Tuesday, March 26, 2019

USDA ARS 2018 USAHA RESOLUTIONS TWO PRONGED APPROACH NEEDED FOR ADVANCING CATTLE TRACEABILITY

RESOLUTION NUMBER: 34 APPROVED

SOURCE: COMMITTEE ON CATTLE AND BISON

SUBJECT MATTER: TWO PRONGED APPROACH NEEDED FOR ADVANCING CATTLE TRACEABILITY

BACKGROUND INFORMATION:

From the traceability efforts of the Market Cattle Identification (MCI) program focused on the eradication of Brucellosis and Tuberculosis to the United States Animal Identification Plan (USAIP) initiated with the eradication of Brucellosis and phasing out of MCI, to the National Animal Identification System (NAIS) following the finding of Bovine Spongiform Encephalopathy (BSE) and to the current Animal Disease Traceability (ADT) program, traceability of the United States breeding cattle herd has been an ongoing effort framed by state and federal regulations outlining identification and movement documentation requirements. The specific purpose of this program is to allow rapid and accurate traceability of diseased cattle allowing identification, containment and removal of these animals for control purposes or to achieve or maintain disease eradication. A key component to the success of each of these programs is efficiency through full MANDATORY compliance for eligible animals thereby providing pinpoint traces and eliminating unnecessary quarantine testing or depopulation of herds implicated from a broad swath approach.

In parallel, the feeding sector of the United States beef industry has independently pursued VOLUNTARY traceability efforts through private alliances and the United States Department of Agriculture (USDA) Process Verified Programs (PVP) and Quality System Assessment (QSA) value added programs allowing value added marketing to both local and international trade partners.

In 2017, the USDA formed a “State and Federal Working Group” with substantial experience and knowledge of animal disease traceability that “comprehensively reviewed stakeholder feedback and prepared the preliminary” fourteen recommendations for the advancement of animal disease traceability based on the feedback received from the public meetings held in April through July of 2017.

Feedback from stakeholders at these public meetings was very supportive of moving the current MANDATORY ADT program forward with enhancements to make it more efficient, yet it loudly and clearly stated that feeder cattle traceability should remain VOLUNTARY. 

2018 Resolution 34 /page 2

RESOLUTION:

The United States Animal Health Association urges the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service, Veterinary Services to prioritize enhancing the existing mandatory Animal Disease Traceability program based upon the fourteen recommendations made by the State and Federal Working Group, which received feedback from the industry on those proposed directions. USDA should maintain continued support for the voluntary value-added programs and augment opportunities for the feeding sector to enhance trade and marketing. 


BSE, USDA, NAIS, AND TRACEABILITY 

Let's look at how the USDA et al trace BSE aka mad cow cases, birth, and index herd cattle in the past (or rather how they could not trace them).

TEXAS MAD COW (h-BSE), that was finally tested and documented 7+ months after an act of Congress, and Scientist from all over the Globe questioning the testing methods and negative findings of this Texas mad cow. ...

TEXAS h-BSE MAD COW CASE THAT WAS FINALLY DOCUMENTED

***> The animal of interest traced to this herd was classified as untraceable because all leads were exhausted.

this seemed to be the excuse of the day on countless trace efforts of this madcow outbreak in Texas...terry see;

Let's look at how the USDA et al trace BSE aka mad cow cases, birth, and index herd cattle in the past (or rather how they could not trace them).

TEXAS MAD COW (h-BSE), that was finally tested and documented 7+ months after an act of Congress, and Scientist from all over the Globe questioning the testing methods and negative findings of this Texas mad cow. ...

TEXAS h-BSE MAD COW CASE THAT WAS FINALLY DOCUMENTED

Birth Cohort The owner of Farm A kept very few herd records; this made finding documentation on this cow’s birth cohort difficult. The birth cohort, by definition, included all cattle born on the positive animal’s birth premises within 1 year, before or after, the positive animal’s date of birth. The index cow was approximately 12 years of age in November 2004, but there was no exact birth date in the herd records. A potential age range of 11 to 13 years was used to sufficiently cover the animal’s most likely age. Using this range, all cattle born on the index premises between 1990 and 1995 were considered part of the birth cohort. In lieu of the owner’s records, herd records from Veterinary Services’ Generic Database (GDB) were used to compile a list of brucellosis calfhood vaccination (CV) tag numbers from the index herd that corresponded to animals to be included in the birth cohort. There were 121 animals identified through GDB as having been calfhood vaccinated on the index farm between 1991 and 1994. The owner of Farm A did not calfhood vaccinate after 1994. Moreover, calfhood vaccinates include only heifers. Therefore, the list of 121 animals was not a complete list of all birth cohorts. However the tracing that response personnel conducted on other COI was designed to account for the remainder of the birth cohorts.

Feed Cohort ...

SNIP...

Tracing of Progeny

The 2003/2004 progeny of the index cow was known to have left the farm through a specific livestock market sometime between February and October 2004. The 2002/2003 progeny of the index cow left the farm through the same market sometime between January

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and December 2003. Response personnel learned early in the investigation that animals from the index farm were sold not only under the index farm owner’s name and that of his wife, but also by other members of the owner’s immediate family. Additionally, there were no herd records to indicate the gender of the two at-risk progeny. Therefore, market records for February through October 2004 and January through December 2003 were obtained for all calves sold both by Farm A’s owner and by members of his immediate family; response personnel traced all such calves to determine their disposition. With the index herd being composed of mixed breed beef cattle, the calves that left the farm were genetically unsuitable for use as replacement animals or for sale as breeding stock, a fact that was confirmed by the trace work and the documentation of the final disposition of the calves of interest.

Response personnel ultimately identified 213 calves of interest to be traced. Of these, 208 were confirmed to have entered known rendering/slaughter channels, 4 were presumed to have entered rendering/slaughter channels, and 1 was purchased in cash through a livestock market with no buyer name or contact information (this animal was classified as untraceable. See Appendix 1). A calf was categorized as presumed to have entered rendering/slaughter channels if it passed through at least one livestock market subsequent to its original sale and could not be individually traced due to unknown resale date and new backtag, but all calves resold matching that description during an appropriate date range were purchased by known rendering/slaughter order buyers.

It was not possible to DNA test the calves that entered known rendering and slaughter channels – most were of an age in which they were likely to have been slaughtered prior to the time of the investigation. There were no calves traced to farms outside of rendering and slaughter channels.

Tracing of Birth Cohorts

Since there were essentially no records maintained on the index farm, it was necessary to compile the list of known birth cohorts using brucellosis CV tag numbers for this herd from the period 1991 to 1994. The calves vaccinated during that time period were part of the index cow’s birth cohort and tracing activities centered on finding those animals. There were 121 animals whose CV tag number and/or tattoo included them as part of the birth cohort. Of those 121 animals, 67 animals were definitively accounted for (42 were found in the index herd, removed, and tested BSE negative; 25 were identified as having left Farm A through the market system and were traced, 11 of those were reported slaughtered, 13 were classified as presumed dead, and 1 was found alive, euthanized, and tested BSE negative). Of the remaining 54 animals from the birth cohort, there may have been several that died within the index herd, but the majority likely left the herd without identification and would have been either re-tagged at the livestock market or consigned directly to slaughter without identification. To account for these remaining birth cohorts, all adult cattle that left the index farm since 1990 were traced as COI.

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Tracing of Cattle of Interest

The investigation revealed that many animals left Farm A, arrived at markets without any identification tags, and were subsequently re-tagged at the market. Due to lack of farm records, it is unknown which of these re-tagged animals may have belonged to the birth cohort. As a result, all animals that may have left Farm A since 1990 were traced as COI. Additionally, animals from the index farm were sold not only under the index farm owner’s name and that of his wife, but also by other members of the owner’s immediate family; therefore, cattle sold from the index farm by all pertinent family members were traced. There were some older animals that left the index farm but were able to be excluded from further trace work because they were known not to have been part of the birth cohort or feed cohort of the index cow despite their being of the appropriate age. The index farm owner’s late father had maintained a herd of cattle separate from the index farm but which was added to the index farm in 1997. Complete herd test data and CV data from the GDB was obtained for the father’s herd and those animals were excluded from the tracing activities.

There were a total of 200 COI traced: 143 were reported to have been slaughtered (131 of those were confirmed as having been slaughtered), 1 is known to have died previously and was buried, 2 were found alive (1 was a known birth cohort that tested negative, 1 was determined not to be one of the cattle of interest due to her young age), 34 were classified as presumed dead, 20 were classified as untraceable. (See Appendix 1). Animals were confirmed at slaughter using GDB slaughter testing data or the hard copies of slaughter testing Form 4-54.

