Saturday, December 3, 2011

Isolation of Prion with BSE Properties from Farmed Goat

Volume 17, Number 12—December 2011

Research

Isolation of Prion with BSE Properties from Farmed Goat

John Spiropoulos , Richard Lockey, Rosemary E. Sallis, Linda A. Terry, Leigh Thorne, Thomas M. Holder, Katy E. Beck, and Marion M. Simmons


Author affiliations: Animal Health and Veterinary Laboratories Agency, Weybridge, Surrey, UK



Abstract

Transmissible spongiform encephalopathies are fatal neurodegenerative diseases that include variant Creutzfeldt-Jakob disease in humans, scrapie in small ruminants, and bovine spongiform encephalopathy (BSE) in cattle. Scrapie is not considered a public health risk, but BSE has been linked to variant Creutzfeldt-Jakob disease. Small ruminants are susceptible to BSE, and in 2005 BSE was identified in a farmed goat in France. We confirm another BSE case in a goat in which scrapie was originally diagnosed and retrospectively identified as suspected BSE. The prion strain in this case was further characterized by mouse bioassay after extraction from formaldehyde-fixed brain tissue embedded in paraffin blocks. Our data show that BSE can infect small ruminants under natural conditions and could be misdiagnosed as scrapie. Surveillance should continue so that another outbreak of this zoonotic transmissible spongiform encephalopathy can be prevented and public health safeguarded.





snip...





Discussion


We confirmed that the agent responsible for TSE in a UK goat, which was initially reported as scrapie in 1990 and subsequently as suspected BSE in 2006 (16), was a BSE agent. This conclusion was based on bioassay of nervous tissue in mice demonstrating similarities of histopathologic lesions, PrPSc mapping in the brain, and WB of PrPSc with those of mice inoculated with BSE from various ovine, caprine, and bovine sources.





From a method perspective, the data suggest that AR, IP, and LP are not optimal bioassay parameters for differentiating TSE sources during first passage because they represent mean values derived from a group of animals that have been inoculated with a specific source. Therefore, a substantial number of animals must die of clinical TSE for these parameters to be meaningful. This finding is a limiting factor in instances in which TSE is diagnosed in only a few animals because of low titer, restricted permissiveness of specific TSE strains in certain laboratory animals, or both. These limitations can be overcome by application of IHC and WB to differentiate BSE from scrapie confidently in individual mice on first passage. Use of IHC has shown that different PrPSc deposits can be identified, and the distribution of each deposit in the brain can be mapped (22,28,32). This approach generates high-resolution data that appear to be specific to individual TSE strains.





The data show that the TSE agents in this study were not altered by the adverse conditions applied to them during histologic procedures. However, titer may decrease, suggesting that the effect of histologic processing is quantitative not qualitative. Therefore, bioassay is a valid approach for identifying BSE in archived histologic material when other techniques are not applicable, as in the current study. Regarding the suitability of different mouse lines for confirming BSE, our data show that any mouse line in which the agent can propagate sufficiently is suitable. An additional requirement at a practical level is the ability to characterize the agent on first passage. In this respect, use of PrP-a mice is preferable because in addition to AR, IP, histopathologic analysis, and PrPSc patterning, WB can also be applied to diagnose BSE. In contrast, its application in PrP-b mice is less informative (33).





These methods can also be applied to analyze bioassay data derived from validated transgenic mouse lines that offer the advantage of higher AR and decreased IP, provided that appropriate transgenic lines are selected and the TSE source and the donor species under investigation are taken into consideration. In this particular instance, our first choices would have been the use of a mouse line overexpressing a bovine transgene in combination with 1 that overexpresses a caprine transgene. At initiation of the study, an established bovinised line was not available to us, and the data generated from the wild-type mice were considered sufficient to identify unequivocally the agent strain. Caprine transgenic mouse lines are still under development and not characterized or widely available. Instead, we used tg338 mice although they show <100% AR and extended IP when inoculated with BSE (26,27). Our data show that this ovinized line offers a feasible alternative for detecting and differentiating caprine TSEs.





The 2 cases of naturally occurring BSE in small ruminants—the 1 reported here and the 1 identified in France (15)—occurred in different countries, during different time periods, and before strict BSE control measures were fully implemented. Therefore, the most likely origin of these 2 cases would be exposure to BSE-contaminated food supplements. Although in France goats constitute 14.3% of the small ruminant population, in the United Kingdom they account for only 0.3% of small ruminants. It is intriguing, therefore, that the only naturally occurring BSE cases in small ruminants in France and particularly in the United Kingdom were detected in goats and not in sheep, although they have also been exposed to contaminated food supplements. A possible explanation could be that goats are generally managed more intensively than sheep and thus might have been exposed to higher doses of the infectious agent because of the more frequent use of concentrates in intensive dairy farming. Similar observations have been reported in cattle, in which the incidence of BSE was significantly higher in dairy herds and in which management is much more intensive than in beef herds (34). In the United Kingdom, most of the commercial goat herds are kept for milk production in a typically intensive production system, similar to dairy cattle.





The BSE case we have confirmed was 1 of 26 historic goat samples examined in the United Kingdom collected during 1984–2002 (16,17). Since 1993, scrapie in goats has been a notifiable disease in the United Kingdom, and since 2005, samples from all suspected cases of TSE in small ruminants are required to be tested for BSE-like features by using WB (19). No BSE cases have been identified, although an intermediate case in a goat was reported and is under investigation by bioassay for final resolution (35,36). This screening of brain samples from all small ruminant cases offers reassurance that BSE is not present in the contemporary small ruminant population. However, application of WB to sheep experimentally co-infected with BSE and scrapie detected only the scrapie agent (37). Also, in contrast to BSE, where infectivity is mainly confined to the nervous system, in small ruminants the BSE agent is widely distributed in peripheral tissues and can be transmitted horizontally (11,38). Therefore, feed ban measures alone would be inadequate to control a BSE outbreak in small ruminants. Also, it would be impossible to prevent BSE from entering the human food chain through consumption of food products derived from small ruminants.





Because TSEs in goats are still a problem, particularly in Mediterranean countries, our data suggest that extensive surveillance and breeding schemes must remain in place to prevent a BSE outbreak in small ruminants and to safeguard public health. This report also highlights several issues regarding the use of mouse bioassay to identify TSE strains. As governing bodies seek confirmation of equivocal cases that are identified worldwide, they must be aware of the limitations, cost, and timescale demands of confirming such cases.





