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By Chris Clayton, DTN Staff Reporter, and Journal staff Researchers in France and Italy who presented their work at an international conference in London reported two rare strains of bovine spongiform encephalopathy that are harder to detect and affect mainly older cattle. Thierry Baron of the French Food Safety Agency presented research indicating that a 12-year-old Texas cow testing positive for BSE last June, and the 10-year-old Alabama cow that tested positive in March, showed identical testing patterns to a small number of BSE cases in France, Sweden and Poland. Animal scientists are calling such strains "atypical" BSE, which is different from the "typical" BSE caused by cattle eating feed with ruminant offal contaminated with a BSE protein. They don't know whether the atypical strains are caused by something else or simply appear spontaneously in older, susceptible cattle. Art Davis, a U.S. Department of Agriculture scientist for the Animal and Plant Health Inspection Service at the National Veterinary Services Laboratory in Ames, Iowa, said in his presentation Sunday at the London conference that the Texas and Alabama test results showed completely different prion patterns than the Washington state case discovered in December 2003. "The classical lesions were not there," Davis said of the cases. The Washington state cow originated in Alberta, Canada, near where several other BSE cases have been found. The "typical" BSE strain caused a mad cow disease epidemic in Great Britain beginning in the mid-1980s that killed 184,000 cattle and more than 100 people who contracted a human form of the disease caused by eating contaminated beef products. The scientific evidence shows that in almost all cattle cases, the fatal neurological disorder was contracted through contaminated meat and bone meal fed to the cow, typically at a young age. However, scientists finding atypical cases of BSE are beginning to question if there has been a change in the abnormal protein that causes BSE or if cattle might be susceptible to a sporadic BSE affecting older cattle. Danny Matthews, head of transmissible spongiform encephalopathies at England's Veterinary Laboratories Agency, said recent research on atypical cases of BSE raises questions over whether older cattle can sporadically get the disease or if there are more strains of BSE than previously understood. Scientists might also be facing something new, such as "son of BSE," he said. "We don't fully understand what atypical BSE means," Matthews said. "Is it spontaneous or another source causing it? Time will tell." Although the test patterns in the U.S. cases and atypical cases in Europe closely matched, Baron said there were no known links among any of the positive animals. The French Food Safety Agency sent a researcher to the United States to study the positive Texas case and compare its results to known cases in France that did not match the typical BSE positive tests. "You could place them side-by-side and not tell the difference," Baron said. Baron also raised the prospect that the disease could be sporadic in at least a small number of older cattle. He said, however, such a conclusion would be hard to determine because of the small number of cattle with this atypical strain globally. Dr. Sam Holland, South Dakota's state veterinarian, said there are many strains of BSE and varying degrees of infectiousness of the agent. "What if the scenario is there is an atypical prion out there that is much less infective, has a longer incubation period and has not been recognized as part of the Great Britain BSE experience identified in 1985 and '86?" Holland said. "There could be others out there that we haven't recognized yet." He said it is possible the atypical strains are not caused by contaminated feed. He said it still makes sense to continue the ban on ruminant offal in cattle feed to prevent the spread of typical BSE and eventually to eliminate that disease. "Based on what we know about BSE, it makes good sense to, number one, keep some surveillance in place; number two, watch what we import and restrict shipments and movements from places that have had those syndromes; and, number three, with what we know about BSE, it seems to be very prudent to keep our ruminant offal ban in place," Holland said. "At least for typical BSE's, it seems to be very effective. It's probably reasonable to continue the ruminant offal ban even after the last typical BSE case has been eliminated." Editor's note: DTN, a private company based in Omaha, Neb., provides information to agriculture, energy trading markets and other weather-sensitive industries. The Rapid City Journal received a copy of DTN's story and expanded on it. http://www.rapidcityjournal.com/articles/2006/05/31/news/local/news05.txt RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINE - CLASS II ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ END OF ENFORCEMENT REPORT FOR AUGUST 9, 2006 ### look at the table and you'll see that as little as 1 mg (or 0.001 gm) caused 7% (1 of 14) of the cows to come down with BSE; Corinne Ida Lasmézas, Emmanuel Comoy, Stephen Hawkins, Christian Herzog, Franck Mouthon, Timm Konold, Frédéric Auvré, Evelyne Correia, Nathalie Lescoutra-Etchegaray, Nicole Salès, Gerald Wells, Paul Brown, Jean-Philippe Deslys 100 g 10 g 5 g 1 g 100 mg 10 mg 1 mg 0·1 mg 0·01 mg Primate (oral route)* 1/2 (50%) Cattle (oral route)* 10/10 (100%) 7/9 (78%) 7/10 (70%) 3/15 (20%) 1/15 (7%) 1/15 (7%) RIII mice (ic ip route)* 17/18 (94%) 15/17 (88%) 1/14 (7%) PrPres biochemical detection The comparison is made on the basis of calibration of the bovine inoculum used in our study with primates against a bovine brain inoculum with a similar PrPres concentration that was inoculated into mice and cattle.8 *Data are number of animals positive/number of animals surviving at the time of clinical onset of disease in the first positive animal (%). The accuracy of bioassays is generally judged to be about plus or minus 1 log. ic ip=intracerebral and intraperitoneal. Table 1: Comparison of transmission rates in primates and cattle infected orally with similar BSE brain inocula http://www.thelancet.com/journal/journal.isa also have shared Mr Bradley’s surprise at the results because all the dose levels right down to 1 gram triggered infection. 