An animal was classified as presumed dead if records that could be used to advance the tracing of the animal were exhausted or did not exist, and the age of the animal at the time of the investigation was estimated to be at least 11 years old or older. Since the index herd was not a purebred or seedstock operation, and animals leaving the herd were unlikely to be purchased as replacement cattle, standard industry practices indicated that most adult animals that had left the herd would have been culled and slaughtered by the time they were in this age group. Additionally, this age cutoff was arrived at through review of market records and the specific years in which Farm A sold cattle through the market. An animal was classified as untraceable if all records to advance the tracing of the animal were exhausted or did not exist, and the age of the animal at the time of the investigation was estimated to be less than 11 years of age (the animal, therefore, could not be presumed dead).

snip...

Trace Herd 1

The owner of Trace Herd 1 was identified as having received one of the adult COI from the index herd. Trace Herd 1 contained 909 head of cattle in multiple pastures and was placed under hold order on 7/21/05. Upon completion of herd inventory, the animal of interest was not found within the herd. A GDB search of all recorded herd tests conducted on Trace Herd 1 and all market sales by the owner failed to locate the identification tag of the animal of interest and she was subsequently classified as untraceable. The hold order on Trace Herd 1 was released on 8/8/05.

Trace Herd 2

Trace Herd 2 was identified as having received one of the adult COI from the index herd. Trace Herd 2 contained 19 head of cattle on one pasture and was placed under hold order on 7/25/05. The owner of Trace Herd 2 identified the animal of interest by her eartag while he was feeding his cattle out of a bucket and individually penned her for inspection by field personnel. While the cow was identified as one of the animals that had left the index farm, her age by dentition was estimated to be only 5 years old, which was too young to have placed her as part of the birth or feed cohort of the index animal. She was classified as found alive but determined not to be one of the COI; the hold order on Trace Herd 2 was released on 7/26/05.

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Trace Herd 3

The owner of Trace Herd 3 was identified as possibly having received an animal of interest. The herd was placed under hold order on 7/27/05. The herd inventory was conducted on 7/28/05. The animal of interest was not present within the herd, and the hold order was released on 7/28/05. The person who thought he sold the animal to the owner of Trace Herd 3 had no records and could not remember who else he might have sold the cow to. Additionally, a search of GDB for all cattle sold through the markets by that individual did not result in a match to the animal of interest. The animal of interest traced to this herd was classified as untraceable because all leads were exhausted.

Trace Herd 4

The owner of Trace Herd 4 was identified as having received one of the COI through an order buyer. Trace Herd 4 was placed under hold order on 7/29/05. A complete herd inventory was conducted on 8/22/05 and 8/23/05. There were 233 head of cattle that were examined individually by both State and Federal personnel for all man-made identification and brands. The animal of interest was not present within the herd. Several animals were reported to have died in the herd sometime after they arrived on the premises in April 2005. A final search of GDB records yielded no further results on the eartag of interest at either subsequent market sale or slaughter. With all leads having been exhausted, this animal of interest has been classified as untraceable. The hold order on Trace Herd 4 was released on 8/23/05.

Trace Herd 5

The owner of Trace Herd 5 was identified as having received two COI and was placed under hold order on 8/1/05. Trace Herd 5 is made up of 67 head of cattle in multiple pastures. During the course of the herd inventory, the owner located records that indicated that one of the COI, a known birth cohort, had been sold to Trace Herd 8 where she was subsequently found alive. Upon completion of the herd inventory, the other animal of interest was not found within the herd. A GDB search of all recorded herd tests conducted on Trace Herd 5 and all market sales by the owner failed to locate the identification tag of the animal of interest and she was subsequently classified as untraceable due to all leads having been exhausted. The hold order on Trace Herd 5 was released on 8/8/05.

Trace Herd 6

The owner of Trace Herd 6 was identified as possibly having received an animal of interest and was placed under hold order on 8/1/05. This herd is made up of 58 head of cattle on two pastures. A herd inventory was conducted and the animal of interest was not present within the herd. The owner of Trace Herd 6 had very limited records and was unable to provide further information on where the cow might have gone after he purchased her from the livestock market. A search of GDB for all cattle sold through the markets by that individual did not result in a match to the animal of interest. Additionally, many of the animals presented for sale by the owner of the herd had been re-tagged at the market effectually losing the traceability of the history of that animal prior to re-tagging. The animal of interest traced to this herd was classified as untraceable due to all leads having been exhausted. The hold order on Trace Herd 6 was released on 8/3/05.

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Trace Herd 7

The owner of Trace Herd 7 was identified as having received an animal of interest and was placed under hold order on 8/1/05. Trace Herd 7 contains 487 head of cattle on multiple pastures in multiple parts of the State, including a unit kept on an island. The island location is a particularly rough place to keep cattle and the owner claimed to have lost 22 head on the island in 2004 due to liver flukes. Upon completion of the herd inventory, the animal of interest was not found present within Trace Herd 7. A GDB search of all recorded herd tests conducted on Trace Herd 7 and all market sales by the owner failed to locate the identification tag of the animal of interest. The cow was subsequently classified as untraceable. It is quite possible though that she may have died within the herd, especially if she belonged to the island unit. The hold order on Trace Herd 7 was released on 8/8/05.

Trace Herd 8

Trace Herd 8 received an animal of interest, which happened to be a known birth cohort of the index cow, from Trace Herd 5. Trace Herd 8 consists of 146 head of cattle that were placed under hold order on 8/4/05. A herd inventory was conducted, the birth cohort was found alive in the herd, and she was purchased and euthanized. The hold order on Trace Herd 8 was released on 8/4/05. The cow was sampled on 8/5/05 and BSE tested by ELISA at NVSL. Results were negative (as reported on 8/6/05); carcass disposal was completed by alkaline digestion.

Analysis of Data on Presumed Dead and Untraceable Animals

CEAH performed an analysis of the minimum estimated ages of those COI that were classified as either presumed dead or untraceable to determine the likely disposition of those animals based on their ages. Moreover, CEAH performed an analysis of the likely disposition of the one calf that was classified as untraceable during the investigation.


http://www.aphis.usda.gov/newsroom/hot_issues/bse/downloads/bse_final_epi_report8-05.pdf


http://usdameatexport.blogspot.com/2009/03/nais-comments-ncba-and-r-calf-wednesday.html


OF course, the birth and herd cohorts of this highly suspect, stumbling and staggering mad cow in Texas, will never be known ;


FOR IMMEDIATE RELEASE Statement May 4, 2004 Media Inquiries: 301-827-6242 Consumer Inquiries: 888-INFO-FDA

Statement on Texas Cow With Central Nervous System Symptoms

On Friday, April 30 th , the Food and Drug Administration learned that a cow with central nervous system symptoms had been killed and shipped to a processor for rendering into animal protein for use in animal feed.

FDA, which is responsible for the safety of animal feed, immediately began an investigation. On Friday and throughout the weekend, FDA investigators inspected the slaughterhouse, the rendering facility, the farm where the animal came from, and the processor that initially received the cow from the slaughterhouse.

FDA's investigation showed that the animal in question had already been rendered into "meat and bone meal" (a type of protein animal feed). Over the weekend FDA was able to track down all the implicated material. That material is being held by the firm, which is cooperating fully with FDA.

Cattle with central nervous system symptoms are of particular interest because cattle with bovine spongiform encephalopathy or BSE, also known as "mad cow disease," can exhibit such symptoms. In this case, there is no way now to test for BSE. But even if the cow had BSE, FDA's animal feed rule would prohibit the feeding of its rendered protein to other ruminant animals (e.g., cows, goats, sheep, bison).

FDA is sending a letter to the firm summarizing its findings and informing the firm that FDA will not object to use of this material in swine feed only. If it is not used in swine feed, this material will be destroyed. Pigs have been shown not to be susceptible to BSE. If the firm agrees to use the material for swine feed only, FDA will track the material all the way through the supply chain from the processor to the farm to ensure that the feed is properly monitored and used only as feed for pigs.

To protect the U.S. against BSE, FDA works to keep certain mammalian protein out of animal feed for cattle and other ruminant animals. FDA established its animal feed rule in 1997 after the BSE epidemic in the U.K. showed that the disease spreads by feeding infected ruminant protein to cattle.

