Thursday, May 23, 2019

Prion 2019 Emerging Concepts CWD, BSE, SCRAPIE, CJD, SCIENTIFIC PROGRAM Schedule and Abstracts

Prion 2019 Emerging Concepts

Prion 2019 Congress Full Schedule


8:30 - 12:05 WORKSHOP 1: Animal Prion Disease-Interspecies Transmission

WORKSHOP ORGANIZERS: Debbie McKenzie, Judd Aiken, Olivier Andreoletti

Moved from Salon 4 to Salon 8

8:30 - 8:35 Welcome

8:35 - 9:05 Interspecies transmission of the chronic wasting disease agent

Justin Greenlee, USDA, ARS, National Animal Disease Center, Ames, Iowa, USA

9:05 - 9:20 Evaluation of interspecies transmission potential of different CWD isolates

Rodrigo Morales, University of Texas Health Science Center, San Antonio, Texas, USA

 9:20 - 9:35 CWD transmissibility to humans: Investigation using humanized mouse models and sCJD tissues

Qingzhong Kong, Case Western Reserve University, Cleveland, Ohio, USA

9:35 - 9:50 Chronic wasting disease transmission studies to non-human primates & transgenic mice

Brent Race, Rocky Mountain Labs, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA

9:50 - 10:05 Alteration of prion strain emergence by non-host factors

Sara Holec, Creighton University, Omaha, Nebraska, USA

10:05 - 10:20 HOSPITALITY BREAK Salon 8

10:20 - 10:35 Establishment of PrPCWD extraction and detection in farm soil

Hyun Joo Sohn, Animal and Plant Quarantine Agency, South Korea

10:35 - 10:50 Detection of CWD prion seeding activity in feces demonstrates both consistent shedding and potential for environmental monitoring

Joanne Tennant, Colorado State University, Fort Collins, Colorado, USA

10:50 - 11:05 Longitudinal Studies of CWD Infection After Low-Dose Exposure

Ed Hoover, Colorado State University, Fort Collins, Colorado, USA

11:05 - 11:20 Detection of hematogenous prions in longitudinal CWD studies

Amy Nalls, Prion Research Centre, Colorado State University, Fort Collins, Colorado, USA

11:20 - 11:35 Identification of novel CWD strains

Debbie McKenzie, University of Alberta, Edmonton, Canada

11:35 - 11:50 Mixtures of prion substrains in mice bioassay of natural scrapie cases

Rosa Bolea, University of Zaragoza, Centre for TSE and Emerging Animal Diseases, Zaragoza, Spain

11:50 - 12:05 Structural analyses of chronic wasting disease using electron microscopy and molecular dynamics simulations

Sara Amidian, University of Alberta, Edmonton, Canada

12:05 - 12:20 PrPSc aggregation state dictates biochemical properties of prions and disease pathogenesis

Chris Chang, CPRU, University of Calgary, Calgary, Canada

12:20 - 1:00 BUFFET LUNCH Salon 8

SCHEDULE: TUESDAY, MAY 21 Workshops have been moved from Salon 4 to Salon 8

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1:00 - 5:00 WORKSHOP 2: Biomarkers and Diagnostics for Protein Folding Diseases

WORKSHOP ORGANIZERS: Inga Zerr, Kurt Giles, Sonia Vallabh

1:00 - 1:30 Seed amplification assays for diagnosis, etiological biomarker measurement, and strain discrimination in protein folding diseases

Byron Caughey, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA

1:30 - 1:50 Ultrasensitive detection and seeding selectivity of tau aggregates of Alzheimer disease and chronic traumatic encephalopathy

Alison Kraus, Rocky Mountain Laboratories, National Institutes of Health, Hamilton, Montana, USA

 1:50 - 2:10 Diagnosis and biomarkers of Parkinson’s and Dementia with Lewy bodies: rapid and ultra-sensitive quantitation of disease-associated α-synuclein by αSyn RT-QuIC

Christina Orru, Rocky Mountain Laboratories, National Institutes of Health, Hamilton, Montana, USA

2:10 - 2:30 Skin biomarkers as diagnostic tests across neurodegenerative diseases

Wen-Quan Zou, Case Western Reserve University, Cleveland, Ohio, USA

2:30 - 2:50 Neurofilament light chain (NfL) as a possible biomarker for drug efficacy in mouse models of neurodegenerative diseases

Masakazu Hirouchi, University of California, San Franscisco, California, USA

2:50 - 3:10 HOSPITALITY BREAK Salon 8

3:10 - 3:30 Diagnostic accuracy of cerebrospinal fluid RT-QuIC in cases of suspected prion disease and the potential utility of using RT-QuIC for public health surveillance

Brian Appleby, Case Western Reserve University, Cleveland, Ohio, USA

3:30 - 3:50 Domain-specific quantification of PrP in cerebrospinal fluid by targeted mass spectrometry

Eric Minikel, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA

3:50 - 4:10 Conversion kinetics of sporadic CJD prions using multiple substrates and RT-QuIC-based detection and discrimination

Stephanie Booth, Public Health Agency of Canada, Ottawa, Canada

4:10 - 4:30 High efficiency detection of all prion subtypes of sporadic Creutzfeldt Jakob disease by PMCA

Sandra Prizkow, The University of Texas Health Science Center at Houston, Houston, Texas, USA

4:30 - 4:50 Utility of RT-QuIC in predicting case status of potential Creutzfeldt-Jakob Disease (CJD) cases

Natalie Marzec, Colorado Department of Public Health and Environment, Denver, Colorado, USA

5:30 - 6:30 PRION STRAIN PHENOMENA 2019 – two perspectives; a presentation to assess the progress of prion strain concepts

CHAIR: Jason Bartz

John Collinge, University College London, London, England Surachai Supattapone, Dartmouth College, New Hampshire, USA

Salon 9

6:30 - 8:00 WELCOME RECEPTION Hall D Foyer


7:30 - 8:15 BREAKFAST Foyer, Hall D

8:15 - 8:30 WELCOME

David Westaway, Hermann Schaetzl, Kevin Keough

Co-Chairs, PRION 2019 Congress

Hall D


CHAIRS: D. Riesner & G. Legname

Hall D

8:30 - 9:10 Structural insights into the mechanism of mammalian prion propagation

Witold K. Surewicz, Case Western Reserve University, Cleveland, USA

9:10 - 9:30 Full atomistic model of PrPSc structure and conversion

G. Spagnolli, CIBIO, University of Trento, Trento, Italy

9:30 - 9:50 A shared β-solenoid structure for all PrPSc strains tested

H. Wille, CPPFD, University of Alberta, Edmonton, Canada

9:50 - 10:10 Large-scale production of recombinant prions with high specific infectivity

D. Walsh, Dartmouth College, Hanover, New Hampshire, USA


10:30 - 12:10 HUMAN DISEASE 1

CHAIRS: A. Rozemuller & B. Appleby

Hall D

10:30 - 11:10 Seed-induced Aβ deposition impairs adult neurogenesis in mouse models of Alzheimer’s disease

Melanie Meyer-Luehmann, Universitats Klinikum-Freiburg, Freiburg, Germany

11:10 - 11:30 Critical impact of cofactors on transmissibility of human prions

J. Safar, Case Western Reserve University, Cleveland, Ohio, USA

11:30 - 11:50 Investigating the clinical correlation between sCJD and other neurodegenerative pathologies

J. Lumsden, National CJD Research and Surveillance Unit, University of Edinburgh, Edinburgh, Scotland

11:50 - 12:10 sCJD Prions Distribute throughout the Eye

C. Orru, Rocky Mountain Labs, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA

12:10 - 12:55 LUNCH Foyer, Hall D


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12:55 - 2:35 ANIMAL DISEASE 1

CHAIRS: G. Telling & M. Zabel

Hall D

12:55 - 1:35 Modifying prion spread through the CNS

Christina Sigurdson, University of California, San Diego, USA

1:35 - 1:55 Cervid Prnp polymorphism at codon 116 generates new and distinct CWD strains

S. Hannaoui, CPRU, University of Calgary, Calgary, Canada

1:55 - 2:15 Binding prions to soils impact PrPCWD recovery but not infectivity

A. Kuznetsova, CPPFD, University of Alberta, Edmonton, Canada

2:15 - 2:35 Diversity of chronic wasting disease prion strains

C. Duque Velásquez, CPPFD, University of Alberta, Edmonton, Canada


2:55 - 4:35 CELL BIOLOGY 1

CHAIRS: C. Lasmezas & M. Horiuchi

Hall D

2:55 - 3:35 Drivers of neurotoxicity in prion diseases

Adriano Aguzzi, University Hospital Zurich, Zurich, Switzerland

3:35 - 3:55 Pathological consequences of ROCK-PDK1 kinases overactivation in prion diseases

B. Schneider, Université Paris Descartes - Inserm, Paris, France

3:55 - 4:15 Human cerebral organoids propagate sporadic CJD prions

C. Haigh, National Institute of Alergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA

4:15 - 4:35 How the PrPC C-terminal domain regulates its toxic N-terminal domain

G. Millhauser, University of California, Santa Cruz, USA

4:40 - 5:55 PRION 2019 DEBATE: PrPC function in the brain

CHAIR: James Hope

PARTICIPANTS: A. Aguzzi, C. Haigh, G. Millhauser, G. Schmitt-Ulms

Hall D


*Cash Bar

Hall D


PRION 2019

7:30 - 8:15 BREAKFAST Foyer


8:25 - 10:05 OTHER PRIONS

CHAIRS: H. True & J. Ma

Hall D

8:25 - 9:05 Targeting proteopathic seeds in Alzheimer’s disease

Mathias Jucker, University Tübingen, Tübingen, Germany

9:05 - 9:25 Seeding Aβ accelerates AD-like pathology without cognitive impairment

S. G. Lacoursiere, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Canada

9:25 - 9:45 Alpha-synuclein strains initiate distinct transmissable synucleinopathies

J. Watts, Tanz Centre, University of Toronto, Toronto, Canada

9:45 - 10:05 Multiple sclerosis brain transmits pathology to humanized transgenic mice

S. Tsutsui, HBI, Cumming School of Medicine, University of Calgary, Calgary, Canada


10:25 - 12:05 ANIMAL DISEASE 2

CHAIRS: C. Mathiason & M. Beekes

Hall D

10:25 - 11:05 Prion accumulation in the Bone Marrow: the origin of Prionemia?

Olivier Andreoletti, École Nationale Vétérinaire de Toulouse, Toulouse, France

11:05 - 11:25 BSE discrimination and geographical variation of goat scrapie

R. Nonno, Istituto Superiore di Sanità, Rome, Italy

11:25 - 11:45 Prion tropism for the spleen: role of PrPC expression levels 

V. Béringue, VIM, INRA, Université Paris-Saclay, Jouy-en-Josas, France

11:45 - 12:05 Rapid bioassay of mammalian prions in Drosophila

R. Bujdoso, Cambridge University, Cambridge, United Kingdom





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CHAIRS: S. Priola & K. Doh-ura

Hall D

1:55 - 2:55 Arguments for Alzheimer’s and Parkinson’s Diseases Being Caused by Prions

Stanley B. Prusiner, Institute for Neurodegenerative Diseases, University of California, San Francisco, USA

2:55 - 3:15 Antisense oligonucleotides for the prevention of genetic prion disease

S. Vallabh, Broad Institute of Harvard and MIT, Massachusetts, USA

3:15 - 3:35 Substrate-specific manipulation of the ADAM10-mediated shedding of PrPC

L. Linsenmeier, Institute of Neuropathology, UKE Hamburg, Germany

3:35 - 3:55 Evaluating plasma tau and NfL as biomarkers for prion disease

A. Thompson, MRC Prion Unit, University College London, London, United Kingdom



4:45 - 6:05 GENETICS

CHAIR: R. Wickner

Hall D

4:45 - 5:25 Genetic risk factors for sporadic CJD: replication, expression, function

Simon Mead, University College London, London, United Kingdom

5:25 - 5:45 Familial Parkinson’s point mutation abolishes multiple system atrophy prion replication

A. Woerman, University of California, San Franscisco, California, USA

5:45 - 6:05 Potential insights into avoiding amyloidosis from the functional amyloid PMEL

T. Allison, CPPFD, University of Alberta, Edmonton, Canada

7:00 - 10:00 ART GALLERY OF ALBERTA RECEPTION Art Gallery of Alberta


PRION 2019

7:30 - 8:15 BREAKFAST Foyer



CHAIRS: B. Sykes & C. Soto

Hall D

8:25 - 9:05 A Solid-state Conceptualization of Information Transfer from Gene to Message to Protein

Steve McKnight, University of Texas Southwestern, Dallas, Texas, USA

9:05 - 9:25 Purification of small, non-fibrillar and infectious prions from GSS disease

I. Vanni, Istituto Superiore di Sanità, Rome, Italy

9:25 - 9:45 Seeding ability of olfactory mucosa samples from patients with synucleinopathies

F. Moda, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy

9:45 - 10:05 Generation of bona fide prions by large-scale PMCA

F. Wang, University of Texas Health, Houston, Texas, USA


10:25 - 12:05 HUMAN DISEASE 2

CHAIRS: P. Parchi & W.-Q. Zou

Hall D

10:25 - 11:05 Beyond Neurofibrillary Tangles in Tauopathy

Karen Ashe, University of Minnesota, Mineapolis, Minnesota, USA

11:05 - 11:25 microRNAs profiling identifies a novel signature associated with sCJD progression

E. Vire, Institute of Prion Diseases, University College London, United Kingdom

11:25 - 11:45 Anti-PrPC autoantibodies in PRNP mutation carriers

K. Frontzek, University of Zurich, Zurich, Switzerland

11:45 - 12:05 Diverse Tau signatures in an inbred model mimic heterogeneity in a primary Tauopathy

D. Westaway, CPPFD, University of Alberta, Edmonton, Canada




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NeuroPrion members

Hall D

1:50 - 3:30 CELL BIOLOGY 2

CHAIRS: V. Lawson & J. Braun

Hall D

1:50 - 2:30 Cellular prion infection: from traffic jams to new drug targets

Sabine Gilch, University of Calgary, Calgary, Canada

2:30 - 2:50 Propagation of human sCJD prions in organotypic slice culture

V. Sim, CPPFD, University of Alberta, Edmonton, Canada

2:50 - 3:10 Hsp110 modifies prion infection in vitro and in vivo

C. Marrero-Winkens, CPRU, University of Calgary, Calgary, Canada

3:10 - 3:30 The FXR1 Protein Is A Functional Amyloid Of Mammalian Brain

A. Sergeeva, St. Petersburg State University, Department of Genetics and Biotechnology, St. Petersburg, Russia


3:50 - 4:50 LATE BREAKING NEWS Hall D

3:50 - 4:02 CWD in a 16-year-old moose in Sweden

Maria Nöremark, National Veterinary Institute, Uppsala, Sweden

4:02 - 4:14 Generation of chemically optimized molecules suppressing PrP toxicity

Emiliano Biasini, University of Trento, Trento, Italy

4:14 - 4:26 A first glimpse of infectious recombinant PrPSc using solid state NMR

Jesús Requena, University of Santiago de Compostela, Spain

4:26 - 4:38 Nascent β-structure in the hydrophobic region of a GSS PrP allele

Z.-L. Fu, University of Alberta, Edmonton, Canada

4:38 - 4:50 Covalently-linked PrP fragments in two major GSS variants

Laura Cracco, Case Western Reserve University, Cleveland, USA



CO-CHAIRS: D. Westaway and H. Schaetzl


here are a few of the abstracts on CHRONIC WASTING DISEASE CWD TSE PRION...terry


1. Interspecies transmission of the chronic wasting disease agent

Justin Greenlee

Virus and Prion Research Unit, National Animal Disease Center, USDA Agriculture Research Service


The presentation will summarize the results of various studies conducted at our research center that assess the transmissibility of the chronic wasting disease (CWD) agent to cattle, pigs, raccoons, goats, and sheep. This will include specifics of the relative attack rates, clinical signs, and microscopic lesions with emphasis on how to differentiate cross-species transmission of the CWD agent from the prion diseases that naturally occur in hosts such as cattle or sheep. Briefly, the relative difficulty of transmitting the CWD agent to sheep and goats will be contrasted with the relative ease of transmitting the scrapie agent to white-tailed deer.

53. Evaluation of the inter-species transmission potential of different CWD isolates

Rodrigo Moralesa, Carlos Kramma,b, Paulina Sotoa, Adam Lyona, Sandra Pritzkowa, Claudio Sotoa

aMitchell Center for Alzheimer’s disease and Related Brain Disorders, Dept. of Neurology, McGovern School of Medicine University of Texas Health Science Center at Houston, TX, USA; bFacultad de Medicina, Universidad de los Andes, Santiago, Chile


Chronic Wasting Disease (CWD) has reached epidemic proportions in North America and has been identified in South Korea and Northern Europe. CWD-susceptible cervid species are known to share habitats with humans and other animals entering the human food chain. At present, the potential of CWD to infect humans and other animal species is not completely clear. The exploration of this issue acquires further complexity considering the differences in the prion protein sequence due to species-specific variations and polymorphic changes within species. While several species of cervids are naturally affected by CWD, white-tailed deer (WTD) is perhaps the most relevant due to its extensive use in hunting and as a source of food. Evaluation of inter-species prion infections using animals or mouse models is costly and time consuming. We and others have shown that the Protein Misfolding Cyclic Amplification (PMCA) technology reproduces, in an accelerated and inexpensive manner, the inter-species transmission of prions while preserving the strain features of the input PrPSc. In this work, we tested the potential of different WTD-derived CWD isolates to transmit to humans and other animal species relevant for human consumption using PMCA. For these experiments, CWD isolates homozygous for the most common WTD-PrP polymorphic changes (G96S) were used (96SS variant obtained from a pre-symptomatic prion infected WTD). Briefly, 96GG and 96SS CWD prions were adapted in homologous or heterologous substrate by PMCA through several (15) rounds. End products, as well as intermediates across the process, were tested for their inter-species transmission potentials. A similar process was followed to assess seed-templated misfolding of ovine, porcine, and bovine PrPC. Our results show differences on the inter-species transmission potentials of the four adapted materials generated (PrPC/PrPSc polymorphic combinations), being the homologous combinations of seed/substrate the ones with the greater apparent zoonotic potential. Surprisingly, 96SS prions adapted in homologous substrate were the ones showing the easiest potential to template PrPC misfolding from other animal species. In summary, our results show that a plethora of different CWD isolates, each comprising different potentials for inter-species transmission, may exist in the environment. These experiments may help to clarify an uncertain and potentially worrisome public health issue. Additional research in this area may be useful to advise on the design of regulations intended to stop the spread of CWD and predict unwanted zoonotic events.