6. It also appears to me that Mr Bradley’s answer (that it would take less than say 100 grams) was probably given with the benefit of hindsight; particularly if one considers that later in the same answer Mr Bradley expresses his surprise that it could take as little of 1 gram of brain to cause BSE by the oral route within the same species. This information did not become available until the "attack rate" experiment had been completed in 1995/96. This was a titration experiment designed to ascertain the infective dose. A range of dosages was used to ensure that the actual result was within both a lower and an upper limit within the study and the designing scientists would not have expected all the dose levels to trigger infection. The dose ranges chosen by the most informed scientists at that time ranged from 1 gram to three times one hundred grams. It is clear that the designing scientists must have also shared Mr Bradley’s surprise at the results because all the dose levels right down to 1 gram triggered infection. [BBC radio 4 FARM news] To cattle: 1 gram of infected brain material (by oral ingestion) In November 2004, USDA announced that its rapid screening test produced an inconclusive BSE test result. A contract laboratory ran its rapid screening test on a brain sample collected for testing and produced three high positive reactive results. As required, the contract laboratory forwarded the inconclusive sample to APHIS’ National Veterinary Services Laboratories (NVSL) for confirmation. NVSL repeated the rapid screening test, which again produced three high positive reactive results. Following established protocol, NVSL ran its confirmatory test, an immunohistochemistry (IHC) test, which was interpreted as negative for BSE. Faced with conflicting results between the rapid screening and IHC tests, NVSL scientists recommended additional testing to resolve the discrepancy but APHIS headquarters officials concluded that no further testing was necessary since testing protocols were followed and the confirmatory test was negative. In our discussions with APHIS officials, they justified their decision to not do additional testing because the IHC test is internationally recognized as the "gold standard" of testing. Also, they believed that USDA/OIG-A/50601-10-KC/ Page iv conducting additional tests would undermine confidence in USDA’s testing protocols. OIG obtained evidence that indicated additional testing was prudent. We came to this conclusion because the rapid screening tests produced six high positive reactive results, the IHC tests conflicted, and various standard operating procedures were not followed. Also, our review of the relevant scientific literature, other countries’ protocols, and discussions with experts led us to conclude that additional confirmatory testing should be considered in the event of conflicting test results. To maintain objectivity and independence, we requested that USDA’s Agricultural Research Service (ARS) perform the Office International des Epizooties (OIE) Scrapie-Associated Fibrils (SAF) immunoblot test. The additional testing produced positive results. To confirm, the Secretary of Agriculture requested that an internationally recognized BSE laboratory in Weybridge, England (Weybridge) perform additional testing. Weybridge conducted various tests, including their own IHC tests and three Western blot tests. The tests confirmed that the cow was infected with BSE. The Secretary immediately directed USDA scientists to work with international experts to develop new protocols that include performing dual confirmatory tests in the event of an inconclusive BSE screening test. We attribute the failure to identify the BSE positive sample to rigid protocols, as well as the lack of adequate quality assurance controls over its testing program. Details of our concerns are discussed in Findings 3 and 4. snip... Section 2. Testing Protocols and Quality Assurance Controls In November 2004, USDA announced that its rapid screening test, Bio-Rad Enzyme Linked Immunosorbent Assay (ELISA), produced an inconclusive BSE test result as part of its enhanced BSE surveillance program. The ELISA rapid screening test performed at a BSE contract laboratory produced three high positive reactive results.40 As required,41 the contract laboratory forwarded the inconclusive sample to the APHIS National Veterinary Services Laboratories (NVSL) for confirmatory testing. NVSL repeated the ELISA testing and again produced three high positive reactive results.42 In accordance with its established protocol, NVSL ran its confirmatory test, an immunohistochemistry (IHC) test, which was interpreted as negative for BSE. In addition, NVSL performed a histological43 examination of the tissue and did not detect lesions44 consistent with BSE. Faced with conflicting results, NVSL scientists recommended additional testing to resolve the discrepancy but APHIS headquarters officials concluded no further testing was necessary because testing protocols were followed. In our discussions with APHIS officials, they justified their decision not to do additional testing because the IHC is internationally recognized as the “gold standard.” Also, they believed that conducting additional tests would undermine confidence in USDA’s established testing protocols. However, OIG obtained evidence that indicated additional testing was prudent to ensure that USDA’s testing protocols were effective in detecting BSE and that confidence in USDA’s testing procedures was maintained. OIG came to this conclusion because the rapid tests produced six high positive reactive results, confirmatory testing conflicted with the rapid test results, and various standard operating procedures were not followed. Also, our review of scientific literature, other country protocols, as well as discussions with internationally recognized experts led us to conclude that confirmatory testing should not be limited when conflicting test results are obtained. To maintain objectivity and independence in our assessment, we requested the USDA Agricultural Research Service (ARS) perform the Office International des Epizooties (OIE) Scrapie-Associated Fibrils (SAF) 40 ELISA test procedures require two additional (duplicate) tests if the initial test is reactive, before final interpretation. If either of the duplicate tests is reactive, the test is deemed inconclusive. 