Tracking Chronic Wasting Disease in Virginia
Since 2002, over 14,500 deer in Virginia have been tested for Chronic Wasting Disease (CWD). As of April 2019, the Department has diagnosed 68 positive cases of CWD in Virginia since 2009.
CWD Positive Deer in Virginia
2009 1 doe, Frederick Co
2010 1 buck, Frederick Co
2011 1 doe, 1 buck, Frederick Co
2012 1 buck, Frederick Co
2013 1 doe, 1 buck, Frederick Co
2014 2 bucks, Frederick Co; 1 buck, Shenandoah Co
2015 2 bucks, 1 doe, Frederick Co
2016 7 bucks, 2 does, Frederick Co
2017 1 buck, 1 doe, Shenandoah Co; 9 bucks, 5 does, Frederick Co
2018 1 deer, Culpeper Co; 26 deer, Frederick Co; 2 deer, Shenandoah Co
2019 1 deer, Shenandoah Co
As of April 2019, three CWD-positive deer displayed clinical signs of CWD prior to death. These signs included severe emaciation, confusion, lack of fear of humans, and disorientation. Deer infected with CWD can take 18 – 24 months to get sick and exhibit symptoms but may spread the disease to healthy deer even when they do not appear sick.
Below is a summary of CWD Surveillance efforts in Virginia since 2005.
The map below shows the location of Virginia’s CWD-positive deer from 2009 to 2018. During the first few years of Virginia’s CWD outbreak, infected deer were found in a small cluster located very close to the West Virginia state line. Beginning in 2013, CWD-positive deer began to be detected southeast of the established cluster. Since then, the disease has spread along the Virginia-West Virginia state line and also further east across Frederick County. In 2018 CWD was detected for the first time in Culpeper County.
In 2009, the Department established a Containment Area (CA) to help delineate mandatory sampling requirements, liberalized bag limits and seasons, and carcass movement restrictions. The CA was expanded in 2015 to include all of Frederick, Clarke, Shenandoah, and Warren counties.
In 2019, after the detection of CWD in Culpeper County and the subsequent need to create a second CWD response/management area in Virginia, the Department elected to utilize the term CWD Disease Management Area (DMA) instead of CWD Containment Area to delineate affected counties. DMA1 contains the same counties as the current Containment Area (Clarke, Frederick, Shenandoah, and Warren Counties). The borders of CWD DMA2 have not yet been established but will be released to the public well in advance of the 2019 fall hunting season.
For Immediate Release
February 13, 2019
Contact: Dr. Megan Kirchgessner, DGIF Wildlife Veterinarian, 804-837-5666
DGIF REPORTS 28 NEW CWD-POSITIVE WHITE-TAILED DEER
IN NORTHWEST VIRGINIA
RICHMOND- Chronic Wasting Disease (CWD) was confirmed by the Virginia Department of Game and Inland Fisheries (DGIF) in 26 deer from Frederick County and two deer from Shenandoah County during 2018. Twenty-six of the CWD-positive deer were harvested by hunters and showed no symptoms of the disease. Two infected deer were showing signs of the disease prior to death and were reported to the Department by members of the public.
Over 1,550 deer from Frederick, Clarke, Warren, and Shenandoah counties were tested for CWD during the 2018 hunting season. DGIF appreciates the assistance of deer hunters in this area for their excellent cooperation during CWD sample collections this past fall. Additional appreciation is due to road-kill contractors, deer processors, and taxidermists from these four counties who also assisted with CWD sampling this fall. Since 2009, 66 CWD-positive deer have been confirmed from Frederick (61) and Shenandoah (5) counties. All CWD-positive deer have been harvested located west of Interstate 81.
In addition to the sampling effort in Frederick, Clarke, Warren, and Shenandoah counties, DGIF partnered with dozens of taxidermists to enhance CWD surveillance throughout the remainder of Virginia. This partnership proved effective in securing over 1,500 samples from across the state. The results of this effort are currently pending and will be released when they are received from the laboratory.