Under the current regulation, the material from this Texas cow is not allowed in feed for cattle or other ruminant animals. FDA's action specifying that the material go only into swine feed means also that it will not be fed to poultry.

FDA is committed to protecting the U.S. from BSE and collaborates closely with the U.S. Department of Agriculture on all BSE issues. The animal feed rule provides crucial protection against the spread of BSE, but it is only one of several such firewalls. FDA will soon be improving the animal feed rule, to make this strong system even stronger.

####

http://www.fda.gov/bbs/topics/news/2004/new01061.html


BSE UPDATE ALABAMA March 17, 2006

BSE Update From Alabama

News Date March 27, 2006

Alabama Agriculture Commissioner Ron Sparks and Alabama State Veterinarian Dr. Tony Frazier with the Alabama Department of Agriculture and Industries (ADAI) and USDA have provided an update on their ongoing joint investigation of the cow that died from bovine spongiform encephalopathy (BSE) in Alabama.

Since the investigation began, the ADAI and the USDA have followed multiple leads in the traceback process. At this time, 13 locations and 32 movements of cattle have been examined with 27 of those being substantially completed. Additional investigations of locations and herds will continue. In addition, state and federal officials have confirmed that a black bull calf was born in 2005 to the index animal (the red cow). The calf was taken by the owner to a local stockyard in July 2005 where the calf died. The calf was disposed of in a local landfill and did not enter the human or animal food chain.

Without a premises or animal ID program in place, the traceback process to find the herd of origin of the index cow is time-consuming and difficult. It includes conducting interviews, reviewing of records and documents, and testing of cattle DNA. State and federal officials have discovered several herds of interest and they are planning to use DNA testing to determine DNA linkage between the index cow and the herds. Through the DNA testing of these herds, investigators will attempt to find a genetic path that could lead to the herd of origin. Sparks stressed that the DNA testing being conducted on the herds is for genetic markers and is not a test for the disease BSE.

As part of the thorough investigative process, a large number of cattle may be tested in this phase and the number of herds included will continue to grow as the traceback progresses. Leads will be followed by state and federal officials until they are exhausted. Even when an index animal is traced to its birth herd, often cohorts of that animal are no longer in that herd. In addition, even if an animal's cohort has been exposed to the same infective material in feed, the other animals will not necessarily contract BSE.

BSE is not a contagious disease that spreads animal to animal, or animal to human. BSE spreads in cattle through the consumption of feed containing specified risk material (brain and spinal cord) derived from BSE infected cattle. The United States banned the use of such protein supplements in cattle feed since 1997. Sparks says that beef consumption in this country is safe and there are measures in place to see that it continues to be safe. For example, downer animals are not allowed to enter commerce for human consumption and there is a ban on feeding ruminant derived protein to cattle. (Contact: Bob Ehart)

News Contact: Bob Ehart; 202-296-9680

http://www.nasda.org/cms/7196/7347/10354.aspx



WELL, we know that the FDA mad cow feed ban of August 4, 1997 was nothing but ink on paper. there is still animal protein in commerce in the USA being fed out to cattle and other livestock as we speak. see a few warning letters and or recalls here ;

http://madcowfeed.blogspot.com/2010/02/import-alert-99-25-detention-without.html


WE also know that the USDA certified dead stock downer cow school lunch program NSLP, fed these most high risk cattle for BSE and mad cow disease and other deadly pathogens to our children all across our Nation for over 4 YEARS, you can see this here ;


http://downercattle.blogspot.com/2009/09/suit-meatpacker-used-downer-cows-for-4.html


AND there is evidence of cohort BSE documented (see at bottom) ;

Alabama BSE Investigation Final Epidemiology Report May 2, 2006


http://www.aphis.usda.gov/newsroom/hot_issues/bse/downloads/EPI_Final5-2-06.pdf


THURSDAY, JULY 28, 2011


An Update on the Animal Disease Traceability Framework July 27, 2011


FRIDAY, AUGUST 20, 2010

USDA: Animal Disease Traceability August 2010


USDA: Animal Disease Traceability August 2010

http://naiscoolyes.blogspot.com/2010/08/usda-animal-disease-traceability-august.html


PRION 2018 CONFERENCE ABSTRACT;

READING OVER THE Prion 2018 Book of Absracts, seems they found that;

O10 Zoonotic potential of atypical BSE prions: a systematic evaluation 

Marín-Moreno A (1), Espinosa JC (1), Douet JY (2), Aguilar-Calvo P (1), Píquer J (1), Lorenzo P (1), Lacroux C (2), Huor A (2), Lugan S (2), Tillier C (2), Andreoletti O (2) and Juan María Torres (1) 

Our results confirm that L-BSE transmits to TgMet129 even better than epidemic BSE. However, atypical L-BSE agent was unable to infect TgVal129 or TgMet/Val129 mice, even after passage in TgMet129. No transmission was observed with H-BSE in any mice model inoculated, irrespectively of the 129 polymorphism. 

***>After passage in sheep PrP expressing host, the properties of both H and LBSE including their capacity to cross the human species barrier were dramatically affected, emerging prion strains features that resemble those of sporadic Creutzfeldt-Jakob disease (sCJD). To date, this is the more extensive and complete analysis of the zoonotic potential of atypical BSE prions. 

***>These results advise not to ignore the zoonotic potential of these agents.

also, another study;

P77 In vitro approach to estimate the human transmission risk of prions

Iwamaru Y (1) Imamura M (2) Matsuura Y (1) Kohtaro Miyazawa (1) Takashi Yokoyama (3) (1 ) National Institute of Animal Health, Prion Disease Unit, Ibaraki, Japan (2) University of Miyazaki, Division of Microbiology, Miyazaki, Japan (3) National Institute of Animal Health, Department of Planning and General Administration, Ibaraki, Japan.

snip...

In attempt to develop the more time- and cost-saving method for assessment of the human transmission risk of prions, we performed experiments using protein misfolding cyclic amplification (PMCA) technique to investigate whether PMCA can be compatible with bioassay. Using brain homogenates of Tg expressing bovine PrP as the PrP substrate, we optimized the versatile PMCA condition that could amplify PrPSc from cattle affected with C-, H- or L-BSE. 

***>We measured the 50% PMCA seeding activity dose and the 50% lethal dose in 1 g equivalent of C-, H- or L-BSE cattle brain tissue by using PMCA or bioassay, respectively, and assessed the correlations between these doses.

and also this study;

P98 The agent of H-type bovine spongiform encephalopathy associated with E211K prion protein polymorphism transmits after oronasal challenge

Greenlee JJ (1), Moore SJ (1), and West Greenlee MH (2)

This study demonstrates that the H-type BSE agent is transmissible by the oronasal route. These results reinforce the need for ongoing surveillance for classical and atypical BSE to minimize the risk of potentially infectious tissues entering the animal or human food chains.


Sunday, February 25, 2018

PRION ROUND TABLE CONFERENCE 2018 MAY, 22-25 A REVIEW


sadly, i remember trying to tell them this long ago;

2009 UPDATE ON ALABAMA AND TEXAS MAD COWS 2005 and 2006 


LET'S take a closer look at this new prionpathy or prionopathy, and then let's look at the g-h-BSEalabama mad cow. 

This new prionopathy in humans? 

the genetic makeup is IDENTICAL to the g-h-BSEalabama mad cow, the only _documented_ mad cow in the world to date like this, ......

wait, it get's better. this new prionpathy is killing young and old humans, with LONG DURATION from onset of symptoms to death, and the symptoms are very similar to nvCJD victims, OH, and the plaques are very similar in some cases too, bbbut, it's not related to the g-h-BSEalabama cow, 

WAIT NOW, it gets even better, the new human prionpathy that they claim is a genetic TSE, has no relation to any gene mutation in that family. daaa, ya think it could be related to that mad cow with the same genetic make-up ??? 

there were literally tons and tons of banned mad cow protein in Alabama in commerce, and none of it transmitted to cows, and the cows to humans there from ??? r i g h t $$$ 

ALABAMA MAD COW g-h-BSEalabama 

In this study, we identified a novel mutation in the bovine prion protein gene (Prnp), called E211K, of a confirmed BSE positive cow from Alabama, United States of America. 

This mutation is identical to the E200K pathogenic mutation found in humans with a genetic form of CJD. 

This finding represents the first report of a confirmed case of BSE with a potential pathogenic mutation within the bovine Prnp gene. 