56. Understanding chronic wasting disease spread potential for at-risk species

Catherine I. Cullingham, Anh Dao, Debbie McKenzie and David W. Coltman

Department of Biological Sciences, University of Alberta, Edmonton AB, Canada

CONTACT Catherine I. Cullingham


Genetic variation can be linked to susceptibility or resistance to a disease, and this information can help to better understand spread-risk in a population. Wildlife disease incidence is increasing, and this is resulting in negative impacts on the economy, biodiversity, and in some instances, human health. If we can find genetic variation that helps to inform which individuals are susceptible, then we can use this information on at-risk populations to better manage negative consequences. Chronic wasting disease, a fatal, transmissible spongiform encephalopathy of cervids (both wild and captive), continues to spread geographically, which has resulted in an increasing host-range. The disease agent (PrPCWD) is a misfolded conformer of native cellular protein (PrPC). In Canada, the disease is endemic in Alberta and Saskatchewan, infecting primarily mule deer and white-tail deer, with a smaller impact on elk and moose populations. As the extent of the endemic area continues to expand, additional species will be exposed to this disease, including bison, bighorn sheep, mountain goat, and pronghorn antelope. To better understand the potential spread-risk among these species, we reviewed the current literature on species that have been orally exposed to CWD to identify susceptible and resistant species. We then compared the amino acid polymorphisms of PrPC among these species to determine whether any sites were linked to susceptibility or resistance to CWD infection. We sequenced the entire PrP coding region in 578 individuals across at-risk populations to evaluate their potential susceptibility. Three amino acid sites (97, 170, and 174; human numbering) were significantly associated with susceptibility, but these were not fully discriminating. All but one species among the resistant group shared the same haplotype, and the same for the susceptible species. For the at-risk species, bison had the resistant haplotype, while bighorn sheep and mountain goats were closely associated with the resistant type. Pronghorn antelope and a newly identified haplotype in moose differed from the susceptible haplotype, but were still closely associated with it. These data suggest pronghorn antelope will be susceptible to CWD while bison are likely to be resistant. Based on this data, recommendations can be made regarding species to be monitored for possible CWD infection.

KEYWORDS: Chronic wasting disease; Prnp; wildlife disease; population genetics; ungulates

60. Caribou Prnp polymorphism distribution in Canada and its impact on CWD pathogenesis

Maria I. Arifina, Samia Hannaouia, Yuan-Hung Huanga, Gordon Mitchellb, Antanas Staskeviciusb, Lech Kaczmarczykc,d, Walker Jacksonc,d and Sabine Gilcha

aDepartment of Ecosystem and Public Health, University of Calgary; bNational and OIE Reference Laboratory for Scrapie and CWD, Ottawa Laboratory Fallowfield, Canadian Food Inspection Agency; cWallenberg Center for Molecular Medicine, Department of Clinical and Experimental Medicine, Linköping University; dGerman Center for Neurodegenerative Disease (DZNE), Bonn

CONTACT Maria I. Arifin


Wild reindeer in Norway were recently diagnosed with chronic wasting disease (CWD) [1]. Prions from CWD-infected deer were also transmissible to other reindeer in experimental settings [2,3]. Although CWD has not yet been reported in wild reindeer (caribou) in Canada, these studies show that they are at risk of infection. The wild-type reindeer, homozygous for serine at prion protein (PrP) residue 138 (138SS), developed clinical disease upon oral inoculation. Animals carrying at least one asparagine allele (138SN, 138NN) accumulated prions only in the periphery. However, both genotypes were susceptible to intracerebral prion inoculation [2,3]. Fallow deer are wild-type 138NN and are resistant to peripheral but not intracerebral prion infection [4]. Thus, we hypothesize that the138N allele, present in caribou herds in Alberta [5], alters CWD pathogenesis by limiting prion transport from the periphery to the CNS. Our aim is to elucidate the mechanisms involved in this process.

We extracted DNA from ±800 caribou, sequenced the Prnp open reading frame and determined the 138N allele prevalence in Canadian caribou populations. Results show that the 138N allele was highly prevalent in the Chinchaga woodland caribou population in BC (64%). It was also higher in barren-ground (37%) than in other woodland caribou populations (26%). To analyse how the 138N allele affects CWD pathogenesis, we generated knock-in (KI) mice where the mouse PrP is replaced by wild-type 138SS or 138NN cervid PrP. The KIs were obtained by injecting CRISPR/Cas9-edited C57BL6 embryonic stem cells (Bruce4) into wild-type blastocysts, generating chimeras, and breeding progeny to homozygosity in a C57BL6 background. PrP expression was determined using western blotting and qPCR. Correct PrP post-translational modifications were confirmed by PNGase-F and Endo-H digestion. We will inoculate our KIs with CWD-positive material from the corresponding reindeer genotypes [1,2]. The CWD-infected reindeer material was characterized by real-time quaking-induced conversion (RT-QuIC) and its transmissibility to transgenic mice overexpressing elk PrP (TgElk). Attack rate in the TgElks were almost 100%, except for those inoculated with 138SN lymph node material. Western blotting confirmed the presence of proteinase-K resistant PrP in all terminally ill mice. Our goal is to analyse the susceptibility of KIs carrying the 138N allele to intracerebral and peripheral prion infection. We will also assess the efficiency of prion transport from the periphery to the CNS in intraperitoneally inoculated KIs. Prion strain propagation within a host is highly dependent on its PrP genotype. This study will provide insight into how the 138N PrP specifically influences CWD propagation in caribou.

KEYWORDS: Chronic wasting disease; polymorphism; caribou; reindeer; cervid; transgenic mice; knock-in mice

71. Challenging assumptions: an empirical analysis of hunter response to chronic wasting disease in Alberta

John K. Pattison-Williamsa, Lusi Xiea, Vic (W.L.) Adamowicza, Margo Pybusb and Anne Hubbsb

aDepartment of Resource Economics and Environmental Sociology, University of Alberta, Edmonton, Alberta, Canada; bAlberta Environment and Parks, Edmonton, Alberta, Canada

CONTACT John K. Pattison-Williams


Background: Chronic Wasting Disease (CWD) has fundamentally impacted wildlife management in North America. An integral partner in CWD management strategies is the hunting community, whose membership contributes in surveillance, harvest, and policy development. A conventional assumption has been that hunters will avoid or reduce hunting in areas where CWD is identified as high prevalence due to potential human health risks [1], requiring policy incentives to promote continued or increased hunting in these areas. However, this assumption has recently been challenged [2].

Methods: Using mule deer hunter draw information and CWD surveillance data from the Alberta Ministry of Environment and Parks (AEP), we empirically explore the response of mule deer hunters to CWD using license application trends in wildlife management units (WMUs) where CWD has been positively detected. Using a fixed effects (FE) approach, we model the relationship between total resident draw applications and covariates of CWD head counts, quotas, draw success rates between 2005 and 2016 in 39 WMUs.

Results: Our model indicates that mule deer hunters in Alberta are continuing to hunt in WMUs with high CWD prevalence and no significant relationship exists between CWD count and draw applications. These results suggest that (i) hunter decisions regarding license applications are not significantly affected by CWD presence or prevalence, or (ii) hunters perceive CWD in a WMU as a factor that does not detract from, and may be attractive for hunting opportunities.

Conclusions: Our results have important policy implications for CWD management. First, it challenges the assumption that hunters are avoiding CWD zones. Second, it suggests that alternative hunter-based strategies – such as expanded hunting seasons, increased tags or replacement tags – may be more effective and less costly than previously thought to manage the disease. One caveat is that our analysis is based on analyses of aggregate demand for hunting licenses at the WMU level, rather than individual hunter demands over time.

KEYWORDS: Chronic wasting disease; recreational hunting; cervids; alberta; mule deer; wildlife management

75. Mortality surveillance of individuals potentially exposed to chronic wasting disease

Ryan A. Maddoxa, Rachel F. Klosb, Suzanne N. Gibbons-Burgenerb, Bobbi L. Bryanta, Joseph Y. Abramsa, Brian S. Applebyc, Lawrence B. Schonbergera and Ermias D. Belaya

aNational Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA; bWisconsin Department of Health Services, Division of Public Health, Madison, WI, USA; cNational Prion Disease Pathology Surveillance Center (NPDPSC), Case Western Reserve University, Cleveland, OH, USA

CONTACT Ryan A. Maddox


Introduction: Chronic wasting disease (CWD) is a prion disease of cervids. It is unknown whether CWD prions can infect people; if so, transmission would most likely occur through consumption of meat from infected animals. Since 2003, Wisconsin Department of Health Services, Division of Public Health (WDHS) personnel have maintained a database consisting of information collected from hunters who reported eating, or an intention to eat, venison from cervids positive for CWD. This data source makes it possible to evaluate causes of mortality in individuals potentially exposed to CWD.

Methods: The WDHS database contains the name, date of birth, when available, year of CWD-positive deer harvest, and city and state of residence for each potentially exposed individual. The database also includes information on how the deer was processed (self-processed or by a commercial operator) and when applicable, names of others with whom the venison was shared. Duplicate entries (i.e. those who consumed venison from CWD-positive deer in multiple hunt years) are determined by first name, last name, and date of birth. All names in the database are cross-checked with the National Prion Disease Pathology Surveillance Center (NPDPSC) neuropathology database. Vital status of individuals with date of birth available will be tracked through the identification of possible matches in the National Death Index (NDI) and the evaluation of corresponding cause of death codes.

Results: The database consists of 1561 records for hunt years 2003–2017. Of these, 613 records had accompanying date of birth; 14 entries were removed as duplicates, 1 of whom had consumed venison from a CWD-positive deer during three different hunt years, leaving 599 unique individuals for pending submission to NDI. Of these individuals, 265 of 399 (66%) who ate venison from a CWD-positive deer and provided processing information reported self-processing. No matches were found among persons in the database cross-checked with NPDPSC data.

Conclusion: Because of the robust data link between person and CWD-positive animal, reviewing the cause of mortality in potentially exposed persons is possible; those individuals who self-processed and consumed the meat are likely the best source of information about the potential for zoonotic transmission. The expected long incubation period, should transmission to humans occur, necessitates many years of vital status tracking.

76. Prion disease incidence, United States, 2003–2016 

Ryan A. Maddoxa, Marissa K. Persona, Janis E. Blevinsb, Joseph Y. Abramsa, Bobbi L. Bryanta, Brian S. Applebyb, Lawrence B. Schonbergera and Ermias D. Belaya

aNational Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA; bNational Prion Disease Pathology Surveillance Center (NPDPSC), Case Western Reserve University, Cleveland, OH, USA

CONTACT Ryan A. Maddox


Introduction: Mortality data and the results of neuropathological and genetic testing are used to estimate the incidence of prion diseases in the United States.

Methods: Prion disease decedents were identified from restricted-use U.S. national multiple cause-of-death data, via a data use agreement with the National Center for Health Statistics, and from the National Prion Disease Pathology Surveillance Center (NPDPSC) database for 2003–2016. NPDPSC decedents with neuropathological or genetic test results positive for prion disease for whom no likely match was found in the multiple cause-of-death data were added as cases for incidence calculations; those with negative neuropathology results but with cause-of-death data indicating prion disease were removed. Age-adjusted average annual incidence rates for the combined data were calculated using the year 2000 as the standard population.

Results: A total of 5737 decedents were identified as having prion disease during 2003–2016 for an age-adjusted average annual incidence of 1.2 per million populations. The age-adjusted annual incidence ranged from 1.0 per million in 2004 and 2006 to 1.4 per million in 2013; there was an increasing trend in age-adjusted incidence over the entire period (p <0.0001) but no significant increase during the second half (2010–2016, p = 0.08). The age-adjusted incidence between males and females (1.3 and 1.1 per million, respectively) differed significantly (p <0.0001). Twelve cases during 2003–2016 were <30 years of age for an age-specific incidence of 6.9 per billion; only two of these very young cases were sporadic, with the rest being familial (7), variant (2), or iatrogenic (1). The age-specific average annual incidence among those <55 and ≥55 during the time period was 0.2 and 4.7 per million, respectively; incidence among those ≥65 was 5.9 per million.

Conclusion: The incidence of prion diseases, which are invariably fatal, can be estimated through analysis of mortality data supplemented with the results of neuropathological and genetic testing. Incidence in the United States over the last 7 years appears to be relatively stable. Cases <30 years of age continue to be very rare and usually indicate an exogenous source of infection or the presence of a genetic mutation.

77. Assessing chronic wasting disease strain differences in free-ranging cervids across the United States 

Kaitlyn M. Wagnera, Caitlin Ott-Connb, Kelly Strakab, Bob Dittmarc, Jasmine Battend, Robyn Piercea, Mercedes Hennessya, Elizabeth Gordona, Brett Israela, Jenn Ballarde and Mark D Zabela

aPrion Research Center at Colorado State University; bMichigan Department of Natural Resources; cTexas Parks and Wildlife Department; dMissouri Department of Conservation, 5. Arkansas Game and Fish Commission

CONTACT Kaitlyn M. Wagner


Background/Introduction: Chronic wasting disease (CWD) is an invariably fatal prion disease affecting captive and free-ranging cervids, including white-tailed deer, mule deer, moose, elk, and reindeer. Since the initial description of the disease in the 1960’s, CWD has spread to 23 states, 3 Canadian Provinces, South Korea, Norway and, most recently, Finland. While some outbreaks of CWD were caused by transport of infected animals from endemic regions, the origin of CWD in other epizootics is unclear and has not been characterized. Previous studies have shown that there are two distinct strains of CWD. However, the continuous spread and the unclear origin of several outbreaks warrant continued surveillance and further characterization of strain diversity.

Materials and Methods: To address these knowledge gaps, we used biochemical tests to assess strain differences between CWD outbreaks in Michigan, Texas, Missouri, and Colorado, USA. Brain or lymph node samples were homogenized and digested in 50 µg/mL proteinase K (PK). These samples were then run on a Western blot to assess glycoform ratio and electrophoretic mobility. Texas samples were digested in 100 µg/mL PK. To assess conformational stability, brain or lymph node homogenates were incubated in increasing concentrations of guanidine hydrochloride from 0 M to 4 M in 0.5 M increments. Samples were then precipitated in methanol overnight, washed and PK digested in 50 µg/mL PK before slot blotting.

Results: Our results have found significant differences in glycoform ratio between CWD from Michigan and Colorado, but no differences were observed in conformational stability assays. Interestingly, when testing our CWD isolates from Texas to analyse electrophoretic mobility and glycoform ratio, we found that these samples did not exhibit the characteristic band shift when treated with PK, but PK resistant material remained. Additionally, results from our conformational stability assay demonstrate a unique profile of these Texas isolates. Testing of samples from Missouri is currently underway.

Conclusions: Thus far, our data indicate that there are strain differences between CWD circulating in Michigan and CWD in Colorado and provide important insight into CWD strain differences between two non-contiguous outbreaks. We have also identified a unique strain of CWD in Texas with biochemical strain properties not seen in any of our other CWD isolates. These results highlight the importance of continued surveillance to better understand this devastating disease. These results have important implications for CWD emergence, evolution and our understanding of prion strain heterogeneity on the landscape.

105. Differential binding of prions to vegetation 

Elizabeth Triscotta, Alsu Kuznetsovab, Debbie McKenziea and Judd Aikenc

aCentre for Prions and Protein Folding Diseases, Department of Biological Sciences, University of Alberta; bDepartment of Renewable Resources, University of Alberta; cCentre for Prions and Protein Folding Diseases, Department of Agriculture Food and Nutritional Sciences, University of Alberta

CONTACT Elizabeth Triscott


Chronic wasting disease (CWD), a prion disease of cervids, is present in North America and Europe. It affects a variety of captive and free ranging animals, including mule deer, white tailed deer, reindeer, moose, and elk. Preclinical and clinical animals shed infectivity in a number of bodily fluids, including saliva, faeces, and nasal secretions. These prions are resistant to degradation and can contaminate the environment for many years. Factors such as the surface composition of materials and the mineralogy of soils can affect where infectivity accumulates in the environment. Given, however, that in most environments prions will initially contact vegetation, understanding the factors that affect the interaction between prion infectivity and vegetation is of utmost importance. We developed an assay in which infectious brain homogenate is applied to vegetation samples, which are then rinsed. The proteins are precipitated from the rinse water and the amount of PrP that rinses off each vegetation sample was compared. Given that surface composition affects prion adherence, we first compared lichen, which is coated with polysaccharides, and grass, which is covered with a waxy cuticle. Our data indicate that less prions rinse off lichen than grass. Furthermore, the binding of CWD prions to a variety of plants shows that the prion-vegetation interaction is affected by properties of the plant, e.g. microarchitecture and precise chemical composition. Freezing and drying of the plants alters this interaction. These data give us insight in how infectivity moves through the environment and has ramifications for the plausibility of environmental CWD transmission. Understanding where prions accumulate will help in developing methods for environmental monitoring and decontamination.

113. Diagnosis of CWD in a herd of farmed red deer 

Ines Walther, Antanas Staskevicius, Andrei Soutyrine and Gordon Mitchell

National & OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, ON, Canada

CONTACT Gordon Mitchell


Chronic wasting disease (CWD) continues to adversely impact wild and farmed cervids of North America, affecting primarily white-tailed deer (Odocoileus virginianus), mule deer (Odocoileus hemionus), and elk (Cervus canadensis). Red deer (Cervus elaphus) are closely related to elk, and occasional cases of CWD have been reported in farmed red deer in the United States and the Republic of Korea, and in a wild red deer in Norway. CWD was recently detected in farmed red deer for the first time in Canada, in a region geographically distinct from all previous cases of CWD. Understanding the diagnostic features and pathogenesis of CWD in red deer is essential to developing effective disease detection and control strategies in this species. The index case of this herd, a clinically healthy 15-month old male red deer, was initially detected during routine slaughter surveillance testing by ELISA. Confirmatory testing by immunohistochemistry (IHC) demonstrated modest aggregates of pathological prion protein (PrPCWD) in restricted regions of the obex of the medulla and retropharyngeal lymph nodes. Western blot of the obex homogenate revealed a banding pattern consistent with that of other Canadian CWD cases, and distinct from what has been observed in red deer experimentally infected with bovine spongiform encephalopathy. Subsequent disease control measures in this herd resulted in the testing of over 1700 red deer and an additional 10 cases of CWD were identified in females ranging in age from 18 to 28 months. All cases were positive in the obex by ELISA, IHC, and Western blot, although the extent of PrPCWD deposition detected by IHC was somewhat variable. A higher degree of variability in PrPCWD accumulation was found in lymphoid tissues, with PrPCWD not detectable by IHC in the tonsils of several cases. Sequencing of the prion protein gene from all positive cases and a subset of negative cases identified variability at several codons (98, 168, and 226) although the extent to which these polymorphisms may influence susceptibility to infection is not yet evident. Natural transmission of CWD occurs relatively efficiently amongst cervids, facilitating the geographical dissemination of disease to previously naive populations. Determining the unique characteristics of CWD in different cervid species is needed to inform the refinement of disease management approaches.

