Herds infected with Chronic Wasting Disease in Canada – 2017
Herds infected with Chronic Wasting Disease in Canada – 2017
The CFIA works with provincial governments and industry to conduct regular Chronic Wasting Disease (CWD) surveillance. Ongoing provincial surveillance for CWD varies with each particular province's perceived threat and infection status. Testing is mandatory in Manitoba, Saskatchewan, Alberta and the Yukon; it is voluntary elsewhere.
In addition, CWD is a reportable disease under the Health of Animals Regulations. This means that all suspected cases must be reported to the CFIA.
Current as of: 2017-02-28
Domestic cervid herds confirmed to be infected with CWD in Canada in 2017
Date confirmed Location Animal type infected
Feb 13 Saskatchewan Elk
CANADA
Herds infected with Chronic Wasting Disease in Canada – 2016 The CFIA works with provincial governments and industry to conduct regular Chronic Wasting Disease (CWD) surveillance. Ongoing provincial surveillance for CWD varies with each particular province's perceived threat and infection status. Testing is mandatory in Manitoba, Saskatchewan, Alberta and the Yukon; it is voluntary elsewhere.
In addition, CWD is a reportable disease under the Health of Animals Regulations. This means that all suspected cases must be reported to the CFIA.
Current as of: 2016-06-30
Domestic cervid herds confirmed to be infected with CWD in Canada in 2016 Date confirmed Location Animal type infected February 18 Saskatchewan Deer March 21 Saskatchewan Deer May 18 Saskatchewan Elk
Additional Information Main page - Chronic wasting disease Federally Reportable Diseases in Canada - 2016 Federally Reportable Diseases in Canada - 2015 Federally Reportable Diseases in Canada - 2014 Federally Reportable Diseases in Canada - 2013
Tuesday, February 10, 2015
Alberta Canada First case of chronic wasting disease found in farm elk since 2002
Saturday, February 14, 2015
Canadian Food Inspection Agency Confirms Bovine Spongiform Encephalopathy (BSE) in Alberta
Monday, April 07, 2014
Saskatchewan’s first chronic wasting disease case of the year has been confirmed 2014
Saturday, October 18, 2014
Chronic wasting disease threatens Canadian agriculture, Alberta MLA says
Wednesday, June 18, 2008
CHRONIC WASTING DISEASE FOUND IN 24 MORE DEER IN ALBERTA
Sunday, May 27, 2012
CANADA PLANS TO IMPRISON ANYONE SPEAKING ABOUT MAD COW or ANY OTHER DISEASE OUTBREAK, CENSORSHIP IS A TERRIBLE THING
KOREA
Saturday, May 28, 2016
*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***
2011-05-23-097 Chronic wasting disease, cervid - Korea ex Canada
To: (06) Transmissible spongiform encephalopathies; (24) Emerging diseases
************************************************* CHRONIC WASTING DISEASE, CERVID - KOREA ex CANADA *************************************************
A ProMED-mail post
Date: 16 May 2011
Source: Prion 2011, Pre-congress Workshop: TSEs in animals and their environment 5 [edited] <http://www.prion2011.ca/files/2011TSEBookletV6Final.pdf>
Chronic Wasting Disease (CWD) outbreaks and surveillance program in the Republic of Korea.
Hyun-Joo Sohn, Yoon-Hee Lee, Min-jeong Kim, Eun-Im Yun, Hyo-Jin Kim, Won-Yong Lee, Dong-Seob Tark, In- Soo Cho.
Foreign Animal Disease Research Division, National Veterinary Research and Quarantine Service, Republic of Korea.
Chronic wasting disease (CWD) has been recognized as an important prion disease in native North American deer and Rocky Mountain elk.
The disease is a unique member of the transmissible spongiform encephalopathies (TSEs), which naturally affects only a few species.
CWD had been limited to USA and Canada until 2000.
