Wyoming CWD Report monitoring efforts increase with focus on
improving herd health
CWD monitoring efforts increase with focus on improving herd
health
There have been no more new CWD cases
in the Pinedale and Jackson regions so far this fall.
11/28/2016 2:06:22 PM
Cheyenne - Monitoring the prevalence and distribution of chronic
wasting disease (CWD) is a priority for the Wyoming Game and Fish Department,
and the results of these efforts show limited numbers of new cases in the far
western Wyoming. Notably, there have been no more new CWD cases in the Pinedale
and Jackson regions so far this fall.
“Last year, we had a CWD-positive deer in Star Valley. It
was a priority for us to step up our surveillance in that area to try and keep
a close eye on the prevalence and distribution of CWD there. So far we
have not seen any additional positive deer in that part of the state,” said
Scott Edberg, deputy division chief of the Wildlife Division. “Game and Fish is
committed to maintaining an active surveillance effort there, and we are
greatly increasing our CWD efforts on our elk feedgrounds more than ever
before, including dedicated personnel to monitor and address CWD. We will keep
the public informed about the results of our efforts.”
Annual surveillance efforts for the disease in deer, elk,
and moose populations have been underway since the 2016 hunting season began.
As of Oct. 31, the Game and Fish Wildlife Health Lab analyzed 1,645 CWD
samples from around the state. Of those, 1,482 were from hunter-killed
animals with 85 positive CWD tests. Sixty-five samples came from targeted
animals-or animals showing signs of CWD, and 12 of those were positive.
The remaining 98 samples, from road-killed animals, resulted in four
positives. Game and Fish will continue its CWD sampling efforts for
the remainder of the 2016 hunting season as well as actively sample
target animals and road-kills throughout the year.
Three new deer hunt areas have been identified so far this year: hunt area 7
near Newcastle where a doe mule deer was harvested on Oct. 1; hunt area 128,
where a buck mule deer was harvested about 12 miles north of Dubois on Oct. 8;
and hunt area 110, west of Cody, where a buck mule deer was harvested on Oct.
28.
“Increased information helps Game and Fish execute our state CWD management
plan to try to slow the spread of CWD in the west and improve the health of the
herds,” Edberg said.
Game and Fish reminds hunters they play a significant role in monitoring the
distribution of this disease and provide valuable information for managing CWD.
If you see a deer, elk or moose that appears to be sick or not acting in a
normal manner, please contact your local game warden, wildlife biologist or Game and Fish
office immediately.
Please visit the Game and Fish website for more information on
chronic wasting disease transmission and regulations on transportation and
disposal of carcasses.
The Centers for Disease Control and the World Health Organization recommend
that people should not eat deer, elk or moose that test positive for CWD.
(Wyoming Game and Fish (307) 777-4600)
- WGFD -
https://wgfd.wyo.gov/News/CWD-monitoring-efforts-increase-with-focus-on-impr
Thursday,
November 17, 2016
Wyoming Game and Fish Department confirmed CWD
Deer Hunt Area 110 west of Cody
Wednesday, November 09, 2016
Wyoming Game and Fish Department confirmed chronic wasting disease
(CWD) in Deer Hunt Area 121, near Heart Mountain
Tuesday, October 18, 2016
WYOMING Game and Fish finds CWD in new deer hunt area near Dubois
and will more actively monitor elk feedgrounds
http://chronic-wasting-disease.blogspot.com/2016/10/wyoming-game-and-fish-finds-cwd-in-new_18.html
Sunday, October 16, 2016
Wyoming Game and Fish finds CWD in new deer hunt area near Osage
http://chronic-wasting-disease.blogspot.com/2016/10/wyoming-game-and-fish-finds-cwd-in-new.html
Tuesday, June 07, 2016
Wyoming
For the first time in several years an ungulate has tested positive for Chronic
Wasting Disease (CWD) on the west side of the continental divide
http://chronic-wasting-disease.blogspot.com/2016/06/wyoming-for-first-time-in-several-years.html
Wednesday, April 27, 2016
WYOMING
GAME AND FISH DEPARTMENT CHRONIC WASTING DISEASE MANAGEMENT PLAN APRIL 22, 2016
Thursday, March 10, 2016
WYOMING
RIDE EM COWBOY HELICOPTER WRANGLING RAMBO STYLE DEER BULLDOGGING RODEO FOR CWD
VIDEO
Monday, March 07, 2016
Wyoming
Game and Fish Department confirmed chronic wasting disease (CWD) in a buck mule
deer that was found dead southeast of Lander
Tuesday, January 12, 2016
Wyoming
Game and Fish seeks additional public comments on draft of updated CWD plan
Singeltary 2nd submission
From: Terry S. Singeltary
Sr.