115. Diversity of chronic wasting disease prion strains 

Camilo Duque Velásqueza, Elizabeth Triscotta, Chiye Kima, Jacques Van der Merwea, Samia Hannaouib, Trent Bollingerc, Christina Carlsond, Sylvie Benestade, Sabine Gilchb, Judd Aikenf and Debbie McKenziea

aDepartment of Biological Sciences, Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada; bDepartment of Ecosystem and Public Health, Calgary Prion Research Unit, University of Calgary, Calgary, Canada; cDepartment of Veterinary Pathology, Canadian Wildlife Health Cooperative, University of Saskatchewan, Saskatoon, Canada; dU.S. Geological Survey-National Wildlife Health Center, Madison, WI, USA; eNorwegian Veterinary Institute, Oslo and Trondheim, Norway; fDepartment of Agricultural, Food and Nutritional Sciences, Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada


Chronic Wasting Disease (CWD) prions affect a variety of cervid species. The expansion of the CWD geographic range and the increasing prevalence makes CWD a concern for wildlife, livestock, and human health. Prion pathogenesis results from the template-directed misfolding of cellular prion proteins (PrPC) into conformational species (e.g. PrPCWD) associated with distinct strains. We propose that cervid cellular prion protein (PrPC) polymorphisms have resulted in prion conformational diversification and speciation (i.e. by adaptive radiation) resulting in emergence of novel CWD strains. New prion strain conformers emerge following transmission between cervids expressing different PrPC amino acid polymorphisms [1-4]. Emergent CWD strains can have novel transmission properties that enable them to infect host species previously considered resistant, suggesting an increase in zoonotic risk as strain-conformers diversify and evolve [2, 3]. We are comparing field CWD isolates of different cervid species from various regions of North America and Norway and have identified differences in biochemical properties of PrPCWD, in vitro and ex vivo propagation and transmission into transgenic mice expressing deer and elk PrP (tgDeer – 96G, tgDeer – 96S, and tgElk-E226) as well as C57Bl6 mice and hamsters. Variations in PrP-res type and protease sensitivity were observed following treatment with proteinase K. Comparison of the PMCA seeding activity using deer and elk PrPC as substrates revealed differences between elk CWD isolates. ElK21 cells also responded differently to various cervid prions. Transmission was efficient for all isolates in tg33 and tgElk mice; however, only a few isolates were able to propagate in host expressing S96 deer PrPC, which has been shown to impose a strong transmission barrier, providing a means of differential selection of CWD strains [2]. Transmission differences were observed following interspecies transmission. While some white-tailed deer and mule deer isolates failed to transmit into hamsters, other isolates transmitted with a low attack rate but considerable sub-clinical infection. These isolates had a migration pattern similar to the hamster-passaged Wisc-1 strain. Two other isolates, transmitted more efficiently into hamsters and produced two different PrP-res migration profiles compared to Wisc-1-like PrP-res. Transmission of Norwegian moose and reindeer CWD isolates is ongoing; preliminary results will be presented. Our data indicate the existence of at least five different CWD strains based on transmission properties.

117. Bank vole bioassay for detection of prion infection in CWD-challenged cynomolgus macaques 

Karla A. Schwenkea, Joo-Hee Waelzleina, Hermann M. Schatzlb, c, Walter Schulz-Schaeffere, Christiane Stahl-Hennigf, Stefanie Czubc, d and Michael Beekesa

aRobert Koch Institute, Prion and Prionoid Research Unit, ZBS 6, Berlin, Germany; bUniversity of Calgary, Calgary Prion Research Unit, Calgary, Canada; cUniversity of Calgary, Faculty of Veterinary Medicine, Calgary, Canada; dCanadian Food Inspection Agency (CFIA), Lethbridge, Canada; eUniversity of Homburg/Saar, Homburg, Germany; f German Primate Center, Goettingen, Germany

CONTACT Karla A. Schwenke


Although Chronic Wasting Disease (CWD) was detected in cervids in the late 1960s, the risk of CWD transmission from cervids to humans is still puzzling. The zoonotic potential which might emanate from CWD was studied by several research groups using a multitude of in vitro and in vivo approaches. These studies provided evidence for a significant transmission barrier for CWD between cervids and humans, but do not allow the definite exclusion of such inter-species transmission. Old- world monkeys such as macaques are currently considered the most reliable animal model for testing the zoonotic potential of CWD prions. Using oral and parenteral transmission routes, our research consortium challenged cynomolgus monkeys with characterized CWD material starting 10 years ago. To test the presence or absence of prion infection in these macaques, we injected bank voles intracerebrally with homogenized brain, spinal cord and spleen tissue from monkeys sacrificed 5–7years after CWD inoculation. Bank voles have been shown to be a universal acceptor for prions derived from various species and were found to be particularly susceptible to infection with CWD prions. Therefore, in our study bank vole bioassays provide a method of choice for the detection of prion infection in the CWD-challenged cynomolgus monkeys. Potential prion disease of macaques will be detected by assessment of prion-specific clinical signs in bank voles. The clinical assessment includes weight monitoring and routine observation of the animals according to a clinical score sheet. Further, CNS and spleen tissue will be examined post mortem for PrPres by Western blot analysis. In case of ambiguous results, we plan to perform second passage inoculations in bank voles. Taken together, these studies are expected to contribute to a definite evaluation of the zoonotic risk of CWD.

120. Detection of CWD prion seeding activity in faeces demonstrates both consistent shedding and potential for environmental monitoring 

Joanne M. Tennanta, Manci Lia, Davin M. Hendersona, Nicholas J. Haleyb, Candace K. Mathiasona and Edward A. Hoovera

aPrion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; bDepartment of Microbiology and Pathology, Midwestern State University, Glendale, AZ, USA

CONTACT Joanne M. Tennant


Background: Chronic wasting disease (CWD) is spreading in susceptible cervid populations in North America, Korea, and Europe. Environmental contamination and exposure to prions is considered to be a significant factor in horizontal CWD transmission. Currently disease surveillance is limited by the necessary presence and testability of infected animals. Previous studies have shown that excreta from CWD infected deer and elk contains prion seeding activity. The detection of CWD through excreta, specifically faeces, could be beneficial in passive monitoring of CWD prevalence in endemic and emerging habitats.

Methods: Longitudinal collections of faeces from low-dose CWD inoculated deer were evaluated by real-time quaking induced conversion (RT-QuIC). To emulate common environmental weathering conditions, CWD-positive faecal samples were dried and exposed to UV light and prion seeding activity was evaluated by RT-QuIC before and after treatment. In addition, faeces from premises known to contain either CWD positive or negative cervids were collected and tested in RT-QuIC for prion seeding activity in a blinded experiment.

Results: CWD prion seeding activity was detected by RT-QuIC in faeces of five out of six low-dose CWD inoculated 96GG deer. The RT-QuIC detectable prion shedding in these deer corresponded with detection of PrPCWD by IHC in rectoanal mucosa-associated lymphoid tissue (RAMALT) biopsy and prion shedding was detected during both the pre-symptomatic and symptomatic stages of disease. Prion seeding activity was little affected by drying and exposure to ultraviolet light as both rectal collected and dried faeces showed prion seeding activity. Faeces collected from the pens containing CWD positive vs. negative deer correlated with presence vs. absence prion seeding activity, respectively.

Conclusion: These studies demonstrate that low-dose inoculated deer shed prion seeding activity in faeces through much of their disease course. Further, the prion seeding activity in faeces was still detectable after exposure to UV light and desiccation. These findings suggest that environmental monitoring of CWD via landscape faecal deposits may be possible as a means for monitoring CWD in populations of free-ranging deer and elk.

124. Longitudinal studies of CWD after low-dose oral exposure in white-tailed deer 

Clare E. Hoover*, Nathaniel D. Denkers, Kristen A. Davenport, Davin M. Henderson, Amy V. Nalls, Erin McNulty, Joanne Tennant, Sarah Cooper, Manci Li, Lauren Bracchi, Candace K. Mathiason and Edward A. Hoover

Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA

CONTACT Edward A. Hoover

*Present address: AstraZeneca, Waltham, NJ


Background: The facile transmission of chronic wasting disease (CWD) in North America, Asia and Europe continues despite exposure to very low concentrations of prions shed by infected cervids in secreta and excreta. Explanations for this enigma could be that excreted prions may have enhanced infectivity and/or that the infectious prion dose is just quite low. Historical studies exploring CWD pathogenesis in deer have used exposures to CWD-positive brain homogenates containing from 0.5 to 10 g of brain – doses much higher than those measured in excreta, and thereby likely to ever occur in nature. We thereby sought to more closely emulate natural exposure context in our current experimental studies.

Methods: To explore how the origin or infectious dose of CWD prions may influence disease transmission or pathogenesis, we orally exposed cohorts of n = 4/group white-tailed deer to low doses of CWD presented as either CWD-positive brain homogenate (containing either 1 mg or 300 ng of brain) or to an amount of pooled saliva from CWD+ donors and containing prion seeding activity (by RT-QuIC) equivalent to 300 ng of CWD+ brain [1]. Inoculated deer were then longitudinally monitored for: (a) onset of prion infection in biopsied tonsil and recto-anal lymphoid tissues by RT-QuIC and immunohistochemistry; (b) prion shedding in saliva and faeces (by RT-QuIC); (c) onset of clinical signs (weekly observation and scoring); and (d) time to clinical disease.

Results: We first detected CWD infection by RT-QuIC seeding activity in tonsil biopsies at 6 or 9 months post exposure, in all inoculation cohorts. Prion shedding in saliva was detected (by RT-QuIC or PMCA-RT-QuIC [2]) concurrent with the first positive tonsil biopsy. Detection of prion seeding activity in faeces was less common overall and its onset observed after positivity in recto-anal lymphoid tissue biopsies. In comparison to historical studies, in which >1,000-fold higher inoculation doses were used, the time to first detection on infection (by tonsil biopsy) was prolonged by ~6 months. However, among the low-dose inoculation cohorts in this study, neither the attack rate, prion shedding profile, nor long-term disease course differed significantly, including the deer exposed to prions of saliva vs. brain origin.

Conclusions: These studies demonstrate that (a) much lower doses of CWD prions that have been used historically for point source exposure studies are sufficient to induce prion infection, shedding, and disease; and (b) although time to first detectable positivity is lengthened, the qualitative aspects of disease pathogenesis thereafter are indistinguishable by inoculum source or exposure magnitude.

Our future studies will aim at establishing the minimum oral infectious dose for CWD in deer and on exploring exposure cofactors.

Supported by NIH R01-NS-061902, P01-AI-077774, F30-ODO-118,143, T32-OD0-10,437

128. Strain profiles of CJD in venison consumers and non-consumers from Alberta and Saskatchewan 

Jennifer Myskiwa,b, Lise Lamourieuxa, Michael Coulthartc, Valerie Simd and Stephanie Bootha,b

aZoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg; bDepartment of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg; cCanadian CJD Surveillance System, Public Health Agency of Canada, Ottawa; dDivision of Neurology, Department of Medicine Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton

CONTACT Jennifer Myskiw


Chronic wasting disease (CWD) is a fatal neurodegenerative disease that is spreading rapidly through wild cervid populations in Alberta and Saskatchewan. The epidemic of CWD in Canada not only has implications for tourism and hunting but it is also a concern over possible zoonotic transmission to humans who eat venison from infected deer. When bovine spongiform encephalopathy (BSE) reached epidemic proportions, variant CJD was identified as an acquired form of BSE due to the unique biochemical fingerprint of the pathologic prion protein (PrP). While the Canadian CJD Surveillance System (CJDSS) is staying vigilant to identify CWD human cases, it is impossible to know what the phenotype of human CWD prions would present with or whether they would be distinct from sporadic CJD cases. Additionally, there is currently no convenient laboratory model to study these differences experimentally. For these reasons we are undertaking a systematic analysis of the molecular diversity of CJD cases in patients who resided in Alberta and Saskatchewan at their time of death. We are comparing CJD profiles of venison consumers and non-consumers using a variety of clinical imaging, pathological and biochemical markers. Firstly, MRIs have been reviewed and neuropathology of over 40 patients for whom CJD was confirmed as the cause of death analysed. In this way we are able to select clinically affected areas for further biochemical analysis of prion protein. We will present data including our analysis to date of levels of protease sensitive and resistant prion protein, temperature and detergent denaturation profiles, and glycoform typing. By combining these methodologies, we intend to extend the baseline CJD typing that is already completed by the CJDSS. Importantly we aim to increase our understanding of the human prion strains that affect the Canadian population. By doing so, we will establish a baseline for the identification of any future atypical CJD cases. For example, those that could arise as a result of exposure to CWD.

130. Evaluation of the sensitivity of different RT-QuIC substrates in detecting and characterizing CWD prions in brains of Norwegian cervids 

Edoardo Bistaffaa, Tram Thu Vuongb, Linh Tranb, Federico Angelo Cazzanigaa, Giulia Salzanoc, Giuseppe Legnamec, Giorgio Giacconea, Sylvie Benestadb and Fabio Modaa

aDivision of Neurology 5 and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy; bNorwegian Veterinary Institute, Oslo, Norway; cLaboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy

CONTACT Tram Thu Vuong


Chronic wasting disease (CWD) is a highly contagious prion pathology affecting captive and free-ranging cervid populations. From its first description 50 years ago, CWD has been detected in United States, Canada, South Korea and, most recently, in Norway. At present, we do not know if these diseases are caused by the same prion strain or whether they spontaneously arose in different countries. CWD spreading among cervids is one of the most important issue for public health due to the ability of this agent to infect a large number of animals and the possible transmission to other animal species, including humans and ovine. Indeed, possible transmission of CWD to ovine that share, in some countries, the same geographic areas of CWD infected animals cannot be excluded. For this reason, it is of fundamental importance to develop a strategy allowing identification of CWD infected samples and verify their ability to propagate within the same or different species. To this aim, we are optimizing RT-QuIC assay coupled with specific biochemical analysis for evaluating whether different CWD samples could produce final reactions products with peculiar differences useful for CWD strain’s identification. RT-QuIC were performed using different substrates of reaction (truncated PrP protein from hamster, reindeer and deer species) for evaluating their sensitivity and specificity in detecting CWD in brains of Norwegian moose, red deer and reindeer. Moreover, through biochemical assessments (PK digestion, guanidine hydrochloride evaluation and use of antibodies against different PrP epitopes), we evaluated whether and to what extent final RT-QuIC products were able to acquire distinct biochemical features according to the strain of CWD. Preliminaryresults showed that deer PrP detected CWD in all species with higher efficiency compared to hamster and reindeer. Notably, truncated deer-PrP was able to rapidly detect positive samples (within 3 h from the beginning of the reaction) compared to the other substrates. Although with less sensitivity, reindeer-PrP identified red deer, reindeer and moose CWD, with this latter being characterized by lower resistance to PK digestion and different PrP banding profile (at Western blot) compared to the others. Therefore, RT-QuIC can be exploited for detecting CWD infected species with high sensitivity and specificity, while biochemical data seem to indicate the possibility of identifying the species of CWD origin. If confirmed, such information will be of fundamental importance for planning actions to contain the spread of the infection (especially to other species, like ovines) in CWD affected regions.


142. Effects of Elk-PrPC expression levels on CWD strain properties 

Camilo Duque Velásqueza, Alicia Oteroa, Chiye Kima, Elizabeth Triscotta, Jeffrey Narayana, Jacques Van der Merweb, Judd Aikenc and Debbie McKenziea

aDepartment of Biological Sciences, Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada; bDepartment of Medicine, Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada; cDepartment of Agricultural, Food and Nutritional Sciences, Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada

CONTACT Alicia Otero


Chronic Wasting Disease (CWD) is a contagious prion disease affecting various species of free-ranging and/or captive cervids on three continents. Species-specific prion protein (PrPC) polymorphisms influence prion conversion into PrPCWD. PrPC amino acid variation can also regulate disease susceptibility to particular prion strains and has been implicated in the diversification of prion strain conformers [1, 2, 3]. Elk and deer PrPC differ at residue E226Q and this amino acid difference has been implicated in the selection of CWD1 and CWD2 prion strains [4]. As PrPC expression has been suggested to affect prion strain evolution [5], we hypothesized that elk PrPC levels affect CWD strain generation. To test this hypothesis, transgenic (tg) FVB mice over-expressing elk PrPC [6] were crossed with prnp knock-out FVB mice to generate tg-elk with different PrPC expression levels. Both tg-elk+/+ and tg-elk± were exposed to white-tailed deer CWD strains (Wisc-1 and H95+) [2, 3]. The H95+ strain was a mixture generated on passage of Wisc-1 in deer heterozygous for H95G96 and Q95S96 [2]. Tg-elk+/+ mice succumbed to Wisc-1 with a mean incubation period of 116 ± 7 days post infection (dpi) compared to 164 ± 11 dpi for the H95+ strain mixture. Consistent with the reduced PrPC expression, the same deer prion strains resulted in longer incubation periods (157 ± 21 dpi and >180 dpi, respectively) when passaged in tg-elk± mice. After first passage, transmission of Wisc-1 and H95+ in tg-elk+/+ mice resulted in a single neuropathological profile that differed from the profile produced by passage of elk prions (described as the CWD2 strain [1]). Our results show that, upon first passage, the E226Q polymorphism did not affect the strain properties of deer prions and indicates a single strain (Wisc-1) was selected by the tg-elk+/+ mice. The comparative analysis of neuropathological profiles between high and low expression tg-elk on first and second passage will be presented.

156. Screening and characterization of unusual sCJD cases in a CWD endemic state in the USA 

Yihui Liua, Manuel Camachoa, Wenquan Zoua,b,c, Qingzhong Konga,b,c

aDepartment of Pathology, Case Western Reserve University (CWRU), Cleveland, USA; bDepartment of Neurology, CWRU, Cleveland, OH, USA; cNational Center for Regenerative Medicine, CWRU, Cleveland, USA

CONTACT Qingzhong Kong


Background: Chronic wasting disease (CWD) has spread to 26 states in the USA and three provinces in Canada, and it has been detected recently in Norway and Finland. Potential CWD zoonosis is a serious public health concern. It is unclear whether CWD transmission to humans has already occurred. We aim to start to address this question by examining all available sCJD cases from a CWD endemic state in the USA.

Methods: Frozen brain tissues from all available sCJD cases archived in the National Prion Disease Pathology Surveillance Center from a US state that has been significantly impacted by CWD were sampled at five brain regions. These brain samples were subjected to detailed biochemical analysis to look for unusual patterns, characteristics, and/or distribution of PrPSc in comparison with sCJD samples from states that have not detected CWD. Unusual cases are further scrutinized for their clinical presentations, histopathological features, and history of cervid hunting and venison consumption.

Results and Conclusions: We have found some unusual sCJD cases in this CWD endemic state. We will report our preliminary findings on their features. Currently there is no convincing evidence to support a direct link to CWD for any of these unusual sCJD cases.

Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the position of the National Prion Disease Pathology Surveillance Center.

175. Environmental pathways of CWD prions 

Alsu Kuznetsovaa, Debbie McKenzieb and Judd M. Aikena

aAgricultural Life and Environmental Sciences Faculty, University of Alberta, Edmonton, Canada; bFaculty of Science, University of Alberta, Edmonton, Canada

CONTACT Alsu Kuznetsov


Soil can serve as a reservoir and route for horizontal transmission of chronic wasting disease (CWD) by interaction with the infectious prion protein (PrPCWD) shed by infected animals. Prion fate in environment is determined by structure of ecosystems including soil and vegetation types. In boreal ecosystems, lichen and shrubs cover sandy textured, quartz-illite soils with surface plant litter horizon. In prairie ecosystems, grassy meadows grow on humus-enriched, loamy or clay montmorillonite soils. Once shed onto the soil surface, prion persistence in the environment primarily depends on the binding and transportation capacity of soils. Factors responsible for prion migration are soil properties such as mineralogical composition, texture, soil organic matter content and pH. We investigated PrPCWD migration in soil profiles by comparing their passage through pure soil minerals and diverse soils using lab-scale soil columns. PrP-res was detected by western blot or protein misfolding cyclic amplification in leachates of columns containing quartz, surface plant litter – soil organic horizon (LFH) of boreal Luvisolic and Brunisolic soils, illite, or the mineral horizons of Luvisol and Brunisol. Infectivity in leachates from quartz, illite and Luvisolic columns was confirmed by bioassay. Analysis of the solid phase of the columns confirmed the migration of PrPCWD to lower layers in the illite, while the PrPCWD in the montmorillonite column remained close to the column surface. While mineralogical composition of soils determines movement of prions, other constituents, such as soil organic matter, microbial population, composition of soil solutions, might affect prion infectivity. To investigate the impact of humic acids (a major component of soil organic material), we incubated CWD agent with humic acids for various lengths of time. Analysis by western blot and bioassay demonstrated that humic acids can reduce PrPres and infectivity over time. Thus, in soils of temperate regions, including the Chernozems of Northern America and Cambisols of Europe, prions would remain at the soil surface due to strong binding to montmorillonite, while in boreal and tundra regions soils (Luvisols, Podzols, and Brunisols), most of the prions would be transported through the plant litter LFH, and partially through the upper soil mineral horizon into lower horizons. Although these soils also have lower levels of humic acids, a soil organic matter compound that has the capacity to reduce CWD infectivity levels, soils of the boreal and tundra regions are less favourable to the horizontal transmission of CWD as these soils make PrPCWD less bioavailable.