On 28 Dec 2000, information from the Canadian government showed that a total of 95 elk had been exported from farms with CWD to Korea.
These consisted of 23 elk in 1994 originating from the so-called "source farm" in Canada and 72 elk in 1997 which had been held in pre-export quarantine at the source farm.
Based on export information of CWD-suspected elk from Canada to Korea, a CWD surveillance program was initiated by the Ministry of Agriculture and Forestry (MAF) in 2001. All elk imported in 1997 were traced back; however, elk imported in 1994 were impossible to identify.
CWD control measures included stamping out of all animals in the affected farm and thorough cleaning and disinfection of the premises.
In addition, nationwide clinical surveillance of Korean native cervids and improved measures to ensure reporting of CWD suspect cases were implemented.
A total of 9 elk were found to be affected. CWD was designated as a notifiable disease under the Act for Prevention of Livestock Epidemics in 2002. Additional CWD cases -- 12 elk and 2 elk -- were diagnosed in 2004 and 2005. Since February 2005, when slaughtered elk were found to be positive, all slaughtered cervids for human consumption at abattoirs were designated as targets of the CWD surveillance program.
Currently, CWD laboratory testing is only conducted by the National Reference Laboratory on CWD, which is the Foreign Animal Disease Division (FADD) of the National Veterinary Research and Quarantine Service (NVRQS).
In July 2010, one out of 3 elk from Farm 1 slaughtered for human consumption were confirmed as positive. Consequently, all cervids -- 54 elk, 41 Sika deer and 5 Albino deer -- were culled, and one elk was found to be positive. Epidemiological investigation was conducted by the Veterinary Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary services.
Epidemiologically-related farms were searched for: 3 farms were found, and all cervids at these farms were culled and subjected to CWD diagnostic [testing]. Three elk and 5 crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2. All cervids at Farm 3 and Farm 4 -- 15 elk and 47 elk -- were culled and confirmed negative.
CENTAUR GLOBAL NETWORK INFORMATION
2
Further epidemiological investigation showed that these CWD outbreaks were linked to the importation of elk from Canada in 1994 based on circumstantial evidence. In December 2010, one elk was confirmed positive at Farm 5.
Consequently, all cervids -- 3 elk, 11 Manchurian Sita deer and 20 Sika deer -- were culled, and one Manchurian Sika deer and 7 Sika deer were found to be positive. This is the 1st report of CWD in these sub-species of deer.
Epidemiological investigation found that the owner of Farm 2 in the CWD outbreaks of July 2010 had co-owned Farm 5. In addition, it was newly revealed that one positive elk was introduced from Farm 6 of Jinju-si Gyeongsang Namdo. All cervids -- 19 elk, 15 crossbreeds (species unknown) and 64 Sika deer -- of Farm 6 were culled, but all were confirmed negative.
--
Communicated by:
Terry S. Singeltary Sr.
