Ireland OIE Atypical BSE H-type
Ireland OIE Atypical BSE H-type
OIE Bovine spongiform encephalopathy, Ireland
Information received on 22/05/2020 from Dr Martin Blake, Chief Veterinary Officer, Department of Agriculture, Food and the Marine, Agriculture House, Dublin, Ireland
Summary
Report type Immediate notification (Final report)
Date of start of the event 12/05/2020
Date of confirmation of the event 13/05/2020
Report date 22/05/2020
Date submitted to OIE 22/05/2020
Date event resolved 22/05/2020
Reason for notification Recurrence of a listed disease
Date of previous occurrence 18/01/2017
Manifestation of disease Clinical disease Causal agent BSE prion
Nature of diagnosis Laboratory (advanced)
This event pertains to the whole country
New outbreaks (1)
Outbreak 1 Fethard, Tipperary
Date of start of the outbreak 12/05/2020
Outbreak status Resolved (22/05/2020)
Epidemiological unit Farm
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Cattle 9 1 1 8 0
Affected population One case animal. There are 8 susceptible animals: 6 cohorts and 2 progeny. All susceptible animals were culled and tested negative for BSE.
Summary of outbreaks Total outbreaks: 1
Total animals affected
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Cattle 9 1 1 8 0
Outbreak statistics
Species Apparent morbidity rate Apparent mortality rate Apparent case fatality rate Proportion susceptible animals lost*
Cattle 11.11% 11.11% 100.00% 100.00%
*Removed from the susceptible population through death, destruction and/or slaughter
Epidemiology
Source of the outbreak(s) or origin of infection
Unknown or inconclusive
Epidemiological comments
On the 13/05/2020, the Department of Agriculture, Food and the Marine (DAFM) was advised of a positive result to a rapid screening test carried out by an accredited private laboratory approved by the competent authority. The suspect animal was sampled by DAFM staff as part of the ongoing official sampling of all fallen animals of 48 months and older. The sample material and brain were subsequently forwarded to the National Reference Laboratory (NRL) where samples from different brain areas were subject to confirmatory testing using an OIE approved confirmatory western blot method, a two-blot protocol for the classification of BSE isolates. All the samples had an identical molecular pattern indicating atypical H type BSE. In accordance with NRL protocols, samples from the animal were then sent for histopathology and immunohistochemistry on the medulla of the brain. Final confirmatory test results were received from the NRL on 22nd of May 2020 confirming the case to be atypical H type BSE. The cow involved in this case was a 14-year-old Limousin cow born on the 8th of March 2006. There are 73 cattle on the animal identification and movement register for the herd. The herd is a suckler herd. The cow remained in that herd until her death on Saturday May 9th. The cow had had a history of neurological signs which were first noted at the end of March 2020, where the cow became ataxic and recumbent, but got back on her feet with some assistance. A further such episode occurred in April 2020, and again on Saturday May 9th. The farmer intended to call his private veterinary surgeon (PVP) to look at the animal at that time, but she had died before he had the opportunity to call his PVP. The cow was well conditioned, up to her death.
Control measures
Measures applied
Movement control inside the country
Official disposal of carcasses, by-products and waste
Stamping out
Vaccination permitted (if a vaccine exists)
No treatment of affected animals
Measures to be applied
No other measures
Diagnostic test results
Laboratory name and type Species Test Test date Result
Central Veterinary Research Laboratory (National laboratory) Cattle histopathological examination 19/05/2020 Positive
Central Veterinary Research Laboratory (National laboratory) Cattle immunohistochemical test 18/05/2020 Positive
Central Veterinary Research Laboratory (National laboratory) Cattle western blot 19/05/2020 Positive
Enfer (Private Laboratory) Cattle rapid tests 13/05/2020 Positive
Future Reporting
The event is resolved. No more reports will be submitted.
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TUESDAY, JANUARY 24, 2017
IRL 24-01-17 OIE Alert - Alerta - Alerte - Bovine spongiform encephalopathy - Encéphalopathie spongiforme bovine - Encefalopatía espongiforme bovina
Docket No. APHIS-2014-0107 Bovine Spongiform Encephalopathy; Importation of Animals and Animal Products Singeltary Submission Terry S. Singeltary
Abstract
Comment View document:Docket No. APHIS-2014-0107 Bovine Spongiform Encephalopathy; Importation of Animals and Animal Products Singeltary Submission ;
I believe that there is more risk to the world from Transmissible Spongiform Encephalopathy TSE prion aka mad cow type disease now, coming from the United States and all of North America, than there is risk coming to the USA and North America, from other Countries. I am NOT saying I dont think there is any risk for the BSE type TSE prion coming from other Countries, I am just saying that in 2015, why is the APHIS/USDA/FSIS/FDA still ignoring these present mad cow risk factors in North America like they are not here?