Sent: Tuesday, January 12,
2016 3:52 PM
To: daryl.lutz@wgf.state.wy.us
Cc: Tara.Hodges@wyo.gov
; wyomingwildlife@wyo.gov ; Carrie.Little@wyo.gov
Subject: Game and Fish seeks
additional public comments on draft of updated CWD plan Singeltary 2nd
submission
Friday, November 18, 2016
IMPORTANT: SAWCorp CWD Test is NOT APHIS Approved
Horizontal Transmission
of Chronic Wasting Disease in Reindeer CDC Volume 22, Number 12—December 2016
Sunday, November 13, 2016
Horizontal Transmission of Chronic Wasting
Disease in Reindeer CDC Volume 22, Number 12—December 2016
CHRONIC WASTING DISEASE
CWD AND SCRAPIE TSE PRION ZOONOSIS UPDATE
*** WDA 2016 NEW YORK ***
We found that CWD adapts to a new host more readily than BSE and that
human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we
investigated the role of specific regions of the bovine, deer and human PrP protein
in resistance to conversion by prions from another species. We have concluded
that the human protein has a region that confers unusual susceptibility to
conversion by CWD prions.
Student Presentations Session 2
The species barriers and public health threat of CWD and BSE prions
Ms. Kristen Davenport1, Dr. Davin Henderson1, Dr. Candace Mathiason1, Dr.
Edward Hoover1 1Colorado State University
Chronic wasting disease (CWD) is spreading rapidly through cervid
populations in the USA. Bovine spongiform encephalopathy (BSE, mad cow disease)
arose in the 1980s because cattle were fed recycled animal protein. These and
other prion diseases are caused by abnormal folding of the normal prion protein
(PrP) into a disease causing form (PrPd), which is pathogenic to nervous system
cells and can cause subsequent PrP to misfold. CWD spreads among cervids very
efficiently, but it has not yet infected humans. On the other hand, BSE was
spread only when cattle consumed infected bovine or ovine tissue, but did
infect humans and other species. The objective of this research is to
understand the role of PrP structure in cross-species infection by CWD and BSE.
To study the propensity of each species’ PrP to be induced to misfold by the
presence of PrPd from verious species, we have used an in vitro system that
permits detection of PrPd in real-time. We measured the conversion efficiency
of various combinations of PrPd seeds and PrP substrate combinations. We
observed the cross-species behavior of CWD and BSE, in addition to
feline-adapted CWD and BSE. We found that CWD adapts to a new host more readily
than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions.
In addition, we investigated the role of specific regions of the bovine, deer and
human PrP protein in resistance to conversion by prions from another species.
We have concluded that the human protein has a region that confers unusual
susceptibility to conversion by CWD prions. CWD is unique among prion diseases
in its rapid spread in natural populations. BSE prions are essentially
unaltered upon passage to a new species, while CWD adapts to the new species.
This adaptation has consequences for surveillance of humans exposed to CWD.
Wildlife Disease Risk Communication Research Contributes to Wildlife Trust
Administration Exploring perceptions about chronic wasting disease risks among
wildlife and agriculture professionals and stakeholders
http://www.wda2016.org/uploads/5/8/6/1/58613359/wda_2016_conference_proceedings_low_res.pdf
PRION 2016 TOKYO
Zoonotic Potential of CWD Prions: An Update
Ignazio Cali1, Liuting Qing1, Jue Yuan1, Shenghai Huang2, Diane Kofskey1,3,
Nicholas Maurer1, Debbie McKenzie4, Jiri Safar1,3,5, Wenquan Zou1,3,5,6,
Pierluigi Gambetti1, Qingzhong Kong1,5,6 1Department of Pathology, 3National
Prion Disease Pathology Surveillance Center, 5Department of Neurology,
6National Center for Regenerative Medicine, Case Western Reserve University,
Cleveland, OH 44106, USA. 4Department of Biological Sciences and Center for
Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta,
Canada, 2Encore Health Resources, 1331 Lamar St, Houston, TX 77010
Chronic wasting disease (CWD) is a widespread and highly transmissible prion
disease in free-ranging and captive cervid species in North America. The
zoonotic potential of CWD prions is a serious public health concern, but the
susceptibility of human CNS and peripheral organs to CWD prions remains largely
unresolved. We reported earlier that peripheral and CNS infections were
detected in transgenic mice expressing human PrP129M or PrP129V. Here we will
present an update on this project, including evidence for strain dependence and
influence of cervid PrP polymorphisms on CWD zoonosis as well as the
characteristics of experimental human CWD prions.