[Many of the chronic wasting disease monitoring programs in North America were not in existence in the early 1990s. Most of the North American programs require some type of animal identification and often some corresponding premises identification and accompanying records of births, deaths and testing of naturally deceased and slaughtered animals. It will be interesting to follow the CWD situation in Korea. - Mod.TG]
[see also: 2010
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Chronic wasting disease, cervids - Canada (02): (SK) susp. 20100518.1629 Chronic wasting disease, cervids - Canada: (AB) 20100320.0888
2009
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Chronic wasting disease, cervids - Canada: (SK) 20090417.1462 Chronic wasting disease, cervids - Canada: (AB) 20090327.1192 Chronic wasting disease, cervids - Canada: (AB) 20090131.0444
2008
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Chronic wasting disease, cervids - Canada (03): (SK) 20080819.2590 Chronic wasting disease, cervids - Canada (02): (AB) 20080619.1906 Chronic wasting disease, cervids - Canada (SK): elk 20080517.1647
2007
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Chronic wasting disease, cervids - Canada (04): (SK, NS) 20071027.3497 Chronic wasting disease, cervids - Canada (03): (AB,SK) 20070117.0227 Chronic wasting disease, cervids - Canada (02): (SK) 20070112.0139 Chronic wasting disease, cervids - Canada: (AB) 20070105.0051
2006
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Chronic wasting disease, cervids - Canada (AB) 20060224.0604
2005
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Chronic wasting disease, cervids - Canada (AB) (02) 20051213.3585 Chronic wasting disease, cervids - Canada (AB) 20050907.2650 Chronic wasting disease, cervids - Canada (SK) 20050706.1917
2004
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Chronic wasting disease, cervids - Canada (SK) 20040218.0527 Chronic wasting disease, cervids - Canada (SK) 20040101.0005 CENTAUR GLOBAL NETWORK INFORMATION 3
2003
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Chronic wasting disease, cervids - Canada (SK) (02) 20030314.0633 Chronic wasting disease, cervids - Canada (SK) 20030206.0319 Chronic wasting disease, elk - Canada (SK) 20030115.0123
2002
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Chronic wasting disease, cervids - Canada (Alberta) 20021108.5750 Chronic wasting disease, cervids - Canada (SK) 20021026.5645 Chronic wasting disease, cervids - USA, Canada 20020527.4332 Chronic wasting disease, cervids - Canada 20020401.3858
2001
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Chronic wasting disease, wild deer - Canada (SK) (03) 20010723.1436 Chronic wasting disease, wild deer - Canada (SK) (02) 20010628.1229 Chronic wasting disease, wild deer - Canada (SK) 20010409.06971
1996
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Chronic wasting disease - Canada & USA (2) 19960620.1132 Chronic wasting disease - Canada & USA 19960613.1094 Chronic wasting disease - Canada 19960501.0841]
Between 1996 and 2002, chronic wasting disease was diagnosed in 39 herds of farmed elk in Saskatchewan in a single epidemic. All of these herds were depopulated as part of the Canadian Food Inspection Agency’s (CFIA) disease eradication program. Animals, primarily over 12 mo of age, were tested for the presence CWD prions following euthanasia. Twenty-one of the herds were linked through movements of live animals with latent CWD from a single infected source herd in Saskatchewan, 17 through movements of animals from 7 of the secondarily infected herds.
***The source herd is believed to have become infected via importation of animals from a game farm in South Dakota where CWD was subsequently diagnosed (7,4). A wide range in herd prevalence of CWD at the time of herd depopulation of these herds was observed. Within-herd transmission was observed on some farms, while the disease remained confined to the introduced animals on other farms.
Friday, May 13, 2011
Chronic Wasting Disease (CWD) outbreaks and surveillance program in the Republic of Korea
Hyun-Joo Sohn, Yoon-Hee Lee, Min-jeong Kim, Eun-Im Yun, Hyo-Jin Kim, Won-Yong Lee, Dong-Seob Tark, In- Soo Cho, Foreign Animal Disease Research Division, National Veterinary Research and Quarantine Service, Republic of Korea
Chronic wasting disease (CWD) has been recognized as an important prion disease in native North America deer and Rocky mountain elks. The disease is a unique member of the transmissible spongiform encephalopathies (TSEs), which naturally affects only a few species. CWD had been limited to USA and Canada until 2000.
On 28 December 2000, information from the Canadian government showed that a total of 95 elk had been exported from farms with CWD to Korea. These consisted of 23 elk in 1994 originating from the so-called “source farm” in Canada, and 72 elk in 1997, which had been held in pre export quarantine at the “source farm”.Based on export information of CWD suspected elk from Canada to Korea, CWD surveillance program was initiated by the Ministry of Agriculture and Forestry (MAF) in 2001.