CWD has been detected in 26 states and three Canadian provinces. The disease is a slow, progressive neurologic (brain and nervous system) disease found in deer, elk, and moose in North America, which ultimately results in death of the animal. It is spread through urine, feces, and saliva. Symptoms do not appear for several years and include staggering, abnormal posture, lowered head, drooling, confusion, and marked weight loss. There is no evidence that CWD can be naturally transmitted to humans, livestock, or pets, but the Centers for Disease Control and Prevention advise hunters to test all deer harvested from known CWD-positive areas and to not consume any animals that test positive for the disease.
Regulations pertaining to CWD, maps of affected states, and more information about the disease and what DGIF is doing about it can be found on the DGIF website at: www.dgif.virginia.gov/wildlife/disease/cwd
# # #
Paige Pearson
Marketing and PR Manager
P 804.593.2051 / M 804.370.0044
Virginia Department of Game & Inland Fisheries
CONSERVE. CONNECT. PROTECT.
A 7870 Villa Park Drive, P.O. Box 90778, Henrico, VA 23228-0778
|
WEDNESDAY, FEBRUARY 13, 2019
Virginia DGIF REPORTS 28 NEW CWD-POSITIVE WHITE-TAILED DEER IN NORTHWEST VIRGINIA
FRIDAY, FEBRUARY 09, 2018
Virginia 2017 Hunt Confirms 16 Cases Chronic Wasting Disease CWD TSE Prion
Sunday, July 17, 2016
Virginia Chronic Wasting Disease CWD As of March 2016 has diagnosed 13 CWD-positive white-tailed deer
WEDNESDAY, JULY 01, 2015
DRAFT Virginia Deer Management Plan 2015-2024 (bans urine scents do to CWD 2015)
Wednesday, February 12, 2014
VIRGINIA VDGIF Reports Two New CWD Positives in Frederick County
Monday, October 08, 2012
VDGIF has discovered four positive cases of CWD in Virginia Updated 9/24/2012
Thursday, March 15, 2012
CWD VIRGINIA TWO NEW CASES
Friday, December 17, 2010
CWD positive in western Frederick County VA VDGIF December 16, 2010
Thursday, January 21, 2010
Chronic Wasting Disease Found in White-tailed Deer in Virginia
cwd tse prion, while rome burns, prepare for the storm
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...
WISCONSIN CWD CAPTIVE CWD UPDATE VIDEO
cwd update on Wisconsin from Tammy Ryan...
FRIDAY, DECEMBER 14, 2018
Wisconsin Hundreds Of Escapes From State Deer Farms Reported Since 2013 December 14, 2018
MONDAY, DECEMBER 10, 2018
Wisconsin DATCP Confirms 11 additional animals from a deer farm in Washington County tested positive for CWD TSE Prion
SSS shoot, shovel, shut the hell up or, let em go, oops, the fence is down again, or another tornado went by, more escapees, reminds me of old Ralph Klein mad cow policy...
SUNDAY, DECEMBER 02, 2018
CWD TSE PRION, REGULATORY LEGISLATION, PAY TO PLAY, and The SPREAD of Chronic Wasting Disease
THURSDAY, MAY 17, 2018
Texas TAHC CWD TSE Prion Pay to Play Federal Indemnity Program, or what i call, ENTITLEMENT PROGRAM for Game Farm Industry
TEXAS BREEDER DEER ESCAPEE WITH CWD IN THE WILD, or so the genetics would show?
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...
SATURDAY, JANUARY 19, 2019
Texas Chronic Wasting Disease CWD TSE Prion Symposium 2018 posted January 2019 VIDEO SET 18 CLIPS
like playing with fire. when you congregate cervid in a given area, by unnatural means, over time, that area and surrounding areas, the soil and surrounding environment become saturated with the CWD TSE Prion.