North America has more strains of TSE prion disease, in more species (excluding zoo animals in the early BSE days, and excluding the Feline TSE and or Canine TSE, because they dont look, and yes, there has been documented evidence and scientific studies, and DEFRA Hound study, that shows the canine spongiform encephalopathy is very possible, if it has not already happened, just not documented), then any other Country in the world.
Mink TME, Deer Elk cervid CWD (multiple strains), cBSE cattle, atypical L-type BSE cattle, atypical H-type BSE cattle, atyical HG type BSE cow (the only cow documented in the world to date with this strain), typical sheep goat Scrapie (multiple strains), and the atypical Nor-98 Scrapie, which has been linked to sporadic CJD, Nor-98 atypical Scrapie has spread from coast to coast.
sporadic CJD on the rise, with different strains mounting, victims becoming younger, with the latest nvCJD human mad cow case being documented in Texas again, this case, NOT LINKED TO EUROPEAN TRAVEL CDC.
typical BSE can propagate as nvCJD and or sporadic CJD (Collinge et al), and sporadic CJD has now been linked to atypical BSE, Scrapie and atypical Scrapie, and scientist are very concerned with CWD TSE prion in the Cervid populations.
in my opinion, the BSE MRR policy, which overtook the BSE GBR risk assessments for each country, and then made BSE confirmed countries legal to trade mad cow disease, which was all brought forth AFTER that fateful day December 23, 2003, when the USA lost its gold card i.e. BSE FREE status, thats the day it all started.
once the BSE MRR policy was shoved down every countries throat by USDA inc and the OIE, then the legal trading of Scrapie was validated to be a legal trading commodity, also shoved through by the USDA inc and the OIE, the world then lost 30 years of attempted eradication of the BSE TSE prion disease typical and atypical strains, and the BSE TSE Prion aka mad cow type disease was thus made a legal trading commodity, like it or not. its all about money now folks, trade, to hell with human health with a slow incubating disease, that is 100% fatal once clinical, and forget the fact of exposure, sub-clinical infection, and friendly fire there from i.e. iatrogenic TSE prion disease, the pass it forward mode of the TSE PRION aka mad cow type disease. its all going to be sporadic CJD or sporadic ffi, or sporadic gss, or now the infamous VPSPr. ...problem solved $$$
the USDA/APHIS/FSIS/FDA triple mad cow BSE firewall, well, that was nothing but ink on paper. for this very reason I believe the BSE MRR policy is a total failure, and that this policy should be immediately withdrawn, and set back in place the BSE GBR Risk Assessments, with the BSE GBR risk assessments set up to monitor all TSE PRION disease in all species of animals, and that the BSE GBR risk assessments be made stronger than before.
lets start with the recent notice that beef from Ireland will be coming to America. Ireland confirmed around 1655 cases of mad cow disease. with the highest year confirming about 333 cases in 2002, with numbers of BSE confirmed cases dropping from that point on, to a documentation of 1 confirmed case in 2013, to date. a drastic decrease in the feeding of cows to cows i.e. the ruminant mad cow feed ban, and the enforcement of that ban, has drastically reduced the number of BSE cases in Europe, minus a few BABs or BARBs.
a far cry from the USDA FDA triple BSE firewall, which was nothing more than ink on paper, where in 2007, in one week recall alone, some 10 MILLION POUNDS OF BANNED POTENTIAL MAD COW FEED WENT OUT INTO COMMERCE IN THE USA. this is 10 years post feed ban.
in my honest opinion, due to the blatant cover up of BSE TSE prion aka mad cow disease in the USA, we still have no clue as to the true number of cases of BSE mad cow disease in the USA or North America as a whole. ...just saying.