All elks imported in 1997 were traced back, however elks imported in 1994 were impossible to identify. CWD control measures included stamping out of all animals in the affected farm, and thorough cleaning and disinfection of the premises. In addition, nationwide clinical surveillance of Korean native cervids, and improved measures to ensure reporting of CWD suspect cases were implemented.
Total of 9 elks were found to be affected. CWD was designated as a notifiable disease under the Act for Prevention of Livestock Epidemics in 2002.
Additional CWD cases - 12 elks and 2 elks - were diagnosed in 2004 and 2005.
Since February of 2005, when slaughtered elks were found to be positive, all slaughtered cervid for human consumption at abattoirs were designated as target of the CWD surveillance program. Currently, CWD laboratory testing is only conducted by National Reference Laboratory on CWD, which is the Foreign Animal Disease Division (FADD) of National Veterinary Research and Quarantine Service (NVRQS).
In July 2010, one out of 3 elks from Farm 1 which were slaughtered for the human consumption was confirmed as positive. Consequently, all cervid – 54 elks, 41 Sika deer and 5 Albino deer – were culled and one elk was found to be positive. Epidemiological investigations were conducted by Veterinary Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary services.
Epidemiologically related farms were found as 3 farms and all cervid at these farms were culled and subjected to CWD diagnosis. Three elks and 5 crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2.
All cervids at Farm 3 and Farm 4 – 15 elks and 47 elks – were culled and confirmed as negative.
Further epidemiological investigations showed that these CWD outbreaks were linked to the importation of elks from Canada in 1994 based on circumstantial evidences.
In December 2010, one elk was confirmed as positive at Farm 5. Consequently, all cervid – 3 elks, 11 Manchurian Sika deer and 20 Sika deer – were culled and one Manchurian Sika deer and seven Sika deer were found to be positive. This is the first report of CWD in these sub-species of deer. Epidemiological investigations found that the owner of the Farm 2 in CWD outbreaks in July 2010 had co-owned the Farm 5.
In addition, it was newly revealed that one positive elk was introduced from Farm 6 of Jinju-si Gyeongsang Namdo. All cervid – 19 elks, 15 crossbreed (species unknown) and 64 Sika deer – of Farm 6 were culled, but all confirmed as negative.
Saturday, May 28, 2016
*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***
CHRONIC WASTING DISEASE TSE PRION UDATE March 13, 2017
SATURDAY, MARCH 11, 2017
Are Brazilian cervids at risk of prion diseases?
FRIDAY, MARCH 10, 2017
Nebraska Tests confirm spread of CWD to Lancaster County
THURSDAY, MARCH 09, 2017
Missouri MDC REPORTS TWO CASES OF CWD IN ST. CLAIR COUNTY
SATURDAY, MARCH 04, 2017
Maryland DNR Six Deer Test Positive for Chronic Wasting Disease
FRIDAY, JANUARY 27, 2017
TEXAS, Politicians, TAHC, TPWD, and the spread of CWD TSE Prion in Texas
WEDNESDAY, MARCH 01, 2017
Wyoming mule deer test positive for CWD in Cody
WEDNESDAY, MARCH 01, 2017
South central Pennsylvania Captive Deer Tests Positive for Chronic Wasting Disease
THURSDAY, JANUARY 26, 2017
IOWA DNR CONFIRMS 9 CASES CWD from hunter-harvested deer from near Harpers Ferry during the 2016 hunting seasons
MONDAY, JANUARY 23, 2017 North Dakota Two Deer Test Positive for CWD
FRIDAY, JANUARY 20, 2017
Minnesota Chronic Wasting Disease investigation traces exposure to Meeker County farm
FRIDAY, JANUARY 20, 2017
Michigan Chronic wasting disease identified in two Mecosta County farmed deer
SATURDAY, JANUARY 14, 2017
Arkansas Chronic Wasting Disease Reports 158 cases CWD TSE PRION as of January 13, 2017
SATURDAY, JANUARY 14, 2017
CHRONIC WASTING DISEASE CWD TSE PRION GLOBAL UPDATE JANUARY 14, 2017
WEDNESDAY, DECEMBER 21, 2016
TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES 2016 ANNUAL REPORT ARS RESEARCH
cwd resistant cervid???
