theodore Petrides and Father Thomas L. Pappalas will officiate. Interment will follow at Charles Evans Cemetery. The family will receive relatives and friends at Saints Constantine & Helen Greek Orthodox Church from 9:00am to 11:00am with services beginning at 11:00. In lieu of flowers, contributions may be made to the CJD Foundation at 3634 West Market Street Suite 110 Akron, Ohio 44333 or cjdfoundation.org in remembrance of Dr. Adam Dialectos. Donations may also be made to Saints Constantine & Helen Greek Orthodox Church. Bean Funeral Home, 1605 Rockland Street, Hampden Heights, is in charge of arrangements and online condolences may be made at www.beanfuneralhomes.com.
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Published by Reading Eagle from Jun. 22 to Jun. 24, 2021.
Our sincere condolences to the Family and Friends of Dr. Adam Thomas Dialectos.
I can't help but ponder, as a Orthopedic Surgeon, Spine Surgery Fellowship, and what the good Doctors work curtailed, i can't help but think this is a potential case of iatrogenic CJD. surgery on humans, i would imagine cadavers as well.
all iatrogenic cjd is, is sporadic cjd, before the iatrogenic event is discovered, traced back, provern, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic cjd. ...terry
least we forget...
*** Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery ***
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892. Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8006664&dopt=Abstract
Friday, February 19, 2021
Preclinical transmission of prions by blood transfusion is influenced by donor genotype and route of infection
***> 2021
Wide distribution of prion infectivity in the peripheral tissues of vCJD and sCJD patients
Jean‑Yves Douet1 · Alvina Huor1 · Hervé Cassard1 · Séverine Lugan1 · Naima Aron1 · Mark Arnold2 · Didier Vilette1 · Juan‑Maria Torres3 · James W. Ironside4 · Olivier Andreoletti1
Received: 17 December 2020 / Revised: 18 January 2021 / Accepted: 19 January 2021 © The Author(s) 2021
Abstract
Sporadic Creutzfeldt-Jakob disease (sCJD) is the commonest human prion disease, occurring most likely as the consequence of spontaneous formation of abnormal prion protein in the central nervous system (CNS). Variant Creutzfeldt–Jakob disease (vCJD) is an acquired prion disease that was first identified in 1996. In marked contrast to vCJD, previous investigations in sCJD revealed either inconsistent levels or an absence of PrPSc in peripheral tissues. These findings contributed to the consensus that risks of transmitting sCJD as a consequence of non-CNS invasive clinical procedures were low. In this study, we systematically measured prion infectivity levels in CNS and peripheral tissues collected from vCJD and sCJD patients. Unexpectedly, prion infectivity was detected in a wide variety of peripheral tissues in sCJD cases. Although the sCJD infectivity levels varied unpredictably in the tissues sampled and between patients, these findings could impact on our perception of the possible transmission risks associated with sCJD.
snip...
Recently, bioassays in transgenic mice that express the human PrP gene and display a high sensitivity to sCJD demonstrated the presence of prion infectivity in the plasma and bone marrow of several sCJD patients [17, 32]. These results raised questions about the overall distribution of prion infectivity and transmission risks associated with other peripheral tissues from sCJD patients.
In this study, we measured the prion infectivity levels in a panel of tissues collected from vCJD and sCJD MM1 cases. These bioassays demonstrated that, as expected, consistent titres of infectivity were present in lymphoid tissues from vCJD patients. However, for the non-lymphoid peripheral tissues studied, variable and lower titres of infectivity were detected in both sCJD and vCJD patients. These findings could impact on our perception of the possible transmission risks associated with sCJD involving non-CNS invasive procedures.
snip...
In the sCJD cases 2, 4 and 5, the lymphoid tissues dis-played maximal level of infectivity that were 3–3.5 log10 lower than those observed in the frontal cortex (Table 2, Fig. 3). Strikingly, the infectivity levels associated with some peripheral tissues such as salivary gland (sCJD2), heart (sCJD2), kidney (sCJD 2) or bone marrow (sCJD 5) could be equivalent or even higher than those measured in the lymphoid organs of the same patient (Table 2, Fig. 3).