We hypothesize that the bovine Prnp E211K mutation most likely has caused BSE in "the approximately 10-year-old cow" carrying the E221K mutation. 



Saturday, August 14, 2010 

BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and VPSPr PRIONPATHY (see mad cow feed in COMMERCE IN ALABAMA...TSS) 


her healthy calf also carried the mutation (J. A. Richt and S. M. Hall PLoS Pathog. 4, e1000156; 2008). This raises the possibility that the disease could occasionally be genetic in origin. Indeed, the report of the UK BSE Inquiry in 2000 suggested that the UK epidemic had most likely originated from such a mutation and argued against the scrapierelated assumption. Such rare potential pathogenic PRNP mutations could occur in countries at present considered to be free of BSE, such as Australia and New Zealand. So it is important to maintain strict surveillance for BSE in cattle, with rigorous enforcement of the ruminant feed ban (many countries still feed ruminant proteins to pigs). Removal of specified risk material, such as brain and spinal cord, from cattle at slaughter prevents infected material from entering the human food chain. Routine genetic screening of cattle for PRNP mutations, which is now available, could provide additional data on the risk to the public. Because the point mutation identified in the Alabama animals is identical to that responsible for the commonest type of familial (genetic) CJD in humans, it is possible that the resulting infective prion protein might cross the bovine-human species barrier more easily. Patients with vCJD continue to be identified. The fact that this is happening less often should not lead to relaxation of the controls necessary to prevent future outbreaks. Malcolm A. Ferguson-Smith Cambridge University Department of Veterinary Medicine, Madingley Road, Cambridge CB3 0ES, UK e-mail: maf12@cam.ac.uk Jürgen A. Richt College of Veterinary Medicine, Kansas State University, K224B Mosier Hall, Manhattan, Kansas 66506-5601, USA NATURE|Vol 457|26 February 2009


Thursday, July 24, 2014 

*** Protocol for further laboratory investigations into the distribution of infectivity of Atypical BSE SCIENTIFIC REPORT OF EFSA New protocol for Atypical BSE investigations 


snip...see full text ;


Saturday, August 14, 2010

BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and VPSPr PRIONPATHY


FRIDAY, AUGUST 10, 2018 

From Gate to Plate, BSE aka mad cow disease, USDA, NAIS, AND TRACEABILITY


TUESDAY, AUGUST 28, 2018 

USDA finds BSE infection in Florida cow 08/28/18 6:43 PM



WEDNESDAY, AUGUST 29, 2018 

USDA Announces Atypical Bovine Spongiform Encephalopathy Detection USDA 08/29/2018 10:00 AM EDT



WEDNESDAY, AUGUST 29, 2018 

Transmissible Spongiform Encephalopathy TSE Prion Atypical BSE Confirmed Florida Update USA August 28, 2018



***> P.108: Successful oral challenge of adult cattle with classical BSE

Sandor Dudas1,*, Kristina Santiago-Mateo1, Tammy Pickles1, Catherine Graham2, and Stefanie Czub1 1Canadian Food Inspection Agency; NCAD Lethbridge; Lethbridge, Alberta, Canada; 2Nova Scotia Department of Agriculture; Pathology Laboratory; Truro, Nova Scotia, Canada

Classical Bovine spongiform encephalopathy (C-type BSE) is a feed- and food-borne fatal neurological disease which can be orally transmitted to cattle and humans. Due to the presence of contaminated milk replacer, it is generally assumed that cattle become infected early in life as calves and then succumb to disease as adults. Here we challenged three 14 months old cattle per-orally with 100 grams of C-type BSE brain to investigate age-related susceptibility or resistance. During incubation, the animals were sampled monthly for blood and feces and subjected to standardized testing to identify changes related to neurological disease. At 53 months post exposure, progressive signs of central nervous system disease were observed in these 3 animals, and they were euthanized. Two of the C-BSE animals tested strongly positive using standard BSE rapid tests, however in 1 C-type challenged animal, Prion 2015 Poster Abstracts S67 PrPsc was not detected using rapid tests for BSE. Subsequent testing resulted in the detection of pathologic lesion in unusual brain location and PrPsc detection by PMCA only. 

***Our study demonstrates susceptibility of adult cattle to oral transmission of classical BSE. 

We are further examining explanations for the unusual disease presentation in the third challenged animal.



***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.

P.86: Estimating the risk of transmission of BSE and scrapie to ruminants and humans by protein misfolding cyclic amplification

Morikazu Imamura, Naoko Tabeta, Yoshifumi Iwamaru, and Yuichi Murayama

National Institute of Animal Health; Tsukuba, Japan

To assess the risk of the transmission of ruminant prions to ruminants and humans at the molecular level, we investigated the ability of abnormal prion protein (PrPSc) of typical and atypical BSEs (L-type and H-type) and typical scrapie to convert normal prion protein (PrPC) from bovine, ovine, and human to proteinase K-resistant PrPSc-like form (PrPres) using serial protein misfolding cyclic amplification (PMCA).

Six rounds of serial PMCA was performed using 10% brain homogenates from transgenic mice expressing bovine, ovine or human PrPC in combination with PrPSc seed from typical and atypical BSE- or typical scrapie-infected brain homogenates from native host species. In the conventional PMCA, the conversion of PrPC to PrPres was observed only when the species of PrPC source and PrPSc seed matched. However, in the PMCA with supplements (digitonin, synthetic polyA and heparin), both bovine and ovine PrPC were converted by PrPSc from all tested prion strains. On the other hand, human PrPC was converted by PrPSc from typical and H-type BSE in this PMCA condition.

Although these results were not compatible with the previous reports describing the lack of transmissibility of H-type BSE to ovine and human transgenic mice, 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.



P.170: Potential detection of oral transmission of H type atypical BSE in cattle using in vitro conversion

***P.170: Potential detection of oral transmission of H type atypical BSE in cattle using in vitro conversion

Sandor Dudas, John G Gray, Renee Clark, and Stefanie Czub Canadian Food Inspection Agency; Lethbridge, AB Canada

Keywords: Atypical BSE, oral transmission, RT-QuIC

The detection of bovine spongiform encephalopathy (BSE) has had a significant negative impact on the cattle industry worldwide. In response, governments took actions to prevent transmission and additional threats to animal health and food safety. While these measures seem to be effective for controlling classical BSE, the more recently discovered atypical BSE has presented a new challenge. To generate data for risk assessment and control measures, we have challenged cattle orally with atypical BSE to determine transmissibility and mis-folded prion (PrPSc) tissue distribution. Upon presentation of clinical symptoms, animals were euthanized and tested for characteristic histopathological changes as well as PrPSc deposition.

The H-type challenged animal displayed vacuolation exclusively in rostral brain areas but the L-type challenged animal showed no evidence thereof. To our surprise, neither of the animals euthanized, which were displaying clinical signs indicative of BSE, showed conclusive mis-folded prion accumulation in the brain or gut using standard molecular or immunohistochemical assays. To confirm presence or absence of prion infectivity, we employed an optimized real-time quaking induced conversion (RT-QuIC) assay developed at the Rocky Mountain Laboratory, Hamilton, USA.

Detection of PrPSc was unsuccessful for brain samples tests from the orally inoculated L type animal using the RT-QuIC. It is possible that these negative results were related to the tissue sampling locations or that type specific optimization is needed to detect PrPSc in this animal. We were however able to consistently detect the presence of mis-folded prions in the brain of the H-type inoculated animal. Considering the negative and inconclusive results with other PrPSc detection methods, positive results using the optimized RT-QuIC suggests the method is extremely sensitive for H-type BSE detection. This may be evidence of the first successful oral transmission of H type atypical BSE in cattle and additional investigation of samples from these animals are ongoing.






Detection of PrPBSE and prion infectivity in the ileal Peyer’s patch of young calves as early as 2 months after oral challenge with classical bovine spongiform encephalopathy 

Ivett Ackermann1 , Anne Balkema‑Buschmann1 , Reiner Ulrich2 , Kerstin Tauscher2 , James C. Shawulu1 , Markus Keller1 , Olanrewaju I. Fatola1 , Paul Brown3 and Martin H. Groschup1* 

Abstract 

In classical bovine spongiform encephalopathy (C-BSE), an orally acquired prion disease of cattle, the ileal Peyer’s patch (IPP) represents the main entry port for the BSE agent. In earlier C-BSE pathogenesis studies, cattle at 4–6 months of age were orally challenged, while there are strong indications that the risk of infection is highest in young animals. In the present study, unweaned calves aged 4–6 weeks were orally challenged to determine the earli‑ est time point at which newly formed PrPBSE and BSE infectivity are detectable in the IPP. For this purpose, calves were culled 1 week as well as 2, 4, 6 and 8 months post-infection (mpi) and IPPs were examined for BSE infectivity using a bovine PrP transgenic mouse bioassay, and for PrPBSE by immunohistochemistry (IHC) and protein misfolding cyclic amplifcation (PMCA) assays. For the frst time, BSE prions were detected in the IPP as early as 2 mpi by transgenic mouse bioassay and PMCA and 4 mpi by IHC in the follicular dendritic cells (FDCs) of the IPP follicles. These data indi‑ cate that BSE prions propagate in the IPP of unweaned calves within 2 months of oral uptake of the agent.