***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.
P-145 Estimating chronic wasting disease resistance in cervids using real time quaking- induced conversion
Nicholas J Haley1, Rachel Rielinqer2, Kristen A Davenport3, W. David Walter4, Katherine I O'Rourke5, Gordon Mitchell6, Juergen A Richt2
1 Department of Microbiology and Immunology, Midwestern University, United States; 2Department of Diagnostic Medicine and Pathobiology, Kansas State University; 3Prion Research Center; Colorado State University; 4U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit; 5Agricultural Research Service, United States Department of Agriculture; 6Canadian Food Inspection Agency, National and OlE Reference Laboratory for Scrapie and CWO
In mammalian species, the susceptibility to prion diseases is affected, in part, by the sequence of the host's prion protein (PrP). In sheep, a gradation from scrapie susceptible to resistant has been established both in vivo and in vitro based on the amino acids present at PrP positions 136, 154, and 171, which has led to global breeding programs to reduce the prevalence of scrapie in domestic sheep. In cervids, resistance is commonly characterized as a delayed progression of chronic wasting disease (CWD); at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. To model the susceptibility of various naturally-occurring and hypothetical cervid PrP alleles in vitro, we compared the amplification rates and efficiency of various CWD isolates in recombinant PrPC using real time quaking-induced conversion. We hypothesized that amplification metrics of these isolates in cervid PrP substrates would correlate to in vivo susceptibility - allowing susceptibility prediction for alleles found at 10 frequency in nature, and that there would be an additive effect of multiple resistant codons in hypothetical alleles. Our studies demonstrate that in vitro amplification metrics predict in vivo susceptibility, and that alleles with multiple codons, each influencing resistance independently, do not necessarily contribute additively to resistance. Importantly, we found that the white-tailed deer 226K substrate exhibited the slowest amplification rate among those evaluated, suggesting that further investigation of this allele and its resistance in vivo are warranted to determine if absolute resistance to CWD is possible.
***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.
PRION 2016 CONFERENCE TOKYO
Saturday, May 28, 2016
*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***
CHRONIC WASTING DISEASE CWD TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION AKA MAD COW TYPE DISEASE IN CERVID
THE TSE PRION AKA MAD COW TYPE DISEASE IS NOT YOUR NORMAL PATHOGEN.
The TSE prion disease survives ashing to 600 degrees celsius, that’s around 1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat.
you can take the ash and mix it with saline and inject that ash into a mouse, and the mouse will go down with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with.
that’s what’s so worrisome about Iatrogenic mode of transmission, a simple autoclave will not kill this TSE prion agent.
TITLE: PATHOLOGICAL FEATURES OF CHRONIC WASTING DISEASE IN REINDEER AND DEMONSTRATION OF HORIZONTAL TRANSMISSION
*** DECEMBER 2016 CDC EMERGING INFECTIOUS DISEASE JOURNAL CWD HORIZONTAL TRANSMISSION
*** INFECTIOUS AGENT OF SHEEP SCRAPIE MAY PERSIST IN THE ENVIRONMENT FOR AT LEAST 16 YEARS ***
GUDMUNDUR GEORGSSON1, SIGURDUR SIGURDARSON2 AND PAUL BROWN3
Title: Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission
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.
***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.
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.
snip...
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.
snip...