Dr Spiropoulos is a veterinary researcher at Veterinary Laboratories Agency with a particular interest in animal pathology. He is the head of the Mouse Bioassay Team that specializes in pathology of experimental animals. His research interests include neurodegenerative disorders and animal diseases of policy relevance, particularly zoonoses.





Acknowledgments


We thank John Sheehan for tissue retrieval from wax-impregnated tissue blocks; Angel Ortiz-Pelaez for epidemiologic assistance; histopathology employees at Veterinary Laboratories Agency for expert technical support in histopathology and immunohistochemistry; and Animal Services Unit employees at Veterinary Laboratories Agency for expert support with animal procedures and care.





This work was supported by a Department of Environment, Food and Rural Affairs grant (project SE1849).





http://wwwnc.cdc.gov/eid/article/17/12/11-0333_article.htm






Sunday, October 3, 2010

Scrapie, Nor-98 atypical Scrapie, and BSE in sheep and goats North America, who's looking ?


http://nor-98.blogspot.com/2010/10/scrapie-nor-98-atypical-scrapie-and-bse.html





Thursday, November 18, 2010

Increased susceptibility of human-PrP transgenic mice to bovine spongiform encephalopathy following passage in sheep


http://bse-atypical.blogspot.com/2010/11/increased-susceptibility-of-human-prp.html





http://nor-98.blogspot.com/




Sunday, December 12, 2010

EFSA reviews BSE/TSE infectivity in small ruminant tissues News Story 2 December 2010


http://transmissiblespongiformencephalopathy.blogspot.com/2010/12/efsa-reviews-bsetse-infectivity-in.html




Monday, November 22, 2010

Atypical transmissible spongiform encephalopathies in ruminants: a challenge for disease surveillance and control

REVIEW ARTICLES


http://transmissiblespongiformencephalopathy.blogspot.com/2010/11/atypical-transmissible-spongiform.html




Sunday, April 18, 2010

SCRAPIE AND ATYPICAL SCRAPIE TRANSMISSION STUDIES A REVIEW 2010


http://scrapie-usa.blogspot.com/2010/04/scrapie-and-atypical-scrapie.html




Wednesday, January 19, 2011

EFSA and ECDC review scientific evidence on possible links between TSEs in animals and humans Webnachricht 19 Januar 2011


http://transmissiblespongiformencephalopathy.blogspot.com/2011/01/efsa-and-ecdc-review-scientific.html




Tuesday, February 01, 2011

Sparse PrP-Sc accumulation in the placentas of goats with naturally acquired scrapie

http://scrapie-usa.blogspot.com/2011/02/sparse-prp-sc-accumulation-in-placentas.html




Sheep/Goat milk, scrapie-free and or BSE-free ???




Sheep milk, scrapie-free


When consumers perceive a food as unsafe, demand for the food can drop as in the bovine spongiform encephalopathy (BSE) revelations of the 1990s. A European project, Riskscra, has put together comprehensive guidelines for sheep milk producers and the industry as a whole to offer a scrapie-free assurance for ovine milk products.



Sheep milk production is an important part of the dairy products industry in Mediterranean countries. The dairy sheep industry is based on local breeds adapted to the production methods and environment.



Experimental evidence has indicated that BSE is transmissible from cows to sheep through oral and parenteral (other than through the alimentary canal) means. Abnormal prion proteins (PrPs) have been found in the mammary glands of sheep with mastitis and scrapie. The fear is that the scrapie may actually be BSE.



The genetics of scrapie resistance is known inasmuch as the ARQ/ARQ genotype is susceptible to some forms of scrapie and experimental BSE. Presence of the PrP also determines a sheep's resistance or susceptibility to transmissible spongiform encephalopathies (TSE). Genetic selection is used as the main means of scrapie control in the United Kingdom.



Along with initiatives from European institutions to promote TSE resistance in livestock, the EU-funded project Riskscra aimed to develop tools to assess the risk of scrapie in milk. Guidelines and recommendations can be applied by breeders and the dairy industry.



Suitable genetic analysis methods for routine control purposes were researched and drawn up into document form for dairy technicians. 'Guidelines to set up traceability in cheese making factories with associated scrapie risk level' integrates International Advisory Group (IAG) dairy production rules and regulations on PrP allele profile control. Specific training courses were also held for dairy technicians.



To make sure that the results of relevant research reach all levels in the sheep dairy production industry, Riskscra organised cooperation between all players and coordination of national and European policies. Networking of research teams was actively encouraged, particularly by bringing European small and medium-sized enterprises (SMEs) in contact with research centres. The results of this initiative also promise to establish a border-free zone for research and create more jobs in the research sector.



Guidelines developed by Riskscra can be used to implement safety or commercial strategies from scratch as well as to improve existing control systems. The Riskscra control system is particularly relevant to producers, breeder organisations and other institutions interested in controlling the scrapie risk in sheep dairy products. A prime example of appropriate use is its application to the current milk payment criteria based only on non-scrapie–related criteria such as milk quantity and bacterial content.



Improving the quality of dairy products on the market increases the confidence of consumers and constitutes a basis for fair competition among dairy industries across Europe, again with added benefits for consumers. In addition, it enhances European competitiveness on the global market.


Country: ITALY


Information Source: Result from the EU funded FP6-SME programme




Date: 2011-11-25



Contact Details

BONACINA, Cesare (Dr)



ISTITUTO SPERIMENTALE ITALIANO "LAZZARO SPALLANZANI"


Director


MILANO


ITALY




Offer ID: 7435







http://cordis.europa.eu/fetch?CALLER=MSS_IT_OFFR_EN&ACTION=D&DOC=3&CAT=OFFR&QUERY=0133f09c98dd:2ddc:23d0d437&RCN=7435




TO date, and i imphasize 'to date', there has been no documented evidence of transmission of BSE via milk of BSE infected cow to another cow. however, with the limited testing done to date, on just the c-BSE, you cannot rule this out, especially with the atypical BSE L-type i.e. BASE, being much more virulent. Concern has been increasing due to fluids from TSE species i.e. blood, urine, and milk, and the fact that infectivity has been detected. ...tss



Prion infectivity has now been detected in blood, urine and milk.


please see ;


Seven main threats for the future linked to prions

The NeuroPrion network has identified seven main threats for the future linked to prions.

First threat

The TSE road map defining the evolution of European policy for protection against prion diseases is based on a certain numbers of hypotheses some of which may turn out to be erroneous. In particular, a form of BSE (called atypical Bovine Spongiform Encephalopathy), recently identified by systematic testing in aged cattle without clinical signs, may be the origin of classical BSE and thus potentially constitute a reservoir, which may be impossible to eradicate if a sporadic origin is confirmed.