WEDNESDAY, APRIL 17, 2019
Michigan Senate Bill 37 Sen. Curt VanderWall, R-Ludington to help spread CWD TSE Prion further
SUNDAY, APRIL 14, 2019
Chronic Wasting Disease TSE Prion Strains everything in Texas is bigger, better, and badder
Colorado Chronic Wasting Disease Response Plan December 2018
Not only are the number of infected herds increasing, the past 15 years of disease trends generally show an increase in the proportion of infected animals within herds as well. Of most concern, greater than a 10-fold increase in CWD prevalence has been estimated in some mule deer herds since the early 2000s; CWD is now adversely affecting the performance of these herds.
snip...
(the map on page 71, cwd marked in red, is shocking...tss)
MONDAY, APRIL 15, 2019
Wisconsin 1,060 WTD tested positive for CWD during 2018 surveillance year April 1 through March 31
FRIDAY, APRIL 12, 2019
Sweden Wasting Disease (CWD) discovered on moose in Norrbotten County
FRIDAY, MARCH 29, 2019
First Detection of Chronic Wasting Disease in a Wild Red Deer (Cervus elaphus) in Europe
THURSDAY, MARCH 14, 2019
USDA APHIS CDC Cervids: Chronic Wasting Disease Specifics Updated 2019
SATURDAY, MARCH 16, 2019
Chronic Wasting Disease CWD TSE Prion United States of America Update March 16, 2019
TUESDAY, APRIL 18, 2017
*** EXTREME USA FDA PART 589 TSE PRION FEED LOOP HOLE STILL EXIST, AND PRICE OF POKER GOES UP ***
Friday, December 14, 2012
DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012
snip.....
In the USA, under the Food and Drug Administration's BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system. However, this recommendation is guidance and not a requirement by law.
Animals considered at high risk for CWD include:
1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and
2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal.
Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants.
The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES. It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011.
Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB.
There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products.
snip.....
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.
snip.....
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).
snip.....
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.
snip.....
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.....
i remind Michigan of it's failed mad cow feed ban feed policy;
what is Michigan feeding their cervid ???
2017 Section 21 C.F.R. 589.2000, Animal Proteins Prohibited in Ruminant Feed
Subject: MICHIGAN FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEED VIOLATIONS OFFICIAL ACTION INDICATED OAI UPDATE BREACH APRIL 4, 2017
MICHIGAN FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEEDVIOLATIONS OFFICIAL ACTION INDICATED OAI UPDATE BREACH APRIL 4, 2017
FDA BSE/Ruminant Feed Inspections Firms Inventory
11998 DET-DO MI 48846-847 OPR 4/4/2017 OAI
NAI = NO ACTION INDICATED
OAI = OFFICIAL ACTION INDICATED
VAI = VOLUNTARY ACTION INDICATED
RTS = REFERRED TO STATE
OAI (Official Action Indicated) when inspectors find significant objectionable conditions or practices and believe that regulatory sanctions are warranted to address the establishment’s lack of compliance with the regulation... An example of an OAI classification would be findings of manufacturing procedures insufficient to ensure that ruminant feed is not contaminated with prohibited material. Inspectors will promptly re-inspect facilities classified OAI after regulatory sanctions have been applied to determine whether the corrective actions are adequate to address the objectionable conditions....end...TSS