PRION 2016 TOKYO In Conjunction with Asia Pacific Prion Symposium 2016 PRION
2016 Tokyo Prion 2016
http://prion2016.org/dl/newsletter_03.pdf
Cervid to human prion transmission
Kong, Qingzhong
Case Western Reserve University, Cleveland, OH, United States
Abstract
Prion disease is transmissible and invariably fatal. Chronic wasting disease
(CWD) is the prion disease affecting deer, elk and moose, and it is a
widespread and expanding epidemic affecting 22 US States and 2 Canadian
provinces so far. CWD poses the most serious zoonotic prion transmission risks
in North America because of huge venison consumption (>6 million deer/elk
hunted and consumed annually in the USA alone), significant prion infectivity
in muscles and other tissues/fluids from CWD-affected cervids, and usually high
levels of individual exposure to CWD resulting from consumption of the affected
animal among often just family and friends. However, we still do not know
whether CWD prions can infect humans in the brain or peripheral tissues or
whether clinical/asymptomatic CWD zoonosis has already occurred, and we have no
essays to reliably detect CWD infection in humans. We hypothesize that:
(1) The classic CWD prion strain can infect humans at low levels in the brain
and peripheral lymphoid tissues;
(2) The cervid-to-human transmission barrier is dependent on the cervid prion
strain and influenced by the host (human) prion protein (PrP) primary sequence;
(3) Reliable essays can be established to detect CWD infection in humans;and
(4) CWD transmission to humans has already occurred. We will test these
hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in
vitro approaches.
Aim 1 will prove that the classical CWD strain may infect humans in brain or
peripheral lymphoid tissues at low levels by conducting systemic bioassays in a
set of "humanized" Tg mouse lines expressing common human PrP
variants using a number of CWD isolates at varying doses and routes.
Experimental "human CWD" samples will also be generated for Aim 3.
Aim 2 will test the hypothesis that the cervid-to-human prion transmission
barrier is dependent on prion strain and influenced by the host (human) PrP
sequence by examining and comparing the transmission efficiency and phenotypes
of several atypical/unusual CWD isolates/strains as well as a few prion strains
from other species that have adapted to cervid PrP sequence, utilizing the same
panel of humanized Tg mouse lines as in Aim 1.
Aim 3 will establish reliable essays for detection and surveillance of CWD infection
in humans by examining in details the clinical, pathological, biochemical and
in vitro seeding properties of existing and future experimental "human
CWD" samples generated from Aims 1-2 and compare them with those of common
sporadic human Creutzfeldt-Jakob disease (sCJD) prions.
Aim 4 will attempt to detect clinical CWD-affected human cases by examining a
significant number of brain samples from prion-affected human subjects in the
USA and Canada who have consumed venison from CWD-endemic areas utilizing the
criteria and essays established in Aim 3. The findings from this proposal will
greatly advance our understandings on the potential and characteristics of
cervid prion transmission in humans, establish reliable essays for CWD zoonosis
and potentially discover the first case(s) of CWD infection in humans.
Public Health Relevance There are significant and increasing human exposure to
cervid prions because chronic wasting disease (CWD, a widespread and highly
infectious prion disease among deer and elk in North America) continues
spreading and consumption of venison remains popular, but our understanding on
cervid-to-human prion transmission is still very limited, raising public health
concerns. This proposal aims to define the zoonotic risks of cervid prions and
set up and apply essays to detect CWD zoonosis using mouse models and in vitro
methods. The findings will greatly expand our knowledge on the potentials and
characteristics of cervid prion transmission in humans, establish reliable
essays for such infections and may discover the first case(s) of CWD infection
in humans.
Funding Agency Agency National Institute of Health (NIH)
Institute National Institute of Neurological Disorders and Stroke (NINDS)
Type Research Project (R01)
Project # 1R01NS088604-01A1
Application # 9037884
Study Section Cellular and Molecular Biology of Neurodegeneration Study Section
(CMND)
Program Officer Wong, May
Project Start 2015-09-30
Project End 2019-07-31
Budget Start 2015-09-30
Budget End 2016-07-31
Support Year 1
Fiscal Year 2015
Total Cost $337,507
Indirect Cost $118,756
Institution
Name Case Western Reserve University
Department Pathology
Type Schools of Medicine
DUNS # 077758407
City Cleveland
State OH
Country United States
Zip Code 44106
http://grantome.com/grant/NIH/R01-NS088604-01A1
===========================================================
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.