Our detection of low levels of sCJD infectivity in nonCNS tissues such as lung, heart, muscle or even salivary gland was unexpected. We next reviewed the medical histories for the sCJD patients that we studied (Table 1), which revealed surgical procedures (s-CJD-2 and 4) and/or invasive medical examinations (polypectomy under colonoscopy sCJD-5) only few years before the clinical disease in these patients. Some years ago, the presence of infectivity in the plasma and the detection of abnormal prion protein in the urine of sCJD patients raised concerns about the risks of sCJD transmission by blood transfusion and plasma/urinederived medical products [17, 38]. The detection, in our study, of infectivity in the bone marrow and the kidney of sCJD patients further reinforces these concerns.
Many uncertainties remain on the early stages of the prion accumulation and infectivity in the peripheral tis-sues in patients infected with sCJD. However, the results of this study suggest that the iatrogenic transmission risks associated with sCJD peripheral tissues should not be disregarded.
Subclinical infection occurs frequently following low dose exposure to prions by blood transfusion Published: 28 June 2022
Subclinical infection occurs frequently following low dose exposure to prions by blood transfusion
M. Khalid F. Salamat, Paula Stewart, Helen Brown, Kyle B. C. Tan, Allister Smith, Christopher de Wolf, A. Richard Alejo Blanco, Marc Turner, Jean C. Manson, Sandra McCutcheon & E. Fiona Houston
Scientific Reports volume 12, Article number: 10923 (2022)
Abstract
Infectious prion diseases have very long incubation periods, and the role that subclinical infections play in transmission, persistence and re-emergence of these diseases is unclear. In this study, we used a well-established model of vCJD (sheep experimentally infected with bovine spongiform encephalopathy, BSE) to determine the prevalence of subclinical infection following exposure by blood transfusion from infected donors. Many recipient sheep survived for years post-transfusion with no clinical signs and no disease-associated PrP (PrPSc) found in post mortem tissue samples by conventional tests. Using a sensitive protein misfolding cyclic amplification assay (PMCA), we found that the majority of these sheep had detectable PrPSc in lymph node samples, at levels approximately 105–106 times lower than in equivalent samples from clinically positive sheep. Further testing revealed the presence of PrPSc in other tissues, including brain, but not in blood samples. The results demonstrate that subclinical infection is a frequent outcome of low dose prion infection by a clinically relevant route for humans (blood transfusion). The long term persistence of low levels of infection has important implications for prion disease control and the risks of re-emergent infections in both humans and animals.
snip...
Our study demonstrates for the first time that subclinical infection is a common outcome following low dose exposure to prions by a clinically relevant transmission route (blood transfusion), and can persist in hosts until close to their natural lifespan. By analogy, it is plausible that subclinical vCJD may occur in human patients who have been similarly exposed, and this could account for some of the IHC positive appendix samples identified in previous surveys. Importantly, we found that PrPSc amplification was essential for detecting subclinical infections in our study, supporting the case for targeted use of techniques such as PMCA and RT-QuIC in surveillance, to estimate prevalence of infection. Further research using animal models is vital to establish infection transmission risks associated with subclinical infection, and the role of subclinical infection in maintenance and re-emergence of prion diseases in animal and human populations.
Thursday, June 15, 2023
nvCJD or vCJD TSE PrP, and Blood, updated information
2023
OIE Conclusions on transmissibility of atypical BSE among cattle
Given that cattle have been successfully infected by the oral route, at least for L-BSE, it is reasonable to conclude that atypical BSE is potentially capable of being recycled in a cattle population if cattle are exposed to contaminated feed. In addition, based on reports of atypical BSE from several countries that have not had C-BSE, it appears likely that atypical BSE would arise as a spontaneous disease in any country, albeit at a very low incidence in old cattle. In the presence of livestock industry practices that would allow it to be recycled in the cattle feed chain, it is likely that some level of exposure and transmission may occur. As a result, since atypical BSE can be reasonably considered to pose a potential background level of risk for any country with cattle, the recycling of both classical and atypical strains in the cattle and broader ruminant populations should be avoided.