What is the risk of chronic wasting disease being introduced into Great Britain? A Qualitative Risk Assessment October 2012
Thursday, April 07, 2016
What is the risk of chronic wasting disease being introduced into Great Britain? An updated Qualitative Risk Assessment March 2016
Subject: DEFRA What is the risk of a cervid TSE being introduced from Norway into Great Britain? Qualitative Risk Assessment September 2016
Friday, September 30, 2016
DEFRA What is the risk of a cervid TSE being introduced from Norway into Great Britain? Qualitative Risk Assessment September 2016
Scientific Opinion
Chronic wasting disease (CWD) in cervids
Authors
EFSA Panel on Biological Hazards (BIOHAZ),
First published: 18 January 2017Full publication history
DOI: 10.2903/j.efsa.2017.4667View/save citation
Prions in Skeletal Muscles of Deer with Chronic Wasting Disease
Rachel C. Angers1,*, Shawn R. Browning1,*,†, Tanya S. Seward2, Christina J. Sigurdson4,‡, Michael W. Miller5, Edward A. Hoover4, Glenn C. Telling1,2,3,§ snip...
Abstract The emergence of chronic wasting disease (CWD) in deer and elk in an increasingly wide geographic area, as well as the interspecies transmission of bovine spongiform encephalopathy to humans in the form of variant Creutzfeldt Jakob disease, have raised concerns about the zoonotic potential of CWD. Because meat consumption is the most likely means of exposure, it is important to determine whether skeletal muscle of diseased cervids contains prion infectivity.
***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.
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)
snip...
Envt.07:
Pathological Prion Protein (PrPTSE) in Skeletal Muscles of Farmed and Free Ranging White-Tailed Deer Infected with Chronic Wasting Disease
***The presence and seeding activity of PrPTSE in skeletal muscle from CWD-infected cervids suggests prevention of such tissue in the human diet as a precautionary measure for food safety, pending on further clarification of whether CWD may be transmissible to humans.
***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, however, suggests that human susceptibility to CWD is low and there may be a robust species barrier for CWD transmission to humans (Sigurdson, 2008). It is apparent, though, that CWD is affecting wild and farmed cervid populations in endemic areas with some deer populations decreasing as a result.
Technical Abstract:
***Cattle could be exposed to the agent of chronic wasting disease (CWD) through contact with infected farmed or free-ranging cervids or exposure to contaminated premises. The purpose of this study was to assess the potential for CWD derived from elk to transmit to cattle after intracranial inoculation. Calves (n=14) were inoculated with brain homogenate derived from elk with CWD to determine the potential for transmission and define the clinicopathologic features of disease.
Cattle were necropsied if clinical signs occurred or at the termination of experiment (49 months post-inoculation (MPI)).
Clinical signs of poor appetite, weight loss, circling, and bruxism occurred in two cattle (14%) at 16 and 17 MPI, respectively.
Accumulation of abnormal prion protein (PrP**Sc) in these cattle was confined to the central nervous system with the most prominent immunoreactivity in midbrain, brainstem, and hippocampus with lesser immunoreactivity in the cervical spinal cord.
*** The rate of transmission was lower than in cattle inoculated with CWD derived from mule deer (38%) or white-tailed deer (86%).
Additional studies are required to fully assess the potential for cattle to develop CWD through a more natural route of exposure, but a low rate of transmission after intracranial inoculation suggests that risk of transmission through other routes is low.
***A critical finding here is that if CWD did transmit to exposed cattle, currently used diagnostic techniques would detect and differentiate it from other prion diseases in cattle based on absence of spongiform change, distinct pattern of PrP**Sc deposition, and unique molecular profile.
Monday, April 04, 2016
*** Limited amplification of chronic wasting disease prions in the peripheral tissues of intracerebrally inoculated cattle ***
Monday, May 02, 2016
*** Zoonotic Potential of CWD Prions: An Update Prion 2016 Tokyo ***
Exotic Meats USA Announces Urgent Statewide Recall of Elk Tenderloin Because It May Contain Meat Derived From An Elk Confirmed To Have Chronic Wasting Disease
Contact: Exotic Meats USA 1-800-680-4375
FOR IMMEDIATE RELEASE -- February 9, 2009 -- Exotic Meats USA of San Antonio, TX is initiating a voluntary recall of Elk Tenderloin because it may contain meat derived from an elk confirmed to have Chronic Wasting Disease (CWD). The meat with production dates of December 29, 30 and 31, 2008 was purchased from Sierra Meat Company in Reno, NV. The infected elk came from Elk Farm LLC in Pine Island, MN and was among animals slaughtered and processed at USDA facility Noah’s Ark Processors LLC.