199. Chronic wasting disease transmission studies to non-human primates and transgenic mice 

Brent Race, Katie Williams, Christina D. Orrù, Andrew G. Hughson, Lori Lubke and Bruce Chesebro

National Institute of Allergy and Infectious Diseases, Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, Hamilton, MT, USA

CONTACT Brent Race


Introduction: Chronic wasting disease (CWD) is the only prion disease affecting free-ranging animals, reported in North America, South Korea and Norway. Unlike in most other prion disease CWD agents are shed in blood, urine and feces which most likely contribute to the horizontal transmission between cervid species. The developments of amplification-based seeding assays have been instrumental in the detection of low levels of prions in clinical samples. Using real-time quaking-induced conversion (RT-QUIC), we established an ultrasensitive detection method for PrPCWD in the urine from CWD-infected sequentially sampled transgenic mice overexpressing elk prion protein (TgElk mice). In addtion, RT-QUIC was performed in the kidney and brain of theses mice model to trace abnormal prion. Materials and Methods: 44 brain and kidney, urine samples from sequentially collected from CWD-infected TgElk mice (TgElk CWD) were stored at -80℃. In brain and kidney, 10% (w/v) homogenate was prepared in 0.9% sterilized saline. In urine 100uL of each sample was mixed with 10uL 2.8% sodium phosphotungustic acid (NaPTA) and incubated for 1hr at 37℃ with shaking at 1,350 rpm. Samples were centrifuged for 30min at 16,100g. The pellet was resuspended in 10uL of 0.1% SDS/PBS for 30min at 55℃. RT-QUIC reactions were set up in 96-well clear bottom optic plates and consisted of 98uL RT-QUIC buffer [final concentrations of 1XPBS, 1mM EDTA, 10uM Thioflavin, 300mM NaCl buffer and 0.1mg/ml recombinant Syrian hamster recombinant protein (23-231) and 2uL of sample. The RT-QUIC assay was performed on a FLUOstar Omega fluorescence plate reader that was preheated to 42℃ for 60hr with 90sec shaking at 700rpm followed by 1min incubation. Results: Five randomly selected mice were sequentially culled on every 15 days from 30dpi to 120dpi during CWD infected TgElk mice reached terminal stage. Rough hair coats among clinical signs were showed from 90 dpi. PrPCWD in the brain in TgElk CWD was detectable persistently from early stages (30dpi), and in the kidney PrPCWD was also detectable in clinical and terminal stages (90 dpi and 120dpi). PrPCWD in the urine in TgElk CWD reached the highest levels at 120dpi. NaPTA/RT-QUIC was applied to measure PrPCWD in urine samples collected on every 15 days from 30dpi to 120dpi when CWD infected TgElk mice reached terminal stage. PrPCWD in the urine in TgElk CWD reached the highest levels at 90dpi. PrPCWD was also detectable in late and terminal stages (120dpi). Conclusions: We demonstrate that CWD prions can be detected by RT-QUIC or NaPTA/RT-QUIC in the brain, kidney and urine of TgElk mice at the early and terminal stages of disease. Based on these data, we suggest that PrPCWD is excreted into only urine until 90 dpi and then slowly accumulated in kidney. Our results can be used in designing future study of CWD pathogenesis in TgElk mice.

KEYWORDS: Cynomolgus macaques; squirrel monkeys; non-human primate; transgenic mice; CWD; RT-QuIC; prion; cross-species transmission; barrier; chronic wasting disease

214. Identification of novel CWD strains 

Debbie McKenziea, Camilo Duque Velasqueza, Allen Herbsta, Elizabeth Triscotta, Jacques van der Merwea, Samia Hannaouib, Leonardo Corteza, Sara Amidiana, Valerie Sima, Holger Willea, Hermann Schaetzlb, Sabine Gilchb and Judd Aikena

aCentre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada; bCalgary Prion Centre, University of Calgary, Calgary, AB, Canada

CONTACT Debbie McKenzie


Chronic wasting disease is a set of prion diseases infecting captive and wild cervids. As different CWD agents are transmitted between different cervid species and between the same species having different Prnp polymorphisms, novel CWD strains can be generated. These new strains can exhibit different biochemical properties as well as different conformers. Identification of novel CWD strains is critically important as the different strains may vary in their host ranges, increasing the potential for transmission to economically important species as well as zoonotic transmission.

A rate limiting step in the characterization of CWD strains is the identification of deer samples that potentially contain novel strains. Much of the strain generation likely occurs during early passage between different Prnp genotypes (of the same or different species). Traditionally these differences have been identified following passages into rodent models (strains of lab mice, transgenic mice expressing different Prnp sequences and/or hamsters). Incubation periods can be long and the number of potential isolates is high making transmission experiments a slow, tedious, and expensive process. To streamline the process, we have identified a panel of in vitro analyses to help target samples for further characterization. For some isolates, potential new strains have been identified by western blot analysis, others by cervid cell assay, changes in the Prnp sequence, folding and/or aggregation differences as well as ability to seed reactions in RT-QuIC. Isolates of interest are then further characterized by transmission in a variety of different tg mouse lines, wild-type mice, hamsters, and voles. Using these criteria, five potential CWD strains have been identified.

223. Scrapie in white-tailed deer: a strain of the CWD agent that efficiently transmits to sheep? 

Justin J. Greenleea, Robyn D. Kokemullera, S. Jo Moorea and Heather West Greenleeb

aVirus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, IA, USA; bDepartment of Biomedical Sciences, Iowa State University College of Veterinary Medicine, Ames, IA, USA

CONTACT Justin J. Greenlee


Scrapie is a transmissible spongiform encephalopathy of sheep and goats that is associated with widespread accumulation of abnormal prion protein (PrPSc) in the central nervous and lymphoid tissues. Chronic wasting disease (CWD) is the natural prion disease of cervid species, and the tissue distribution of PrPSc in affected cervids is similar to scrapie in sheep. There are several lines of evidence that suggest that multiple strains of CWD exist, which may affect the agent’s potential to transmit to hosts of the same or different species. We inoculated white-tailed deer with the scrapie agent from ARQ/ARQ sheep, which resulted in 100% attack rates by either the intracranial or oronasal route of inoculation. When examining tissues from the brainstems or lymphoid tissues by traditional diagnostic methods such as immunohistochemistry or western blots, it is difficult to differentiate tissues from deer infected with scrapie from those infected with CWD. However, there are several important differences between tissues from scrapie-infected white-tailed deer (WTD scrapie) and those infected with CWD (WTD CWD). First, there are different patterns of PrPSc deposition in the brains of infected deer: brain tissues from deer with WTD scrapie had predominantly particulate and stellate immunoreactivity whereas those from deer with WTD-CWD had large aggregates and plaque-like deposits. Secondly, the incubation periods of WTD scrapie isolates are longer than CWD isolates in mice expressing cervid prion protein. Most notably, the transmission potential of these two isolates back to sheep is distinctly different. Attempts to transmit various CWD isolates to sheep by the oral or oronasal routes have been unsuccessful despite observation periods of up to 7 years. However, WTD scrapie efficiently transmitted back to sheep by the oronasal route. Upon transmission back to sheep, the WTD scrapie isolate exhibited different phenotypic properties when compared to the sheep receiving the original sheep scrapie inoculum including different genotype susceptibilities, distinct PrPSc deposition patterns, and much more rapid incubation periods in transgenic mice expressing the ovine prion protein. The scrapie agent readily transmits between sheep and deer after oronasal exposure. This could confound the identification of CWD strains in deer and the eradication of scrapie from sheep.

234. The European Union Summary Report On Surveillance For The Presence Of Transmissible Spongiform Encephalopathies (TSE): The Situation In 2017 

Angel Ortiz Pelaeza, Valentina Rizzia, Giuseppe Rub, Francesco Ingravalleb and Yves Van der Stedea

aUnit on Biological Hazards and Contaminants, Department of Risk Assessment & Scientific Assistance, European Food Safety Authority (EFSA); bBiostatistics, Epidemiology and Risk Analysis (BEAR) Unit. Istituto Zooprofilattico Sperimentale di Piemonte, Liguria e Valle d ’Aosta, Torino (Italia)

CONTACT Angel Ortiz Pelaez


The European Food Safety Authority publishes a yearly summary of the surveillance activities on transmissible spongiform encephalopathies (TSE) in bovine animals, sheep, goats, cervids, and other species, in the European Union (EU), and in Iceland, Norway and Switzerland. Target groups include: animals clinically suspected of being infected by TSE; animals culled under TSE eradication measures; animals with clinical signs at ante-mortem; emergency slaughtered; fallen stock/not slaughtered for human consumption and healthy slaughtered animals for human consumption, for cervids also hunted and road or predator-injured or killed.

For the first time since bovine spongiform encephalopathy (BSE) had been reported, no cases of classical BSE were reported world-wide in 2017 [1]. Six atypical BSE cases were reported by Spain (1 H /2 L), France (1 H/1 L) and Ireland (1 L), out of the 1,312,714 cattle tested by 28 EU Member States (MS) and 18,526 tested by three non-MS.

In total 431,815 small ruminants were tested in 2017 in the EU. Compared with 2016, there was a 36.2% increase in the number of cases of classical scrapie (CS) in sheep (933), mostly reported by Greece, Spain, Italy and Romania, although over 75% of the cases were sourced in infected flocks. Atypical scrapie (AS) was confirmed in 94 animals. In goats, a decrease of 10% in the number of cases of classical scrapie (567) were reported, 84% in Cyprus. Atypical scrapie was confirmed in nine animals.

Ten-year trend analysis showed a statistically significant decrease in the sheep proportion of CS cases per 10,000 tested animals and an increase in goats. For AS, 10-year data did not detect any statistically significant trend in both species.

After the discovery of chronic wasting disease (CWD) in Norway in 2016, TSE testing in cervids increased in the EU: 10 MS tested 3,585 cervids (75% in Romania, 98.5% from wildlife), all negative. Norway tested 25,736 deer in 2017, leading to the detection of the first case of CWD in a red deer, nine cases in wild reindeer and one in a wild moose. Following EFSA recommendations, the European Commission introduced a 3-year mandatory surveillance programme for six member states starting on 1 January 2018.

By the time of submitting this abstract, CS/AS cases were not yet available, but one new classical BSE case was confirmed in Scotland (2018), one L-type BSE case in Poland (2019) and one case of CWD in a wild moose in Finland in March 2018.

KEYWORDS: BSE; scrapie; CWD; EU; surveillance

244. The use of recreational hunters in Chronic Wasting Disease (CWD) management: behaviour and incentives 

Lusi Xiea, Vic Adamowicza and Patrick Lloyd-Smithb

aUniversity of Alberta; bUniversity of Saskatchewan



Background:While many jurisdictions in North America have implemented some management programmes to address Chronic Wasting Disease (CWD), the disease continues to spread. Although epidemiological models have proposed depopulating infected animals to reduce disease prevalence and spread by increasing hunter harvest (e.g. Potapov et al. 2016) [1], these models do not evaluate the incentives required to increase hunter harvest or the impacts of wildlife disease and management programmes on recreational activity and value. A better understanding of human behavioural responses will help effectively incorporate recreational hunters in wildlife disease control. The objective of this study is to examine the use of incentives to recreational hunters for CWD management by studying hunting trip decisions in response to CWD and its management. We develop an empirical model, with a focus on spatial and temporal substitution patterns of recreational activities, as well as economic benefits of a new recreation season.

Materials and Methods:The data used in this study are from an online survey of recreational hunters in Alberta and Canada. Five thousand hunters were sampled and a response rate of approximately 20% resulted in a usable sample of 707. Hunters were asked to recall hunting trips in 2017 and stated intended visitation with proposed extended hunting seasons for CWD management. We develop a discrete-continuous empirical model that captures hunting trip decisions on sites, periods and frequencies. Explanatory variables included in the model are CWD prevalence levels, policy dummy variables, individuals’ socio-demographic variables as well as travel and time costs. With the estimated parameters, spatial and temporal substitution patterns are captured, measures of the potential harvest of affected deer populations, and economic benefits, are calculated.

Results and Conclusions:We find a negative but insignificant coefficient of CWD which indicates that individuals do not avoid hunting in CWD-infected areas. Individuals are likely to take around six additional trips on average during the extended seasons – this is more than half of the average trips (around 10) they actually took in 2017. We find that individuals are likely to substitute from hunting in areas with lower CWD risks to hunting in the most CWD-infected areas in both seasons. Individuals are better off from an extended season for CWD management. Our findings indicates that it is possible to direct hunting trips for CWD control by extending hunting seasons in CWD-infected areas without additional monetary or non-monetary incentives.

KEYWORDS: Chronic wasting disease; recreation demand

252. RT-QuIC as an antemortem diagnostic tool to detect chronic wasting disease in deer skin 

Natália C. Ferreiraa, Jorge M. Charcob, Michael A. Metricka, Christina D. Orrua, Andrew G. Hughsona, Joaquín Castillaa, Michael W. Millerc and Byron Caugheya

aLaboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA; 2 CIC bioGUNE, Derio (Bizkaia), Spain; 3Colorado Division of Parks and Wildlife, Wildlife Health Program, Fort Collins, Colorado, USA

CONTACT Natália C. Ferreira


Chronic wasting disease (CWD) is a fatal prion disease which affects cervids. This disease has an asymptomatic incubation time of 2–4 years, and during this period they can shed prions through saliva, feces, urine and placental tissue, contaminating the environment. Indeed, CWD highly contagious between cervids and shedding from live, infected animals likely contributes to its rapid spread. So far, CWD has been reported at least in 24 states in the US, as well as Canada, South Korea and Norway. To date, there is no evidence of CWD transmission to humans. However, in infected areas, deer population can drop as much as ~25 percent. Currently, there are two tests approved to diagnose CWD: immunohistochemistry and ELISA. However, these tests are applied postmortem and tissue types approved are the medial retropharyngeal lymph nodes and a specific region of brainstem (obex). Here we describe our efforts to adapt the real time quaking-induced conversion (RT-QuIC) as a diagnostic tool to detect PrPCWD in deer ear skin. Our initial analysis of a blinded panel of 50 samples yielded 82% sensitivity and 75% specificity. We are working to improve the conditions and performance of this assay, given that it might be useful for antemortem CWD diagnostics and surveillance.

123. Detection of prion seeds throughout the eyes of sporadic Creutzfeldt-Jakob disease patients

Christina Orrua, Katrin Soldaub, Christian Cordanoc, Jorge Llibre-Guerrad, Ari J. Greene, Henry Sanchezc, Bradley R. Grovemana, Steven D. Edlandf,g, Jiri G. Safarh,i, Jonathan H. Linb, Byron Caugheya, Michael D. Geschwindc and Christina J. Sigurdsonb,j

aLaboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Hamilton, MT, USA; bDepartment of Pathology, University of California, San Diego, La Jolla, CA USA; cDepartment of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, CA, USA; dCognitive and Behavioral Research Unit, National Institute of Neurology, Havana, Cuba; eDepartment of Neurology, Multiple Sclerosis Center, University of California, San Francisco (UCSF), San Francisco, CA, USA; fDepartments of Family Medicine & Public Health and gNeurosciences, University of California, San Diego, La Jolla, CA USA; hDepartments of Pathology and iNeurology, Case Western Reserve University, Cleveland, OH, USA; jDepartment of Pathology, Immunology, and Microbiology, University of California, Davis, Davis, CA, USA

CONTACT Christina Orru

Orrù and Soldau, mBIO 2018 9:e02095–18. mBio.02095-18


Cases of iatrogenic Creutzfeldt-Jakob disease (CJD) have been reported from corneal transplants, yet the levels of prions in the eye remain unknown. Approximately, 40% of sporadic CJD patients develop visual symptoms and often seek ophthalmological consultation. This study probed the occurrence, level, and distribution of prions in the eyes of patients with sCJD, the most common prion disease in humans. We used the highly sensitive real time quaking-induced conversion (RT-QuIC) assay to measure post-mortem levels of prion seeding activity in cornea, lens, ocular fluid, retina, choroid, sclera, optic nerve, and extraocular muscle. This is the largest series of sCJD patient eyes studied by any assay to date. We detected prion seeding activity in 100% of sCJD eyes representing three common sCJD subtypes with a four log-fold range of seeding activity observed across individuals. The retina consistently showed the highest prion seeding activity. Within the retina, prion deposits were also detected by immunohistochemistry in the outer plexiform layer, and in some eyes the inner plexiform layer. With increased distance from the brain prion seed levels by RT-QuIC declined in eye tissues. Collectively, these results reveal that sCJD patients accumulate prions throughout the eyes, indicating the potential diagnostic utility as well as the possible biohazard.

Chronic Wasting Disease CWD TSE Prion

Cervid to human prion transmission 

Kong, Qingzhong Case Western Reserve University, Cleveland, OH, United States

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. 


here is the latest;


Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice 

Hermann M. Schatzl, Samia Hannaoui, Yo-Ching Cheng, Sabine Gilch (Calgary Prion Research Unit, University of Calgary, Calgary, Canada) Michael Beekes (RKI Berlin), Walter Schulz-Schaeffer (University of Homburg/Saar, Germany), Christiane Stahl-Hennig (German Primate Center) & Stefanie Czub (CFIA Lethbridge). 

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 detected in spinal cord and brain of some 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 pre-clinical 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.. 

***> 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. <***


P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging 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.. 

SEEMS THAT THEY FOUND Highly endemic states had a higher rate of prion disease mortality compared to non-CWD 


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.. 

IN THIS STUDY, THERE WERE autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017, 


included 104 patients. SEEMS THEY FOUND THAT The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%), 


THAT The Majority of cases were male (60%), AND half of them had exposure to wild game. 


see more on Prion 2017 Macaque study from Prion 2017 Conference and other updated science on cwd tse prion zoonosis below...terry

Sunday, February 25, 2018 



Cervid to human prion transmission 5R01NS088604-04 Update

snip...full text;


Experts: Yes, chronic wasting disease in deer is a public health issue — for people

*** The potential impact of prion diseases on human health was greatly magnified by the recognition that interspecies transfer of BSE to humans by beef ingestion resulted in vCJD. While changes in animal feed constituents and slaughter practices appear to have curtailed vCJD, there is concern that CWD of free-ranging deer and elk in the U.S. might also cross the species barrier. Thus, consuming venison could be a source of human prion disease. Whether BSE and CWD represent interspecies scrapie transfer or are newly arisen prion diseases is unknown. Therefore, the possibility of transmission of prion disease through other food animals cannot be ruled out. There is evidence that vCJD can be transmitted through blood transfusion. There is likely a pool of unknown size of asymptomatic individuals infected with vCJD, and there may be asymptomatic individuals infected with the CWD equivalent. These circumstances represent a potential threat to blood, blood products, and plasma supplies. 

you can see more evidence here ;

Wednesday, May 24, 2017 

PRION2017 CONFERENCE VIDEO UPDATE 23 – 26 May 2017 Edinburgh UPDATE 1

Thursday, December 1, 2016 




PRION 2010

International Prion Congress: From agent to disease September 8–11, 2010 Salzburg, Austria

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.