*** Also, a link is suspected between atypical BSE and some apparently sporadic cases of Creutzfeldt-Jakob disease in humans. These atypical BSE cases constitute an unforeseen first threat that could sharply modify the European approach to prion diseases.

Second threat

In small ruminants, a new atypical form of scrapie currently represents up to 50% of detected cases and even involves sheep selected for resistance to classical scrapie. The consequences for animal and human health are still unknown and there may be a potential connection with atypical BSE. These atypical scrapie cases constitute a second threat not envisioned previously which could deeply modify the European approach to prion diseases.

Third threat

The species barrier between human and cattle might be weaker than previously expected and the risk of transmission of prion diseases between different species has been notoriously unpredictable. The emergence of new atypical strains in cattle and sheep together with the spread of chronic wasting disease in cervids renders the understanding of the species barrier critical. This constitutes a third threat not properly envisioned previously that could deeply modify the European approach to prion diseases.

Fourth threat

Prion infectivity has now been detected in blood, urine and milk and this has potential consequences on risk assessments for the environment and food as well as for contamination of surfaces including medical instruments. Furthermore the procedures recommended for decontamination of MBM (Meat and Bone Meal), which are based on older methodologies not designed for this purpose, have turned out to be of very limited efficacy and compromise current policies concerning the reuse of these high value protein supplements (cross-contamination of feed circuits are difficult to control). It should be noted that the destruction or very limited use of MBM is estimated to still cost 1 billion euros per year to the European economy,

whereas other countries, including the US,

Brazil, and Argentine do not have these constraints.

However, many uncertainties remain concerning the guarantees that can be reasonably provided for food and feed safety and scientific knowledge about the causative agents (prions) will continue to evolve. This decontamination and environmental issue is a fourth threat that could modify deeply the European approach to prion diseases.

Fifth threat The precise nature of prions remains elusive. Very recent data indicate that abnormal prion protein (PrPTSE) can be generated from the brains of normal animals, and under some conditions (including contaminated waste water) PrPTSE can be destroyed whereas the BSE infectious titre remains almost unchanged, a finding that underlines the possibility of having BSE without any detectable diagnostic marker. These are just two areas of our incomplete knowledge of the fundamental biology of prions which constitute a fifth threat to the European approach to prion diseases.

Sixth threat The absence of common methods and standardisation in the evaluation of multiple in vivo models with different prion strains and different transgenic mice expressing PrP from different species (different genotypes of cattle, sheep, cervids, etc) renders a complete and comprehensive analysis of all the data generated by the different scientific groups almost impossible. This deeply impairs risk assessment. Moreover, the possibility of generating PrPTSE de novo with new powerful techniques has raised serious questions about their appropriateness for use as blood screening tests. The confusion about an incorrect interpretation of positive results obtained by these methods constitutes a sixth threat to European approach to prion diseases.

Seventh Threat The detection of new or re-emerging prion diseases in animals or humans which could lead to a new crisis in consumer confidence over the relaxation of precautionary measures and surveillance programmes constitutes a seventh threat that could modify the European approach to prion diseases.

http://www.neuroprion.org/en/np-neuroprion.html




Goat BSE: Proposal for Improvement of Goat TSE Discriminative Diagnosis and Susceptibility based Assessment of BSE Infectivity in Goat Milk and Meat

Funded by EU, DEFRA This project is run by a consortium of ten research teams in seven EU countries.

In light of the known ability of the BSE agent to cross the animal/human species barrier, recent evidence establishing the presence of BSE in goat is especially alarming, as it represents a new potential risk of food-born contamination to human consumers of goat milk and meat products. The main objective is to determine the tissue distribution of BSE after oral exposure of goats and to do this while simultaneously generating data on genetic susceptibility in the most common used production breeds. This proposal aims at (i) providing data for the evaluation of human risk associated with goat BSE, (ii) providing pathogenesis data and biological material from first and second passage BSE in goats, (iii) evaluating the possibility of BSE self-maintenance in goat herds through maternal or horizontal transmission, (iv) validating and improving our ability to detect caprine BSE and discriminate it from scrapie in goats. Our approach will establish the influence of PrP gene polymorphisms on scrapie and BSE susceptibility so that genetics could potentially be used for the control of field TSE outbreaks in goats. We will also document European field TSE strain variability in goats by recruiting a large number of TSE goat isolates from affected European countries. Already established or specifically created animal models (strain typing) and biochemical tools (PrPSc typing), will be tested for their ability to efficiently discriminate goat BSE/scrapie. Finally, by measuring infectivity in various tissues collected from goats at different stages of BSE infection, we will provide essential data for quantitative risk assessment.


http://www.roslin.ed.ac.uk/wilfred-goldmann/goat-bse:-proposal-for-improvement-of-goat-tse-discriminative-diagnosis-and-susceptibility-based-assessment-of-bse-infectivity-in-goat-milk-and-meat/




Vet. Res. (2010) 41:48 Original article

Pathogenesis of natural goat scrapie: modulation by host PRNP genotype and effect of co-existent conditions

Lorenzo González1*, Stuart Martin1, Stephen A.C. Hawkins2, Wilfred Goldmann3, Martin Jeffrey1 and Sílvia Sisó1

1 Veterinary Laboratories Agency (VLA-Lasswade), Pentlands Science Park, Penicuik, Midlothian EH26 0PZ, United Kingdom 2 VLA-Weybridge, Addlestone, Surrey KT15 3NB, United Kingdom 3 The Roslin Institute and R(D)SVS University of Edinburgh, Roslin, Midlothian EH25 9PS, United Kingdom

* Corresponding author: l.gonzalez@vla.defra.gsi.gov.uk

Received: 13 January 2010 Accepted: 7 April 2010


Abstract


After detection of a high prevalence of scrapie in a large dairy goat herd, 72 infected animals were examined by immunohistochemistry with prion protein (PrP) antibody Bar224 to study the pathogenesis of the infection. Tissues examined included the brain and thoracic spinal cord (TSC), a wide selection of lymphoreticular system (LRS) tissues, the distal ileum and its enteric nervous system (ENS), and other organs, including the mammary gland. The whole open reading frame of the PRNP gene was sequenced and antibodies to caprine arthritis-encephalitis virus (CAEV) infection were determined. Unexpectedly, accumulation of disease-associated PrP (PrPd) in the brain was more frequent in methionine carriers at codon 142 (24/32, 75.0%) than amongst isoleucine homozygotes (14/40, 35.0%). The latter, however, showed significantly greater amounts of brain PrPd than the former (average scores of 9.3 and 3.0, respectively). A significant proportion of the 38 goats that were positive in brain were negative in the ENS (44.7%) or in the TSC (39.5%). These results, together with the early and consistent involvement of the circumventricular organs and the hypothalamus, point towards a significant contribution of the haematogenous route in the process of neuroinvasion. Chronic enteritis was observed in 98 of the 200 goats examined, with no association with either scrapie infection or presence of PrPd in the gut. Lymphoproliferative interstitial mastitis was observed in 13/31 CAEV-positive and scrapie-infected goats; PrPd in the mammary gland was detected in five of those 13 goats, suggesting a possible contribution of CAEV infection in scrapie transmission via milk.