Annex 7 (contd) AHG on BSE risk assessment and surveillance/March 2019
34 Scientific Commission/September 2019
3. Atypical BSE
The Group discussed and endorsed with minor revisions an overview of relevant literature on the risk of atypical BSE being recycled in a cattle population and its zoonotic potential that had been prepared ahead of the meeting by one expert from the Group. This overview is provided as Appendix IV and its main conclusions are outlined below. With regard to the risk of recycling of atypical BSE, recently published research confirmed that the L-type BSE prion (a type of atypical BSE prion) may be orally transmitted to calves1 . In light of this evidence, and the likelihood that atypical BSE could arise as a spontaneous disease in any country, albeit at a very low incidence, the Group was of the opinion that it would be reasonable to conclude that atypical BSE is potentially capable of being recycled in a cattle population if cattle were to be exposed to contaminated feed. Therefore, the recycling of atypical strains in cattle and broader ruminant populations should be avoided.
4. Definitions of meat-and-bone meal (MBM) and greaves
Wednesday, May 24, 2023
***> WAHIS, WOAH, OIE, United States of America Bovine spongiform encephalopathy Immediate notification
https://wahis.woah.org/#/in-review/5067
https://woahoie.blogspot.com/2023/05/wahis-woah-oie-united-states-of-america.html
https://prpsc.proboards.com/thread/125/wahis-woah-oie-immediate-notification
SATURDAY, MAY 20, 2023
***> Tennessee State Veterinarian Alerts Cattle Owners to Disease Detection Mad Cow atypical L-Type BSE
https://bse-atypical.blogspot.com/2023/05/tennessee-state-veterinarian-alerts.html
https://prpsc.proboards.com/thread/123/tennessee-veterinarian-alerts-cattle-confirmed
MAY 19, 2023
https://www.aphis.usda.gov/aphis/newsroom/stakeholder-info/sa_by_date/sa-2023/bse
2 weeks before the announcement of this recent mad cow case in the USA, i submitted this to the APHIS et al;
***> APPRX. 2 weeks before the recent mad cow case was confirmed in the USA, in Tennessee, atypical L-Type BSE, I submitted this to the APHIS et al;
Document APHIS-2023-0027-0001 BSE Singeltary Comment Submission May 2, 2023
''said 'burden' cost, will be a heavy burden to bear, if we fail with Bovine Spongiform Encephalopathy BSE TSE Prion disease, that is why this information collection is so critical''...
https://www.regulations.gov/comment/APHIS-2023-0027-0002
https://downloads.regulations.gov/APHIS-2023-0027-0002/attachment_1.pdf
spontaneous my ass, big outbreak of spontaneous mad cow disease evidently, around the same time, strange;
WEDNESDAY, NOVEMBER 08, 2023
Ireland Atypical BSE confirmed November 3 2023
https://bse-atypical.blogspot.com/2023/11/ireland-atypical-bse-confirmed-november.html
TUESDAY, NOVEMBER 14, 2023
Ireland Atypical BSE case, 3 progeny of case cow to be culled
https://bse-atypical.blogspot.com/2023/11/ireland-atypical-bse-case-3-progeny-of.html
SUNDAY, JULY 16, 2023
Switzerland Atypical BSE detected in a cow in the canton of St. Gallen
https://bse-atypical.blogspot.com/2023/07/switzerland-atypical-bse-detected-in.html
WAHIS, WOAH, OIE, REPORT Switzerland Bovine Spongiform Encephalopathy Atypical L-Type
Switzerland Bovine Spongiform Encephalopathy Atypical L-Type