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. 

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”


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


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


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.


*** 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. 

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 


*** 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).*** 


“Wow,” he said. “Unlike anything we've seen before.”

The prions from the Texas deer were a lot harder to destroy than the ones from the Colorado elk. In fact, the guanidine barely damaged them at all. “We’ve never seen that before in any prion strain, which means that it has a completely different structure than we've ever seen before,” says Zabel. And that suggests that it might be a very different kind of chronic wasting disease. The researchers ran the same test on another Texas deer, with the same results.

One day in late February, in their laboratory in Fort Collins, Colorado, Wagner and Zabel compared the prions from the brains of CWD-infected deer in Texas with those of elk in Colorado. They want to know if the proteins were all mangled in the same way, or not. “If they are different, this would suggest that we have different strain properties, which is evidence as we're building our case that we might have multiple strains of CWD circulating in the U.S.,” says Wagner.

Step one is to see if they’re equally easy to destroy using a chemical called guanidine. The shape of a prion dictates everything, including the way it interacts with an animal’s cells and the ease with which chemicals can unfold it.

“Moment of truth,” said Wagner, as she and Zabel huddled around a computer, waiting for results to come through. When they did, Zabel was surprised.

“Wow,” he said. “Unlike anything we've seen before.”

The prions from the Texas deer were a lot harder to destroy than the ones from the Colorado elk. In fact, the guanidine barely damaged them at all. “We’ve never seen that before in any prion strain, which means that it has a completely different structure than we've ever seen before,” says Zabel. And that suggests that it might be a very different kind of chronic wasting disease. The researchers ran the same test on another Texas deer, with the same results.

Now, these are only the preliminary results from a few animals. Wagner and Zabel have a lot more experiments to do. But if future tests come to the same conclusion, it would support their hypothesis that there are multiple strains of chronic wasting disease out there, all with different origins. That, in turn, could mean that this disease will become even trickier to manage than it already is.

And, Zabel adds, there’s something else. “If it's still evolving, it may still evolve into a form that could potentially, eventually affect humans,” he says.

Zabel is not the only one worried about that possibility. 

 OSTERHOLM, THE EPIDEMIOLOGIST from Minnesota, is also concerned. He directs the Center for Infectious Disease Research and Policy at the University of Minnesota, and is serving a one-year stint as a “Science Envoy for Health Security” with the U.S. State Department. In February, he told Minnesota lawmakers that when it comes to chronic wasting disease, we are playing with fire. “You are going to hear from people that this is not going to be a problem other than a game farm issue. You're going to hear from people that it's not going to transmit to people, and I hope they're right, but I wouldn't bet on it,” he said. “And if we lose this one and haven’t done all we can do, we will pay a price.”

If that wasn’t warning enough, he added: “Just remember what happened in England.”

SUNDAY, APRIL 14, 2019 

Chronic Wasting Disease TSE Prion Strains everything in Texas is bigger, better, and badder

WEDNESDAY, MAY 15, 2019 

TAHC CWD TSE Prion Summary Minutes of the 402nd Commission Meeting – 12/11/2018

FRIDAY, APRIL 05, 2019 

TPWD CWD Sampling Effort Leads to Proposed Containment Zone Expansion

TUESDAY, MARCH 05, 2019 

TAHC CWD TSE PRION AT 144 POSITIVE MINUTES OF THE 401st COMMISSION MEETING Texas Animal Health Commission August 7, 2018 



SUNDAY, JUNE 10, 2018 



TEXAS TAHC CWD TSE PRION Trace Herds INs and OUTs Summary Minutes of the 399th and 398th Commission Meeting – 8/22/2017 5/9/2017

TEXAS BREEDER DEER ESCAPEE WITH CWD IN THE WILD, or so the genetics would show?

OH NO, please tell me i heard this wrong, a potential Texas captive escapee with cwd in the wild, in an area with positive captive cwd herd?

apparently, no ID though. tell me it ain't so please...

23:00 minute mark

''Free Ranging Deer, Dr. Deyoung looked at Genetics of this free ranging deer and what he found was, that the genetics on this deer were more similar to captive deer, than the free ranging population, but he did not see a significant connection to any one captive facility that he analyzed, so we believe, Ahhhhhh, this animal had some captive ahhh, whatnot.''

Wyoming CWD Dr. Mary Wood

''first step is admitting you have a problem''

''Wyoming was behind the curve''

wyoming has a problem...

the other part, these tissues and things in the body then shed or secrete prions which then are the route to other animals into the environment, so in particular, the things, the secretions that are infectious are salvia, feces, blood and urine. so pretty much anything that comes out of a deer is going to be infectious and potential for transmitting disease.
Texas Chronic Wasting Disease CWD TSE Prion Symposium 2018 posted January 2019 VIDEO SET 18 CLIPS See Wisconsin update...terrible news, right after Texas updated map around 5 minute mark...
cwd update on Wisconsin from Tammy Ryan...
Wyoming CWD Dr. Mary Wood ''first step is admitting you have a problem'' ''Wyoming was behind the curve'' wyoming has a problem...


Texas Chronic Wasting Disease CWD TSE Prion Symposium 2018 posted January 2019 VIDEO SET 18 CLIPS 



A. Scrapie: The first positive scrapie case in Texas since 2008 was identified in the Panhandle in April 2016 and the flock and premises remains under quarantine.

Chronic Wasting Disease – NOT Approved – denied waiver to allow twin moose calves to enter Texas from a non-CWD monitored herd. According to Texas Administrative Code Title 4, Part 2, Chapter 51.10 all CWD susceptible species must meet federal requirements for interstate movements. Additionally, observation of an animal does not provide sufficient evidence of disease freedom, especially when applied to CWD.


A. Chronic Wasting Disease (CWD) in white-tailed deer (WTD): There are 5 positive WTD breeding facilities in Texas. The total number of positive WTD and current status of each facility is listed below:

Facility Current Status Number Positive

1 Depopulated in 2015 4

2 Depopulated in early 2016 5

3 Quarantined January 2016, managed on herd plan 28, 12 suspects, 2 elk

4 Quarantined March 2016, recently depopulated ~100 does and managed on a herd plan, 25

5 Quarantined May 2017, depopulated herd October 2017 2

In late FY 2017, USDA informed TAHC that some end of year CWD indemnity funds were designated to Texas for the current positive herds. USDA required complete depopulation of the newest facility (Facility #5) based on the smaller size. The herd was depopulated in October and one additional positive doe was disclosed. The remaining available funds were allocated to use on facility 4 to remove deer in high risk pens. Of the 100 deer depopulated in facility #4, 9 were positive and all 9 were in pens in the same section as the index pen. In addition, a hunter harvested buck at facility #4 was positive that was harvested in November 2017.

In facility #3, since January 2016, there are a total of 28 positives and 12 suspects (tonsil biopsy confirmed positive only at this time) WTD. Of those, 31 are from the breeder pens or grower pens (17 bucks and 14 does). In addition, there were 9 positives disclosed from hunter harvested samples from 4 different pastures (6 bucks, 3 does). And there were 2 positive elk cows disclosed from 117 samples in 1 pasture. Both cows were natural additions to the elk herd.

The free ranging summary for the 2017-2018 hunting season include 2 positive mule deer from Hudspeth County, 2 mule deer from Hartley County, and 1 WTD from Hartley County. The WTD was on the Containment Zone border and a slight adjustment to that zone will be addressed before the next hunting season.


Summary Minutes of the 400th Commission Meeting – 4/17/2018


Statewide exotic CWD susceptible species surveillance monitoring in ongoing. General surveillance includes any facility that is testing CWD susceptible species for their annual premise requirement. Hunter harvest samples include samples collected at check stations in one of the 3 zones (the Panhandle, West Texas, or Medina area). Samples collected on positive premises include testing to meet requirements for a positive premise herd plan.

CWD Susceptible Species Surveillance 2017-18

Exotic Species General Statewide Surveillance Positive PremiseContainment Zone* Hunter Harvest in Zones for ’17-18

Positive Negative Positive Negative Positive Negative

Red Deer 0 70 0 14 0 8

Elk 0 30 2 (cows) 115 0 19

Sika 26 0 1 0 4

Total 0 126 2 130 0 31 



*** Hartley County Sheep with Scrapie, and CWD in Hartley county ??? 

*** Friday, April 22, 2016 

*** Texas Scrapie Confirmed in a Hartley County Sheep where CWD was detected in a Mule Deer 


SUNDAY, MAY 14, 2017 

85th Legislative Session 2017 AND THE TEXAS TWO STEP Chronic Wasting Disease CWD TSE Prion, and paying to play

Wednesday, May 04, 2016 

TPWD proposes the repeal of §§65.90 -65.94 and new §§65.90 -65.99 Concerning Chronic Wasting Disease - Movement of Deer Singeltary Comment Submission 


Texas 84th Legislature 2015 H.R. No. 2597 Kuempel Deer Breeding Industry TAHC TPWD CWD TSE PRION 


TEXAS 84th Legislature commencing this January, deer breeders are expected to advocate for bills that will seek to further deregulate their industry

TEXAS HISTORY OF CWD Singeltary telling TAHC, that CWD was waltzing into Texas from WSMR around Trans Pecos region, starting around 2001, 2002, and every year, there after, until New Mexico finally shamed TAHC et al to test where i had been telling them to test for a decade. 2012 cwd was detected first right there where i had been trying to tell TAHC for 10 years. 

***> Singeltary on Texas Chronic Wasting Disease CWD TSE Prion History <***

FRIDAY, MAY 10, 2019 

Wisconsin Portage County Deer Farm Depopulated due to CWD TSE Prion ​6 Cases Confirmed

THURSDAY, MAY 09, 2019 

Minnesota Seven deer test positive for CWD at Crow Wing County deer farm

THURSDAY, MAY 23, 2019 

Michigan Osceola County deer farm/ranch owner arraigned on several violations

THURSDAY, MAY 09, 2019 

Michigan CWD TSE Prion increases to 120 Cases to Date


Michigan CWD Identified in a Montcalm County Farmed Deer


Oklahoma Farmed Elk Lincoln County has tested positive for chronic wasting disease CWD TSE Prion 


Chronic Wasting Disease Confirmed in One Farmed Oklahoma Elk 


South Dakota Chronic wasting disease (CWD) has been identified in a captive elk in Clark County


North Dakota Deer Found Near Williston Tests Positive for CWD


Missouri MDC reports 41 new positive test results for CWD have been confirmed following its sampling

TUESDAY, APRIL 23, 2019 

Virginia DGIF CWD TSE Prion As April 2019 the Department has diagnosed 68 positive cases since 2009 


Montana Chronic Wasting Disease CWD TSE Prion 2018 Report 26 New Cases

Tennessee officials concerned after 183 deer test positive for CWD TSE Prion
FRIDAY, MAY 10, 2019 

Alabama Officially Invites CWD TSE Prion Into Their State When Bait Bill Becomes Law


Estimating the amount of Chronic Wasting Disease infectivity passing through abattoirs and field slaughter


CWD, TSE, PRION, MATERNAL mother to offspring, testes, epididymis, seminal fluid, and blood


USDA APHIS CDC Cervids: Chronic Wasting Disease Specifics Updated 2019


Chronic Wasting Disease CWD TSE Prion United States of America Update March 16, 2019


USDA ARS 2018 USAHA RESOLUTIONS Investigation of the Role of the Prion Protein Gene in CWD Resistance and Transmission of Disease

TUESDAY, APRIL 30, 2019 

Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies 2018 Annual Report

FRIDAY, MARCH 29, 2019

First Detection of Chronic Wasting Disease in a Wild Red Deer (Cervus elaphus) in Europe

let's review some recent science on the environmental effects of the exposure of the cwd tse prion, it's not pretty...

P-147 Infection and detection of PrPCWD in soil from CWD infected farm in Korea

Hyun Joo Sohn, Kyung Je Park, In Soon Roh, Hyo Jin Kim, Hoo Chang Park, Byounghan Kim

Animal and Plant Quarantine Agency (QIA), Korea

Transmissible spongiform encephalopathy (TSE) is a fatal neurodegenerative disorder, which is so-called as prion diseases due to the causative agents (PrPSc). TSEs are believed to be due to the template-directed accumulation of disease-associated prion protein, generally designated PrPSc. Chronic wasting disease (CWD) is the prion disease that is known spread horizontally. CWD has confirmed last in Republic of Korea in 2010 since first outbreak of CWD in 2001. The environmental reservoirs mediate the transmission of this disease. The significant levels of infectivity have been detected in the saliva, urine, and feces of TSE-infected animals. Using serial protein misfolding cyclic amplification (sPMCA), we developed a detection method for CWD PrPSc in soil from CWD affected farm in 2010. We found to detect PrPSc in soil from CWD infected farm, but not detect PrPSc in soil of wild cervid habitats and normal cervid farm in Korea. We also tried the bioassay on transgenic mice overexpressing elk prion protein (TgElk mice) to confirm infectivity of CWD-infected farm soil and washing solution of it. As the results, there was the presence of infectious prions in them. The attack rates were each 12.5% (1/8, soil) and 100% (6/6, soil washing solution). Our method appears to be a very useful technique for monitoring PrPSc levels in environmental conditions. 

see full text;

2018 - 2019

***> This is very likely to have parallels with control efforts for CWD in cervids.

Rapid recontamination of a farm building occurs after attempted prion removal

Kevin Christopher Gough, BSc (Hons), PhD1, Claire Alison Baker, BSc (Hons)2, Steve Hawkins, MIBiol3, Hugh Simmons, BVSc, MRCVS, MBA, MA3, Timm Konold, DrMedVet, PhD, MRCVS3 and Ben Charles Maddison, BSc (Hons), PhD2


The transmissible spongiform encephalopathy scrapie of sheep/goats and chronic wasting disease of cervids are associated with environmental reservoirs of infectivity. 

Preventing environmental prions acting as a source of infectivity to healthy animals is of major concern to farms that have had outbreaks of scrapie and also to the health management of wild and farmed cervids. 

Here, an efficient scrapie decontamination protocol was applied to a farm with high levels of environmental contamination with the scrapie agent. 

Post-decontamination, no prion material was detected within samples taken from the farm buildings as determined using a sensitive in vitro replication assay (sPMCA). 

A bioassay consisting of 25 newborn lambs of highly susceptible prion protein genotype VRQ/VRQ introduced into this decontaminated barn was carried out in addition to sampling and analysis of dust samples that were collected during the bioassay. 

Twenty-four of the animals examined by immunohistochemical analysis of lymphatic tissues were scrapie-positive during the bioassay, samples of dust collected within the barn were positive by month 3. 

The data illustrates the difficulty in decontaminating farm buildings from scrapie, and demonstrates the likely contribution of farm dust to the recontamination of these environments to levels that are capable of causing disease.


As in the authors' previous study,12 the decontamination of this sheep barn was not effective at removing scrapie infectivity, and despite the extra measures brought into this study (more effective chemical treatment and removal of sources of dust) the overall rates of disease transmission mirror previous results on this farm. With such apparently effective decontamination (assuming that at least some sPMCA seeding ability is coincident with infectivity), how was infectivity able to persist within the environment and where does infectivity reside? Dust samples were collected in both the bioassay barn and also a barn subject to the same decontamination regime within the same farm (but remaining unoccupied). Within both of these barns dust had accumulated for three months that was able to seed sPMCA, indicating the accumulation of scrapie-containing material that was independent of the presence of sheep that may have been incubating and possibly shedding low amounts of infectivity.

This study clearly demonstrates the difficulty in removing scrapie infectivity from the farm environment. Practical and effective prion decontamination methods are still urgently required for decontamination of scrapie infectivity from farms that have had cases of scrapie and this is particularly relevant for scrapiepositive goatherds, which currently have limited genetic resistance to scrapie within commercial breeds.24 This is very likely to have parallels with control efforts for CWD in cervids.

Acknowledgements The authors thank the APHA farm staff, Tony Duarte, Olly Roberts and Margaret Newlands for preparation of the sheep pens and animal husbandry during the study. The authors also thank the APHA pathology team for RAMALT and postmortem examination.

Funding This study was funded by DEFRA within project SE1865. 

Competing interests None declared. 

Saturday, January 5, 2019 

Rapid recontamination of a farm building occurs after attempted prion removal 


BSE infectivity survives burial for five years with only limited spread


P69 Experimental transmission of CWD from white-tailed deer to co-housed reindeer 

Mitchell G (1), Walther I (1), Staskevicius A (1), Soutyrine A (1), Balachandran A (1) 

(1) National & OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada. 

Chronic wasting disease (CWD) continues to be detected in wild and farmed cervid populations of North America, affecting predominantly white-tailed deer, mule deer and elk. Extensive herds of wild caribou exist in northern regions of Canada, although surveillance has not detected the presence of CWD in this population. Oral experimental transmission has demonstrated that reindeer, a species closely related to caribou, are susceptible to CWD. Recently, CWD was detected for the first time in Europe, in wild Norwegian reindeer, advancing the possibility that caribou in North America could also become infected. Given the potential overlap in habitat between wild CWD-infected cervids and wild caribou herds in Canada, we sought to investigate the horizontal transmissibility of CWD from white-tailed deer to reindeer. 

Two white-tailed deer were orally inoculated with a brain homogenate prepared from a farmed Canadian white-tailed deer previously diagnosed with CWD. Two reindeer, with no history of exposure to CWD, were housed in the same enclosure as the white-tailed deer, 3.5 months after the deer were orally inoculated. The white-tailed deer developed clinical signs consistent with CWD beginning at 15.2 and 21 months post-inoculation (mpi), and were euthanized at 18.7 and 23.1 mpi, respectively. Confirmatory testing by immunohistochemistry (IHC) and western blot demonstrated widespread aggregates of pathological prion protein (PrPCWD) in the central nervous system and lymphoid tissues of both inoculated white-tailed deer. Both reindeer were subjected to recto-anal mucosal associated lymphoid tissue (RAMALT) biopsy at 20 months post-exposure (mpe) to the white-tailed deer. The biopsy from one reindeer contained PrPCWD confirmed by IHC. This reindeer displayed only subtle clinical evidence of disease prior to a rapid decline in condition requiring euthanasia at 22.5 mpe. Analysis of tissues from this reindeer by IHC revealed widespread PrPCWD deposition, predominantly in central nervous system and lymphoreticular tissues. Western blot molecular profiles were similar between both orally inoculated white-tailed deer and the CWD positive reindeer. Despite sharing the same enclosure, the other reindeer was RAMALT negative at 20 mpe, and PrPCWD was not detected in brainstem and lymphoid tissues following necropsy at 35 mpe. Sequencing of the prion protein gene from both reindeer revealed differences at several codons, which may have influenced susceptibility to infection. 

Natural transmission of CWD occurs relatively efficiently amongst cervids, supporting the expanding geographic distribution of disease and the potential for transmission to previously naive populations. The efficient horizontal transmission of CWD from white-tailed deer to reindeer observed here highlights the potential for reindeer to become infected if exposed to other cervids or environments infected with CWD. 

***> Infectious agent of sheep scrapie may persist in the environment for at least 16 years

***> Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded. 

Gudmundur Georgsson,1 Sigurdur Sigurdarson2 and Paul Brown3


Gudmundur Georgsson

1 Institute for Experimental Pathology, University of Iceland, Keldur v/vesturlandsveg, IS-112 Reykjavı´k, Iceland

2 Laboratory of the Chief Veterinary Officer, Keldur, Iceland

3 Bethesda, Maryland, USA

Received 7 March 2006 Accepted 6 August 2006

In 1978, a rigorous programme was implemented to stop the spread of, and subsequently eradicate, sheep scrapie in Iceland. Affected flocks were culled, premises were disinfected and, after 2–3 years, restocked with lambs from scrapie-free areas. Between 1978 and 2004, scrapie recurred on 33 farms. Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded. Of special interest was one farm with a small, completely self-contained flock where scrapie recurred 18 years after culling, 2 years after some lambs had been housed in an old sheephouse that had never been disinfected. Epidemiological investigation established with near certitude that the disease had not been introduced from the outside and it is concluded that the agent may have persisted in the old sheep-house for at least 16 years.