Key words: scrapie / goat / prion neuroinvasion / transmissible spongiform encephalopathy / CAEV


© The British Crown, published by INRA/EDP Sciences, 2010



http://www.vetres.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/vetres/abs/2010/04/v100001/v100001.html





please see more here ;



http://scrapie-usa.blogspot.com/2010/04/scrapie-and-atypical-scrapie.html




6 January 2010 - The public “TSEs in goats” website Link:


http://www.goatbse.eu/




Since December 2006 a new EU funded project has started that has been essentially developed from NeuroPrion TSEgoat task group members and their progress: “GoatBSE: Proposal for improvement of goat TSE discriminative diagnosis and susceptibility based assessment of BSE infectivity in goat milk and meat.” (European STREP project FOOD-CT-2006-36353, frame work 6, area Thematic priority: Food quality and safety). In this project the focus of study is about consequences of an infection with BSE in goats for disease transmission and product safety.



http://www.neuroprion.org/en/np-news.html






Sheep with Scrapie and Mastitis Transmit Infectious Prions through the Milk?



Ciriaco Ligios1,†, Maria Giovanna Cancedda1, Antonello Carta2, Cinzia Santucciu1, Caterina Maestrale1, Francesca Demontis1, Mariangela Saba1, Cristiana Patta1, James C. DeMartini3, Adriano Aguzzi4,†,* and Christina J. Sigurdson4,5,6,†,*



+ Author Affiliations



1Istituto Zooprofilattico Sperimentale della Sardegna, Sassari, Italy


2Research Unit of Genetics and Biotechnology, DIRPA, AGRIS Sardinia, Olmedo, Italy


3Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado


4Institute of Neuropathology, UniversitätsSpital Zürich, Zürich, Switzerland


5 Department of Pathology, School of Medicine, University of California, San Diego, California


6Department of Pathology, Microbiology, and Immunology, University of California, Davis, California



Next Section



ABSTRACT



Prions are misfolded proteins that are infectious and naturally transmitted, causing a fatal neurological disease in humans and animals. Prion shedding routes have been shown to be modified by inflammation in excretory organs, such as the kidney. Here, we show that sheep with scrapie and lentiviral mastitis secrete prions into the milk and infect nearly 90% of naïve suckling lambs. Thus, lentiviruses may enhance prion transmission, conceivably sustaining prion infections in flocks for generations. This study also indicates a risk of prion spread to sheep and potentially to other animals through dietary exposure to pooled sheep milk or milk products.



http://jvi.asm.org/content/85/2/1136.long




Commentary


In vitro amplification of prions from milk in the detection of subclinical infections


Volume 3, Issue 4 October/November/December 2009 Pages 236 - 239 http://dx.doi.org/10.4161/pri.3.4.10425


Kevin C. Gough, Claire A. Baker, Maged Taema and Ben C. Maddison


View affiliations


Prions can be amplified by serial protein misfolding cyclic amplification (sPMCA) from the milk of a high proportion of apparently healthy, scrapie exposed sheep with PRNP genotypes not previously associated with high disease penetrance1. These data strongly suggest the widespread presence of subclinical scrapie infections within scrapie-exposed flocks containing sheep with a range of susceptible PRNP genotypes. These data also lead to the hypothesis that similar subclinical disease states may be common for other animal and human prion diseases. Furthermore, the application of sPMCA to milk provides a method to detect such subclinical disease. Here, we describe the high level amplification of bovine spongiform encephalopathy (BSE) prions from both ovine and bovine origin, a methodology that will facilitate the detection of any prions secreted within bovine and ovine milk during subclinical and clinical BSE disease.



http://www.landesbioscience.com/journals/prion/article/10425/?nocache=543132411




Prion Protein in Milk


Nicola Franscini,1 Ahmed El Gedaily,1 Ulrich Matthey,1 Susanne Franitza,1 Man-Sun Sy,2 Alexander Bürkle,3 Martin Groschup,4 Ueli Braun,5 and Ralph Zahn1


Conclusions/Significance


In view of a recent study showing evidence of prion replication occurring in the mammary gland of scrapie infected sheep suffering from mastitis, the appearance of PrPC in milk implies the possibility that milk of TSE-infected animals serves as source for PrPSc.



http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1762385/



http://www.allprion.com/Documents/Produkteblatt_PrionProtein.pdf




Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues



Olivier Andréoletti1*, Leonor Orge2, Sylvie L. Benestad3, Vincent Beringue4, Claire Litaise1, Stéphanie Simon5, Annick Le Dur4, Hubert Laude4, Hugh Simmons6, Séverine Lugan1, Fabien Corbière1, Pierrette Costes1, Nathalie Morel5, François Schelcher1, Caroline Lacroux1







Atypical/Nor98 scrapie was first identified in 1998 in Norway. It is now considered as a worldwide disease of small ruminants and currently represents a significant part of the detected transmissible spongiform encephalopathies (TSE) cases in Europe. Atypical/Nor98 scrapie cases were reported in ARR/ARR sheep, which are highly resistant to BSE and other small ruminants TSE agents. The biology and pathogenesis of the Atypical/Nor98 scrapie agent in its natural host is still poorly understood. However, based on the absence of detectable abnormal PrP in peripheral tissues of affected individuals, human and animal exposure risk to this specific TSE agent has been considered low. In this study we demonstrate that infectivity can accumulate, even if no abnormal PrP is detectable, in lymphoid tissues, nerves, and muscles from natural and/or experimental Atypical/Nor98 scrapie cases. Evidence is provided that, in comparison to other TSE agents, samples containing Atypical/Nor98 scrapie infectivity could remain PrPSc negative. This feature will impact detection of Atypical/Nor98 scrapie cases in the field, and highlights the need to review current evaluations of the disease prevalence and potential transmissibility. Finally, an estimate is made of the infectivity loads accumulating in peripheral tissues in both Atypical/Nor98 and classical scrapie cases that currently enter the food chain. The results obtained indicate that dietary exposure risk to small ruminants TSE agents may be higher than commonly believed.