WEDNESDAY, JULY 11, 2018
CONFIDENTIAL IN CONFIDENCE SPONGIFORM ENCEPHALOPATHY OF PIGS FDA EMERGENCY REQUEST FOR RULE CHANGE USA Section 21 C.F.R. 589.2000
ALABAMA MAD COW FEED IN COMMERCE 2006
RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINE -- CLASS II
______________________________
PRODUCT
a) CO-OP 32% Sinking Catfish, Recall # V-100-6;
b) Performance Sheep Pell W/Decox/A/N, medicated, net wt. 50 lbs, Recall # V-101-6;
c) Pro 40% Swine Conc Meal -- 50 lb, Recall # V-102-6;
d) CO-OP 32% Sinking Catfish Food Medicated, Recall # V-103-6;
e) "Big Jim’s" BBB Deer Ration, Big Buck Blend, Recall # V-104-6;
f) CO-OP 40% Hog Supplement Medicated Pelleted, Tylosin 100 grams/ton, 50 lb. bag, Recall # V-105-6;
g) Pig Starter Pell II, 18% W/MCDX Medicated 282020, Carbadox -- 0.0055%, Recall # V-106-6;
h) CO-OP STARTER-GROWER CRUMBLES, Complete Feed for Chickens from Hatch to 20 Weeks, Medicated, Bacitracin Methylene Disalicylate, 25 and 50 Lbs, Recall # V-107-6;
i) CO-OP LAYING PELLETS, Complete Feed for Laying Chickens, Recall # 108-6;
j) CO-OP LAYING CRUMBLES, Recall # V-109-6;
k) CO-OP QUAIL FLIGHT CONDITIONER MEDICATED, net wt 50 Lbs, Recall # V-110-6;
l) CO-OP QUAIL STARTER MEDICATED, Net Wt. 50 Lbs, Recall # V-111-6;
m) CO-OP QUAIL GROWER MEDICATED, 50 Lbs, Recall # V-112-6
CODE
Product manufactured from 02/01/2005 until 06/06/2006
RECALLING FIRM/MANUFACTURER
Alabama Farmers Cooperative, Inc., Decatur, AL, by telephone, fax, email and visit on June 9, 2006. FDA initiated recall is complete.
REASON
Animal and fish feeds which were possibly contaminated with ruminant based protein not labeled as "Do not feed to ruminants".
VOLUME OF PRODUCT IN COMMERCE
125 tons
DISTRIBUTION
AL and FL
______________________________
PRODUCT
Bulk custom dairy feds manufactured from concentrates, Recall # V-113-6
CODE
All dairy feeds produced between 2/1/05 and 6/16/06 and containing H. J. Baker recalled feed products.
RECALLING FIRM/MANUFACTURER
Vita Plus Corp., Gagetown, MI, by visit beginning on June 21, 2006. Firm initiated recall is complete.
REASON
The feed was manufactured from materials that may have been contaminated with mammalian protein.
VOLUME OF PRODUCT IN COMMERCE
27,694,240 lbs
DISTRIBUTION
MI
______________________________
PRODUCT
Bulk custom made dairy feed, Recall # V-114-6
CODE
None
RECALLING FIRM/MANUFACTURER
Burkmann Feeds LLC, Glasgow, KY, by letter on July 14, 2006. Firm initiated recall is ongoing.
REASON
Custom made feeds contain ingredient called Pro-Lak, which may contain ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
?????
DISTRIBUTION
KY
END OF ENFORCEMENT REPORT FOR AUGUST 2, 2006
###
TUESDAY, APRIL 18, 2017
*** EXTREME USA FDA PART 589 TSE PRION FEED LOOP HOLE STILL EXIST, AND PRICE OF POKER GOES UP ***
***> IMPORTS AND EXPORTS <***
***SEE MASSIVE AMOUNTS OF BANNED ANIMAL PROTEIN AKA MAD COW FEED IN COMMERCE USA DECADES AFTER POST BAN ***
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.
CDC
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
Abstract
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.
SNIP...
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.
***> 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
Abstract
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.
snip...
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
THURSDAY, FEBRUARY 28, 2019
BSE infectivity survives burial for five years with only limited spread
***> CONGRESSIONAL ABSTRACTS PRION CONFERENCE 2018
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
Correspondence
Gudmundur Georgsson ggeorgs@hi.is
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.