Back around 2000, 2001, or so, I was corresponding with officials abroad during the bse inquiry, passing info back and forth, and some officials from here inside USDA aphis FSIS et al. In fact helped me get into the USA 50 state emergency BSE conference call way back. That one was a doozy. But I always remember what “deep throat” I never knew who they were, but I never forgot;

Some unofficial information from a source on the inside looking out -


As early as 1992-3 there had been long studies conducted on small pastures containing scrapie infected sheep at the sheep research station associated with the Neuropathogenesis Unit in Edinburgh, Scotland. Whether these are documented...I don't know. But personal recounts both heard and recorded in a daily journal indicate that leaving the pastures free and replacing the topsoil completely at least 2 feet of thickness each year for SEVEN years....and then when very clean (proven scrapie free) sheep were placed on these small pastures.... the new sheep also broke out with scrapie and passed it to offspring. I am not sure that TSE contaminated ground could ever be free of the agent!! A very frightening revelation!!!

---end personal email---end...tss

Infectivity surviving ashing to 600*C is (in my opinion) degradable but infective. based on Bown & Gajdusek, (1991), landfill and burial may be assumed to have a reduction factor of 98% (i.e. a factor of 50) over 3 years. CJD-infected brain-tissue remained infectious after storing at room-temperature for 22 months (Tateishi et al, 1988). Scrapie agent is known to remain viable after at least 30 months of desiccation (Wilson et al, 1950). and pastures that had been grazed by scrapie-infected sheep still appeared to be contaminated with scrapie agent three years after they were last occupied by sheep (Palsson, 1979).

Dr. Paul Brown Scrapie Soil Test BSE Inquiry Document

Using in vitro Prion replication for high sensitive detection of prions and prionlike proteins and for understanding mechanisms of transmission. 

Claudio Soto Mitchell Center for Alzheimer's diseases and related Brain disorders, Department of Neurology, University of Texas Medical School at Houston. 

Prion and prion-like proteins are misfolded protein aggregates with the ability to selfpropagate to spread disease between cells, organs and in some cases across individuals. I n T r a n s m i s s i b l e s p o n g i f o r m encephalopathies (TSEs), prions are mostly composed by a misfolded form of the prion protein (PrPSc), which propagates by transmitting its misfolding to the normal prion protein (PrPC). The availability of a procedure to replicate prions in the laboratory may be important to study the mechanism of prion and prion-like spreading and to develop high sensitive detection of small quantities of misfolded proteins in biological fluids, tissues and environmental samples. Protein Misfolding Cyclic Amplification (PMCA) is a simple, fast and efficient methodology to mimic prion replication in the test tube. PMCA is a platform technology that may enable amplification of any prion-like misfolded protein aggregating through a seeding/nucleation process. In TSEs, PMCA is able to detect the equivalent of one single molecule of infectious PrPSc and propagate prions that maintain high infectivity, strain properties and species specificity. Using PMCA we have been able to detect PrPSc in blood and urine of experimentally infected animals and humans affected by vCJD with high sensitivity and specificity. Recently, we have expanded the principles of PMCA to amplify amyloid-beta (Aβ) and alphasynuclein (α-syn) aggregates implicated in Alzheimer's and Parkinson's diseases, respectively. Experiments are ongoing to study the utility of this technology to detect Aβ and α-syn aggregates in samples of CSF and blood from patients affected by these diseases.


***>>> Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prioncontaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.


Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis. 

New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication 

Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production 

Detection of protease-resistant cervid prion protein in water from a CWD-endemic area 

A Quantitative Assessment of the Amount of Prion Diverted to Category 1 Materials and Wastewater During Processing 

Rapid assessment of bovine spongiform encephalopathy prion inactivation by heat treatment in yellow grease produced in the industrial manufacturing process of meat and bone meals 


Survival and Limited Spread of TSE Infectivity after Burial 

Discussion Classical scrapie is an environmentally transmissible disease because it has been reported in naïve, supposedly previously unexposed sheep placed in pastures formerly occupied by scrapie-infected sheep (4, 19, 20). 

Although the vector for disease transmission is not known, soil is likely to be an important reservoir for prions (2) where – based on studies in rodents – prions can adhere to minerals as a biologically active form (21) and remain infectious for more than 2 years (22). 

Similarly, chronic wasting disease (CWD) has re-occurred in mule deer housed in paddocks used by infected deer 2 years earlier, which was assumed to be through foraging and soil consumption (23). 

Our study suggested that the risk of acquiring scrapie infection was greater through exposure to contaminated wooden, plastic, and metal surfaces via water or food troughs, fencing, and hurdles than through grazing. 

Drinking from a water trough used by the scrapie flock was sufficient to cause infection in sheep in a clean building. 

Exposure to fences and other objects used for rubbing also led to infection, which supported the hypothesis that skin may be a vector for disease transmission (9). 

The risk of these objects to cause infection was further demonstrated when 87% of 23 sheep presented with PrPSc in lymphoid tissue after grazing on one of the paddocks, which contained metal hurdles, a metal lamb creep and a water trough in contact with the scrapie flock up to 8 weeks earlier, whereas no infection had been demonstrated previously in sheep grazing on this paddock, when equipped with new fencing and field furniture. 

When the contaminated furniture and fencing were removed, the infection rate dropped significantly to 8% of 12 sheep, with soil of the paddock as the most likely source of infection caused by shedding of prions from the scrapie-infected sheep in this paddock up to a week earlier. 

This study also indicated that the level of contamination of field furniture sufficient to cause infection was dependent on two factors: stage of incubation period and time of last use by scrapie-infected sheep. 

Drinking from a water trough that had been used by scrapie sheep in the predominantly pre-clinical phase did not appear to cause infection, whereas infection was shown in sheep drinking from the water trough used by scrapie sheep in the later stage of the disease. 

It is possible that contamination occurred through shedding of prions in saliva, which may have contaminated the surface of the water trough and subsequently the water when it was refilled. 

Contamination appeared to be sufficient to cause infection only if the trough was in contact with sheep that included clinical cases. 

Indeed, there is an increased risk of bodily fluid infectivity with disease progression in scrapie (24) and CWD (25) based on PrPSc detection by sPMCA. 

Although ultraviolet light and heat under natural conditions do not inactivate prions (26), furniture in contact with the scrapie flock, which was assumed to be sufficiently contaminated to cause infection, did not act as vector for disease if not used for 18 months, which suggest that the weathering process alone was sufficient to inactivate prions. 

PrPSc detection by sPMCA is increasingly used as a surrogate for infectivity measurements by bioassay in sheep or mice. 

In this reported study, however, the levels of PrPSc present in the environment were below the limit of detection of the sPMCA method, yet were still sufficient to cause infection of in-contact animals. 

In the present study, the outdoor objects were removed from the infected flock 8 weeks prior to sampling and were positive by sPMCA at very low levels (2 out of 37 reactions). 

As this sPMCA assay also yielded 2 positive reactions out of 139 in samples from the scrapie-free farm, the sPMCA assay could not detect PrPSc on any of the objects above the background of the assay. 

False positive reactions with sPMCA at a low frequency associated with de novo formation of infectious prions have been reported (27, 28). 

This is in contrast to our previous study where we demonstrated that outdoor objects that had been in contact with the scrapie-infected flock up to 20 days prior to sampling harbored PrPSc that was detectable by sPMCA analysis [4 out of 15 reactions (12)] and was significantly more positive by the assay compared to analogous samples from the scrapie-free farm. 

This discrepancy could be due to the use of a different sPMCA substrate between the studies that may alter the efficiency of amplification of the environmental PrPSc. 

In addition, the present study had a longer timeframe between the objects being in contact with the infected flock and sampling, which may affect the levels of extractable PrPSc. 

Alternatively, there may be potentially patchy contamination of this furniture with PrPSc, which may have been missed by swabbing. 

The failure of sPMCA to detect CWD-associated PrP in saliva from clinically affected deer despite confirmation of infectivity in saliva-inoculated transgenic mice was associated with as yet unidentified inhibitors in saliva (29), and it is possible that the sensitivity of sPMCA is affected by other substances in the tested material. 

In addition, sampling of amplifiable PrPSc and subsequent detection by sPMCA may be more difficult from furniture exposed to weather, which is supported by the observation that PrPSc was detected by sPMCA more frequently in indoor than outdoor furniture (12). 

A recent experimental study has demonstrated that repeated cycles of drying and wetting of prion-contaminated soil, equivalent to what is expected under natural weathering conditions, could reduce PMCA amplification efficiency and extend the incubation period in hamsters inoculated with soil samples (30). 

This seems to apply also to this study even though the reduction in infectivity was more dramatic in the sPMCA assays than in the sheep model. 

Sheep were not kept until clinical end-point, which would have enabled us to compare incubation periods, but the lack of infection in sheep exposed to furniture that had not been in contact with scrapie sheep for a longer time period supports the hypothesis that prion degradation and subsequent loss of infectivity occurs even under natural conditions. 

In conclusion, the results in the current study indicate that removal of furniture that had been in contact with scrapie-infected animals should be recommended, particularly since cleaning and decontamination may not effectively remove scrapie infectivity (31), even though infectivity declines considerably if the pasture and the field furniture have not been in contact with scrapie-infected sheep for several months. As sPMCA failed to detect PrPSc in furniture that was subjected to weathering, even though exposure led to infection in sheep, this method may not always be reliable in predicting the risk of scrapie infection through environmental contamination. 

These results suggest that the VRQ/VRQ sheep model may be more sensitive than sPMCA for the detection of environmentally associated scrapie, and suggest that extremely low levels of scrapie contamination are able to cause infection in susceptible sheep genotypes. 

Keywords: classical scrapie, prion, transmissible spongiform encephalopathy, sheep, field furniture, reservoir, serial protein misfolding cyclic amplification 

Wednesday, December 16, 2015 

*** Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission *** 


CWD, TSE, PRION, MATERNAL mother to offspring, testes, epididymis, seminal fluid, and blood




Cervid to human prion transmission 5R01NS088604-04 Update

MONDAY, APRIL 01, 2019 

PUBLIC HEALTH U of M launches Chronic Wasting Disease Program to address potential health crisis

cattle, pigs, sheep, cwd, tse, prion, oh my!

***> In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006). 

Sheep and cattle may be exposed to CWD via common grazing areas with affected deer but so far, appear to be poorly susceptible to mule deer CWD (Sigurdson, 2008). In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006). It is not known how susceptible humans are to CWD but given that the prion can be present in muscle, it is likely that humans have been exposed to the agent via consumption of venison (Sigurdson, 2008). Initial experimental research suggests that human susceptibility to CWD is low and there may be a robust species barrier for CWD transmission to humans (Sigurdson, 2008), however the risk appetite for a public health threat may still find this level unacceptable.

cwd scrapie pigs oral routes

***> 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. 

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


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.


36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011).

The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE).

Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.


The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008).


In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.


In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible... For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.


Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents.


TUESDAY, APRIL 18, 2017 


Prion Conference 2018

O5 Prion Disease in Dromedary Camels 

Babelhadj B (1), Di Bari MA (2), Pirisinu L (2), Chiappini B (2), Gaouar SB (3), Riccardi G (2), Marcon S (2), Agrimi U (2), Nonno R (2), Vaccari G (2) (1) École Normale Supérieure Ouargla. Laboratoire de protection des écosystèmes en zones arides et semi arides University Kasdi Merbah Ouargla, Ouargla, Algeria; (2) Istituto Superiore di Sanità, Department of Food Safety, Nutrition and Veterinary Public Health, Rome, Italy (3) University Abou Bekr Bélkaid, Tlemcen, Algeria. 

Prions are responsible for fatal and transmissible neurodegenerative diseases including CreutzfeldtJakob disease in humans, scrapie in small ruminants and bovine spongiform encephalopathy (BSE). Following the BSE epidemic and the demonstration of its zoonotic potential, general concerns have been raised on animal prions. 

Here we report the identification of a prion disease in dromedary camels (Camelus dromedarius) in Algeria and designate it as Camel Prion Disease (CPD). In the last years, neurological symptoms have been observed in adult male and female dromedaries presented for slaughter at the Ouargla abattoir. The symptoms include weight loss, behavioral abnormalities and neurological symptoms such as tremors, aggressiveness, hyper-reactivity, typical down and upwards movements of the head, hesitant and uncertain gait, ataxia of the hind limbs, occasional falls and difficult getting up. During 2015 and 2016, symptoms suggestive of prion disease were observed in 3.1% of 2259 dromedaries presented at ante-mortem examination. Laboratory diagnosis was obtained in three symptomatic dromedaries, sampled in 2016 and 2017, by the detection of typical neurodegeneration and disease-specific prion protein (PrPSc) in brain tissues. 

Histopathological examination revealed spongiform change, gliosis and neuronal loss preferentially in grey matter of subcortical brain areas. Abundant PrPSc deposition was detected in the same brain areas by immunohistochemistry and PET-blot. Western blot analysis confirmed the presence of PK-resistant PrPSc, whose N-terminal cleaved PK-resistant core was characterized by a mono-glycosylated dominant form and by a distinctive N-terminal cleavage, different from that observed in BSE and scrapie. 

PrPSc was also detected, by immunohistochemistry, in all sampled lymph nodes (cervical, prescapular and lumbar aortic) of the only animal from which they were collected. 

The PRNP sequence of the two animals for which frozen material was available, showed 100% nucleotide identity with the PRNP sequence already reported for dromedary camel. 

Overall, these data demonstrate the presence of a prion disease in dromedary camelswhose nature, origin and spread need further investigations. However, our preliminary observations on the rather high prevalence of symptomatic dromedaries and the involvement of lymphoid tissues, are consistent with CPD being an infectious disease. In conclusion, the emergence of a new prion disease in a livestock species of crucial importance for millions of people around the world, makes urgent to assess the risk for humans and to develop policies able to control the spread of the disease in animals and to minimize human exposure. 


New Outbreak of TSE Prion in NEW LIVESTOCK SPECIES

Mad Camel Disease

Volume 24, Number 6—June 2018 Research 

Prion Disease in Dromedary Camels, Algeria

Prions cause fatal and transmissible neurodegenerative diseases, including Creutzfeldt-Jakob disease in humans, scrapie in small ruminants, and bovine spongiform encephalopathy (BSE). After the BSE epidemic, and the associated human infections, began in 1996 in the United Kingdom, general concerns have been raised about animal prions. We detected a prion disease in dromedary camels (Camelus dromedarius) in Algeria. Symptoms suggesting prion disease occurred in 3.1% of dromedaries brought for slaughter to the Ouargla abattoir in 2015–2016. We confirmed diagnosis by detecting pathognomonic neurodegeneration and disease-specific prion protein (PrPSc) in brain tissues from 3 symptomatic animals. Prion detection in lymphoid tissues is suggestive of the infectious nature of the disease. PrPSc biochemical characterization showed differences with BSE and scrapie. Our identification of this prion disease in a geographically widespread livestock species requires urgent enforcement of surveillance and assessment of the potential risks to human and animal health.


The possibility that dromedaries acquired the disease from eating prion-contaminated waste needs to be considered.
Tracing the origin of prion diseases is challenging. In the case of CPD, the traditional extensive and nomadic herding practices of dromedaries represent a formidable factor for accelerating the spread of the disease at long distances, making the path of its diffusion difficult to determine. Finally, the major import flows of live animals to Algeria from Niger, Mali, and Mauritania (27) should be investigated to trace the possible origin of CPD from other countries.
Camels are a vital animal species for millions of persons globally. The world camel population has a yearly growth rate of 2.1% (28). In 2014, the population was estimated at ≈28 million animals, but this number is probably underestimated.. Approximately 88% of camels are found in Africa, especially eastern Africa, and 12% are found in Asia. Official data reported 350,000 dromedaries in Algeria in 2014 (28).
On the basis of phenotypic traits and sociogeographic criteria, several dromedary populations have been suggested to exist in Algeria (29). However, recent genetic studies in Algeria and Egypt point to a weak differentiation of the dromedary population as a consequence of historical use as a cross-continental beast of burden along trans-Saharan caravan routes, coupled with traditional extensive/nomadic herding practices (30).
Such genetic homogeneity also might be reflected in PRNP. Studies on PRNP variability in camels are therefore warranted to explore the existence of genotypes resistant to CPD, which could represent an important tool for CPD management as it was for breeding programs for scrapie eradication in sheep.
In the past 10 years, the camel farming system has changed rapidly, with increasing setup of periurban dairy farms and dairy plants and diversification of camel products and market penetration (13). This evolution requires improved health standards for infectious diseases and, in light of CPD, for prion diseases.
The emergence of another prion disease in an animal species of crucial importance for millions of persons worldwide makes it necessary to assess the risk for humans and develop evidence-based policies to control and limit the spread of the disease in animals and minimize human exposure. The implementation of a surveillance system for prion diseases would be a first step to enable disease control and minimize human and animal exposure. Finally, the diagnostic capacity of prion diseases needs to be improved in all countries in Africa where dromedaries are part of the domestic livestock.




O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations 

Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France 

Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). 

Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods. 

*** 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. 

We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health. 


***thus questioning the origin of human sporadic cases*** 


***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals. 


***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. 


Saturday, April 23, 2016

SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016

Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online

Taylor & Francis

Prion 2016 Animal Prion Disease Workshop Abstracts

WS-01: Prion diseases in animals and zoonotic potential

Juan Maria Torres a, Olivier Andreoletti b, J uan-Carlos Espinosa a. Vincent Beringue c. Patricia Aguilar a,

Natalia Fernandez-Borges a. and Alba Marin-Moreno a

"Centro de Investigacion en Sanidad Animal ( CISA-INIA ). Valdeolmos, Madrid. Spain; b UMR INRA -ENVT 1225 Interactions Holes Agents Pathogenes. ENVT. Toulouse. France: "UR892. Virologie lmmunologie MolécuIaires, Jouy-en-Josas. France

Dietary exposure to bovine spongiform encephalopathy (BSE) contaminated bovine tissues is considered as the origin of variant Creutzfeldt Jakob (vCJD) disease in human. To date, BSE agent is the only recognized zoonotic prion... Despite the variety of Transmissible Spongiform Encephalopathy (TSE) agents that have been circulating for centuries in farmed ruminants there is no apparent epidemiological link between exposure to ruminant products and the occurrence of other form of TSE in human like sporadic Creutzfeldt Jakob Disease (sCJD). However, the zoonotic potential of the diversity of circulating TSE agents has never been systematically assessed. The major issue in experimental assessment of TSEs zoonotic potential lies in the modeling of the ‘species barrier‘, the biological phenomenon that limits TSE agents’ propagation from a species to another. In the last decade, mice genetically engineered to express normal forms of the human prion protein has proved essential in studying human prions pathogenesis and modeling the capacity of TSEs to cross the human species barrier.

To assess the zoonotic potential of prions circulating in farmed ruminants, we study their transmission ability in transgenic mice expressing human PrPC (HuPrP-Tg). Two lines of mice expressing different forms of the human PrPC (129Met or 129Val) are used to determine the role of the Met129Val dimorphism in susceptibility/resistance to the different agents.