Author Summary

Following the bovine spongiform encephalopathy (BSE) crisis and the identification of its zoonotic properties, a sanitary policy has been implemented based on both eradication of transmissible spongiform encephalopathies (TSE) in food-producing animals and exclusion of known infectious materials from the food chain. Atypical/Nor98 scrapie is a prion disease of small ruminants identified worldwide. Currently it represents a significant part of the TSE cases detected in Europe. The restricted tissue distribution of Atypical/Nor98 scrapie agent in its natural host and the low detected prevalence of secondary cases in affected flocks meant that it is believed to be a poorly transmissible disease. This has led to the view that Atypical/Nor98 scrapie is a spontaneous disorder for which human and animal exposure risk remains low. In this study we demonstrate that in affected individuals, Atypical/Nor98 scrapie agent can disseminate in lymphoid tissues, nerves, and muscles, challenging the idea that it is a brain-restricted infectious agent. Evidence for the deficiencies in the current methods applied for monitoring Atypical/Nor98 scrapie is provided that would indicate an underestimation in the prevalence in the general population and in the affected flocks. These elements challenge the hypothesis on the biology of this recently identified TSE agent.





snip...



Assessing Atypical/Nor98 scrapie transmissibility through oral route in natural host and presence in placenta and in colostrum/milk (which are considered as major sources for TSE transmission between small ruminants) [28], [32] will provide crucial data.



snip...





Citation: Andréoletti O, Orge L, Benestad SL, Beringue V, Litaise C, et al. (2011) Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues. PLoS Pathog 7(2): e1001285. doi:10.1371/journal.ppat.1001285

Editor: David Westaway, University of Alberta, Canada


Received: June 21, 2010; Accepted: January 10, 2011; Published: February 10, 2011

Copyright: © 2011 Andréoletti et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funding: The different parts of this work were funded by (i) The Food Standard Agency (UK) M03058, (ii) the FP7 EU project 'Priority' (243950 FP7-KBBE KBBE-2009-1-2-06), and (iii) Programme opérationnel de Coopération territoriale Espagne - France - Andorre 2007-2013 EFA85/08-COTSA. Lymphoid tissue collection in Portuguese sheep was supported by AGROS 558 (PO AGRO 8.1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

* E-mail: o.andreoletti@envt.fr



http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1001285




Prions in Milk from Ewes Incubating Natural Scrapie


http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1000238




Friday, February 11, 2011

Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues


http://nor-98.blogspot.com/2011/02/atypicalnor98-scrapie-infectivity-in.html




1: J Infect Dis 1980 Aug;142(2):205-8


Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to nonhuman primates.


Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.


Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were exposed to the infectious agents only by their nonforced consumption of known infectious tissues. The asymptomatic incubation period in the one monkey exposed to the virus of kuru was 36 months; that in the two monkeys exposed to the virus of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively. Careful physical examination of the buccal cavities of all of the monkeys failed to reveal signs or oral lesions. One additional monkey similarly exposed to kuru has remained asymptomatic during the 39 months that it has been under observation.


snip...


The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie by natural feeding to squirrel monkeys that we have reported provides further grounds for concern that scrapie-infected meat may occasionally give rise in humans to Creutzfeldt-Jakob disease.

PMID: 6997404


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract




12/10/76

AGRICULTURAL RESEARCH COUNCIL REPORT OF THE ADVISORY COMMITTE ON SCRAPIE

Office Note CHAIRMAN: PROFESSOR PETER WILDY

snip...

A The Present Position with respect to Scrapie A] The Problem Scrapie is a natural disease of sheep and goats. It is a slow and inexorably progressive degenerative disorder of the nervous system and it ia fatal. It is enzootic in the United Kingdom but not in all countries. The field problem has been reviewed by a MAFF working group (ARC 35/77). It is difficult to assess the incidence in Britain for a variety of reasons but the disease causes serious financial loss; it is estimated that it cost Swaledale breeders alone $l.7 M during the five years 1971-1975. A further inestimable loss arises from the closure of certain export markets, in particular those of the United States, to British sheep. It is clear that scrapie in sheep is important commercially and for that reason alone effective measures to control it should be devised as quickly as possible. Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates.


One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasised by the finding that some strains of scrapie produce lesions identical to the once which characterise the human dementias" Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the acrapie problem urgent if the sheep industry is not to suffer grievously.


snip...


76/10.12/4.6


http://web.archive.org/web/20010305223125/www.bseinquiry.gov.uk/files/yb/1976/10/12004001.pdf



Nature. 1972 Mar 10;236(5341):73-4.


Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).


Gibbs CJ Jr, Gajdusek DC. Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0


Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)


C. J. GIBBS jun. & D. C. GAJDUSEK National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland


SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey (Macaca fascicularis) with an incubation period of more than 5 yr from the time of intracerebral inoculation of scrapie-infected mouse brain. The animal developed a chronic central nervous system degeneration, with ataxia, tremor and myoclonus with associated severe scrapie-like pathology of intensive astroglial hypertrophy and proliferation, neuronal vacuolation and status spongiosus of grey matter. The strain of scrapie virus used was the eighth passage in Swiss mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton, Berkshire).


http://www.nature.com/nature/journal/v236/n5341/abs/236073a0.html




Wednesday, February 16, 2011

IN CONFIDENCE

SCRAPIE TRANSMISSION TO CHIMPANZEES

IN CONFIDENCE

http://scrapie-usa.blogspot.com/2011/02/in-confidence-scrapie-transmission-to.html





Sunday, April 18, 2010

SCRAPIE AND ATYPICAL SCRAPIE TRANSMISSION STUDIES A REVIEW 2010

http://scrapie-usa.blogspot.com/2010/04/scrapie-and-atypical-scrapie.html




Monday, April 25, 2011

Experimental Oral Transmission of Atypical Scrapie to Sheep

Volume 17, Number 5-May 2011

http://nor-98.blogspot.com/2011/04/experimental-oral-transmission-of.html





Monday, November 30, 2009

USDA AND OIE COLLABORATE TO EXCLUDE ATYPICAL SCRAPIE NOR-98 ANIMAL HEALTH CODE

http://nor-98.blogspot.com/2009/11/usda-and-oie-collaborate-to-exclude.html




I strenuously urge the USDA and the OIE et al to revoke the exemption of the legal global trading of atypical Nor-98 scrapie TSE. ...TSS