41 Protocol for BSE Contract Laboratories to Receive and Test Bovine Brain Samples and Report Results for BSE Surveillance Standard Operating Procedure (SOP), dated October 26, 2004. 42 The NVSL conducted an ELISA test on the original material tested at the contract laboratory and on two new cuts from the sample tissue. 43 A visual examination of brain tissue by a microscope. 44 A localized pathological change in a bodily organ or tissue. immunoblot.45 ARS performed the test at the National Animal Disease Center because NVSL did not have the necessary equipment46 (ultracentrifuge) to do the test. APHIS scientists observed and participated, as appropriate, in this effort. The additional tests conducted by ARS produced positive results. To confirm this finding, the Secretary requested the internationally recognized BSE reference laboratory in Weybridge, England, (Weybridge) to perform additional confirmatory testing. Weybridge conducted various tests, including their own IHC methods, as well as three Western blot methods. The tests confirmed that the suspect cow was infected with BSE. Also, Weybridge confirmed this case as an unequivocal positive case of BSE on the basis of IHC. As a result of this finding, the Secretary immediately directed USDA scientists to work with international experts to develop a new protocol that includes performing dual confirmatory tests in the event of another inconclusive BSE screening test. Finding 3 Rigid Protocols Reduced the Likelihood BSE Could be Detected APHIS relied on a single test method, as well as a histological examination of tissue for lesions consistent with BSE, to confirm the presence of BSE even though discrepant test results indicated further testing may be prudent. When IHC test results were interpreted as negative, APHIS concluded the sample tested negative for BSE. Subsequent independent tests initiated by OIG using a different testing method, as well as confirmatory testing by Weybridge, determined that the suspect sample was a positive case of BSE. APHIS Declares BSE Sample Negative Despite Conflicting Results When the tissue sample originally arrived at NVSL in November 2004 from the contract lab, NVSL scientists repeated the ELISA screening test and again produced three high positive reactive results. NVSL scientists cut out two sections of the brain sample for IHC testing. One section was used for an experimental procedure that was not part of the confirmatory testing protocol, and the other cut was for normal IHC testing using scrapie for a positive control.47 According to NVSL scientists, the experimental test results were inconclusive but the IHC test was interpreted as negative. The NVSL scientists were concerned with the inconsistencies and conducted 45 The OIE SAF immunoblot is an internationally recognized confirmatory test, often referred to as a Western blot test. There are different types of Western blots; the OIE SAF immunoblot includes enrichment steps taken with the sample prior to the standard Western blot steps. 46 APHIS has now ordered the necessary equipment for NVSL. USDA/OIG-A/50601-10-KC Page 32 47 A positive control is a sample that is known to contain a given disease or react in the test. The sample then can be used to make sure that the test for that disease works properly. In the case of BSE, tissue infected with either scrapie or BSE can serve as a positive control for an IHC test for BSE since both are different forms of the same disease (transmissible spongiform encephalopathy or TSE). another IHC test using BSE as a positive control.48 The test result was also interpreted as negative. Also, according to the NVSL scientists, the histological examination of the tissue did not detect lesions consistent with BSE. After the second negative IHC test, NVSL scientists supported doing additional testing. They prepared a plan for additional tests; if those tests had been conducted, BSE may have been detected in the sample. The additional tests recommended by NVSL scientists, but not approved by APHIS Headquarters officials, were the IHC using other antibodies (IHC testing using different antibodies ultimately produced positive results); IHC testing of additional regions of the brain (the cerebellum tested positive); regular and enriched (OIE-like) Western blots (the obex and cerebellum tested positive); and variable rapid tests (the obex and cerebellum tested positive with two different rapid tests). NVSL officials also recommended that the sample be sent to Weybridge for confirmatory testing (to conduct IHC and OIE Western blot tests). In June 2005, Weybridge conducted IHC testing with three different antibodies, including the antibody used in the United States (tested positive), the OIE Western blot (tested positive), a modified commercial kit Western blot (negative) and the NaPTA49 Western blot (tested positive). We obtained information as to the differing protocols used by other countries. We found that while APHIS determined that additional testing was unnecessary after the IHC test, other countries have used multiple tests to confirm positives. In Japan, for example, all reactive screening test samples are examined by both IHC and a Western blot (different from the OIE SAF immunoblot). In the United Kingdom (U.K.), IHC and Western blot (different from the OIE SAF immunoblot) tests are used