Switzerland - Bovine spongiform encephalopathy - Immediate notification
https://wahis.woah.org/#/in-review/4962
https://bse-atypical.blogspot.com/2020/02/switzerland-oie-bovine-spongiform.html
Monday, March 20, 2023
WAHIS, WOAH, OIE, REPORT United Kingdom Bovine Spongiform Encephalopathy Atypical H-Type
https://wahis.woah.org/#/in-review/4977
https://www.gov.uk/government/news/single-case-of-atypical-bse-confirmed-on-a-farm-in-cornwall
https://woahoie.blogspot.com/2023/03/wahis-woah-oie-report-united-kingdom.html
https://woahoie.blogspot.com/2023/03/wahis-woah-oie-report-united-kingdom.html
BRAZIL BSE START DATE 2023/01/18
BRAZIL BSE CONFIRMATION DATE 2023/02/22
BRAZIL BSE END DATE 2023/03/03
https://wahis.woah.org/#/in-review/4918
https://bse-atypical.blogspot.com/2019/06/brazil-reports-another-cases-of-mad-cow.html
SPAIN BSE START DATE 2023/01/21
SPAIN BSE CONFIRMATION DATE 2023/02/03
SPAIN BSE END DATE 2023/02/06
https://wahis.woah.org/#/in-review/4888
https://bse-atypical.blogspot.com/2023/02/spain-bovine-spongiform-encephalopathy.html
NETHERLANDS BSE START DATE 2023/02/01
NETHERLANDS BSE CONFIRMATION DATE 2023/02/01
NETHERLANDS BSE END DATE 2023/03/13
https://wahis.woah.org/#/in-review/4876
https://bse-atypical.blogspot.com/2023/02/netherlands-bovine-spongiform.html
PLEASE NOTE, USDA ET AL ONLY TESTING <25k CATTLE FOR MAD COW DISEASE, woefully inadequate, yet USDA just documented a case Atypical L-Type BSE, the most virulent strain to date...
Monday, May 22, 2023
***> BSE TSE Prion MAD COW TESTING IN THE USA COMPARED TO OTHER COUNTRIES?
TUESDAY, NOVEMBER 28, 2023
EFSA TSE Report 2022 First published 28 November 2023 The European Union summary report on surveillance for the presence of transmissible spongiform encephalopathies (TSE) in 2022
THURSDAY, DECEMBER 7, 2023
Chronic Wasting Disease CWD TSE Prion Cervid Update By State December 2023 (Long Version)
(Short Version)
WEDNESDAY, FEBRUARY 28, 2024
GAO-02-183 Mad Cow Disease: Improvements in the Animal Feed Ban and Other Regulatory Areas Would Strengthen U.S. Prevention Efforts February 26, 2002
Professor John Collinge on tackling prion diseases, sCJD accounts for around 1 in 5000 deaths worldwide
MONDAY, SEPTEMBER 11, 2023
Professor John Collinge on tackling prion diseases
“The best-known human prion disease is sporadic Creutzfeldt-Jakob disease (sCJD), a rapidly progressive dementia which accounts for around 1 in 5000 deaths worldwide.”
There is accumulating evidence also for iatrogenic AD. Understanding prion biology, and in particular how propagation of prions leads to neurodegeneration, is therefore of central research importance in medicine.
MONDAY, DECEMBER 18, 2023
Change in Epidemiology of Creutzfeldt-Jakob Disease in the US, 2007-2020
TUESDAY, DECEMBER 12, 2023
CREUTZFELDT JAKOB DISEASE TSE PRION DISEASE UPDATE USA DECEMBER 2023
SUNDAY, NOVEMBER 26, 2023
The role of environmental factors on sporadic Creutzfeldt-Jakob disease mortality: evidence from an age-period-cohort analysis
FRIDAY, JANUARY 31, 2020
CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF? Docket Number: FDA-2012-D-0307
Thursday, June 3, 2021
CWD TSE PRION ZOONOSIS TRANSMISSION TO HUMANS BY BLOOD TRANSFUSION, iatrogenic CJD, WHAT IF?
Terry S. Singeltary Sr.