Number of reported cases of bovine spongiform encephalopathy (BSE) in farmed cattle worldwide* (excluding the United Kingdom) Country/Year
snip...
please see attached pdf file, with references of breaches in the USA triple BSE mad cow firewalls, and recent science on the TSE prion disease. ...TSS
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Sunday, January 11, 2015
Docket No. APHIS-2014-0107 Bovine Spongiform Encephalopathy; Importation of Animals and Animal Products Singeltary Submission
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
http://animalhealthreportpriontse..blogspot.com/2018/08/usda-finds-bse-infection-in-florida-cow.html
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
IN A NUT SHELL ; (Adopted by the International Committee of the OIE on 23 May 2006) 11. Information published by the OIE is derived from appropriate declarations made by the official Veterinary Services of Member Countries. The OIE is not responsible for inaccurate publication of country disease status based on inaccurate information or changes in epidemiological status or other significant events that were not promptly reported to the Central Bureau,
MONDAY, JANUARY 21, 2019
Bovine Spongiform Encephalopathy BSE TSE Prion Surveillance FDA USDA APHIS FSIS UPDATE 2019
USA MAD COW CASE 2018 FLORIDA
WEDNESDAY, SEPTEMBER 26, 2018
JAVMA In Short Update USDA announces detection of atypical BSE
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.
THURSDAY, OCTOBER 04, 2018
Cervid to human prion transmission 5R01NS088604-04 Update
Saturday, December 15, 2018
***> ADRD Summit RFI Singeltary COMMENT SUBMISSION BSE, SCRAPIE, CWD, AND HUMAN TSE PRION DISEASE December 14, 2018
SATURDAY, JANUARY 5, 2019
Low levels of classical BSE infectivity in rendered fat tissue
***> FRIDAY, DECEMBER 14, 2018 MAD COW USA FLASHBACK Texas Style
FRIDAY DECEMBER 14, 2018
THURSDAY, JANUARY 3, 2019
MAD COW USDA DISEASE BSE TSE Prion
THURSDAY, OCTOBER 22, 2015
Former Ag Secretary Ann Veneman talks women in agriculture and we talk mad cow disease USDA and what really happened
HOW TO COVER UP MAD COW DISEASE IN TEXAS
WEDNESDAY, AUGUST 29, 2018
OIE Bovine spongiform encephalopathy, United States of America Information received on 29/08/2018 from Dr John Clifford, Official Delegate, Chief Trade Advisor, APHIS USDA
''The event is resolved. No more reports will be submitted.''
well, so much for those herd mates exposed to this atypical BSE cow, and all those trace in and trace outs.
The OIE, USDA, and the BSE MRR policy is a joke, a sad, very sad joke...
Saturday, July 23, 2016
BOVINE SPONGIFORM ENCEPHALOPATHY BSE TSE PRION SURVEILLANCE, TESTING, AND SRM REMOVAL UNITED STATE OF AMERICA UPDATE JULY 2016
Tuesday, July 26, 2016
Atypical Bovine Spongiform Encephalopathy BSE TSE Prion UPDATE JULY 2016
Monday, June 20, 2016
Specified Risk Materials SRMs BSE TSE Prion Program
Wednesday, January 23, 2019
CFIA SFCR Guidance on Specified risk material (SRM) came into force on January 15, 2019
Saturday, July 23, 2016
BOVINE SPONGIFORM ENCEPHALOPATHY BSE TSE PRION SURVEILLANCE, TESTING, AND SRM REMOVAL UNITED STATE OF AMERICA UPDATE JULY 2016
http://bovineprp.blogspot.com/2016/07/bovine-spongiform-encephalopathy-bse.html
Tuesday, July 26, 2016
Atypical Bovine Spongiform Encephalopathy BSE TSE Prion UPDATE JULY 2016
http://bse-atypical.blogspot.com/2016/07/atypical-bovine-spongiform.html
America BSE 589.2001 FEED REGULATIONS, BSE SURVEILLANCE, BSE TESTING, and CJD TSE Prion
***> cattle, pigs, sheep, cwd, tse, prion, oh my!
***> In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006).
Sheep and cattle may be exposed to CWD via common grazing areas with affected deer but so far, appear to be poorly susceptible to mule deer CWD (Sigurdson, 2008). In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006). It is not known how susceptible humans are to CWD but given that the prion can be present in muscle, it is likely that humans have been exposed to the agent via consumption of venison (Sigurdson, 2008). Initial experimental research suggests that human susceptibility to CWD is low and there may be a robust species barrier for CWD transmission to humans (Sigurdson, 2008), however the risk appetite for a public health threat may still find this level unacceptable.
cwd scrapie pigs oral routes
***> However, at 51 months of incubation or greater, 5 animals were positive by one or more diagnostic methods. Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie. <***
>*** Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health. <***
***> Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 5="" 6="" at="" by="" detected="" eia.="" examined="" group="" in="" intracranial="" least="" lymphoid="" month="" months="" of="" one="" pigs="" positive="" prpsc="" quic="" the="" tissues="" was="">6 months group, 5/6 pigs in the oral <6 4="" and="" group="" months="" oral="">6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%).
***> Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
Friday, December 14, 2012
DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012
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.....
***> READ THIS VERY, VERY, CAREFULLY, AUGUST 1997 MAD COW FEED BAN WAS A SHAM, AS I HAVE STATED SINCE 1997! 3 FAILSAFES THE FDA ET AL PREACHED AS IF IT WERE THE GOSPEL, IN TERMS OF MAD COW BSE DISEASE IN USA, AND WHY IT IS/WAS/NOT A PROBLEM FOR THE USA, and those are;
BSE TESTING (failed terribly and proven to be a sham)
BSE SURVEILLANCE (failed terribly and proven to be a sham)
BSE 589.2001 FEED REGULATIONS (another colossal failure, and proven to be a sham)
these are facts folks. trump et al just admitted it with the feed ban.
see;
FDA Reports on VFD Compliance
John Maday
August 30, 2019 09:46 AM VFD-Form 007 (640x427)
Before and after the current Veterinary Feed Directive rules took full effect in January, 2017, the FDA focused primarily on education and outreach. ( John Maday ) Before and after the current Veterinary Feed Directive (VFD) rules took full effect in January, 2017, the FDA focused primarily on education and outreach to help feed mills, veterinarians and producers understand and comply with the requirements. Since then, FDA has gradually increased the number of VFD inspections and initiated enforcement actions when necessary. On August 29, FDA released its first report on inspection and compliance activities. The report, titled “Summary Assessment of Veterinary Feed Directive Compliance Activities Conducted in Fiscal Years 2016 – 2018,” is available online.
SUNDAY, SEPTEMBER 1, 2019
***> FDA Reports on VFD Compliance
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 <***
Volume 26, Number 6—June 2020
Dispatch
No Adaptation of the Prion Strain in a Heterozygous Case of Variant Creutzfeldt-Jakob Disease
Aileen Boyle, Chris Plinston, Fraser Laing, Graeme Mackenzie, Robert G. Will, Jean C. Manson, and Abigail B.. DiackComments to Author Author affiliations: The Roslin Institute, Easter Bush, Scotland, UK (A. Boyle, C. Plinston, F. Laing, A.B. Diack); Western General Hospital, Edinburgh, Scotland, UK (G. Mackenzie); University of Edinburgh, Edinburgh (R.G. Will, J.C. Manson) Cite This Article
Abstract
We investigated a clinical case of variant Creutzfeldt-Jakob Disease in a person heterozygous for methionine/valine at codon 129 of the prion protein gene and identified the same strain properties in variant Creutzfeldt-Jakob disease in methionine homozygous persons and in bovine spongiform encephalopathy. These results indicate no adaptation of the agent in a different genetic background.
In 2016, a definite case of clinical variant Creutzfeldt-Jakob disease (vCJD) in a person heterozygous for methionine/valine (MV) at codon 129 of the prion protein gene (PRNP 129MV) was reported in the United Kingdom (1). Given the relatively atypical clinical features in this case, we considered it important to ascertain the strain of prion agent to determine whether there had been strain adaption or whether the patient’s genetic background may have influenced the disease phenotype. We conducted a study to determine whether we could isolate the same prion strain from this case of vCJD in a 129MV individual as was identified in previous 129 methionine homozygous (129MM) genotype vCJD cases, consistent with the hypothesis of a causal link to bovine spongiform encephalopathy (BSE).