for all animals that test positive with a screening test. When IHC and the Western blot fail to confirm a positive rapid test, the U.K. resorts to a third test, the OIE SAF immunoblot. With these procedures in place, both Japan and the U.K. have found BSE cases that were rapid test reactive, IHC negative, and finally confirmed positive with a Western blot. Evidence Indicated Additional Testing Would Be Prudent We also spoke with an internationally recognized BSE expert regarding the advisability of limiting confirmatory testing when conflicting results are obtained. This official expressed concern about limiting confirmatory tests to the IHC despite its status as one of the “gold standard” tests. He advised that the IHC is not one test; it is a test method that can vary significantly in sensitivity from laboratory to laboratory. New antibodies can improve or USDA/OIG-A/50601-10-KC Page 33 48 The NVSL uses scrapie as the positive control as part of its normal IHC testing procedures. Due to the conflicting results between the ELISA and IHC tests, the NVSL conducted another IHC test with BSE as the positive control. Subsequently, the NVSL modified the Confirming Inconclusive Results from BSE Testing Laboratories at the NVSL SOP to show that all IHC tested BSE inconclusive samples from contract laboratories will use BSE as the positive control. 49 Sodium phosphotungstic acid. USDA/OIG-A/50601-10-KC Page 34 reduce sensitivity, as can variations in many of the reagents50 used. He explained that his laboratory had experienced cases where an initial confirmatory IHC test was challenged by either a more extensive IHC test or “…applying a more sensitive immunoblot.” He emphasized the importance of having additional confirmatory testing to resolve discrepant results since there are many variables, and most of the variability appears to be due to test performance of the laboratory. OIG became concerned that APHIS relied on its confirmatory test methods when rapid screening tests produced high positive reactive results six times.51 Also, we found that APHIS did not pursue and/or investigate why the ELISA produced high reactive positives. An official from the manufacturer of the ELISA test kit told us that they requested, but did not receive, information on the inconclusive reported by USDA in November 2004. These officials requested this information in order to understand the reasons for the discrepant results. The Bio-Rad ELISA rapid screening test is internationally recognized as a highly reliable test and is the rapid screening test used for USDA’s surveillance effort. According to APHIS officials, they felt it would be inappropriate to collaborate on the one sample because Bio-Rad is a USDA-APHIS regulated biologics company and only one of several competing manufacturers. To maintain confidence in USDA’s test protocols, it would have been a prudent course of action for USDA to determine why such significant differing results were obtained. The fact that they did not pursue this matter caused concerns relating to testing quality assurance procedures. In this regard, we found lack of compliance with SOPs relating to laboratory proficiency and quality assurance (see Finding 4), and, in this case, the storage of sampled material and reporting of test results. We found that the NVSL did not prepare a report to document its confirmatory testing of the November 2004 sample. The SOP52 states that the BSE network laboratory initiating the inconclusive will receive a report of the case. NVSL officials could not explain why a final report had not been prepared. We also found that the inconclusive sample was frozen prior to IHC confirmatory testing. APHIS protocols state that samples are not to be frozen prior to laboratory submission. The OIE Manual of Diagnostic Tests and Vaccines for Terrestrial Animals states that the tissues for histological or IHC examination are not to be frozen as this will provide artefactual53 lesions that may compromise the identification of vacuolation,54 and/or target site location. Although the sample was frozen, APHIS did not conduct a Western 50 A substance used in a chemical reaction to detect, measure, examine, or produce other substances. 51 The six high positive reactive results were from three tests of the submitted sample (multiple runs of the same test). 52 Confirming Inconclusive Results from Bovine Spongiform Encephalopathy Testing Laboratories at the NVSL SOP, dated August 13, 2004. 53 A structure or feature not normally present but visible as a result of an external agent or action, such as one seen in a microscopic specimen after fixation. 54 A small space or cavity in a tissue. USDA/OIG-A/50601-10-KC Page 35 blot test on the sample. An NVSL official said freezing the sample does not make it unsuitable for IHC. APHIS determined that the sample was suitable for IHC and therefore, in accordance with its SOP, did not conduct a Western blot test. APHIS also handled the December 2003 BSE positive differently than the November 2004 sample. For the December 2003 BSE positive sample, APHIS conducted several confirmatory tests in addition to the IHC testing and histological examination (unlike the November 2004 sample tests, both of these were interpreted as positive). ARS performed two Western blots (Prionics Check Western blot and an ARS developed Western blot). When we questioned why the samples were handled differently, APHIS officials stated that the Western blots were done because the IHC in December 2003 was positive. The additional testing was done to further characterize the case, because it was the first U.S. case; the additional testing was not done to decide whether the case was positive or negative. We discussed our concerns with limiting confirmatory testing, particularly given conflicting results, with the APHIS Administrator and staff in May 2005. He explained that international standards recognized more than one “gold standard” test. In setting up its testing protocols, USDA had chosen one as the confirming test, the