These transmission experiments confirm the ability of BSE prions to propagate in 129M- HuPrP-Tg mice and demonstrate that Met129 homozygotes may be susceptible to BSE in sheep or goat to a greater degree than the BSE agent in cattle and that these agents can convey molecular properties and neuropathological indistinguishable from vCJD. However homozygous 129V mice are resistant to all tested BSE derived prions independently of the originating species suggesting a higher transmission barrier for 129V-PrP variant.

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. 

***> 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.



Title: 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. 

***> 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. <***

Transmission of scrapie prions to primate after an extended silent incubation period 

Emmanuel E. Comoy, Jacqueline Mikol, Sophie Luccantoni-Freire, Evelyne Correia, Nathalie Lescoutra-Etchegaray, Valérie Durand, Capucine Dehen, Olivier Andreoletti, Cristina Casalone, Juergen A. Richt, Justin J. Greenlee, Thierry Baron, Sylvie L. Benestad, Paul Brown & Jean-Philippe Deslys Scientific Reports volume 5, Article number: 11573 (2015) | Download Citation


Classical bovine spongiform encephalopathy (c-BSE) is the only animal prion disease reputed to be zoonotic, causing variant Creutzfeldt-Jakob disease (vCJD) in humans and having guided protective measures for animal and human health against animal prion diseases. Recently, partial transmissions to humanized mice showed that the zoonotic potential of scrapie might be similar to c-BSE. We here report the direct transmission of a natural classical scrapie isolate to cynomolgus macaque, a highly relevant model for human prion diseases, after a 10-year silent incubation period, with features similar to those reported for human cases of sporadic CJD. Scrapie is thus actually transmissible to primates with incubation periods compatible with their life expectancy, although fourfold longer than BSE. Long-term experimental transmission studies are necessary to better assess the zoonotic potential of other prion diseases with high prevalence, notably Chronic Wasting Disease of deer and elk and atypical/Nor98 scrapie.


Discussion We describe the transmission of spongiform encephalopathy in a non-human primate inoculated 10 years earlier with a strain of sheep c-scrapie. Because of this extended incubation period in a facility in which other prion diseases are under study, we are obliged to consider two alternative possibilities that might explain its occurrence. We first considered the possibility of a sporadic origin (like CJD in humans). Such an event is extremely improbable because the inoculated animal was 14 years old when the clinical signs appeared, i.e. about 40% through the expected natural lifetime of this species, compared to a peak age incidence of 60–65 years in human sporadic CJD, or about 80% through their expected lifetimes. 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.

The second possibility is a laboratory cross-contamination. Three facts make this possibility equally unlikely. First, handling of specimens in our laboratory is performed with fastidious attention to the avoidance of any such cross-contamination. Second, no laboratory cross-contamination has ever been documented in other primate laboratories, including the NIH, even between infected and uninfected animals housed in the same or adjacent cages with daily intimate contact (P. Brown, personal communication). Third, the cerebral lesion profile is different from all the other prion diseases we have studied in this model19, with a correlation between cerebellar lesions (massive spongiform change of Purkinje cells, intense PrPres staining and reactive gliosis26) and ataxia. The iron deposits present in the globus pallidus are a non specific finding that have been reported previously in neurodegenerative diseases and aging27. Conversely, the thalamic lesion was reminiscent of a metabolic disease due to thiamine deficiency28 but blood thiamine levels were within normal limits (data not shown). The preferential distribution of spongiform change in cortex associated with a limited distribution in the brainstem is reminiscent of the lesion profile in MM2c and VV1 sCJD patients29, but interspecies comparison of lesion profiles should be interpreted with caution. It is of note that the same classical scrapie isolate induced TSE in C57Bl/6 mice with similar incubation periods and lesional profiles as a sample derived from a MM1 sCJD patient30.

We are therefore confident that the illness in this cynomolgus macaque represents a true transmission of a sheep c-scrapie isolate directly to an old-world monkey, which taxonomically resides in the primate subdivision (parvorder of catarrhini) that includes humans. With an homology of its PrP protein with humans of 96.4%31, cynomolgus macaque constitutes a highly relevant model for assessing zoonotic risk of prion diseases. Since our initial aim was to show the absence of transmission of scrapie to macaques in the worst-case scenario, we obtained materials from a flock of naturally-infected sheep, affecting animals with different genotypes32. This c-scrapie isolate exhibited complete transmission in ARQ/ARQ sheep (332 ± 56 days) and Tg338 transgenic mice expressing ovine VRQ/VRQ prion protein (220 ± 5 days) (O. Andreoletti, personal communication). From the standpoint of zoonotic risk, it is important to note that sheep with c-scrapie (including the isolate used in our study) have demonstrable infectivity throughout their lymphoreticular system early in the incubation period of the disease (3 months-old for all the lymphoid organs, and as early as 2 months-old in gut-associated lymph nodes)33. In addition, scrapie infectivity has been identified in blood34, milk35 and skeletal muscle36 from asymptomatic but scrapie infected small ruminants which implies a potential dietary exposure for consumers.

Two earlier studies have reported the occurrence of clinical TSE in cynomolgus macaques after exposures to scrapie isolates. In the first study, the “Compton” scrapie isolate (derived from an English sheep) and serially propagated for 9 passages in goats did not transmit TSE in cynomolgus macaque, rhesus macaque or chimpanzee within 7 years following intracerebral challenge1; conversely, after 8 supplementary passages in conventional mice, this “Compton” isolate induced TSE in a cynomolgus macaque 5 years after intracerebral challenge, but rhesus macaques and chimpanzee remained asymptomatic 8.5 years post-exposure8. However, multiple successive passages that are classically used to select laboratory-adapted prion strains can significantly modify the initial properties of a scrapie isolate, thus questioning the relevance of zoonotic potential for the initial sheep-derived isolate. The same isolate had also induced disease into squirrel monkeys (new-world monkey)9. A second historical observation reported that a cynomolgus macaque developed TSE 6 years post-inoculation with brain homogenate from a scrapie-infected Suffolk ewe (derived from USA), whereas a rhesus macaque and a chimpanzee exposed to the same inoculum remained healthy 9 years post-exposure1. This inoculum also induced TSE in squirrel monkeys after 4 passages in mice. Other scrapie transmission attempts in macaque failed but had more shorter periods of observation in comparison to the current study. Further, it is possible that there are differences in the zoonotic potential of different scrapie strains.

The most striking observation in our study is the extended incubation period of scrapie in the macaque model, which has several implications. Firstly, our observations constitute experimental evidence in favor of the zoonotic potential of c-scrapie, at least for this isolate that has been extensively studied32,33,34,35,36. The cross-species zoonotic ability of this isolate should be confirmed by performing duplicate intracerebral exposures and assessing the transmissibility by the oral route (a successful transmission of prion strains through the intracerebral route may not necessarily indicate the potential for oral transmission37). However, such confirmatory experiments may require more than one decade, which is hardly compatible with current general management and support of scientific projects; thus this study should be rather considered as a case report.

Secondly, transmission of c-BSE to primates occurred within 8 years post exposure for the lowest doses able to transmit the disease (the survival period after inoculation is inversely proportional to the initial amount of infectious inoculum). The occurrence of scrapie 10 years after exposure to a high dose (25 mg) of scrapie-infected sheep brain suggests that the macaque has a higher species barrier for sheep c-scrapie than c-BSE, although it is notable that previous studies based on in vitro conversion of PrP suggested that BSE and scrapie prions would have a similar conversion potential for human PrP38.

Thirdly, prion diseases typically have longer incubation periods after oral exposure than after intracerebral inoculations: since humans can develop Kuru 47 years after oral exposure39, an incubation time of several decades after oral exposure to scrapie would therefore be expected, leading the disease to occur in older adults, i.e. the peak age for cases considered to be sporadic disease, and making a distinction between scrapie-associated and truly sporadic disease extremely difficult to appreciate.

Fourthly, epidemiologic evidence is necessary to confirm the zoonotic potential of an animal disease suggested by experimental studies. A relatively short incubation period and a peculiar epidemiological situation (e.g., all the first vCJD cases occurring in the country with the most important ongoing c-BSE epizootic) led to a high degree of suspicion that c-BSE was the cause of vCJD. Sporadic CJD are considered spontaneous diseases with an almost stable and constant worldwide prevalence (0.5–2 cases per million inhabitants per year), and previous epidemiological studies were unable to draw a link between sCJD and classical scrapie6,7,40,41, even though external causes were hypothesized to explain the occurrence of some sCJD clusters42,43,44. However, extended incubation periods exceeding several decades would impair the predictive values of epidemiological surveillance for prion diseases, already weakened by a limited prevalence of prion diseases and the multiplicity of isolates gathered under the phenotypes of “scrapie” and “sporadic CJD”.

Fifthly, considering this 10 year-long incubation period, together with both laboratory and epidemiological evidence of decade or longer intervals between infection and clinical onset of disease, no premature conclusions should be drawn from negative transmission studies in cynomolgus macaques with less than a decade of observation, as in the aforementioned historical transmission studies of scrapie to primates1,8,9. Our observations and those of others45,46 to date are unable to provide definitive evidence regarding the zoonotic potential of CWD, atypical/Nor98 scrapie or H-type BSE. The extended incubation period of the scrapie-affected macaque in the current study also underscores the limitations of rodent models expressing human PrP for assessing the zoonotic potential of some prion diseases since their lifespan remains limited to approximately two years21,47,48. This point is illustrated by the fact that the recently reported transmission of scrapie to humanized mice was not associated with clinical signs for up to 750 days and occurred in an extreme minority of mice with only a marginal increase in attack rate upon second passage13. The low attack rate in these studies is certainly linked to the limited lifespan of mice compared to the very long periods of observation necessary to demonstrate the development of scrapie. Alternatively, one could estimate that a successful second passage is the result of strain adaptation to the species barrier, thus poorly relevant of the real zoonotic potential of the original scrapie isolate of sheep origin49. The development of scrapie in this primate after an incubation period compatible with its lifespan complements the study conducted in transgenic (humanized) mice; taken together these studies suggest that some isolates of sheep scrapie can promote misfolding of the human prion protein and that scrapie can develop within the lifespan of some primate species.

In addition to previous studies on scrapie transmission to primate1,8,9 and the recently published study on transgenic humanized mice13, our results constitute new evidence for recommending that the potential risk of scrapie for human health should not be dismissed. Indeed, human PrP transgenic mice and primates are the most relevant models for investigating the human transmission barrier. To what extent such models are informative for measuring the zoonotic potential of an animal TSE under field exposure conditions is unknown. During the past decades, many protective measures have been successfully implemented to protect cattle from the spread of c-BSE, and some of these measures have been extended to sheep and goats to protect from scrapie according to the principle of precaution. Since cases of c-BSE have greatly reduced in number, those protective measures are currently being challenged and relaxed in the absence of other known zoonotic animal prion disease. We recommend that risk managers should be aware of the long term potential risk to human health of at least certain scrapie isolates, notably for lymphotropic strains like the classical scrapie strain used in the current study. Relatively high amounts of infectivity in peripheral lymphoid organs in animals infected with these strains could lead to contamination of food products produced for human consumption. Efforts should also be maintained to further assess the zoonotic potential of other animal prion strains in long-term studies, notably lymphotropic strains with high prevalence like CWD, which is spreading across North America, and atypical/Nor98 scrapie (Nor98)50 that was first detected in the past two decades and now represents approximately half of all reported cases of prion diseases in small ruminants worldwide, including territories previously considered as scrapie free... 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.



November 2013...TSS

Singeltary Submission Environmental Impact Statements; Availability, etc.: Animal Carcass Management [Docket No. APHIS-2013-0044]

Sunday, November 3, 2013

Environmental Impact Statements; Availability, etc.: Animal Carcass Management [Docket No. APHIS-2013-0044]



EFSA Panel on Biological Hazards (BIOHAZ) Antonia Ricci Ana Allende Declan Bolton Marianne Chemaly Robert Davies Pablo Salvador Fernández Escámez ... See all authors 

First published: 17 January 2018 ;

also, see; 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.


The tissue distribution of infectivity in CWD‐infected cervids is now known to extend beyond CNS and lymphoid tissues. While the removal of these specific tissues from the food chain would reduce human dietary exposure to infectivity, exclusion from the food chain of the whole carcass of any infected animal would be required to eliminate human dietary exposure.

zoonosis zoonotic cervid tse prion cwd to humans, preparing for the storm

***An alternative to modeling the species barrier is the cell-free conversion assay which points to CWD as the animal prion disease with the greatest zoonotic potential, after (and very much less than) BSE.116***

Scientific Advisors and Consultants Staff 2001 Advisory Committee TSE PRION Singeltary Submission 


Monday, January 08,2001 3:03 PM 

FDA Singeltary submission 2001 

Greetings again Dr. Freas and Committee Members, 

I wish to submit the following information to the Scientific Advisors and Consultants Staff 2001 Advisory Committee (short version). I understand the reason of having to shorten my submission, but only hope that you add it to a copy of the long version, for members to take and read at their pleasure, (if cost is problem, bill me, address below). So when they realize some time in the near future of the 'real' risks i speak of from human/animal TSEs and blood/surgical products. I cannot explain the 'real' risk of this in 5 or 10 minutes at some meeting, or on 2 or 3 pages, but will attempt here: 

fda link is dead in the water; 

snip...see full text 

CHRONIC WASTING DISEASE CONGRESS Serial No. 107-117 May 16, 2002



May 16, 2002

Serial No. 107-117


Mr. MCINNIS. Today, this joint Subcommittee hearing will explore an issue of immeasurable importance to the growing number of communities in wide-ranging parts of this country, the growing incidence of Chronic Wasting Disease in North America’s wild and captive deer and elk populations. In a matter of just a few months, this once parochial concern has grown into something much larger and much more insidious than anyone could have imagined or predicted.

As each day passes, this problem grows in its size, scope, and consequence. One thing becomes clear. Chronic Wasting Disease is not a Colorado problem. It is a Wisconsin problem or a Nebraska or Wyoming problem. It is a national problem and anything short of a fully integrated, systematic national assault on this simply will not do, which is precisely why we brought our group together here today.


So this is a disease that is spreading throughout the continent and it is going to require a national response as well as the efforts that are currently taking place in States like Wisconsin, Colorado, Nebraska, Wyoming, the interest they now have down in Texas and some of the neighboring States that have large white-tailed deer population and also elk.

This is a huge issue for us, Mr. Chairman, in the State of Wisconsin. I want to commend Governor McCallum and your staff and the various agencies for the rapid response that you have shown, given the early detection of CWD after the last deer hunting season. The problem that we have, though, is just a lack of information, good science in regards to what is the best response, how dangerous is this disease. We cannot close the door, quite frankly, with the paucity of scientific research that is out there right now in regards to how the disease spreads, the exposure of other livestock herds—given the importance of our dairy industry in the State, that is a big issue—and also the human health effects.

FRIDAY, MARCH 30, 2018

Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification Program Standards Singeltary Submission March 30, 2018

THURSDAY, JUNE 07, 2018 

Michigan DNR to present chronic wasting disease recommendations to Natural Resources Commission Singeltary submission


Montana Chronic Wasting Disease CWD TSE Prion Response Plan Singeltary Submission


CWD PLAN Singeltary Submission Comment New York State DEC


TEXAS TPWD Sets Public Hearings on Deer Movement Rule Proposals in Areas with CWD Rule Terry S. Singeltary Sr. comment submission

Wednesday, November 09, 2016

Chronic Wasting Disease (CWD) Program Standards - Review and Comment By Terry S Singeltary Sr. November 9, 2016

Singeltary submission ;

Program Standards: Chronic Wasting Disease Herd Certification Program and Interstate Movement of Farmed or Captive Deer, Elk, and Moose

DOCUMENT ID: APHIS-2006-0118-0411

***Singeltary submission

Singeltary Submissions to EU on CWD TSE Prion

Friday, November 22, 2013

Wasting disease is threat to the entire UK deer population CWD TSE PRION disease in cervids


The Scottish Parliament's Rural Affairs, Climate Change and Environment Committee has been looking into deer management, as you can see from the following press release,

***and your email has been forwarded to the committee for information:

Friday, November 22, 2013

Wasting disease is threat to the entire UK deer population

Sunday, July 21, 2013

Welsh Government and Food Standards Agency Wales Joint Public Consultation on the Proposed Transmissible Spongiform Encephalopathies (Wales) Regulations 2013

*** Singeltary Submission WG18417

Sunday, June 23, 2013

National Animal Health Laboratory Network Reorganization Concept Paper (Document ID APHIS-2012-0105-0001)

***Terry S. Singeltary Sr. submission

Scientific Advisors and Consultants Staff 2001 Advisory Committee TSE PRION Singeltary Submission Freas Monday, January 08,2001 3:03 PM FDA Singeltary submission 2001 

Greetings again Dr. Freas and Committee Members, 

I wish to submit the following information to the Scientific Advisors and Consultants Staff 2001 Advisory Committee (short version). I understand the reason of having to shorten my submission, but only hope that you add it to a copy of the long version, for members to take and read at their pleasure, (if cost is problem, bill me, address below). So when they realize some time in the near future of the 'real' risks i speak of from human/animal TSEs and blood/surgical products. I cannot explain the 'real' risk of this in 5 or 10 minutes at some meeting, or on 2 or 3 pages, but will attempt here: 

fda link is dead in the water; 

snip...see full text 

Harvard BSE Risk Assessment Singeltary et al

Owens, Julie

From: Terry S. Singeltary Sr. []

Sent: Monday, July 24, 2006 1:09 PM

To: FSIS RegulationsComments

Subject: [Docket No. FSIS-2006-0011] FSIS Harvard Risk Assessment of Bovine Spongiform Encephalopathy (BSE)

Page 1 of 98


Greetings FSIS, 

I would kindly like to comment on the following ;

[Federal Register: July 12, 2006 (Volume 71, Number 133)] [Notices] [Page 39282-39283] From the Federal Register Online via GPO Access [] [DOCID:fr12jy06-35] 

Response to Singeltary et al

SUNDAY, FEBRUARY 14, 2010 [Docket No. FSIS-2006-0011] FSIS Harvard Risk Assessment of Bovine Spongiform Encephalopathy (BSE) Suppressed peer review of Harvard study October 31, 2002. 

October 31, 2002 Review of the Evaluation of the Potential for Bovine Spongiform Encephalopathy in the United States Conducted by the Harvard Center for Risk Analysis, Harvard School of Public Health and Center for Computational Epidemiology, College of Veterinary Medicine, Tuskegee University Final Report Prepared for U.S. Department of Agriculture Food Safety and Inspection Service Office of Public Health and Science Prepared by RTI Health, Social, and Economics Research Research Triangle Park, NC 27709 RTI Project Number 07182.024 

*** U.S.A. 50 STATE BSE MAD COW CONFERENCE CALL Jan. 9, 2001 Singeltary et al


BSE infectivity survives burial for five years with only limited spread






Cervid to human prion transmission 5R01NS088604-04 Update

MONDAY, APRIL 01, 2019 

PUBLIC HEALTH U of M launches Chronic Wasting Disease Program to address potential health crisis


Estimating the amount of Chronic Wasting Disease infectivity passing through abattoirs and field slaughter

Saturday, December 15, 2018 


PLOS ONE Journal 

IBNC Tauopathy or TSE Prion disease, it appears, no one is sure 

Terry S. Singeltary Sr., 03 Jul 2015 at 16:53 GMT

***however in 1 C-type challenged animal, Prion 2015 Poster Abstracts S67 PrPsc was not detected using rapid tests for BSE.