In summary, our study demonstrates for the frst time PrPBSE (by PMCA) and prion infectivity (by mouse bioassay) in the ileal Peyer’s patch (IPP) of young calves as early as 2 months after infection. From 4 mpi nearly all calves showed PrPBSE positive IPP follicles (by IHC), even with PrPBSE accumulation detectable in FDCs in some animals. Finally, our results confrm the IPP as the early port of entry for the BSE agent and a site of initial propagation of PrPBSE and infectivity during the early pathogenesis of the disease. Terefore, our study supports the recommendation to remove the last four metres of the small intestine (distal ileum) at slaughter, as designated by current legal requirements for countries with a controlled BSE risk status, as an essential measure for consumer and public health protection.



A study comparing preclinical cattle infected naturally with BSE to clinically affected cattle either naturally or experimentally infected with BSE by the oral route found the most abundant PrPSc in the brainstem area (39), which is consistent with ascension to the brain from the gut by sympathetic and parasympathetic projections (40). In our experiment, abundant prions were observed in the brainstem of cattle with clinical signs of BSE, which is similar to the amount in their thalamus or midbrain regions. Interestingly, prions in the brainstem of cattle with clinical evidence of BSE seeded the RT-QuIC reactions faster than any other brain region despite the brainstem area having lower EIA OD values (Table 2) in comparison to other brain regions. This suggests that higher concentrations of prions do not necessarily seed the reaction faster. Perhaps prions of the brainstem exist in a preferred conformation for better conversion despite being present in lower concentrations.

snip... 



The 2004 enhanced BSE surveillance program was so flawed, that one of the top TSE prion Scientist for the CDC, Dr. Paul Brown stated ; Brown, who is preparing a scientific paper based on the latest two mad cow cases to estimate the maximum number of infected cows that occurred in the United States, said he has "absolutely no confidence in USDA tests before one year ago" because of the agency's reluctance to retest the Texas cow that initially tested positive.

see ;



CDC - Bovine Spongiform Encephalopathy and Variant Creutzfeldt ... Dr. Paul Brown is Senior Research Scientist in the Laboratory of Central Nervous System ... Address for correspondence: Paul Brown, Building 36, Room 4A-05, ...


PAUL BROWN COMMENT TO ME ON THIS ISSUE

Tuesday, September 12, 2006 11:10 AM

"Actually, Terry, I have been critical of the USDA handling of the mad cow issue for some years, and with Linda Detwiler and others sent lengthy detailed critiques and recommendations to both the USDA and the Canadian Food Agency."

OR, what the Honorable Phyllis Fong of the OIG found ;

Finding 2 Inherent Challenges in Identifying and Testing High-Risk Cattle Still Remain


IT is of my opinion, that the OIE and the USDA et al, are the soul reason, and responsible parties, for Transmissible Spongiform Encephalopathy TSE prion diseases, including typical and atypical BSE, typical and atypical Scrapie, and all strains of CWD, and human TSE there from, spreading around the globe. I have lost all confidence of this organization as a regulatory authority on animal disease, and consider it nothing more than a National Trading Brokerage for all strains of animal TSE, just to satisfy there commodity. AS i said before, OIE should hang up there jock strap now, since it appears they will buckle every time a country makes some political hay about trade protocol, commodities and futures. IF they are not going to be science based, they should do everyone a favor and dissolve there organization. JUST because of low documented human body count with nvCJD and the long incubation periods, the lack of sound science being replaced by political and corporate science in relations with the fact that science has now linked some sporadic CJD with atypical BSE and atypical scrapie, and the very real threat of CWD being zoonosis, I believed the O.I.E. has failed terribly and again, I call for this organization to be dissolved... 

Monday, May 05, 2014

Member Country details for listing OIE CWD 2013 against the criteria of Article 1.2.2., the Code Commission recommends consideration for listing



Friday, December 5, 2014

SPECIAL ALERT The OIE recommends strengthening animal disease surveillance worldwide



O.4.3

Spread of BSE prions in cynomolgus monkeys (Macaca fascicularis) after oral transmission

Edgar Holznagel1, Walter Schulz-Schaeffer2, Barbara Yutzy1, Gerhard Hunsmann3, Johannes Loewer1 1Paul-Ehrlich-Institut, Federal Institute for Sera and Vaccines, Germany; 2Department of Neuropathology, Georg-August University, Göttingen, Germany, 3Department of Virology and Immunology, German Primate Centre, Göttingen, Germany

Background: BSE-infected cynomolgus monkeys represent a relevant animal model to study the pathogenesis of variant Creutzfeldt-Jacob disease (vCJD).

Objectives: To study the spread of BSE prions during the asymptomatic phase of infection in a simian animal model.

Methods: Orally BSE-dosed macaques (n=10) were sacrificed at defined time points during the incubation period and 7 orally BSE-dosed macaques were sacrificed after the onset of clinical signs. Neuronal and non-neuronal tissues were tested for the presence of proteinase-K-resistant prion protein (PrPres) by western immunoblot and by paraffin-embedded tissue (PET) blot technique.

Results: In clinically diseased macaques (5 years p.i. + 6 mo.), PrPres deposits were widely spread in neuronal tissues (including the peripheral sympathetic and parasympathetic nervous system) and in lymphoid tissues including tonsils. In asymptomatic disease carriers, PrPres deposits could be detected in intestinal lymph nodes as early as 1 year p.i., but CNS tissues were negative until 3 – 4 years p.i. Lumbal/sacral segments of the spinal cord and medulla oblongata were PrPres positive as early as 4.1 years p.i., whereas sympathetic trunk and all thoracic/cervical segments of the spinal cord were still negative for PrPres. However, tonsil samples were negative in all asymptomatic cases.

Discussion: There is evidence for an early spread of BSE to the CNS via autonomic fibres of the splanchnic and vagus nerves indicating that trans-synaptical spread may be a time-limiting factor for neuroinvasion. Tonsils were predominantly negative during the main part of the incubation period indicating that epidemiological vCJD screening results based on the detection of PrPres in tonsil biopsies may mostly tend to underestimate the prevalence of vCJD among humans.

P.4.23

Transmission of atypical BSE in humanized mouse models

Liuting Qing1, Wenquan Zou1, Cristina Casalone2, Martin Groschup3, Miroslaw Polak4, Maria Caramelli2, Pierluigi Gambetti1, Juergen Richt5, Qingzhong Kong1 1Case Western Reserve University, USA; 2Instituto Zooprofilattico Sperimentale, Italy; 3Friedrich-Loeffler-Institut, Germany; 4National Veterinary Research Institute, Poland; 5Kansas State University (Previously at USDA National Animal Disease Center), USA

Background: Classical BSE is a world-wide prion disease in cattle, and the classical BSE strain (BSE-C) has led to over 200 cases of clinical human infection (variant CJD). Atypical BSE cases have been discovered in three continents since 2004; they include the L-type (also named BASE), the H-type, and the first reported case of naturally occurring BSE with mutated bovine PRNP (termed BSE-M). The public health risks posed by atypical BSE were largely undefined.

Objectives: To investigate these atypical BSE types in terms of their transmissibility and phenotypes in humanized mice. Methods: Transgenic mice expressing human PrP were inoculated with several classical (C-type) and atypical (L-, H-, or Mtype) BSE isolates, and the transmission rate, incubation time, characteristics and distribution of PrPSc, symptoms, and histopathology were or will be examined and compared.