IHC test, and stayed with it. APHIS protocols only allow a Western blot in cases where the sample has become unsuitable for IHC tests (e.g., in cases where the brainstem architecture is not evident). International standards, he continued, accept a tissue sample as negative for BSE if its IHC test is negative. Once the test is run in accordance with protocols, additional tests undermine the USDA testing protocol and the surveillance program. He concluded that since APHIS’ protocols accepted the IHC test as confirming the presence or absence of BSE, no further testing was necessary. According to protocol, the tissue sample was determined to have tested negative for BSE. On June 24, 2005, USDA announced that the additional testing by the BSE reference laboratory in England confirmed the presence of BSE in the tissue sample. To obviate the possibility that a future sample would be declared negative and then found positive, the Secretary of Agriculture announced a change to APHIS’ testing protocols that same day. He called for “dual confirmatory tests in the event of another ‘inconclusive’ [reactive] BSE screening test.” He also indicated that he would reinforce proper procedures so that samples will not be frozen, and to spot-check the laboratories to see that they complete reports as required. APHIS issued a SOP on the new confirmatory testing protocols on November 30, 2005. http://www.usda.gov/oig/webdocs/50601-10-KC.pdf TSS 03-025IFA From: Terry S. Singeltary Sr. [flounder9@verizon.net] Sent: Thursday, September 08, 2005 6:17 PM To: fsis.regulationscomments@fsis.usda.gov Subject: [Docket No. 03-025IFA] FSIS Prohibition of the Use of Specified Risk Materials for Human Food and Requirements for the Disposition of Non-Ambulatory Disabled Cattle Greetings FSIS, I would kindly like to submit the following to [Docket No. 03-025IFA] FSIS Prohibition of the Use of Specified Risk Materials for Human Food and Requirements for the Disposition of Non-Ambulatory Disabled Cattle THE BSE/TSE SUB CLINICAL Non-Ambulatory Disabled Cattle Broken bones and such may be the first signs of a sub clinical BSE/TSE Non-Ambulatory Disabled Cattle ; SUB CLINICAL PRION INFECTION MRC-43-00 Issued: Monday, 28 August 2000 NEW EVIDENCE OF SUB-CLINICAL PRION INFECTION: IMPORTANT RESEARCH FINDINGS RELEVANT TO CJD AND BSE P.O. Box 42 Bacliff, Texas USA 77518 9/13/2005 http://www.fsis.usda.gov/OPPDE/Comments/03-025IFA/03-025IFA-2.pdf http://www.fsis.usda.gov/oa/topics/BSE_Peer_Review.pdf Mad Cow Cover-Up: NIH Plans to Destroy Brain Samples of Humans Afflicted with Mad Cow-Like CJDSteve Mitchell of UPI has been providing excellent, ongoing coverage of mad cow and its threats in the US. Here is his latest piece. One more strong piece of evidence of the cover-up ‹ it now deserves that label ‹ of mad cow risks here in the US under an administration beholden to big beef.John Stauber-NIH may destroy human brain collection Medical Sciences Cristina Casalone *, Gianluigi Zanusso , Pierluigi Acutis *, Sergio Ferrari , Lorenzo Capucci , Fabrizio Tagliavini ¶, Salvatore Monaco ||, and Maria Caramelli * Edited by Stanley B. Prusiner, University of California, San Francisco, CA, and approved December 23, 2003 (received for review September 9, 2003) Transmissible spongiform encephalopathies (TSEs), or prion diseases, are mammalian neurodegenerative disorders characterized by a posttranslational conversion and brain accumulation of an insoluble, protease-resistant isoform (PrPSc) of the host-encoded cellular prion protein (PrPC). Human and animal TSE agents exist as different phenotypes that can be biochemically differentiated on the basis of the molecular mass of the protease-resistant PrPSc fragments and the degree of glycosylation. Epidemiological, molecular, and transmission studies strongly suggest that the single strain of agent responsible for bovine spongiform encephalopathy (BSE) has infected humans, causing variant Creutzfeldt-Jakob disease. The unprecedented biological properties of the BSE agent, which circumvents the so-called "species barrier" between cattle and humans and adapts to different mammalian species, has raised considerable concern for human health. To date, it is unknown whether more than one strain might be responsible for cattle TSE or whether the BSE agent undergoes phenotypic variation after natural transmission. Here we provide evidence of a second cattle TSE. The disorder was pathologically characterized by the presence of PrP-immunopositive amyloid plaques, as opposed to the lack of amyloid deposition in typical BSE cases, and by a different pattern of regional distribution and topology of brain PrPSc accumulation. In addition, Western blot analysis showed a PrPSc type with predominance of the low molecular mass glycoform and a protease-resistant fragment of lower molecular mass than BSE-PrPSc. Strikingly, the molecular signature of this previously undescribed bovine PrPSc was similar to that encountered in a distinct subtype of sporadic Creutzfeldt-Jakob disease. C.C. and G.Z. contributed equally to this work. ||To whom correspondence should be addressed. E-mail: salvatore.monaco@mail.univr.it . ##################### Bovine Spongiform Encephalopathy ##################### Subject: USDA, SPONTANEOUS MAD COW DISEASE, THE TOOTH FAIRY AND SANTA CLAUS IF we all believe the BSe that the USDA is trying to put out now about atypical BSE in USA cattle just arising spontaneously, IF USA scrapie transmitted to USA cattle long ago in experiments in a lab in Mission Texas did not produce UK BSE, THERE are over 20 strains of scrapie, plus the atypical in sheep, and these strains are increasing in numbers. SCRAPIE, CWD, AND TSE IN CATTLE i.e. ANIMAL TSE RAMPANT IN USA FOR DECADES, and amplified via rendering and NO test tube TSE by either Prusiner or Soto, to date, have ever produced a TSE identical to the sporadic CJD. IN fact, IF you feed BSE tainted materials to cattle and primate, you have BSE and nvCJD. USA is in a very unique situation. there are more documented TSE in