============================================================
Key Molecular Mechanisms of TSEs
Zabel, Mark D.
Colorado State University-Fort Collins, Fort Collins, CO, United States
Abstract Prion diseases, or transmissible spongiform encephalopathies (TSEs),
are fatal neurodegenerative diseases affecting humans, cervids, bovids, and
ovids. The absolute requirement of PrPC expression to generate prion diseases
and the lack of instructional nucleic acid define prions as unique infectious
agents. Prions exhibit species-specific tropism, inferring that unique prion
strains exist that preferentially infct certain host species and confront
transmission barriers to heterologous host species. However, transmission
barriers are not absolute. Scientific consensus agrees that the sheep TSE
scrapie probably breached the transmission barrier to cattle causing bovine
spongiform encephalopathy that subsequently breached the human transmission
barrier and likely caused several hundred deaths by a new-variant form of the
human TSE Creutzfeldt-Jakob disease in the UK and Europe. The impact to human
health, emotion and economies can still be felt in areas like farming, blood
and organ donations and the threat of a latent TSE epidemic. This precedent
raises the real possibility of other TSEs, like chronic wasting disease of
cervids, overcoming similar human transmission barriers. A groundbreaking
discovery made last year revealed that mice infected with heterologous prion
strains facing significant transmission barriers replicated prions far more
readily in spleens than brains6. Furthermore, these splenic prions exhibited
weakened transmission barriers and expanded host ranges compared to neurogenic
prions. These data question conventional wisdom of avoiding neural tissue to
avoid prion xenotransmission, when more promiscuous prions may lurk in
extraneural tissues. Data derived from work previously funded by NIH
demonstrate that Complement receptors CD21/35 bind prions and high density PrPC
and differentially impact prion disease depending on the prion isolate or
strain used. Recent advances in live animal and whole organ imaging have led us
to generate preliminary data to support novel, innovative approaches to
assessing prion capture and transport. We plan to test our unifying hypothesis
for this proposal that CD21/35 control the processes of peripheral prion
capture, transport, strain selection and xenotransmission in the following
specific aims. 1. Assess the role of CD21/35 in splenic prion strain selection
and host range expansion. 2. Determine whether CD21/35 and C1q differentially
bind distinct prion strains 3. Monitor the effects of CD21/35 on prion
trafficking in real time and space 4. Assess the role of CD21/35 in incunabular
prion trafficking
Public Health Relevance Transmissible spongiform encephalopathies, or prion
diseases, are devastating illnesses that greatly impact public health,
agriculture and wildlife in North America and around the world. The impact to
human health, emotion and economies can still be felt in areas like farming,
blood and organ donations and the threat of a latent TSE epidemic. This
precedent raises the real possibility of other TSEs, like chronic wasting
disease (CWD) of cervids, overcoming similar human transmission barriers. Early
this year Canada reported its first case of BSE in over a decade audits first
case of CWD in farmed elk in three years, underscoring the need for continued
vigilance and research. Identifying mechanisms of transmission and zoonoses
remains an extremely important and intense area of research that will benefit
human and other animal populations.