The clinical features for this patient were consistent with a diagnosis of either vCJD or sporadic Creutzfeldt-Jakob disease (sCJD). Results from magnetic resonance imaging (MRI) of the patient’s brain were suggestive of sCJD on diffusion-weighted imaging (DWI) sequences, although the single coronal fluid-attenuated inversion recovery (FLAIR) sequence in this case was not diagnostic because of movement artifact. Results of cerebrospinal fluid (CSF) real-time quaking-induced conversion assay analysis and the direct detection assay for vCJD infection in the blood were negative. However, at autopsy, neuropathological examination revealed florid plaques, and biochemical analysis of prion protein (PrP) from the brain confirmed a type 2B profile, both characteristic of vCJD (1). Abnormal PrP was also detected in peripheral tissues. Recent studies in which researchers used protein misfolding cyclic amplification in CSF were positive in this case of vCJD, but not in sCJD cases, including those with a heterozygous genotype (2).
The Study We injected 18 RIII mice with 10% wt/vol frozen central nervous system tissue, 0.02 mL intracerebrally and 0.1 mL intraperitoneally, from a 129MV patient with a clinical case of vCJD (1). The vCJD tissue samples were provided by the NHS National Prion Clinic, University College London (UCL) Hospitals (London, UK), and MRC Prion Unit at UCL and sourced through the MRC Edinburgh Brain Bank (Edinburgh, Scotland, UK). The Brain Bank has full ethics approval and consent for the use of tissue in research (East of Scotland Research Ethics Service, Ref 16/ES/0084) and works within the framework of the Human Tissue (Scotland) Act 2006. We conducted inoculation, clinical scoring, and neuropathological and biochemical analysis of the mice as previously described (3–5). Animal studies were conducted according to the regulations of the UK Home Office Animals (Scientific Procedures) Act 1986.
The isolate from the brain of the 129MV patient transmitted successfully; clinical and neuropathological signs associated with prion disease appeared in the mice. We compared the mean incubation period, neuropathological signs, and biochemical analysis with archived records of UK 129MM vCJD central nervous system transmissions and UK BSE transmissions. Methods used for inoculation, clinical scoring, and neuropathological and biochemical analysis of the mice were described in previous publications (3–5).
Clinical signs with individual incubation periods ranging from 300 to 392 days postinfection (dpi) were apparent in the mice. The major clinical signs were a loss of body weight and body condition with eye winking and gait abnormalities. Toward the end of the clinical phase, a wet genital area could also be observed. Pathologically confirmed disease developed in 14 of 16 mice (mean incubation period + SEM 341 + 6 dpi). This finding is within the range of previous transmission studies for UK vCJD in this mouse line (mean incubation 306–387 dpi) and similar to those for BSE (mean incubation 316–335 dpi).
We also generated a transmissible spongiform encephalopathy (TSE) vacuolation profile from clinically affected RIII mice and compared it with profiles from UK vCJD and BSE transmissions (Figure 1). We observed a mild-to-moderate gray matter vacuolation in the medulla, hypothalamus, and septum and moderate vacuolation in the cochlear nucleus and dorsal raphe (Figure 1; Figure 2, panels A, B).
We conducted an immunohistochemical analysis, which showed abnormal PrP deposition throughout the brain of both a granular and punctate nature (Figure 2, panels C–K). There was heavy staining in the brainstem, particularly the superior vestibular and cochlear nuclei, and lower midbrain, where the substantia nigra was often targeted. Most of the thalamic nuclei exhibited staining, but staining was more intense in the habenular, hypothalamus, and the CA2 region of the hippocampus (Figure 2, panels F–K). Punctate staining was also apparent in the mid-layer of the cortex throughout the brain. This pattern of staining was very similar to that observed in a vCJD and BSE transmission in the United Kingdom, with additional observations of granular deposition in the cerebellar cortex and small plaques occurring in the corpus callosum in 2 of the samples.
Biochemical analysis of the MV isolate confirmed the presence of protease-resistant PrP (PrPres). We identified a similar type 2B–like pattern and glycosylation profile in the RIII mice. This profile is characterized by a predominance of the diglycosylated form of PrPres at ≈30 kDa, a monoglycosylated form at ≈27kDa, and an unglycosylated band at ≈19kDa (Appendix Figure).. The biochemical profile appears identical between the RIII-MV, RIII-MM, and RIII-BSE isolates tested, although the RIII-BSE isolate appeared to have less PrPres.
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Conclusions This transmission study in RIII mice provides evidence that the prion strain isolated from this confirmed case of vCJD in a 129MV person is the same as that identified in typical 129MM vCJD and BSE cases. Further characterization in a range of mouse models is ongoing. However, transmission to RIII mice in previous studies has led to definitive identification of several strains, vCJD and BSE in particular (6,7).