different species than any other country, IF, the spontaneous TSE was true, then this would be Prusiner and everyone else that is trying to cash in on this agent with How many more will become exposed and have to die $ Cristina Casalone *, Gianluigi Zanusso , Pierluigi Acutis *, Sergio Ferrari , Lorenzo Capucci , Fabrizio Tagliavini ¶, Salvatore Monaco ||, and Maria Caramelli * Transmissible spongiform encephalopathies (TSEs), or prion diseases, are mammalian neurodegenerative disorders characterized by a posttranslational conversion and brain accumulation of an insoluble, protease-resistant isoform (PrPSc) of the host-encoded cellular prion protein (PrPC). Human and animal TSE agents exist as different phenotypes that can be biochemically differentiated on the basis of the molecular mass of the protease-resistant PrPSc fragments and the degree of glycosylation. Epidemiological, molecular, and transmission studies strongly suggest that the single strain of agent responsible for bovine spongiform encephalopathy (BSE) has infected humans, causing variant Creutzfeldt-Jakob disease. The unprecedented biological properties of the BSE agent, which circumvents the so-called "species barrier" between cattle and humans and adapts to different mammalian species, has raised considerable concern for human health. To date, it is unknown whether more than one strain might be responsible for cattle TSE or whether the BSE agent undergoes phenotypic variation after natural transmission. Here we provide evidence of a second cattle TSE. The disorder was pathologically characterized by the presence of PrP-immunopositive amyloid plaques, as opposed to the lack of amyloid deposition in typical BSE cases, and by a different pattern of regional distribution and topology of brain PrPSc accumulation. In addition, Western blot analysis showed a PrPSc type with predominance of the low molecular mass glycoform and a protease-resistant fragment of lower molecular mass than BSE-PrPSc. Strikingly, the molecular signature of this previously undescribed bovine PrPSc was similar to that encountered in a distinct subtype of sporadic Creutzfeldt-Jakob disease. C.C. and G.Z. contributed equally to this work. ||To whom correspondence should be addressed. E-mail: salvatore.monaco@mail.univr.it. : J Infect Dis 1980 Aug;142(2):205-8 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. PMID: 6997404 snip... snip... WE interviewed officials at five laboratories that test for rabies. Those officials CONFIRMED THEY ARE NOT REQUIRED TO SUBMIT RABIES-NEGATIVE SAMPLES TO APHIS FOR BSE TESTING. A South Dakota laboratory official said they were not aware they could submit rabies-negative samples to APHIS for BSE testing. A laboratory official in another State said all rabies-negative cases were not submitted to APHIS because BSE was ''NOT ON THEIR RADAR SCREEN." Officials from New York, Wisconsin, TEXAS, and Iowa advised they would NOT submit samples from animals they consider too young. Four of the five States contacted defined this age as 24 months; Wisconsin defined it as 30 months. TEXAS officials also advised that they do not always have sufficient tissue remaining to submit a BSE sample. ... snip... HUMAN TSE USA 2005 Bovine Spongiform Encephalopathy (BSE) is a prion Compelling evidence indicates that BSE can be Chronic Wasting Disease (CWD) is a prion disease of elk p.s. please note the 47 PENDING CASES to Sept. 2005 p.s. please note the 2005 Prion D. total 120(8) p.s. please note sporadic CJD 2002(1) 1=3 TYPE UNKNOWN??? p.s. please note 2004 prion disease (6) 6=7 TYPE snip... http://www.bseinquiry.gov.uk/files/yb/1991/01/04004001.pdf snip...end http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf Location: Virus and Prion Diseases of Livestock Project Number: 3625-32000-073-07 Start Date: Sep 15, 2004 Objective: Approach: http://www.bseinquiry.gov.uk/report/volume2/chaptea3.htm#820543 http://www.bseinquiry.gov.uk/report/volume2/chaptea3.htm#820546 3.58 There are several possible reasons why the experiment was not performed Chair: Dr. Jim Logan, Cheyenne, WY Vice Chair: Dr. Joe D. Ross, Sonora, TX Dr. Deborah L. Brennan, MS; Dr. Beth Carlson, ND; Dr. John R. Clifford, DC; Dr. Thomas F. Conner, OH; Dr. Walter E. Cook, WY; Dr. Wayne E. Cunningham, CO; Dr. Jerry W. Diemer, TX; Dr. Anita J. Edmondson, CA; Dr. Dee Ellis, TX; Dr. Lisa A. Ferguson, MD; Dr. Keith R. Forbes, NY; Dr. R. David Glauer, OH; Dr. James R. Grady, CO; Dr. William L. Hartmann, MN; Dr. Carolyn Inch, CAN; Dr. Susan J. Keller, ND; Dr. Allen M. Knowles, TN; Dr. Thomas F. Linfield, MT; Dr. Michael R. Marshall, UT; Dr. Cheryl A. Miller, In; Dr. Brian V. Noland, CO; Dr. Charles Palmer, CA; Dr. Kristine R. Petrini, MN; Mr. Stan Potratz, IA; Mr. Paul E. Rodgers, CO; Dr. Joan D. Rowe, CA; Dr. Pamela L. Smith, IA; Dr. Diane L. Sutton, MD; Dr. Lynn Anne Tesar, SD; Dr. Delwin D. Wilmot, NE; Dr. Nora E. Wineland, CO; Dr. Cindy B. Wolf, MN. The Committee met on November 9, 2005, from 8:00am until 11:55am, Hershey Lodge and Convention Center, Hershey, Pennsylvania. The meeting was called to order by Dr. Jim Logan, chair, with vice chairman Dr. Joe D. Ross attending. There were 74 people in attendance. The Scrapie Program Update was provided by Dr. Diane Sutton, National Scrapie Program Coordinator, United States Department of Agriculture (USDA), Animal and Plant Health Inspection Services (APHIS), Veterinary Services (VS). The complete text of the Status Report is included in these Proceedings. Dr. Patricia Meinhardt, USDA-APHIS-VS-National Veterinary Services Laboratory (NVSL) gave the Update on Genotyping Labs and Discrepancies in Results. NVSL conducts investigations into discrepancies on genotype testing results associated with the Scrapie Eradication Program. It is the policy of the Program to conduct a second genotype test at a second laboratory on certain individual animals. Occasionally, there are discrepancies in those results. The NVSL conducts follow-up on these situations through additional testing on additional samples from