Friday, February 11, 2011

Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues

http://nor-98.blogspot.com/2011/02/atypicalnor98-scrapie-infectivity-in.html




Thursday, July 14, 2011

Histopathological Studies of "CH1641-Like" Scrapie Sources Versus Classical Scrapie and BSE Transmitted to Ovine Transgenic Mice (TgOvPrP4)

http://transmissiblespongiformencephalopathy.blogspot.com/2011/07/histopathological-studies-of-ch1641.html





Monday, June 27, 2011

Comparison of Sheep Nor98 with Human Variably Protease-Sensitive Prionopathy and Gerstmann-Sträussler-Scheinker Disease

http://prionopathy.blogspot.com/2011/06/comparison-of-sheep-nor98-with-human.html





BSE: TIME TO TAKE H.B. PARRY SERIOUSLY

If the scrapie agent is generated from ovine DNA and thence causes disease in other species, then perhaps, bearing in mind the possible role of scrapie in CJD of humans (Davinpour et al, 1985), scrapie and not BSE should be the notifiable disease. ...



http://collections.europarchive.org/tna/20090505194948/http://bseinquiry.gov.uk/files/yb/1988/06/08004001.pdf





Thursday, June 2, 2011



USDA scrapie report for April 2011 NEW ATYPICAL NOR-98 SCRAPIE CASES Pennsylvania AND California



http://nor-98.blogspot.com/2011/06/usda-scrapie-report-for-april-2011-new.html



Monday, June 20, 2011 2011

Annual Conference of the National Institute for Animal Agriculture ATYPICAL NOR-98 LIKE SCRAPIE UPDATE USA

http://nor-98.blogspot.com/2011/06/2011-annual-conference-of-national.html




Monday, June 27, 2011

Comparison of Sheep Nor98 with Human Variably Protease-Sensitive Prionopathy and Gerstmann-Sträussler-Scheinker Disease

http://prionopathy.blogspot.com/2011/06/comparison-of-sheep-nor98-with-human.html





Monday, November 30, 2009

USDA AND OIE COLLABORATE TO EXCLUDE ATYPICAL SCRAPIE NOR-98 ANIMAL HEALTH CODE

http://nor-98.blogspot.com/2009/11/usda-and-oie-collaborate-to-exclude.html




Case report



Atypical/Nor98 scrapie in the Basque Country: a case report of eight outbreaks


Ana B Rodríguez-Martínez1, Joseba M Garrido1, Sonia Maza1, Leyre Benedicto1, Mariví Geijo1, Nieves Gómez1, Esmeralda Minguijón1, Sylvie L Benestad2 and Ramón A Juste1*

* Corresponding author: Ramón A Juste rjuste@neiker.net

Author Affiliations

1 Department of Animal Health. Neiker-Tecnalia, 48160 Derio. Bizkaia. Spain

2 National Veterinary Institute, Department of Pathology, Postboks 750 Sentrum. 0106 Oslo. Norway

For all author emails, please log on.

BMC Veterinary Research 2010, 6:17 doi:10.1186/1746-6148-6-17




The electronic version of this article is the complete one and can be found online at:

http://www.biomedcentral.com/1746-6148/6/17





Received: 6 November 2009
Accepted: 26 March 2010
Published: 26 March 2010




© 2010 Rodríguez-Martínez et al; licensee BioMed Central Ltd.



This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.



Abstract

Background

Since 2002, an active surveillance program for transmissible spongiform encephalopathy in small ruminants in European Union countries allowed identification of a considerable number of atypical cases with similarities to the previously identified atypical scrapie cases termed Nor98.



Case presentation

Here we report molecular and neuropathological features of eight atypical/Nor98 scrapie cases detected between 2002 and 2009. Significant features of the affected sheep included: their relatively high ages (mean age 7.9 years, range between 4.3 and 12.8), their breed (all Latxa) and their PRNP genotypes (AFRQ/ALRQ, ALRR/ALRQ, AFRQ/AFRQ, AFRQ/AHQ, ALRQ/ALRH, ALRQ/ALRQ). All the sheep were confirmed as atypical scrapie by immunohistochemistry and immunoblotting. Two cases presented more PrP immunolabelling in cerebral cortex than in cerebellum.



Conclusions

This work indicates that atypical scrapie constitutes the most common small ruminant transmissible spongiform encephalopathy form in Latxa sheep in the Spanish Basque Country. Moreover, a new genotype (ALRQ/ALRH) was found associated to atypical scrapie.



SNIP...



Case reports from this study and other case reports from Spain http://www.eeb.es/pags/espana.htm webcite and Portugal [35], indicate a high frequency of atypical cases compared to CS outbreaks in the Iberian Peninsula. It could be speculated that AS/Nor98 is the traditional form of scrapie in the Iberian part of the Basque country, whilst in the French part, the classical form has been predominant [59]. This would point to some unidentified epidemiological features limiting the spread of classical scrapie in the Iberian Peninsula. However, since the analysis of all sheep can not be guaranteed, it is difficult to test this hypothesis. The analysis of all sheep would provide more information about the epidemiology and pathology of this disease. Moreover, it could contribute in assessing whether AS is present in the Basque Country with the same high frequencies as others human TSEs, such as sporadic Creutzfeldt-Jakob disease [60] and Fatal Familiar Insomnia compared to other Spanish autonomous communities (National Epidemiology Centre: http:/ / www.isciii.es/ htdocs/ centros/ epidemiologia/ epidemiologia_listado_ecj.jsp webcite).



SEE FULL TEXT ;



http://www.biomedcentral.com/1746-6148/6/17





Peiffer, J. : Gerstmann-Straussler's disease, atypical multiple sclerosis and carcinomas in a family of sheepbreeders. Acta Neuropath. 56: 87-92, 1982. Peiffer (1982) described a family of sheepbreeders in which a father and 2 sons had GSS. All 3 also had congenital hip dysplasia, as did at least 3 other members of the kindred, all females. Atactic symptoms, dysarthria, and personality changes characterized the clinical course of this disorder, which might be labeled atypical multiple sclerosis. Like CJD , GSS is a form of subacute spongiform encephalopathy. Cases of GSS are clinically similar to the atactic type of CJD. Although there are many neuropathologic similarities, GSS differs from CJD by the presence of kuru-plaques and numerous multicentric, floccular plaques in the cerebral and cerebellar cortex, basal ganglia, and white matter. Whereas only 5 to 15% of CJD cases are familial, most cases of GSS are familial.