PRNP codon 129 genotype has been shown to be a major factor influencing disease characteristics of Creutzfeldt-Jakob disease (8), but it has not been established if the same is true of vCJD, because previous vCJD infections in 129MV persons exposed to contaminated blood products have been asymptomatic (9,10). Earlier studies using gene-targeted mice inoculated with vCJD predicted that codon 129 genotype would determine disease susceptibility and incubation periods (11), whereas other transgenic mouse studies demonstrated that BSE could transmit with a different phenotype in mice expressing 129MV than that observed in mice expressing 129MM (12).
The clinical diagnosis in the MV case we report was uncertain while the patient was alive, and it was only at autopsy that neuropathology and biochemistry confirmed vCJD. The neurologic features alone cannot be used to discriminate between sCJD and vCJD, and the MRI findings on DWI imaging favored a diagnosis of sCJD. However, the high sensitivity and specificity of MRI for vCJD were determined by analyzing FLAIR images primarily (13) and recent review suggests that DWI imaging may be less specific than FLAIR imaging in vCJD. It is possible that the phenotype of vCJD in this case may have been altered by the heterozygous PRNP background and investigations including CSF protein misfolding cyclic amplification (2), tonsil biopsy, and perhaps FLAIR MRI may contribute to accurate diagnosis of future heterozygous cases.
The identification of vCJD in a 129MV person may indicate the start of a second wave of vCJD in association with the 129MV genotype which is present in around 45% of the UK population (14), although no further cases have been reported since 2016. This case highlights the need to continue surveillance to identify new cases of vCJD and the need for autopsy and strain typing in persons with prion diseases. Changes in clinical disease phenotype could mask the true diagnosis and may be indicative of potential changes in prion disease strains and infectious properties. Strain identification and assessing the infectious properties of prion diseases are essential components in the management of these diseases and have important implications for public health and in determining the prevalence of BSE-related prion disease in humans.
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Ms. Boyle is a research scientist at The Roslin Institute, University of Edinburgh. Her research interests focus on the strain characterization of human and animal prion diseases using in vivo models.
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Acknowledgments We thank the staff of the Biological Research Facility, Roslin Institute, and of Easter Bush Pathology, R(D)SVS, University of Edinburgh, for technical support. We thank David Summers (University of Edinburgh) for input and discussion on MRI imaging of vCJD.
The vCJD tissue samples were acquired through the Edinburgh Brain Bank, which is supported by the Medical Research Council (MR/L016400/1).
This report presents independent research commissioned and funded by the Department of Health and Social Care, Policy Research Programme (Strain typing of vCJD, 007/0195). The views expressed in this publication are those of the author(s) and not necessarily those of the Department of Health and Social Care. The Diack laboratory is also supported by BBSRC Project BBS/E/D/20002173.
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References
Variant Creutzfeldt–Jakob Disease in a Patient with Heterozygosity at PRNP Codon 129
N Engl J Med 2017; 376:292-294January 19, 2017DOI: 10.1056/NEJMc1610003
Share: ArticleMetrics To the Editor:
Prions cause lethal neurodegenerative diseases in mammals and are composed of multichain assemblies of misfolded host-encoded cellular prion protein (PrP). A common polymorphism at codon 129 of the PrP gene (PRNP), where either methionine (M) or valine (V) is encoded, affects the susceptibility to prion disease, as well as the incubation period1 and clinical phenotype of prion disease. Human infection with the epizootic prion disease bovine spongiform encephalopathy resulted in variant Creutzfeldt–Jakob disease, which provoked a public health crisis in the United Kingdom and other regions. All definite cases of variant Creutzfeldt–Jakob disease to date have occurred in patients with the MM genotype at PRNP codon 129.1
A 36-year-old man was referred to the United Kingdom National Prion Clinic in August 2015 with personality change. Over a period of 9 months, he had become uncharacteristically irascible and had progressive episodic memory impairment, gait ataxia, and myoclonus. His score on the Mini–Mental State Examination was 25 (with scores ranging from 0 to 30 and higher scores indicating less impairment); clinical examination revealed extraocular eye-movement abnormalities, pyramidal and cerebellar signs, and multifocal myoclonus. Magnetic resonance imaging of the brain (Figure 1FIGURE 1 MRI of the Brain.) revealed restricted diffusion in the basal ganglia, hypothalami, insular cortexes, and medial thalami but not in the pulvinar nuclei.2 Examination of the cerebrospinal fluid for protein 14-3-3 was negative, as was a real-time quaking-induced conversion assay, although these two tests are known to have low sensitivity for variant Creutzfeldt–Jakob disease.3 His genotype at PRNP codon 129 was MV. During the following 6 months, the patient’s condition declined progressively, and severe dysphagia and agitation occurred shortly before his death in February 2016.