the field and archive samples from the testing laboratories. For the period of time from January 1, 2005, until October 15, 2005, there were 23 instances of discrepancies in results from 35 flocks. Of those 23 instances, 14 were caused by laboratory error (paperwork or sample mix-up), 3 results from field error, 5 were not completely resolved, and 1 originated from the use of a non-approved laboratory for the first test. As a result of inconsistencies, one laboratory’s certification was revoked by APHIS-VS. snip... Infected and Source Flocks As of September 30, 2005, there were 105 scrapie infected and source flocks. There were a total of 165** new infected and source flocks reported for FY 2005. The total infected and source flocks that have been released in FY 2005 was 128. The ratio of infected and source flocks cleaned up or placed on clean up plans vs. new infected and source flocks discovered in FY 2005 was 1.03 : 1*. In addition 622 scrapie cases were confirmed and reported by the National Veterinary Services Laboratories (NVSL) in FY 2005, of which 130 were RSSS cases. Fifteen cases of scrapie in goats have been reported since 1990. The last goat case was reported in May 2005. Approximately 5,626 animals were indemnified comprised of 49% non-registered sheep, 45% registered sheep, 1.4% non-registered goats and 4.6% registered goats. Regulatory Scrapie Slaughter Surveillance (RSSS) RSSS was designed to utilize the findings of the Center for Epidemiology and Animal Health (CEAH) Scrapie: Ovine Slaughter Surveillance (SOSS) study. The results of SOSS can be found at http://www.aphis.usda.gov/vs/ceah/cahm/Sheep/sheep.htm . RSSS started April 1, 2003. It is a targeted slaughter surveillance program which is designed to identify infected flocks for clean-up. During FY 2005 collections increased by 32% overall and by 90% for black and mottled faced sheep improving overall program effectiveness and efficiency as demonstrated by the 26% decrease in percent positive black faced sheep compared to FY 2004. Samples have been collected from 62,864 sheep since April 1, 2003, of which results have been reported for 59,105 of which 209 were confirmed positive. During FY 2005, 33,137 samples were collected from 81 plants. There have been 130 NVSL confirmed positive cases (30 collected in FY 2004 and confirmed in FY 2005 and 100 collected and confirmed in FY 2005) in FY 2005. Face colors of these positives were 114 black, 14 mottled, 1 white and 1 unknown. The percent positive by face color is shown in the chart below. Scrapie Testing In FY 2005, 35,845 animals have been tested for scrapie: 30,192 RSSS; 4,742 regulatory field cases; 772 regulatory third eyelid biopsies; 10 third eyelid validations; and 129 necropsy validations (chart 9). Animal ID As of October 04, 2005, 103,580 sheep and goat premises have been assigned identification numbers in the Scrapie National Generic Database. Official eartags have been issued to 73,807 of these premises. *This number based on an adjusted 12 month interval to accommodate the 60 day period for setting up flock plans. Proc. Natl. Acad. Sci. USA, 10.1073/pnas.0502296102 A newly identified type of scrapie agent can naturally infect sheep with resistant PrP genotypes ( sheep prion | transgenic mice ) Annick Le Dur *, Vincent Béringue *, Olivier Andréoletti , Fabienne Reine *, Thanh Lan Laï *, Thierry Baron , Bjørn Bratberg ¶, Jean-Luc Vilotte ||, Pierre Sarradin **, Sylvie L. Benestad ¶, and Hubert Laude * Scrapie in small ruminants belongs to transmissible spongiform encephalopathies (TSEs), or prion diseases, a family of fatal neurodegenerative disorders that affect humans and animals and can transmit within and between species by ingestion or inoculation. Conversion of the host-encoded prion protein (PrP), normal cellular PrP (PrPc), into a misfolded form, abnormal PrP (PrPSc), plays a key role in TSE transmission and pathogenesis. The intensified surveillance of scrapie in the European Union, together with the improvement of PrPSc detection techniques, has led to the discovery of a growing number of so-called atypical scrapie cases. These include clinical Nor98 cases first identified in Norwegian sheep on the basis of unusual pathological and PrPSc molecular features and "cases" that produced discordant responses in the rapid tests currently applied to the large-scale random screening of slaughtered or fallen animals. Worryingly, a substantial proportion of such cases involved sheep with PrP genotypes known until now to confer natural resistance to conventional scrapie. Here we report that both Nor98 and discordant cases, including three sheep homozygous for the resistant PrPARR allele (A136R154R171), efficiently transmitted the disease to transgenic mice expressing ovine PrP, and that they shared unique biological and biochemical features upon propagation in mice. These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health. Author contributions: H.L. designed research; A.L.D., V.B., O.A., F.R., T.L.L., J.-L.V., and H.L. performed research; T.B., B.B., P.S., and S.L.B. contributed new reagents/analytic tools; V.B., O.A., and H.L. analyzed data; and H.L. wrote the paper. A.L.D. and V.B. contributed equally to this work. To whom correspondence should be addressed. Hubert Laude, E-mail: laude@jouy.inra.fr www.pnas.org/cgi/doi/10.1073/pnas.0502296102 snip... A The Present Position with respect to Scrapie Scrapie is a natural disease of sheep and goats. It is a slow The field problem has been reviewed by a MAFF working group It is clear that scrapie in sheep is important commercially and Recently the question has again been brought up as to whether Whether true or not. the hypothesis that these agents might be snip... 76/10.12/4.6 http://www.bseinquiry.gov.uk/files/yb/1976/10/12004001.pdf Most doctors believe that sCJD is caused by a prion protein deforming by Now scientists in France have stumbled across new evidence that adds weight The complete article is 889 words long. full text; http://www.newscientist.com/article.ns?id=mg16922840.300 