http://www.mad-cow.org/Alzheimer_cjd.html




Thursday, June 23, 2011


Experimental H-type bovine spongiform encephalopathy characterized by plaques and glial- and stellate-type prion protein deposits



http://transmissiblespongiformencephalopathy.blogspot.com/2011/06/experimental-h-type-bovine-spongiform.html





Saturday, June 25, 2011

Transmissibility of BSE-L and Cattle-Adapted TME Prion Strain to Cynomolgus Macaque


"BSE-L in North America may have existed for decades"


http://transmissiblespongiformencephalopathy.blogspot.com/2011/06/transmissibility-of-bse-l-and-cattle.html





Sunday, June 26, 2011

Risk Analysis of Low-Dose Prion Exposures in Cynomolgus Macaque

http://transmissiblespongiformencephalopathy.blogspot.com/2011/06/risk-analysis-of-low-dose-prion.html




Wednesday, July 06, 2011

Swine Are Susceptible to Chronic Wasting Disease by Intracerebral Inoculation

(see tonnage of mad cow feed in commerce USA...tss)

http://chronic-wasting-disease.blogspot.com/2011/07/swine-are-susceptible-to-chronic.html




Monday, June 27, 2011

Zoonotic Potential of CWD: Experimental Transmissions to Non-Human Primates

http://chronic-wasting-disease.blogspot.com/2011/06/zoonotic-potential-of-cwd-experimental.html




Transmissible Spongiform encephalopathy (TSE) animal and human TSE in North America

14th ICID International Scientific Exchange Brochure -

Final Abstract Number: ISE.114

Session: International Scientific Exchange

Transmissible Spongiform encephalopathy (TSE) animal and human TSE in North America

update October 2009

T. Singeltary

Bacliff, TX, USA

Background:

An update on atypical BSE and other TSE in North America. Please remember, the typical U.K. c-BSE, the atypical l-BSE (BASE), and h-BSE have all been documented in North America, along with the typical scrapie's, and atypical Nor-98 Scrapie, and to date, 2 different strains of CWD, and also TME. All these TSE in different species have been rendered and fed to food producing animals for humans and animals in North America (TSE in cats and dogs ?), and that the trading of these TSEs via animals and products via the USA and Canada has been immense over the years, decades.

Methods:

12 years independent research of available data

Results:

I propose that the current diagnostic criteria for human TSEs only enhances and helps the spreading of human TSE from the continued belief of the UKBSEnvCJD only theory in 2009. With all the science to date refuting it, to continue to validate this old myth, will only spread this TSE agent through a multitude of potential routes and sources i.e. consumption, medical i.e., surgical, blood, dental, endoscopy, optical, nutritional supplements, cosmetics etc.

Conclusion:

I would like to submit a review of past CJD surveillance in the USA, and the urgent need to make all human TSE in the USA a reportable disease, in every state, of every age group, and to make this mandatory immediately without further delay. The ramifications of not doing so will only allow this agent to spread further in the medical, dental, surgical arena's. Restricting the reporting of CJD and or any human TSE is NOT scientific. Iatrogenic CJD knows NO age group, TSE knows no boundaries. I propose as with Aguzzi, Asante, Collinge, Caughey, Deslys, Dormont, Gibbs, Gajdusek, Ironside, Manuelidis, Marsh, et al and many more, that the world of TSE Transmissible Spongiform Encephalopathy is far from an exact science, but there is enough proven science to date that this myth should be put to rest once and for all, and that we move forward with a new classification for human and animal TSE that would properly identify the infected species, the source species, and then the route.

page 114 ;




http://ww2.isid.org/Downloads/14th_ICID_ISE_Abstracts.pdf




International Society for Infectious Diseases Web: http://www.isid.org/




please see full text ;



http://transmissiblespongiformencephalopathy.blogspot.com/




To date the OIE/WAHO assumes that the human and animal health standards set out in the BSE chapter for classical BSE (C-Type) applies to all forms of BSE which include the H-type and L-type atypical forms. This assumption is scientifically not completely justified and accumulating evidence suggests that this may in fact not be the case. Molecular characterization and the spatial distribution pattern of histopathologic lesions and immunohistochemistry (IHC) signals are used to identify and characterize atypical BSE. Both the L-type and H-type atypical cases display significant differences in the conformation and spatial accumulation of the disease associated prion protein (PrPSc) in brains of afflicted cattle. Transmission studies in bovine transgenic and wild type mouse models support that the atypical BSE types might be unique strains because they have different incubation times and lesion profiles when compared to C-type BSE. When L-type BSE was inoculated into ovine transgenic mice and Syrian hamster the resulting molecular fingerprint had changed, either in the first or a subsequent passage, from L-type into C-type BSE. In addition, non-human primates are specifically susceptible for atypical BSE as demonstrated by an approximately 50% shortened incubation time for L-type BSE as compared to C-type. Considering the current scientific information available, it cannot be assumed that these different BSE types pose the same human health risks as C-type BSE or that these risks are mitigated by the same protective measures.



http://www.prionetcanada.ca/detail.aspx?menu=5&dt=293380&app=93&cat1=387&tp=20&lk=no&cat2




Thursday, August 12, 2010

Seven main threats for the future linked to prions

First threat

The TSE road map defining the evolution of European policy for protection against prion diseases is based on a certain numbers of hypotheses some of which may turn out to be erroneous. In particular, a form of BSE (called atypical Bovine Spongiform Encephalopathy), recently identified by systematic testing in aged cattle without clinical signs, may be the origin of classical BSE and thus potentially constitute a reservoir, which may be impossible to eradicate if a sporadic origin is confirmed. ***Also, a link is suspected between atypical BSE and some apparently sporadic cases of Creutzfeldt-Jakob disease in humans. These atypical BSE cases constitute an unforeseen first threat that could sharply modify the European approach to prion diseases.

Second threat

snip...



http://www.neuroprion.org/en/np-neuroprion.html




Subject: SPONGIFORM ENCEPHALOPATHY ADVISORY COMMITTEE Draft minutes of the 100th meeting held on 25th April 2008

Date: July 13, 2008 at 7:16 pm PST


-------------------- BSE-L@LISTS.AEGEE.ORG --------------------




SPONGIFORM ENCEPHALOPATHY ADVISORY COMMITTEE Draft minutes of the 100th meeting held on 25th April 2008



ITEM 2 - APPROVAL OF MINUTES FROM SEAC 99 (SEAC 100/1) 6. The minutes of SEAC 99 were agreed as a correct record with the following amendment: 4 © SEAC 2008 . Paragraph 7, second bullet point, change ".Institute of Animal Health (IAH)." to ".Roslin Institute (RI)." 7. The committee was updated about transmission studies using isolates from a case of Creutzfeldt-Jakob Disease (CJD)1 which had been discussed at SEAC 99. Two lines of transgenic mice expressing the human prion protein gene homozygous for methionine (MM) or valine (VV) at codon 129 and two lines of conventional mice had been inoculated with isolates from the case. Transmission has been more efficient to the humanised mice compared with the conventional mice. The molecular characteristics of the abnormal prion protein (PrPSc) altered on transmission suggesting the patient may have been infected with an unstable TSE strain. Further work was required to characterise the TSE strain. However, it would be difficult to confirm whether this was related to BSE infection unless additional similar cases arose which could be investigated. 8.



snip...