At autopsy, histologic examination of the brain revealed frequent florid and cluster plaques in cerebral and cerebellar cortexes, microvacuolar degeneration in neuropil, and immunostaining for abnormal PrP in a stellate pericellular and perivascular distribution. Minute amounts of protease-resistant PrP (PrPSc) were seen in lymphoid tissue of the spleen. Immunoblotting of brain homogenate revealed type 4 PrPSc (according to the London classification system), which is pathognomonic of variant Creutzfeldt–Jakob disease.4 (For more details, see the Supplementary Appendix, available with the full text of this letter at NEJM.org.)
This patient’s clinical features differed from those of typical variant Creutzfeldt–Jakob disease, and his neuroimaging features suggested a diagnosis of sporadic Creutzfeldt–Jakob disease. He did not meet the epidemiologic diagnostic criteria for probable or possible variant Creutzfeldt–Jakob disease,5 yet the results of the neuropathological examination and molecular strain typing were consistent with variant Creutzfeldt–Jakob disease. It remains uncertain whether this case marks the start of a second wave of variant Creutzfeldt–Jakob disease in persons with the MV genotype at PRNP codon 129 (the most common genotype in the United Kingdom), mirroring the long incubation periods seen in persons with the MV genotype who have other acquired prion diseases, notably kuru.1 This case emphasizes the importance of performing an autopsy and molecular strain typing in cases of prion disease to ascertain the prevalence of human prion disease related to bovine spongiform encephalopathy.
snip...see full text ;
>>> This patient’s clinical features differed from those of typical variant Creutzfeldt–Jakob disease, and his neuroimaging features suggested a diagnosis of sporadic Creutzfeldt–Jakob disease. He did not meet the epidemiologic diagnostic criteria for probable or possible variant Creutzfeldt–Jakob disease,5 yet the results of the neuropathological examination and molecular strain typing were consistent with variant Creutzfeldt–Jakob disease. <<<
Many more people could still die from mad cow disease in the UK
SHORT SHARP SCIENCE
By Debora MacKenzie
18 January 2017
It’s finally happened. Until now, vCJD – the deadly disease caused by infection with BSE, or “mad cow disease” – has struck only people with a certain genetic makeup. Now, for the first time, researchers have confirmed a case in someone with different genes – a finding that could mean we have been misdiagnosing a new wave of cases.
THURSDAY, JANUARY 19, 2017
Variant Creutzfeldt–Jakob Disease in a Patient with Heterozygosity at PRNP Codon 129
Monday, April 20, 2020
PRION2020 POSTPONED TO 2021 – DUE TO CORONAVIRUS (COVID-19)
MONDAY, AUGUST 26, 2019
Creutzfeldt Jakob Disease CJD, TSE, Prion, Surveillance Update August 2019
SUNDAY, MARCH 10, 2019
National Prion Disease Pathology Surveillance Center Cases Examined¹ Updated Feb 1, 2019 Variably protease-sensitive prionopathy VPSPr
***> In conclusion, sensory symptoms and loss of reflexes in Gerstmann-Sträussler-Scheinker syndrome can be explained by neuropathological changes in the spinal cord. We conclude that the sensory symptoms and loss of lower limb reflexes in Gerstmann-Sträussler-Scheinker syndrome is due to pathology in the caudal spinal cord. <***
***> The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.<***
***> 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. <***
***> All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals.<***
***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids.'' Scientific opinion on chronic wasting disease (II) <***
THURSDAY, JANUARY 30, 2020
Docket Number: FDA-2012-D-0307 Recommendations to Reduce the Possible Risk of Transmission of Creutzfeldt-Jakob Disease and Variant Creutzfeldt-Jakob Disease by Blood and Blood Components; Draft Guidance for Industry Draft Guidance for Industry Singeltary Submission
FRIDAY, JANUARY 31, 2020
CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF? Docket Number: FDA-2012-D-0307
Updated April 3, 2020
Year Total Referrals² Prion Disease Sporadic Familial Iatrogenic vCJD
1999 & earlier 381 230 200 27 3 0
2000 145 102 90 12 0 0
2001 209 118 110 8 0 0
2002 241 144 124 18 2 0
2003 259 160 137 21 2 0
2004 316 181 164 16 0 1³
2005 327 178 156 21 1 0
2006 365 179 159 17 1 2⁴
2007 374 210 191 19 0 0
2008 384 221 205 16 0 0
2009 397 231 210 20 1 0
2010 401 246 218 28 0 0
2011 392 238 214 24 0 0
2012 413 244 221 23 0 0
2013 416 258 223 34 1 0
2014 355 208 185 21 1 1⁵
2015 401 263 243 20 0 0
2016 396 277 248 29 0 0
2017 375 266 247 19 0 0
2018 309 223 204 18 1 0
2019 416 270 240 21 0 0
2020 84 56 21 2 0 0
TOTAL 73566 45037 40108 4349 13 4
1Listed based on the year of death or, if not available, on the year of referral;
2Cases with suspected prion disease for which brain tissue was submitted;
3Disease acquired in the United Kingdom;
4Disease acquired in the United Kingdom in one case and in Saudi Arabia in the other;
5Disease possibly acquired in a Middle Eastern or Eastern European country;
6Includes 14 cases in which the diagnosis is pending, and 19 inconclusive cases;
7Includes 42 (9 from 2019, 33 from 2020) cases with type determination pending in which the diagnosis of vCJD has been excluded.
8The sporadic cases include 3906 cases of sporadic Creutzfeldt-Jakob disease (sCJD), 69 cases of Variably Protease-Sensitive Prionopathy (VPSPr) and 35 cases of sporadic Fatal Insomnia (sFI).
9Total does not include 272 Familial cases diagnosed by blood test only.
Monday, February 3, 2020
Informing Patient Contacts About Iatrogenic Creutzfeldt Jakob Disease
Creutzfeldt Jakob Disease CJD
SUNDAY, DECEMBER 29, 2019
Variant CJD 18 years of research and surveillance Variant CJD
18 years of research and surveillance
SATURDAY, JUNE 23, 2018
CDC
***> Diagnosis of Methionine/Valine Variant Creutzfeldt-Jakob Disease by Protein Misfolding Cyclic Amplification
Volume 24, Number 7—July 2018 Dispatch
FRIDAY, MAY 22, 2020
No Adaptation of the Prion Strain in a Heterozygous Case of Variant Creutzfeldt-Jakob Disease Volume 26, Number 6—June 2020
see increase in sporadic cjd cases in Ireland 2017 and 2018...
Sporadic CJD: Definite and probable cases
Country 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Total
Ireland - - - 2 2 6 1 3 5 4 2 7 4 4 3 4 3 5 5 6 4 2 5 4 11 9 101
BSE INQUIRY
Volume 2: Science
4. The link between BSE and vCJD
Summary
4.29 The evidence discussed above that vCJD is caused by BSE seems overwhelming. Uncertainties exist about the cause of CJD in farmers, their wives and in several abattoir workers. It seems that farmers at least might be at higher risk than others in the general population. 1 Increased ascertainment (ie, increased identification of cases as a result of greater awareness of the condition) seems unlikely, as other groups exposed to risk, such as butchers and veterinarians, do not appear to have been affected. The CJD in farmers seems to be similar to other sporadic CJD in age of onset, in respect to glycosylation patterns, and in strain-typing in experimental mice. Some farmers are heterozygous for the methionine/valine variant at codon 129, and their lymphoreticular system (LRS) does not contain the high levels of PrPSc found in vCJD. It remains a remote possibility that when older people contract CJD from BSE the resulting phenotype is like sporadic CJD and is distinct from the vCJD phenotype in younger people...END..TSS
Diagnosis and Reporting of Creutzfeldt-Jakob Disease Singeltary, Sr et al.
JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA
Diagnosis and Reporting of Creutzfeldt-Jakob Disease To the Editor: In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally.
Terry S. Singeltary, Sr Bacliff, Tex 1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Creutzfeldt-Jakob disease in the United States: 1979-1998. JAMA. 2000;284:2322-2323.
Terry S. Singeltary Sr.
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