Edited by D. Carleton Gajdusek, Centre National de la Recherche There is substantial scientific evidence to support the notion that bovine http://www.aphis.usda.gov/vs/nahps/cwd/ USDA CWD MAP (slow to update) http://www.aphis.usda.gov/vs/nahps/cwd/cwd-distribution.html WYOMING GAME AND FISH DEPARTMENT CHRONIC WASTING DISEASE MANAGEMENT PLAN February 17, 2006 REVISED DRAFT 1Department of Microbiology, Immunology and Molecular Genetics, 2Sanders *These authors contributed equally to this work. †Present address: Department of Infectology, Scripps Research Institute, ‡Present address: Institute of Neuropathology, University of Zurich, §To whom correspondence should be addressed: E-mail: gtell2@uky.edu Prions are transmissible proteinaceous agents of mammals that cause fatal To test whether skeletal muscle of diseased cervids contained prion Our results show that skeletal muscle as well as CNS tissue of deer with CWD While the risk of exposure to CWD infectivity following consumption of References and Notes 1. P. J. Bosque et al., Proc. Natl. Acad. Sci. U.S.A. 99, 3812 (2002). 2. S. R. Browning et al., J. Virol. 78, 13345 (2004). 3. A. Buschmann, M. H. Groschup, J. Infect. Dis. 192, 934 (2005). 4. O. Andreoletti et al., Nat. Med. 10, 591 (2004). 5. T. R. Spraker et al., Vet. Pathol. 39, 110 (2002). 6. A. N. Hamir, J. M. Miller, R. C. Cutlip, Vet. Pathol. 41, 78 (2004). 7. S. B. Prusiner et al., Biochemistry 21, 4883 (1980). 8. M. Prinz et al., Am. J. Pathol. 162, 1103 (2003). 9. This work was supported by grants from the U.S. Public Health Service Supporting Online Material www.sciencemag.org/ Materials and Methods Fig. S1 21 November 2005; accepted 13 January 2006 Published online 26 January 2006; Inocula Incubation time, mean d ± SEM (n/n0)* Skeletal muscle Brain CWD-affected deer H92 360 ± 2 d (6/6) 283 ± 7 d (6/6) 33968 367 ± 9 d (8/8) 278 ± 11 d (6/6) 5941 427 ± 18 d (7/7) D10 483 ± 8 d (8/8) 231 ± 17 d (7/7) D08 492 ± 4 d (7/7) Averages 426 d 264 d Non-diseased deer FPS 6.98 >523 d (0/6) FPS 9.98 >454 d (0/7) >454 d (0/6) None >490 d (0/6) PBS >589 d (0/5) *The number of mice developing prion disease divided by the original number Prions in Skeletal Muscles of Deer with Chronic Wasting Disease Rachel C. Angers, Shawn R. Browning, Tanya S. Seward, Christina J. Michael W. Miller, Edward A. Hoover, Glenn C. Telling§ §To whom correspondence should be addressed: E-mail: gtell2@uky.edu Published 26 January 2006 on Science Express DOI: 10.1126/science.1122864 This PDF file includes: Materials and Methods Fig. S1 Supporting Online Materials Materials and Methods Homogenates of semitendinosus/semimembranosus muscle (10% w/v in phosphate buffered saline) were prepared from five emaciated and somnolent mule deer, infected with CWD at the Colorado Division of Wildlife, Wildlife Research These deer were identified as D10, D08, 33968, H92, and 5941. CWD infection confirmed in all cases by the presence of histologic lesions in the brain spongiform degeneration of the perikaryon, the immunohistochemical detection disease-associated PrP in brain and tonsil, or by immunoblotting of disease associated PrP (CerPrPSc). Semitendinosus/semimembranosus muscle was obtained from two asymptomatic, mock inoculated deer, referred to as FPS that originated from a CWD non-endemic area and which were held indoors at State University from ten days of age. These control deer were confirmed CWD by histopathological and immunohistochemical analysis of brain tissue at The utmost care was taken to avoid inclusion of obvious nervous tissue when biopsies were prepared and to ensure that contamination of skeletal muscle CNS tissue did not occur. Fresh, single-use instruments were used to collect biopsy and a central piece from each sample was prepared with fresh, instruments to further isolate muscle tissue for inoculum preparation. Brain transmission were prepared separately from muscle as additional insurance contamination. 1 Groups of anesthetized Tg(CerPrP)1536 mice were inoculated intracerebrally of 1 % skeletal muscle or brain extracts prepared in phosphate buffered Inoculated Tg(CerPrP) mice were diagnosed with prion disease following the development of at least three neurologic symptoms including truncal ataxia, loss of extensor reflex, difficultly righting, and slowed movement. The time inoculation to the onset of clinical signs is referred to as the incubation For PrP analysis in brain extracts of Tg(CerPrP)1536 mice, 10 % homogenates in PBS were either untreated (-) or treated (+) with 40 µg/ml proteinase K hour at 37oC in the presence of 2% sarkosyl. Proteins were separated by sulfate polyacrylamide gel electrophoresis, analyzed by immunoblotting using monoclonal antibody 6H4 (Prionics AG, Switzerland), incubated with secondary antibody, developed using ECL-plus detection (Amersham), and using a FLA-5000 scanner (Fuji). 2 Fig. S1 PrP in brain extracts from representative Tg(CerPrP)1536 mice receiving tissue inocula from CWD-affected or CWD-negative deer. Extracts were either (+) or untreated (-) with proteinase K (PK) as indicated. The positions of molecular weight markers at 21.3, 28.7, 33.5 kDa (from bottom to top) are left of the immunoblot. 3 Chronic Wasting Disease and Potential Transmission to Humans Suggested citation for this article: Belay ED, Maddox RA, Williams ES, Miller MW, Gambetti P, Schonberger LB. Chronic wasting disease and potential transmission to humans. Emerg Infect Dis [serial on the Internet]. 2004 Jun [date cited]. Available from: http://www.cdc.gov/ncidod/EID/vol10no6/03-1082.htm Environmental Sources of Prion Transmission in Mule Deer Suggested citation for this article: Miller MW, Williams ES, Hobbs NT, Wolfe LL. Environmental sources of prion transmission in mule deer. Emerg Infect Dis [serial on the Internet]. 2004 Jun [date cited]. Available from: http://www.cdc.gov/ncidod/EID/vol10no6/04-0010.htm UKBSEnvCJD only theory Singeltary et al 2006 Terry S. Singeltary Sr.
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