Chronic Wasting Disease (CWD) is a fatal brain and nervous system disease found in elk and deer. The disease is caused by an abnormally shaped protein called a prion, which can damage the brain and nerves of animals in the deer family. Currently, it is believed that the prion responsible for causing CWD in deer and elk is not capable of infecting humans who eat deer or elk contaminated with the prion, but the observation of animal-to-human transmission of other prion-mediated diseases, such as bovine spongiform encephalopathy (BSE), has raised a theoretical concern regarding the transmission of CWD from deer or elk to humans. At the present time, FDA believes the risk of becoming ill from eating CWD-positive elk or deer meat is remote. However, FDA strongly advises consumers to return the product to the place of purchase, rather than disposing of it themselves, due to environmental concerns.
Exotic Meats USA purchased 1 case of Elk Tenderloins weighing 16.9 lbs. The Elk Tenderloin was sold from January 16 – 27, 2009. The Elk Tenderloins was packaged in individual vacuum packs weighing approximately 3 pounds each. A total of six packs of the Elk Tenderloins were sold to the public at the Exotic Meats USA retail store. Consumers who still have the Elk Tenderloins should return the product to Exotic Meats USA at 1003 NE Loop 410, San Antonio, TX 78209. Customers with concerns or questions about the Voluntary Elk Recall can call 1-800-680-4375. The safety of our customer has always been and always will be our number one priority.
Exotic Meats USA requests that for those customers who have products with the production dates in question, do not consume or sell them and return them to the point of purchase. Customers should return the product to the vendor. The vendor should return it to the distributor and the distributor should work with the state to decide upon how best to dispose. If the consumer is disposing of the product he/she should consult with the local state EPA office.
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).***
*** 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.
*** 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.
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
Transmission Studies
Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}...TSS
resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.
snip...
Spongiform Encephalopathy in Captive Wild ZOO BSE INQUIRY
”The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite it’s subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA veiwed it as a wildlife problem and consequently not their province!” page 26.
We inoculated cynomolgus macaques with serial dilutions of BSE-infected material. High dose-inoculated animals developed typical clinical disease with all the pathognomonic hallmarks, and incubation periods ranging from 3–8 years. Among low-dosed animals, some developed clinical signs with atypical patterns after extensive incubation periods, exhibiting lesion and biochemical profiles that differed sharply from the typical disease picture. Despite the presence of neurological signs and neuronal lesions, classical lesions of spongiosis and presence of cerebral PrPres were inconstant, or even absent. These observations suggest that low-dose exposure, which would have been the most frequent occurrence during the period of risk, could induce a non-typical pathology that may not be recognized as "prion disease."
link url not available, please see PRION 2011 ;
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
Axis Deer and CWD ?
Many of the regulations or proposed regulations cover only species known to be susceptible to CWD; however, it is not known whether some farmed exotic cervid species in North America, such as fallow deer (Dama dama), sika deer (Cervus nippon), or axis deer (Axis axis), are susceptible to CWD.