Results: Sixty percent of BASE-inoculated humanized mice became infected with minimal spongiosis and an average incubation time of 20-22 months, whereas only one of the C-type BSE-inoculated mice developed prion disease after more than 2 years. Protease-resistant PrPSc in BASE-infected humanized Tg mouse brains was biochemically different from bovine BASE or sCJD. PrPSc was also detected in the spleen of 22% of BASE-infected humanized mice, but not in those infected with sCJD. Secondary transmission of BASE in the humanized mice led to a small reduction in incubation time. The atypical BSE-H strain is also transmissible with distinct phenotypes in the humanized mice, but no BSE-M transmission has been observed so far.

Discussion: Our results demonstrate that BASE is more virulent than classical BSE, has a lymphotropic phenotype, and displays a modest transmission barrier in our humanized mice.

BSE-H is also transmissible in our humanized Tg mice.

The possibility of more than two atypical BSE strains will be discussed.

Supported by NINDS NS052319, NIA AG14359, and NIH AI 77774.


P03.137

Transmission of BSE to Cynomolgus Macaque, a Non-human Primate; Development of Clinical Symptoms and Tissue Distribution of PrPSC

Yamakawa, Y1; Ono, F2; Tase, N3; Terao, K3; Tannno, J3; Wada, N4; Tobiume, M5; Sato, Y5; Okemoto-Nakamura, Y1; Hagiwara, K1; Sata, T5 1National Institure of Infectious diseases, Cell biology and Biochemistry, Japan; 2Corporation for Production and Research Laboratory Primates., Japan; 3National Institure of Biomedical Innovation, Tsukuba Primate Reserch Center, Japan; 4Yamauchi Univ., Veterinary Medicine, Japan; 5National Institure of Infectious diseases, Pathology, Japan

Two of three cynomolgus monkeys developed abnormal neuronal behavioral signs at 30-(#7) and 28-(#10) months after intracerebral inoculation of 200ul of 10% brain homogenates of BSE affected cattle (BSE/JP6). Around 30 months post inoculation (mpi), they developed sporadic anorexia and hyperekplexia with squeal against environmental stimulations such as light and sound. Tremor, myoclonic jerk and paralysis became conspicuous during 32 to 33-mpi, and symptoms become worsened according to the disease progression. Finally, one monkey (#7) fell into total paralysis at 36-mpi. This monkey was sacrificed at 10 days after intensive veterinary care including infusion and per oral supply of liquid food. The other monkey (#10) had to grasp the cage bars to keep an upright posture caused by the sever ataxia. This monkey was sacrificed at 35-mpi. EEG of both monkeys showed diffuse slowing. PSD characteristic for sporadic CJD was not observed in both monkeys. The result of forearm movement test showed the hypofunction that was observed at onset of clinical symptoms. Their cognitive function determined by finger maze test was maintained at the early stage of sideration. However, it was rapidly impaired followed by the disease progression. Their autopsied tissues were immunochemically investigated for the tissue distribution of PrPSc. Severe spongiform change in the brain together with heavy accumulation of PrPSc having the type 2B/4 glycoform profile confirmed successful transmission of BSE to Cynomolgus macaques. Granular and linear deposition of PrPSC was detected by IHC in the CNS of both monkeys. At cerebral cortex, PrPSC was prominently accumulated in the large plaques. Sparse accumulation of PrPSc was detected in several peripheral nerves of #7 but not in #10 monkey, upon the WB analysis. Neither #7 nor #10 monkey accumulated detectable amounts of PrPSc in their lymphatic organs such as tonsil, spleen, adrenal grands and thymus although PrPSc was barely detected in the submandibular lymph node of #7 monkey. Such confined tissue distribution of PrPSc after intracerebral infection with BSE agent is not compatible to that reported on the Cynomolgus macaques infected with BSE by oral or intra-venous (intra-peritoneal) routs, in which PrPSc was accumulated at not only CNS but also widely distributed lymphatic tissues.

P04.27

Experimental BSE Infection of Non-human Primates: Efficacy of the Oral Route

Holznagel, E1; Yutzy, B1; Deslys, J-P2; Lasmézas, C2; Pocchiari, M3; Ingrosso, L3; Bierke, P4; Schulz-Schaeffer, W5; Motzkus, D6; Hunsmann, G6; Löwer, J1 1Paul-Ehrlich-Institut, Germany; 2Commissariat à l´Energie Atomique, France; 3Instituto Superiore di Sanità, Italy; 4Swedish Institute for Infectious Disease control, Sweden; 5Georg August University, Germany; 6German Primate Center, Germany

Background: In 2001, a study was initiated in primates to assess the risk for humans to contract BSE through contaminated food. For this purpose, BSE brain was titrated in cynomolgus monkeys.

Aims: The primary objective is the determination of the minimal infectious dose (MID50) for oral exposure to BSE in a simian model, and, by in doing this, to assess the risk for humans. Secondly, we aimed at examining the course of the disease to identify possible biomarkers.

Methods: Groups with six monkeys each were orally dosed with lowering amounts of BSE brain: 16g, 5g, 0.5g, 0.05g, and 0.005g. In a second titration study, animals were intracerebrally (i.c.) dosed (50, 5, 0.5, 0.05, and 0.005 mg).

Results: In an ongoing study, a considerable number of high-dosed macaques already developed simian vCJD upon oral or intracerebral exposure or are at the onset of the clinical phase. However, there are differences in the clinical course between orally and intracerebrally infected animals that may influence the detection of biomarkers.

Conclusions: Simian vCJD can be easily triggered in cynomolgus monkeys on the oral route using less than 5 g BSE brain homogenate. The difference in the incubation period between 5 g oral and 5 mg i.c. is only 1 year (5 years versus 4 years). However, there are rapid progressors among orally dosed monkeys that develop simian vCJD as fast as intracerebrally inoculated animals.

The work referenced was performed in partial fulfilment of the study “BSE in primates“ supported by the EU (QLK1-2002-01096).http://www.neuroprion.org/resources/pdf_docs/conferences/prion2007/abstract_book.pdf

Simian vCJD can be easily triggered in cynomolgus monkeys on the oral route using less than 5 g BSE brain homogenate.


WE know now, and we knew decades ago, that 5.5 grams of suspect feed in TEXAS was enough to kill 100 cows.

look at the table and you'll see that as little as 1 mg (or 0.001 gm) caused 7% (1 of 14) of the cows to come down with BSE;

Risk of oral infection with bovine spongiform encephalopathy agent in primates

Corinne Ida Lasmézas, Emmanuel Comoy, Stephen Hawkins, Christian Herzog, Franck Mouthon, Timm Konold, Frédéric Auvré, Evelyne Correia, Nathalie Lescoutra-Etchegaray, Nicole Salès, Gerald Wells, Paul Brown, Jean-Philippe Deslys Summary The uncertain extent of human exposure to bovine spongiform encephalopathy (BSE)--which can lead to variant Creutzfeldt-Jakob disease (vCJD)--is compounded by incomplete knowledge about the efficiency of oral infection and the magnitude of any bovine-to-human biological barrier to transmission. We therefore investigated oral transmission of BSE to non-human primates. We gave two macaques a 5 g oral dose of brain homogenate from a BSE-infected cow. One macaque developed vCJD-like neurological disease 60 months after exposure, whereas the other remained free of disease at 76 months. On the basis of these findings and data from other studies, we made a preliminary estimate of the food exposure risk for man, which provides additional assurance that existing public health measures can prevent transmission of BSE to man.

snip...

BSE bovine brain inoculum

100 g 10 g 5 g 1 g 100 mg 10 mg 1 mg 0·1 mg 0·01 mg

Primate (oral route)* 1/2 (50%)

Cattle (oral route)* 10/10 (100%) 7/9 (78%) 7/10 (70%) 3/15 (20%) 1/15 (7%) 1/15 (7%)

RIII mice (ic ip route)* 17/18 (94%) 15/17 (88%) 1/14 (7%)

PrPres biochemical detection

The comparison is made on the basis of calibration of the bovine inoculum used in our study with primates against a bovine brain inoculum with a similar PrPres concentration that was inoculated into mice and cattle.8 *Data are number of animals positive/number of animals surviving at the time of clinical onset of disease in the first positive animal (%). The accuracy of bioassays is generally judged to be about plus or minus 1 log. ic ip=intracerebral and intraperitoneal.

Table 1: Comparison of transmission rates in primates and cattle infected orally with similar BSE brain inocula

Published online January 27, 2005


It is clear that the designing scientists must also have shared Mr Bradley’s surprise at the results because all the dose levels right down to 1 gram triggered infection.



it is clear that the designing scientists must have also shared Mr Bradleyâs surprise at the results because all the dose levels right down to 1 gram triggered infection.