TITLE: PATHOLOGICAL FEATURES OF CHRONIC WASTING DISEASE IN REINDEER AND DEMONSTRATION OF HORIZONTAL TRANSMISSION
*** DECEMBER 2016 CDC EMERGING INFECTIOUS DISEASE JOURNAL CWD HORIZONTAL TRANSMISSION
SEE;
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 -
Confidential!!!!
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
PPo4-4:
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 ***
FRIDAY, MARCH 15, 2019
Saskatchewan Chronic Wasting Disease TSE Prion 349 Cases Positive for 2018
TUESDAY, MARCH 26, 2019
USDA ARS 2018 USAHA RESOLUTIONS Investigation of the Role of the Prion Protein Gene in CWD Resistance and Transmission of Disease
WEDNESDAY, APRIL 03, 2019
Estimating the amount of Chronic Wasting Disease infectivity passing through abattoirs and field slaughter
THURSDAY, OCTOBER 04, 2018
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
MONDAY, APRIL 01, 2019
PUBLIC HEALTH U of M launches Chronic Wasting Disease Program to address potential health crisis
> However, to date, no CWD infections have been reported in people.
key word here is ‘reported’. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can’t, and it’s as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it’s being misdiagnosed as sporadic CJD. …terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
Chronic Wasting Disease CWD TSE Prion aka mad deer disease zoonosis
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.
ZOONOTIC CHRONIC WASTING DISEASE CWD TSE PRION UPDATE
here is the latest;
PRION 2018 CONFERENCE
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.
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. <***
READING OVER THE PRION 2018 ABSTRACT BOOK, LOOKS LIKE THEY FOUND THAT from this study ;
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
states.
states.
AND ANOTHER STUDY;
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,
AND
included 104 patients. SEEMS THEY FOUND THAT The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%),
AND
THAT The Majority of cases were male (60%), AND half of them had exposure to wild game.
snip…
see more on Prion 2017 Macaque study from Prion 2017 Conference and other updated science on cwd tse prion zoonosis below…terry
THURSDAY, OCTOBER 04, 2018
Cervid to human prion transmission 5R01NS088604-04 Update
snip…full text;
SATURDAY, FEBRUARY 09, 2019
Experts: Yes, chronic wasting disease in deer is a public health issue — for people
THURSDAY, MARCH 14, 2019
USDA APHIS CDC Cervids: Chronic Wasting Disease Specifics Updated 2019
SATURDAY, MARCH 16, 2019
Chronic Wasting Disease CWD TSE Prion United States of America Update March 16, 2019
FRIDAY, MARCH 15, 2019
Saskatchewan Chronic Wasting Disease TSE Prion 349 Cases Positive for 2018
TUESDAY, MARCH 26, 2019
USDA ARS 2018 USAHA RESOLUTIONS Investigation of the Role of the Prion Protein Gene in CWD Resistance and Transmission of Disease
FRIDAY, MARCH 29, 2019
First Detection of Chronic Wasting Disease in a Wild Red Deer (Cervus elaphus) in Europe
*** 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
WEDNESDAY, SEPTEMBER 08, 2010
CWD PRION CONGRESS SEPTEMBER 8-11 2010
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.
snip....
Prion Infectivity in Fat of Deer with Chronic Wasting Disease▿
Brent Race#, Kimberly Meade-White#, Richard Race and Bruce Chesebro* + Author Affiliations
In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species.
Prions in Skeletal Muscles of Deer with Chronic Wasting Disease
Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure.
*** now, let’s see what the authors said about this casual link, personal communications years ago, and then the latest on the zoonotic potential from CWD to humans from the TOKYO PRION 2016 CONFERENCE.
see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ???? “Our conclusion stating that we found no strong evidence of CWD transmission to humans”
From: TSS (216-119-163-189.ipset45.wt.net)
Subject: CWD aka MAD DEER/ELK TO HUMANS ???
Date: September 30, 2002 at 7:06 am PST
From: "Belay, Ermias"
To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"
Sent: Monday, September 30, 2002 9:22 AM
Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Dear Sir/Madam,
In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091). Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.