35. Members asked about the spread of chronic wasting disease (CWD) in the USA. Mr Burke replied that CWD was continuing to spread in the cervid population in the USA.



snip...



One sheep in Cyprus, two in the UK and four from France are under investigation for possible BSE infection. Two further BSE cases were identified with unusual transmission properties in a Defra research project (SE1849) and 5 Countries where cases of BSE in cattle were reported in 2007: UK, Austria, Canada, Czech Republic, France, Germany, Hungary, Ireland, Italy, Japan, Poland, Portugal, Slovenia, Slovakia, Spain and The Netherlands. 6 Countries where atypical scrapie in sheep has been reported since 2002: Belgium, Denmark, the Falkland Islands, Finland, France, Germany, Greece, Hungary, Ireland, Italy, The Netherlands, Norway, Portugal, Slovenia, Spain, Sweden, UK and USA. 13 © SEAC 2008 are also subject to further characterisation. BSE has been confirmed in one French goat slaughtered in 2002. A UK goat which was originally diagnosed as a case of scrapie in 1990 is under investigation for possible BSE infection. 37.



snip...



40. Members agreed that the statement should not focus entirely on the risk from BSE. A paragraph should be included to describe the risk that a new zoonotic TSE strain might emerge as a result of the relaxations to TSE controls. The possibility that the transmissibility to humans of such a new strain could be much greater than that of BSE should be acknowledged.



http://www.seac.gov.uk/minutes/final100.pdf




SPONGIFORM ENCEPHALOPATHY ADVISORY COMMITTEE Minutes of the 99th meeting held on 14th December 2007



snip...



ITEM 8 - PUBLIC QUESTION AND ANSWER SESSION 40. The Chair explained that the purpose of the question and answer session was to give members of the public an opportunity to ask questions related to the work of SEAC. Mr Terry Singeltary (Texas, USA) had submitted a question prior to the meeting, asking: "With the Nor-98 now documented in five different states so far in the USA in 2007, and with the two atypical BSE H-base cases in Texas and Alabama, with both scrapie and chronic 14 © SEAC 2007 wasting disease (CWD) running rampant in the USA, is there any concern from SEAC with the rise of sporadic CJD in the USA from ''unknown phenotype'', and what concerns if any, in relations to blood donations, surgery, optical, and dental treatment, do you have with these unknown atypical phenotypes in both humans and animals in the USA? Does it concern SEAC, or is it of no concern to SEAC? Should it concern USA animal and human health officials?" 41.

A member considered that this question appeared to be primarily related to possible links between animal and human TSEs in the USA.

There is no evidence that sCJD is increasing in the USA and no evidence of any direct link between TSEs and CJD in the USA. Current evidence does not suggest that CWD is a significant risk to human health. There are unpublished data from a case of human TSE in the USA that are suggestive of an apparently novel form of prion disease with distinct molecular characteristics. However, it is unclear whether the case had been further characterised, if it could be linked to animal TSEs or if other similar cases had been found in the USA or elsewhere. In relation to the possible public health implications of atypical scrapie, H-type BSE and CWD, research was being conducted to investigate possible links and surveillance was in place to detect any changes in human TSEs. Although possible links between these diseases and human TSEs are of concern and require research, there is no evidence to suggest immediate public health action is warranted. The possible human health risks from classical scrapie had been discussed earlier in the meeting. Members noted that there are effective channels of discussion and collaboration on research between USA and European groups. Members agreed it is important to keep a watching brief on new developments on TSEs.



snip...



http://www.seac.gov.uk/minutes/99.pdf



Monday, October 10, 2011

EFSA Journal 2011 The European Response to BSE: A Success Story

snip...

EFSA and the European Centre for Disease Prevention and Control (ECDC) recently delivered a scientific opinion on any possible epidemiological or molecular association between TSEs in animals and humans (EFSA Panel on Biological Hazards (BIOHAZ) and ECDC, 2011). This opinion confirmed Classical BSE prions as the only TSE agents demonstrated to be zoonotic so far but the possibility that a small proportion of human cases so far classified as "sporadic" CJD are of zoonotic origin could not be excluded. Moreover, transmission experiments to non-human primates suggest that some TSE agents in addition to Classical BSE prions in cattle (namely L-type Atypical BSE, Classical BSE in sheep, transmissible mink encephalopathy (TME) and chronic wasting disease (CWD) agents) might have zoonotic potential.

snip...



http://www.efsa.europa.eu/en/efsajournal/pub/e991.htm?emt=1




http://www.efsa.europa.eu/en/efsajournal/doc/e991.pdf





see follow-up here about North America BSE Mad Cow TSE prion risk factors, and the ever emerging strains of Transmissible Spongiform Encephalopathy in many species here in the USA, including humans ;




http://transmissiblespongiformencephalopathy.blogspot.com/2011/10/efsa-journal-2011-european-response-to.html






Thursday, August 4, 2011

Terry Singeltary Sr. on the Creutzfeldt-Jakob Disease Public Health Crisis, Date aired: 27 Jun 2011

(SEE VIDEO)


http://transmissiblespongiformencephalopathy.blogspot.com/2011/08/terry-singeltary-sr-on-creutzfeldt.html





Sunday, August 21, 2011

The British disease, or a disease gone global, The TSE Prion Disease


(SEE VIDEO)



http://transmissiblespongiformencephalopathy.blogspot.com/2011/08/british-disease-or-disease-gone-global.html




Saturday, March 5, 2011

MAD COW ATYPICAL CJD PRION TSE CASES WITH CLASSIFICATIONS PENDING ON THE RISE IN NORTH AMERICA



http://transmissiblespongiformencephalopathy.blogspot.com/2011/03/mad-cow-atypical-cjd-prion-tse-cases.html





http://transmissiblespongiformencephalopathy.blogspot.com/






price of TSE prion poker goes up again $$$



TSS

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.