 


I ask Professor Kong ;

Thursday, December 04, 2008 3:37 PM

Subject: RE: re--Chronic Wating Disease (CWD) and Bovine Spongiform Encephalopathies (BSE): Public Health Risk Assessment

IS the h-BSE more virulent than typical BSE as well, or the same as cBSE, or less virulent than cBSE? just curious.....

Professor Kong reply ;

.....snip

As to the H-BSE, we do not have sufficient data to say one way or another, but we have found that H-BSE can infect humans. I hope we could publish these data once the study is complete. Thanks for your interest.

Best regards, Qingzhong Kong, PhD Associate Professor Department of Pathology Case Western Reserve University Cleveland, OH 44106 USA 

P.4.23 Transmission of atypical BSE in humanized mouse models 

Liuting Qing1, Wenquan Zou1, Cristina Casalone2, Martin Groschup3, Miroslaw Polak4, Maria Caramelli2, Pierluigi Gambetti1, Juergen Richt5, Qingzhong Kong1 1Case Western Reserve University, USA; 2Instituto Zooprofilattico Sperimentale, Italy; 3Friedrich-Loeffler-Institut, Germany; 4National Veterinary Research Institute, Poland; 5Kansas State University (Previously at USDA National Animal Disease Center), USA

Background: Classical BSE is a world-wide prion disease in cattle, and the classical BSE strain (BSE-C) has led to over 200 cases of clinical human infection (variant CJD). Atypical BSE cases have been discovered in three continents since 2004; they include the L-type (also named BASE), the H-type, and the first reported case of naturally occurring BSE with mutated bovine PRNP (termed BSE-M). The public health risks posed by atypical BSE were argely undefined.

Objectives: To investigate these atypical BSE types in terms of their transmissibility and phenotypes in humanized mice.

Methods: Transgenic mice expressing human PrP were inoculated with several classical (C-type) and atypical (L-, H-, or Mtype) BSE isolates, and the transmission rate, incubation time, characteristics and distribution of PrPSc, symptoms, and histopathology were or will be examined and compared.

Results: Sixty percent of BASE-inoculated humanized mice became infected with minimal spongiosis and an average incubation time of 20-22 months, whereas only one of the C-type BSE-inoculated mice developed prion disease after more than 2 years. Protease-resistant PrPSc in BASE-infected humanized Tg mouse brains was biochemically different from bovine BASE or sCJD. PrPSc was also detected in the spleen of 22% of BASE-infected humanized mice, but not in those infected with sCJD. Secondary transmission of BASE in the humanized mice led to a small reduction in incubation time. The atypical BSE-H strain is also transmissible with distinct phenotypes in the humanized mice, but no BSE-M transmission has been observed so far.

Discussion: Our results demonstrate that BASE is more virulent than classical BSE, has a lymphotropic phenotype, and displays a modest transmission barrier in our humanized mice. BSE-H is also transmissible in our humanized Tg mice. The possibility of more than two atypical BSE strains will be discussed.

Supported by NINDS NS052319, NIA AG14359, and NIH AI 77774.


see full text ;


>>> It is distinct from atypical BSE, which may develop spontaneously, according to information from the U.S. Centers for Disease Control and Prevention.

THIS IS A MYTH $$$

***atypical spontaneous BSE in France LOL***

FRANCE STOPS TESTING FOR MAD COW DISEASE BSE, and here’s why, to many spontaneous events of mad cow disease $$$

***so 20 cases of atypical BSE in France, compared to the remaining 40 cases in the remaining 12 Countries, divided by the remaining 12 Countries, about 3+ cases per country, besides Frances 20 cases. you cannot explain this away with any spontaneous BSe. ...TSS

Sunday, October 5, 2014

France stops BSE testing for Mad Cow Disease


Thursday, March 24, 2016

FRANCE CONFIRMS BOVINE SPONGIFORM ENCEPHALOPATHY BSE MAD COW (ESB) chez une vache dans les Ardennes


***atypical spontaneous BSE in France LOL***

FRANCE STOPS TESTING FOR MAD COW DISEASE BSE, and here’s why, to many spontaneous events of mad cow disease $$$


we have seen the spontaneous BSE epidemic in France, what about the other HIGH INCIDENCE ATYPICAL BSE COUNTRY OF POLAND, another atypical spontaneous event of high incidence. how can this be blamed on a happenstance of nothing, i.e. old age? goes against all junk science to date on the spontaneous atypical BSE i.e.

> In 2015, the OIE determined that atypical BSE occurred spontaneously at a low rate in all cattle populations and would be excluded for BSE risk. ...

>Atypical BSE occurs in older cattle, usually 8 years of age or greater, and does not appear to be associated with contaminated feed. Like classic or sporadic CJD in humans, it seems to arise rarely and spontaneously. 

 POLAND ATYPICAL BSE AND SPORADIC CJD


we have seen the spontaneous BSE epidemic in France, what about the other HIGH INCIDENCE ATYPICAL BSE COUNTRY OF POLAND, another atypical spontaneous event of high incidence. how can this be blamed on a happenstance of nothing, i.e. old age? goes against all junk science to date on the spontaneous atypical BSE i.e.

> In 2015, the OIE determined that atypical BSE occurred spontaneously at a low rate in all cattle populations and would be excluded for BSE risk. ...

>Atypical BSE occurs in older cattle, usually 8 years of age or greater, and does not appear to be associated with contaminated feed. Like classic or sporadic CJD in humans, it seems to arise rarely and spontaneously. 

 POLAND ATYPICAL BSE AND SPORADIC CJD


Atypical status of bovine spongiform encephalopathy in Poland: a molecular typing study

Summary

The aim of this study was to analyze molecular features of protease-resistant prion protein (PrPres) in Western blots of BSE cases diagnosed in Poland with respect to a possible atypical status. Confirmed cases were analyzed by Western blotting with several monoclonal antibodies directed at N-terminal and core epitopes of prion protein (PrP). Most cases showed the classical glycoprofile characterized by the dominance of the di- over the monoglycosylated PrPres band, yielding di-/mono- ratios well above 2 and by reactivity with antibodies having their epitopes in bovine PrP region 110–242 (C-type cases). Surprisingly, seven cases of BSE were atypical. Six were classified as L-type based on a slightly lower molecular mass (Mr) of the non- glycosylated band with respect to C-types and a conspicuously low di-/mono- ratio of glycosylated PrPres bands approaching unity. One case was classified as H-type because of a higher Mr of PrPres bands on the blot when compared with C-type cases. A characteristic epitope of H-type PrPres occurred in the 101–110 region of PrP for which only antibody 12B2 had a sufficient affinity. The occurrence of atypical cases only in animals 9 years of age and older raises questions about the mechanisms of prion diseases and the origin of BSE.


Atypical status of bovine spongiform encephalopathy in Poland: a molecular typing study

M. P. Polak1, J. F. Zmudzinski1, J. G. Jacobs2, J. P. M. Langeveld2

1 National Veterinary Research Institute, Pulawy, Poland

2 Central Institute for Animal Disease Control (CIDC-Lelystad), Lelystad, The Netherlands Received 24 April 2007; Accepted 27 August 2007; Published online 26 September 2007 # Springer-Verlag 2007 

snip...

Clarification of whether these atypical cases represent genuine strains of BSE would be accomplished by transmission studies in mice. Such studies have already been performed in France, Germany and Italy [3, 5, 14, 15]. For H-type cases in France, successful transmission was achieved in both wild-type, and transgenic mice expressing bovine and ovine PrPC. In Germany, successful transmission of both an L-type and an H-type case to transgenic mice overexpressing bovine PrPC has been described. PrPres from those mice was identical to the inoculum used in the study, proving the existence of distinct strains of BSE. All atypical features of those isolates were maintained in the inoculated mice, indicating the existence of several prion strains in cattle, or alternatively a possible evolution to a single BSE strain, as suggested from data obtained by Capobianco et al. with wild-type inbred mice [15]. This second hypothesis could fit with data from the United Kingdom, where over 180,000 cases of BSE were diagnosed by passive surveillance. British and European experience based on tissue analysis from clinically affected animals showed consistent characteristics of BSE agent not only on histological sections from cattle brains but also when inoculating mice, pointing to the existence of one uniform strain of BSE. Therefore, it is possible that a sporadic form of BSE present in the cattle population at a very low rate in the past could have spread to naive animals via contaminated meatand-bone meals. Spontaneous BSE, if it occurs, must be a very rare phenomenon. However, data for Poland, where 14% of all cases comprised an atypical form of BSE, seems to be in contradiction to this hypothesis. But when the average age of all positive cases in Poland is taken into account, BSE is generally found in older animals (mean age of 7.7). Analysis of the age structure of cattle in Poland in the period of 2002–2006 shows that 56–60% of all animals were 7 years old and above. A much larger number of cattle should be tested to get better insight into the real prevalence of atypical BSE. However, current tendencies based on economic analysis point to a decrease in the number of tests performed rather than expanding this scheme any further. It would be sensible to maintain a certain level of testing focused on the older age group to distinguish between a stable, thus sporadic-based, situation of BSE, or alternatively a fade-out, thus epidemic-based, situation. Exploring the subject of spontaneous BSE in the cattle population may be ceased for economic reasons, and it may never be known while this answer is in our reach thanks to great financial efforts in recent years. 