Funding Agency Agency National Institute of Health (NIH)
Institute National Institute of Allergy and Infectious Diseases (NIAID)
Type High Priority, Short Term Project Award (R56)
Project # 1R56AI122273-01A1
Application # 9211114
Study Section Cellular and Molecular Biology of Neurodegeneration Study Section
(CMND)
Program Officer Beisel, Christopher E
Project Start 2016-02-16
Project End 2017-01-31
Budget Start 2016-02-16
Budget End 2017-01-31
Support Year 1
Fiscal Year 2016
Total Cost
Indirect Cost Institution Name Colorado State University-Fort Collins
Department Microbiology/Immun/Virology
Type Schools of Veterinary Medicine
DUNS # 785979618 City Fort Collins
State CO
Country United States
Zip Code 80523
http://grantome.com/grant/NIH/R56-AI122273-01A1
PMCA Detection of CWD Infection in Cervid and Non-Cervid Species
Hoover, Edward Arthur
Colorado State University-Fort Collins, Fort Collins, CO, United States
Abstract Chronic wasting disease (CWD) of deer and elk is an emerging highly
transmissible prion disease now recognized in 18 States, 2 Canadian provinces,
and Korea. We have shown that Infected deer harbor and shed high levels of
infectious prions in saliva, blood, urine, and feces, and in the tissues
generating those body fluids and excreta, thereby leading to facile
transmission by direct contact and environmental contamination. We have also
shown that CWD can infect some non-cervid species, thus the potential risk CWD
represents to domestic animal species and to humans remains unknown. Whether
prions borne in blood, saliva, nasal fluids, milk, or excreta are generated or
modified in the proximate peripheral tissue sites, may differ in subtle ways
from those generated in brain, or may be adapted for mucosal infection remain
open questions. The increasing parallels in the pathogenesis between prion
diseases and human neurodegenerative conditions, such as Alzheimer's and
Parkinson's diseases, add relevance to CWD as a transmissible protein
misfolding disease. The overall goal of this work is to elucidate the process
of CWD prion transmission from mucosal secretory and excretory tissue sites by
addressing these questions: (a) What are the kinetics and magnitude of CWD
prion shedding post-exposure? (b) Are excreted prions biochemically distinct,
or not, from those in the CNS? (c) Are peripheral epithelial or CNS tissues, or
both, the source of excreted prions? and (d) Are excreted prions adapted for
horizontal transmission via natural/trans-mucosal routes? The specific aims of
this proposal are: (1) To determine the onset and consistency of CWD prion
shedding in deer and cervidized mice; (2); To compare the biochemical and
biophysical properties of excretory vs. CNS prions; (3) To determine the
capacity of peripheral tissues to support replication of CWD prions; (4) To
determine the protease- sensitive infectious fraction of excreted vs. CNS
prions; and (5) To compare the mucosal infectivity of excretory vs. CNS prions.
Understanding the mechanisms that enable efficient prion dissemination and
shedding will help elucidate how horizontally transmissible prions evolve and
succeed, and is the basis of this proposal. Understanding how infectious
misfolded proteins (prions) are generated, trafficked, shed, and transmitted
will aid in preventing, treating, and managing the risks associated with these
agents and the diseases they cause.
Public Health Relevance Chronic wasting disease (CWD) of deer and elk is an
emergent highly transmissible prion disease now recognized throughout the USA
as well as in Canada and Korea. We have shown that infected deer harbor and
shed high levels of infectious prions in saliva, blood, urine, and feces
thereby leading to transmission by direct contact and environmental
contamination. In that our studies have also shown that CWD can infect some
non-cervid species, the potential risk CWD may represents to domestic animal
species and humans remains unknown. The increasing parallels in the development
of major human neurodegenerative conditions, such as Alzheimer's and
Parkinson's diseases, and prion diseases add relevance to CWD as a model of a
transmissible protein misfolding disease. Understanding how infectious
misfolded proteins (prions) are generated and transmitted will aid in
interrupting, treating, and managing the risks associated with these agents and
the diseases they cause.
Funding Agency Agency National Institute of Health (NIH)
Institute National Institute of Neurological Disorders and Stroke (NINDS)
Type Research Project (R01)
Project # 4R01NS061902-07
Application # 9010980
Study Section Cellular and Molecular Biology of Neurodegeneration Study Section
(CMND)
Program Officer Wong, May Project Start 2009-09-30
Project End 2018-02-28
Budget Start 2016-03-01
Budget End 2017-02-28
Support Year 7
Fiscal Year 2016
Total Cost $409,868
Indirect Cost $134,234 Institution Name Colorado State University-Fort Collins
Department Microbiology/Immun/Virology
Type Schools of Veterinary Medicine
DUNS # 785979618 City Fort Collins
State CO
Country United States
Zip Code 80523
http://grantome.com/grant/NIH/R01-NS061902-07
LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE
WRONG PLACES $$$
*** These results would seem to suggest that CWD does indeed have zoonotic
potential, at least as judged by the compatibility of CWD prions and their
human PrPC target. Furthermore, extrapolation from this simple in vitro assay
suggests that if zoonotic CWD occurred, it would most likely effect those of
the PRNP codon 129-MM genotype and that the PrPres type would be similar to
that found in the most common subtype of sCJD (MM1).***
https://www.landesbioscience.com/journals/prion/article/28124/?nocache=112223249
Monday, May 02, 2016
*** Zoonotic Potential of CWD Prions: An Update
Prion 2016 Tokyo ***
Saturday, April 23, 2016
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and
zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 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 ef?ciency comparable to that of
cattle BSE. While the ef?ciency 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.
snip...
R. BRADLEY
*** 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.
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.
SCRAPIE WS-01: Prion diseases in animals and
zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl
1933-690X online
Terry S. Singeltary Sr.
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