***Subsequent testing resulted in the detection of pathologic lesion in unusual brain location and PrPsc detection by PMCA only.

*** IBNC Tauopathy or TSE Prion disease, it appears, no one is sure ***

*** Singeltary reply ; Molecular, Biochemical and Genetic Characteristics of BSE in Canada Singeltary reply ;

MONDAY, MAY 20, 2019 

Tracking and clarifying differential traits of classical- and atypical L-type bovine spongiform encephalopathy prions after transmission from cattle to cynomolgus monkeys

SUNDAY, APRIL 14, 2019 

Estimation of prion infectivity in tissues of cattle infected with atypical BSE by real time-quaking induced conversion assay


USDA Announces Atypical Bovine Spongiform Encephalopathy Detection Aug 29, 2018 A Review of Science 2019

Diagnosis and Reporting of Creutzfeldt-Jakob Disease 

Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA Diagnosis and Reporting of Creutzfeldt-Jakob Disease 

To the Editor: 

In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally.. 

Terry S. Singeltary, Sr Bacliff, Tex 

1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Creutzfeldt-Jakob disease in the United States: 1979-1998. JAMA. 2000;284:2322-2323. 

doi:10.1016/S1473-3099(03)00715-1 Copyright © 2003 Published by Elsevier Ltd. Newsdesk

Tracking spongiform encephalopathies in North America

Xavier Bosch

Available online 29 July 2003. 

Volume 3, Issue 8, August 2003, Page 463 

“My name is Terry S Singeltary Sr, and I live in Bacliff, Texas. I lost my mom to hvCJD (Heidenhain variant CJD) and have been searching for answers ever since. What I have found is that we have not been told the truth. CWD in deer and elk is a small portion of a much bigger problem..” ............................ 

January 28, 2003; 60 (2) VIEWS & REVIEWS

Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States

Ermias D. Belay, Ryan A. Maddox, Pierluigi Gambetti, Lawrence B. Schonberger

First published January 28, 2003, DOI:


Transmissible spongiform encephalopathies (TSEs) attracted increased attention in the mid-1980s because of the emergence among UK cattle of bovine spongiform encephalopathy (BSE), which has been shown to be transmitted to humans, causing a variant form of Creutzfeldt-Jakob disease (vCJD). The BSE outbreak has been reported in 19 European countries, Israel, and Japan, and human cases have so far been identified in four European countries, and more recently in a Canadian resident and a US resident who each lived in Britain during the BSE outbreak. To monitor the occurrence of emerging forms of CJD, such as vCJD, in the United States, the Centers for Disease Control and Prevention has been conducting surveillance for human TSEs through several mechanisms, including the establishment of the National Prion Disease Pathology Surveillance Center. Physicians are encouraged to maintain a high index of suspicion for vCJD and use the free services of the pathology center to assess the neuropathology of clinically diagnosed and suspected cases of CJD or other TSEs.

Received May 7, 2002. Accepted August 28, 2002.

RE-Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States 

Terry S. Singeltary, retired (medically) 

Published March 26, 2003

26 March 2003

Terry S. Singeltary, retired (medically) CJD WATCH

I lost my mother to hvCJD (Heidenhain Variant CJD). I would like to comment on the CDC's attempts to monitor the occurrence of emerging forms of CJD. Asante, Collinge et al [1] have reported that BSE transmission to the 129-methionine genotype can lead to an alternate phenotype that is indistinguishable from type 2 PrPSc, the commonest sporadic CJD. However, CJD and all human TSEs are not reportable nationally. CJD and all human TSEs must be made reportable in every state and internationally. I hope that the CDC does not continue to expect us to still believe that the 85%+ of all CJD cases which are sporadic are all spontaneous, without route/source. We have many TSEs in the USA in both animal and man. CWD in deer/elk is spreading rapidly and CWD does transmit to mink, ferret, cattle, and squirrel monkey by intracerebral inoculation. With the known incubation periods in other TSEs, oral transmission studies of CWD may take much longer. Every victim/family of CJD/TSEs should be asked about route and source of this agent. To prolong this will only spread the agent and needlessly expose others. In light of the findings of Asante and Collinge et al, there should be drastic measures to safeguard the medical and surgical arena from sporadic CJDs and all human TSEs. I only ponder how many sporadic CJDs in the USA are type 2 PrPSc?

Reply to Singletary Ryan A. Maddox, MPH Other Contributors: Published March 26, 2003 

Mr. Singletary raises several issues related to current Creutzfeldt- Jakob disease (CJD) surveillance activities. Although CJD is not a notifiable disease in most states, its unique characteristics, particularly its invariably fatal outcome within usually a year of onset, make routine mortality surveillance a useful surrogate for ongoing CJD surveillance.[1] In addition, because CJD is least accurately diagnosed early in the course of illness, notifiable-disease surveillance could be less accurate than, if not duplicative of, current mortality surveillance.[1] However, in states where making CJD officially notifiable would meaningfully facilitate the collection of data to monitor for variant CJD (vCJD) or other emerging prion diseases, CDC encourages the designation of CJD as a notifiable disease.[1] Moreover, CDC encourages physicians to report any diagnosed or suspected CJD cases that may be of special public health importance (e.g...., vCJD, iatrogenic CJD, unusual CJD clusters).

As noted in our article, strong evidence is lacking for a causal link between chronic wasting disease (CWD) of deer and elk and human disease,[2] but only limited data seeking such evidence exist. Overall, the previously published case-control studies that have evaluated environmental sources of infection for sporadic CJD have not consistently identified strong evidence for a common risk factor.[3] However, the power of a case-control study to detect a rare cause of CJD is limited, particularly given the relatively small number of subjects generally involved and its long incubation period, which may last for decades. Because only a very small proportion of the US population has been exposed to CWD, a targeted surveillance and investigation of unusual cases or case clusters of prion diseases among persons at increased risk of exposure to CWD is a more efficient approach to detecting the possible transmission of CWD to humans. In collaboration with appropriate local and state health departments and the National Prion Disease Pathology Surveillance Center, CDC is facilitating or conducting such surveillance and case- investigations, including related laboratory studies to characterize CJD and CWD prions.

Mr. Singletary also expresses concern over a recent publication by Asante and colleagues indicating the possibility that some sporadic CJD cases may be attributable to bovine spongiform encephalopathy (BSE).[4] The authors reported that transgenic mice expressing human prion protein homozygous for methionine at codon 129, when inoculated with BSE prions, developed a molecular phenotype consistent with a subtype of sporadic CJD. Although the authors implied that BSE might cause a sporadic CJD-like illness among persons homozygous for methionine, the results of their research with mice do not necessarily directly apply to the transmission of BSE to humans. If BSE causes a sporadic CJD-like illness in humans, an increase in sporadic CJD cases would be expected to first occur in the United Kingdom, where the vast majority of vCJD cases have been reported. In the United Kingdom during 1997 through 2002, however, the overall average annual mortality rate for sporadic CJD was not elevated; it was about 1 case per million population per year. In addition, during this most recent 6-year period following the first published description of vCJD in 1996, there was no increasing trend in the reported annual number of UK sporadic CJD deaths.[3, 5] Furthermore, surveillance in the UK has shown no increase in the proportion of sporadic CJD cases that are homozygous for methionine (Will RG, National CJD Surveillance Unit, United Kingdom, 2003; personal communication)..


1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Diagnosis and reporting of Creutzfeldt-Jakob disease. JAMA 2001;285:733-734.

2. Belay ED, Maddox RA, Gambetti P, Schonberger LB. Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States. Neurology 2003;60:176-181.

3. Belay ED. Transmissible spongiform encephalopathies in humans. Annu Rev Microbiol 1999;53:283-314.

4. Asante EA, Linehan JM, Desbruslais M, et al. BSE prions propagate as either variant CJD-like or sporadic CJD-like prion strains in transgenic mice expressing human prion protein. EMBO J 2002;21:6358-6366.

5. The UK Creutzfeldt-Jakob Disease Surveillance Unit. CJD statistics. Available at: Accessed February 18, 2003.

Competing Interests: None declared.

Volume 2: Science 

4. The link between BSE and vCJD 

Summary 4.29 The evidence discussed above that vCJD is caused by BSE seems overwhelming. Uncertainties exist about the cause of CJD in farmers, their wives and in several abattoir workers. It seems that farmers at least might be at higher risk than others in the general population. 1 Increased ascertainment (ie, increased identification of cases as a result of greater awareness of the condition) seems unlikely, as other groups exposed to risk, such as butchers and veterinarians, do not appear to have been affected. The CJD in farmers seems to be similar to other sporadic CJD in age of onset, in respect to glycosylation patterns, and in strain-typing in experimental mice. Some farmers are heterozygous for the methionine/valine variant at codon 129, and their lymphoreticular system (LRS) does not contain the high levels of PrPSc found in vCJD. 

***>It remains a remote possibility that when older people contract CJD from BSE the resulting phenotype is like sporadic CJD and is distinct from the vCJD phenotype in younger people...end




***> Diagnosis of Methionine/Valine Variant Creutzfeldt-Jakob Disease by Protein Misfolding Cyclic Amplification 

Volume 24, Number 7—July 2018 Dispatch 

Diagnosis and Reporting of Creutzfeldt-Jakob Disease

2 January 2000 British Medical Journal U.S. 

Scientist should be concerned with a CJD epidemic in the U.S., as well 

15 November 1999 British Medical Journal hvCJD in the USA * BSE in U.S. 




Why did the appearance of new TSEs in animals matter so much? It has always been known that TSEs will transfer across species boundaries. The reason for this was never known until the genetic nature of the prion gene was fully investigated and found to be involved. The gene is found to have well preserved sites and as such there is a similar gene throughout the animal kingdom...and indeed a similar gene is found in insects! It is NOT clear that the precise close nature of the PrP gene structure is essention for low species barriers. Indeed it is probably easier to infect cats with BSE than it is to infect sheep. As such it is not clear that simply because it is possible to infect BSE from cattle into certain monkeys then other apes will necessarily be infectable with the disease. One factor has stood out, however, and that is that BSE, when inoculated into mice would retain its apparent nature of disease strain, and hence when it was inoculated back into cattle, then the same disease was produced. Similarly if the TSE from kudu was inoculated into mice then a similar distribution of disease in the brain of the mouse is seen as if BSE had been inoculated into the mouse. This phenomenon was not true with scrapie, in which the transmission across a species barrier was known to lose many of the scrapie strain phenomena in terms of incubation period or disease histopathology. This also suggested that BSE was not derived from scrapie originally but we probably will never know.
TSE in wild UK deer? The first case of BSE (as we now realise) was in a nyala in London zoo and the further zoo cases in ungulates were simply thought of as being interesting transmissions of scrapie initially. The big problem started to appear with animals in 1993-5 when it became clear that there was an increase in the CJD cases in people that had eaten deer although the statistics involved must have been questionable. The reason for this was that the CJD Surveillance was well funded to look into the diet of people dying of CJD. This effect is not clear with vCJD...if only because the numbers involved are much smaller and hence it is difficult to gain enough statistics. They found that many other foods did not appear to have much association at all but that deer certainly did and as years went by the association actually became clearer. The appearance of vCJD in 1996 made all this much more difficult in that it was suddenly clearer that the cases of sporadic CJD that they had been checking up until then probably had nothing to do with beef...and the study decreased. During the period there was an increasing worry that deer were involved with CJD..
see references:


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: <3daf5023 .4080804=""WT.NET"">

Dear Terry,

An excellent piece of review as this literature is desparately 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 =============== 

Stephen Dealler is a consultant medical microbiologist 

BSE Inquiry Steve Dealler

Management In Confidence

BSE: Private Submission of Bovine Brain Dealler

reports of sheep and calf carcasses dumped...

re-scrapie to cattle GAH Wells BSE Inquiry

Dr. Dealler goes rogue to confirm BSE

Confirmation BSE Dealler's mad cow

BSE vertical transmission

1993 cjd report finds relationship with eat venison and cjd increases 9 fold, let the cover up begin...tss


*** 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). ***

*** 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). ***

*** 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).


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).


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. ...


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 ; 




October 1994

Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge Spencers Lane 

BerksWell Coventry CV7 7BZ

Dear Mr Elmhirst,


Thank you for your recent letter concerning the publication of the third annual report from the CJD Surveillance Unit. I am sorry that you are dissatisfied with the way in which this report was published.

The Surveillance Unit is a completely independant outside body and the Department of Health is committed to publishing their reports as soon as they become available. In the circumstances it is not the practice to circulate the report for comment since the findings of the report would not be amended.. In future we can ensure that the British Deer Farmers Association receives a copy of the report in advance of publication.

The Chief Medical Officer has undertaken to keep the public fully informed of the results of any research in respect of CJD. This report was entirely the work of the unit and was produced completely independantly of the the Department.

The statistical results reqarding the consumption of venison was put into perspective in the body of the report and was not mentioned at all in the press release. Media attention regarding this report was low key but gave a realistic presentation of the statistical findings of the Unit. This approach to publication was successful in that consumption of venison was highlighted only once by the media ie. in the News at one television proqramme.

I believe that a further statement about the report, or indeed statistical links between CJD and consumption of venison, would increase, and quite possibly give damaging credence, to the whole issue. From the low key media reports of which I am aware it seems unlikely that venison consumption will suffer adversely, if at all. 

snip...see full text;




friendly fire, pass it forward, they call it iatrogenic cjd, or what i call 'tse prion poker', are you all in $$$


Medical Devices Containing Materials Derived from Animal Sources (Except for In Vitro Diagnostic Devices) Guidance for Industry and Food and Drug Administration Staff Document issued on March 15, 2019 Singeltary Submission

TUESDAY, APRIL 09, 2019 

Horizon Health Network Moncton Hospital notified more than 700 patients after two cases of CJD were diagnosed both patients had undergone cataracts surgery before being diagnosed

MONDAY, APRIL 8, 2019 

Studies Further Support Transmissibility of Alzheimer Disease–Associated Proteins

Thursday, December 1, 2016 


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. 





Chronic Wasting Disease CWD TSE Prion to Humans, who makes that final call, when, or, has it already happened?

TUESDAY, JUNE 13, 2017



First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress

FRIDAY, JUNE 16, 2017

P55 Susceptibility of human prion protein to in vitro conversion by chronic wasting disease prions

TUESDAY, JUNE 13, 2017

PRION 2017 CONFERENCE ABSTRACT Chronic Wasting Disease in European moose is associated with PrPSc features different from North American CWD

TUESDAY, JULY 04, 2017



P61 vCJD strain properties in a Spanish mother and son replicate as those of a young UK case

TUESDAY, JUNE 20, 2017 

Prion 2017 Conference Transmissible prions in the skin of Creutzfeldt-Jakob disease patients

Wednesday, May 24, 2017 

PRION2017 CONFERENCE VIDEO UPDATE 23 – 26 May 2017 Edinburgh UPDATE 1 

Subject: PRION2017 CONFERENCE VIDEO UPDATE 23 – 26 May 2017 Edinburgh

*see archives of previous Prion Conferences, the ones that are still available, scroll down towards bottom in this link.

MONDAY, MAY 02, 2016 

Zoonotic Potential of CWD Prions: An Update Prion 2016 Tokyo


PRION 2015


Saturday, May 30, 2015


PRION 2014

PRION 2013

PRION 2012

PRION 2011

Seven main threats for the future linked to prions

The NeuroPrion network has identified seven main threats for the future linked to prions.

First threat

The TSE road map defining the evolution of European policy for protection against prion diseases is based on a certain numbers of hypotheses some of which may turn out to be erroneous. In particular, a form of BSE (called atypical Bovine Spongiform Encephalopathy), recently identified by systematic testing in aged cattle without clinical signs, may be the origin of classical BSE and thus potentially constitute a reservoir, which may be impossible to eradicate if a sporadic origin is confirmed. Also, a link is suspected between atypical BSE and some apparently sporadic cases of Creutzfeldt-Jakob disease in humans. These atypical BSE cases constitute an unforeseen first threat that could sharply modify the European approach to prion diseases.

Second threat

In small ruminants, a new atypical form of scrapie currently represents up to 50% of detected cases and even involves sheep selected for resistance to classical scrapie. The consequences for animal and human health are still unknown and there may be a potential connection with atypical BSE. These atypical scrapie cases constitute a second threat not envisioned previously which could deeply modify the European approach to prion diseases.

Third threat

The species barrier between human and cattle might be weaker than previously expected and the risk of transmission of prion diseases between different species has been notoriously unpredictable. The emergence of new atypical strains in cattle and sheep together with the spread of chronic wasting disease in cervids renders the understanding of the species barrier critical. This constitutes a third threat not properly envisioned previously that could deeply modify the European approach to prion diseases.

Fourth threat

Prion infectivity has now been detected in blood, urine and milk and this has potential consequences on risk assessments for the environment and food as well as for contamination of surfaces including medical instruments. Furthermore the procedures recommended for decontamination of MBM (Meat and Bone Meal), which are based on older methodologies not designed for this purpose, have turned out to be of very limited efficacy and compromise current policies concerning the reuse of these high value protein supplements (cross-contamination of feed circuits are difficult to control). It should be noted that the destruction or very limited use of MBM is estimated to still cost 1 billion euros per year to the European economy, whereas other countries, including the US, Brazil, and Argentine do not have these constraints. However, many uncertainties remain concerning the guarantees that can be reasonably provided for food and feed safety and scientific knowledge about the causative agents (prions) will continue to evolve. This decontamination and environmental issue is a fourth threat that could modify deeply the European approach to prion diseases.

Fifth threat

The precise nature of prions remains elusive. Very recent data indicate that abnormal prion protein (PrPTSE) can be generated from the brains of normal animals, and under some conditions (including contaminated waste water) PrPTSE can be destroyed whereas the BSE infectious titre remains almost unchanged, a finding that underlines the possibility of having BSE without any detectable diagnostic marker. These are just two areas of our incomplete knowledge of the fundamental biology of prions which constitute a fifth threat to the European approach to prion diseases.

Sixth threat

The absence of common methods and standardisation in the evaluation of multiple in vivo models with different prion strains and different transgenic mice expressing PrP from different species (different genotypes of cattle, sheep, cervids, etc) renders a complete and comprehensive analysis of all the data generated by the different scientific groups almost impossible. This deeply impairs risk assessment. Moreover, the possibility of generating PrPTSE de novo with new powerful techniques has raised serious questions about their appropriateness for use as blood screening tests. The confusion about an incorrect interpretation of positive results obtained by these methods constitutes a sixth threat to European approach to prion diseases.

Seventh Threat

The detection of new or re-emerging prion diseases in animals or humans which could lead to a new crisis in consumer confidence over the relaxation of precautionary measures and surveillance programmes constitutes a seventh threat that could modify the European approach to prion diseases.

PRION 2010

PRION 2009



PRION October 8th - 10th 2008 Book of Abstracts 









*see archives of previous Prion Conferences, the ones that are still available, scroll down towards bottom in this link.

i do not advertise or make money from this, these blogs of tse prion science are for educational use. when i started to try and figure all this out was back in 1997, and the only available science for the lay public was from 


God Bless Dr. Tom Pringle. 

SO, i made a promise back then, i just made a promise to mom dod 12/14/97 confirmed Heidenhain Variant of Creutzfeldt Jakob Disease, never forget, and never let them forget.

this science on the tse prion should be made easy for the lay public to educate on the transmissible spongiform encephalopathy tse prion disease aka mad cow type disease.

wasted days and wasted nights...Freddy Fender

Terry S. Singeltary Sr.
Bacliff, Texas USA 77518 Galveston Bay, ...on the bottom!