Poland is Proof atypical BSE is NOT an old cow spontaneous disease...tss

Number of reported cases of bovine spongiform encephalopathy (BSE) in farmed cattle worldwide* (excluding the United Kingdom) Country/Year 

Poland 

89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16

0 0 0 0 0 0 0 0 0 0 0 0 0 4f 5 11 19 10 9 5 4 2 1m 3 1 0 0 0


Source: USDA, APHIS, VS 

What is the level of passenger traffic arriving in the United States from Poland? 

A total of 188,946 passengers arrived at US airports on direct flights from Poland in fiscal year 2000. 

An undetermined number of passengers arrived in the US from Poland via indirect flights. 

Under APHIS-PPQ’s agricultural quarantine inspection monitoring, 451 air passengers from Poland were sampled for items of agricultural interest in fiscal year 2000. 

Thirteen (13) of these passengers, or 2.9 percent, carried a total of 26.2 kg of meat items that could potentially harbor the pathogen(s) that cause BSE. 

None of these passengers from whom meat items were confiscated reported plans to visit or work on a ranch or farm during their visit to the US. 

Source: US Department of Transportation, and APHIS-PPQ Agricultural Quarantine Inspection data base CEI’s plans for follow up: CEI has no plans to provide additional information on this situation. If you need more information or wish to comment, you may contact Judy Akkina at (970) 490-7852 or Carol Tuszynski at (970) 490-7893. 


What measures has USDA-APHIS taken to prevent the introduction of BSE? To prevent BSE from entering the United States, APHIS has restricted the importation of live ruminants and certain ruminant products from countries where BSE is known to exist.

Greetings FDA and public, 

if you go to the below site, and search all BSE known countries and check out their air traffic illegal meat they have confiscated, and check out the low number checked, compared to actual passenger traffic, would not take too much for some nut to bring in FMD/TSEs into the USA as a 'suitcase bomb'. 

[[Under APHIS-PPQ's agricultural quarantine inspection monitoring, 284 air passengers from Israel were sampled for items of agricultural interest in fiscal year 2001. Seven of these passengers, or 2 percent, carried a total of 11 kg of meat items that could potentially harbor the pathogen that causes BSE. None of these passengers from whom meat items were confiscated reported plans to visit or work on a ranch or farm during their visit to the U.S.]] 

if they were to have questioned the terrorist that bombed the Twin Towers with jets, if they were to have questioned them at flight school in the USA, i am sure that they would have said they did not intend to visit the Twin Towers as a flying bomb either. what am i thinking, they probably did ask this? stupid me. 

[[In 1999 a small amount of non-species specific meat and offal was imported and a small amount of fetal bovine serum (FBS) was also imported. FBS is considered to have a relatively low risk of transmitting BSE.]] more of the USA infamous 'non-species coding system', wonder how many of these species are capable of carrying a TSE? 

snip... 

A total of 524,401 passengers arrived on direct flights to the U.S. from Israel in fiscal year 2000. This number does not include passengers who arrived in the U.S. from Israel via indirect flights. Under APHIS-PPQ's agricultural quarantine inspection monitoring, 284 air passengers from Israel were sampled for items of agricultural interest in fiscal year 2001. Seven of these passengers, or 2 percent, carried a total of 11 kg of meat items that could potentially harbor the pathogen that causes BSE. None of these passengers from whom meat items were confiscated reported plans to visit or work on a ranch or farm during their visit to the U.S. 



PRION 2018 CONFERENCE

P98 The agent of H-type bovine spongiform encephalopathy associated with E211K prion protein polymorphism transmits after oronasal challenge 

Greenlee JJ (1), Moore SJ (1), and West Greenlee MH (2) (1) United States Department of Agriculture, Agricultural Research Service, National Animal Disease Center, Virus and Prion Research Unit, Ames, IA, United States (2) Department of Biomedical Sciences, Iowa State University College of Veterinary Medicine, Ames, IA, United States. 

reading up on this study from Prion 2018 Conference, very important findings ;

***> This study demonstrates that the H-type BSE agent is transmissible by the oronasal route. 

***> These results reinforce the need for ongoing surveillance for classical and atypical BSE to minimize the risk of potentially infectious tissues entering the animal or human food chains.

PRION 2018 CONFERENCE ABSTRACT


WEDNESDAY, OCTOBER 24, 2018 

Experimental Infection of Cattle With a Novel Prion Derived From Atypical H-Type Bovine Spongiform Encephalopathy



MONDAY, JANUARY 09, 2017 

Oral Transmission of L-Type Bovine Spongiform Encephalopathy Agent among Cattle 

CDC Volume 23, Number 2—February 2017 

*** Consumption of L-BSE–contaminated feed may pose a risk for oral transmission of the disease agent to cattle.

*** Consumption of L-BSE–contaminated feed may pose a risk for oral transmission of the disease agent to cattle.


TUESDAY, AUGUST 28, 2018 

USDA finds BSE infection in Florida cow 08/28/18 6:43 PM


WEDNESDAY, AUGUST 29, 2018 

USDA Announces Atypical Bovine Spongiform Encephalopathy Detection USDA 08/29/2018 10:00 AM EDT


WEDNESDAY, AUGUST 29, 2018 

Transmissible Spongiform Encephalopathy TSE Prion Atypical BSE Confirmed Florida Update USA August 28, 2018



 MONDAY, FEBRUARY 04, 2019 

POLAND DETECTS BOVINE SPONGIFORM ENCEPHALOPATHY BSE TSE PRION 

Poland is Proof atypical BSE is NOT an old cow spontaneous disease...tss 


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.....



TUESDAY, APRIL 18, 2017 

*** EXTREME USA FDA PART 589 TSE PRION FEED LOOP HOLE STILL EXIST, AND PRICE OF POKER GOES UP ***



***> Wednesday, January 23, 2019 

***> CFIA SFCR Guidance on Specified risk material (SRM) came into force on January 15, 2019 <***



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.


***> IMPORTS AND EXPORTS <***

***SEE MASSIVE AMOUNTS OF BANNED ANIMAL PROTEIN AKA MAD COW FEED IN COMMERCE USA DECADES AFTER POST BAN ***



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.



Chronic Wasting Disease CWD TSE Prion

Cervid to human prion transmission 

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

We hypothesize that: 

(1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues; 

(2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence; 

(3) Reliable essays can be established to detect CWD infection in humans; and 

(4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches. 


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. 

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. <*** 

https://prion2018.org/

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. 

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 

https://prion2018.org/wp-content/uploads/2018/05/program.pdf 

https://prion2018.org/

THURSDAY, OCTOBER 04, 2018 

Cervid to human prion transmission 5R01NS088604-04 Update 

http://grantome.com/grant/NIH/R01-NS088604-04 

http://chronic-wasting-disease.blogspot.com/2018/10/cervid-to-human-prion-transmission.html

snip...full text;

SATURDAY, FEBRUARY 09, 2019 

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


***> USDA APHIS FDA CWD BSE SCRAPIE CJD UPDATE MARCH 2019 The Full Monty


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


THURSDAY, MARCH 14, 2019 

USDA APHIS CDC FDA BSE TSE PRION UPDATE 2019


FRIDAY, MARCH 15, 2019 

USDA APHIS SCRAPIE TSE PRION Sheep and Goat Health Update 2019



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


Rapid recontamination of a farm building occurs after attempted prion removal


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

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 



MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019

MONDAY, FEBRUARY 25, 2019 

MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019


SATURDAY, MARCH 16, 2019 

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



TUESDAY, MARCH 26, 2019 

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



Terry S. Singeltary Sr.


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