WEDNESDAY, NOVEMBER 09, 2016
Norway and Finland Rule Changes for importation and exportation of deer to limit the spread of skrantesjuke (CWD)
Title: Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission
Author item Moore, Sarah item Kunkle, Robert item West greenlee, Mary item Nicholson, Eric item Richt, Juergen item Hamir, Amirali item Waters, Wade item Greenlee, Justin
Submitted to: Emerging Infectious Diseases Publication Type: Peer reviewed journal Publication Acceptance Date: 8/29/2016
Publication Date: N/A
Citation: Interpretive Summary: Chronic wasting disease (CWD) is a fatal neurodegenerative disease that occurs in farmed and wild cervids (deer and elk) of North America and was recently diagnosed in a single free-ranging reindeer (Rangifer tarandus tarandus) in Norway. CWD is a transmissible spongiform encephalopathy (TSE) that is caused by infectious proteins called prions that are resistant to various methods of decontamination and environmental degradation. Little is known about the susceptibility of or potential for transmission amongst reindeer. In this experiment, we tested the susceptibility of reindeer to CWD from various sources (elk, mule deer, or white-tailed deer) after intracranial inoculation and tested the potential for infected reindeer to transmit to non-inoculated animals by co-housing or housing in adjacent pens. Reindeer were susceptible to CWD from elk, mule deer, or white-tailed deer sources after experimental inoculation. Most importantly, non-inoculated reindeer that were co-housed with infected reindeer or housed in pens adjacent to infected reindeer but without the potential for nose-to-nose contact also developed evidence of CWD infection. This is a major new finding that may have a great impact on the recently diagnosed case of CWD in the only remaining free-ranging reindeer population in Europe as our findings imply that horizontal transmission to other reindeer within that herd has already occurred. Further, this information will help regulatory and wildlife officials developing plans to reduce or eliminate CWD and cervid farmers that want to ensure that their herd remains CWD-free, but were previously unsure of the potential for reindeer to transmit CWD.
Technical Abstract: Chronic wasting disease (CWD) is a naturally-occurring, fatal prion disease of cervids. Reindeer (Rangifer tarandus tarandus) are susceptible to CWD following oral challenge, and CWD was recently reported in a free-ranging reindeer of Norway. Potential contact between CWD-affected cervids and Rangifer species that are free-ranging or co-housed on farms presents a potential risk of CWD transmission. The aims of this study were to 1) investigate the transmission of CWD from white-tailed deer (Odocoileus virginianus; CWDwtd), mule deer (Odocoileus hemionus; CWDmd), or elk (Cervus elaphus nelsoni; CWDelk) to reindeer via the intracranial route, and 2) to assess for direct and indirect horizontal transmission to non-inoculated sentinels. Three groups of 5 reindeer fawns were challenged intracranially with CWDwtd, CWDmd, or CWDelk. Two years after challenge of inoculated reindeer, non-inoculated negative control reindeer were introduced into the same pen as the CWDwtd inoculated reindeer (direct contact; n=4) or into a pen adjacent to the CWDmd inoculated reindeer (indirect contact; n=2). Experimentally inoculated reindeer were allowed to develop clinical disease. At death/euthanasia a complete necropsy examination was performed, including immunohistochemical testing of tissues for disease-associated CWD prion protein (PrPcwd). Intracranially challenged reindeer developed clinical disease from 21 months post-inoculation (months PI). PrPcwd was detected in 5 out of 6 sentinel reindeer although only 2 out of 6 developed clinical disease during the study period (< 57 months PI).
***We have shown that reindeer are susceptible to CWD from various cervid sources and can transmit CWD to naïve reindeer both directly and indirectly.
Monday, September 05, 2016
*** Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission Major Findings for Norway ***
Monday, September 05, 2016
Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission Major Findings for Norway
Thursday, September 22, 2016
NORWAY DETECTS 5TH CASE OF CHRONIC WASTING DISEASE CWD TSE PRION Skrantesjuke
SUNDAY, OCTOBER 02, 2016
What is the risk of a cervid TSE being introduced from Norway into Great Britain? Qualitative Risk Assessment September 2016
SATURDAY, OCTOBER 08, 2016
Modeled Impacts of Chronic Wasting Disease on White-Tailed Deer in a Semi-Arid Environment
Terry S. Singeltary Sr.
posted by Terry S. Singeltary Sr. at
2:05 PM
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