Ermias Belay, M.D. Centers for Disease Control and Prevention
-----Original Message-----
From: Sent: Sunday, September 29, 2002 10:15 AM
Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Sunday, November 10, 2002 6:26 PM .......snip........end..............TSS
Thursday, April 03, 2008
A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.
snip...
*** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,
snip... full text ;
> However, to date, no CWD infections have been reported in people.
key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
NOR IS THE FDA recalling this CWD positive elk meat for the well being of the dead elk ;
Wednesday, March 18, 2009
Noah's Ark Holding, LLC, Dawson, MN RECALL Elk products contain meat derived from an elk confirmed to have CWD NV, CA, TX, CO, NY, UT, FL, OK RECALLS AND FIELD CORRECTIONS: FOODS CLASS II
Transmissible Spongiform Encephalopathies
Spongiform Encephalopathy in Captive Wild ZOO BSE INQUIRY
ZOONOSIS OF SCRAPIE TSE PRION
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.
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 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.
snip...
R. BRADLEY
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
Abstract
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.
SNIP...
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.
2002
CHRONIC WASTING DISEASE CONGRESS Serial No. 107-117 May 16, 2002
CHRONIC WASTING DISEASE
JOINT OVERSIGHT HEARING BEFORE THE SUBCOMMITTEE ON FORESTS AND FOREST HEALTH JOINT WITH THE SUBCOMMITTEE ON FISHERIES CONSERVATION, WILDLIFE AND OCEANS OF THE COMMITTEE ON RESOURCES U.S. HOUSE OF REPRESENTATIVES ONE HUNDRED SEVENTH CONGRESS SECOND SESSION
May 16, 2002
Serial No. 107-117
snip...
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.
snip...
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.
WEDNESDAY, FEBRUARY 20, 2019
CHRONIC WASTING DISEASE CONGRESS Serial No. 107-117 May 16, 2002 Updated 2019
MONDAY, FEBRUARY 25, 2019
MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019
BSE INQUIRY EVIDENCE
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:
DEER BRAIN SURVEY
Subject: Re: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY
Date: Fri, 18 Oct 2002 23:12:22 +0100
From: Steve Dealler
Reply-To: Bovine Spongiform Encephalopathy Organization: Netscape Online member
To: BSE-L@ References: <3daf5023 .4080804="" a="" class="yiv1996531157linkified" href="http://wt.net/" rel="noopener noreferrer" style="color: blue; cursor: pointer;" target="_blank">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 ===============
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
https://web.archive.org/web/20090506043931/http://www.bseinquiry.gov.uk/files/yb/1993/12/09001001.pdf
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
FINDINGS
*** 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).
snip...
It was found that when veal was included in the model with another exposure, the association between veal and CJD remained statistically significant (p = < 0.05 for all exposures), while the other exposures ceased to be statistically significant (p = > 0.05).
snip...
In conclusion, an analysis of dietary histories revealed statistical associations between various meats/animal products and INCREASED RISK OF CJD. When some account was taken of possible confounding, the association between VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS STATISTICALLY. ...
snip...
In the study in the USA, a range of foodstuffs were associated with an increased risk of CJD, including liver consumption which was associated with an apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3 studies in relation to this particular dietary factor, the risk of liver consumption became non-significant with an odds ratio of 1.2 (PERSONAL COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (???...TSS)
snip...see full report ;
GAME FARM INDUSTRY WANTS TO COVER UP FINDINGS OF INCREASE RISK TO CJD FROM CERVID
BSE INQUIRY
CJD9/10022
October 1994
Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge Spencers Lane
BerksWell Coventry CV7 7BZ
Dear Mr Elmhirst,
CREUTZFELDT-JAKOB DISEASE (CJD) SURVEILLANCE UNIT REPORT
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;
MONDAY, FEBRUARY 25, 2019
MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019
Terry S. Singeltary Sr.
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