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From: TSS ()
Wyo. flock to be killed, tested after scrapie found CHEYENNE - Somewhere near Moorcroft, in an unincorporated area of northeastern Wyoming, a livestock owner will hand over his entire flock of sheep next week to the federal government for a mass execution. The rancher knows what will happen: his herd of roughly 300 sheep will be transported live out of state and taken to a slaughter plant where they will be euthanized, their brains and lymph node tissue harvested for testing. He'll lose his herd because he owned the first U.S. sheep to test positive for a rare strain of scrapie _ a disease found in sheep and goats that's similar to mad cow disease in cattle and chronic wasting disease in sheep and elk. Still, state statute prohibits officials from releasing the rancher's identity, and attempts by The Associated Press to reach him were unsuccessful. Scrapie itself is rare in the United States. Out of more than 115,000 animals tested since 2003, only 300 have tested positive; federal officials hope to eliminate scrapie from U.S. herds by the end of 2010. But the Wyoming rancher's case is even more rare: Fewer than 300 cases worldwide have been recorded of the "Nor98-like" strain of scrapie, so-named because it was first diagnosed in Norway in 1998. "This is very unusual," Larry Cooper, regional spokesman in Fort Collins, Colo., for Animal Plant Health Inspection Service, or APHIS, said of the first discovery of a Nor98-like strain of scrapie in the U.S. "It doesn't indicate that we're going to have mass outbreaks of this particular strain, it just indicates that one of these animals from Europe ended up in our system." There are no known human health risks associated with scrapie. Cooper and Bryce Reece, executive vice president of the Wyoming Wool Growers Association, say consumers and livestock owners have nothing to fear from the diagnosis. "From an industry standpoint, we're not at all concerned or alarmed by it," Reece said. "It's more of an interest to the researchers or the scientists than it is to the industry. I'm sure they're all questioning themselves as to how it got here." Dr. Mark Hall, head of the special pathology section of the National Veterinary Services Laboratories in Ames, Iowa, agreed. "It is something of interest and something I think we want to continue to look at," Hall said. "But this is certainly not a shocking revelation or anything like that. At this point, I don't think there's any evidence that there's any great need for concern." Scrapie experts and Animal Plant Health Inspection Service officials say it's discovery is actually something to brag about. "It means our surveillance system is working," Dr. Diane Sutton, National Scrapie Program coordinator, said. "We found it utilizing our current technologies to find scrapie cases in the United States." APHIS notified the state last month that the sheep rancher's ewe tested positive for a form of scrapie consistent with the Nor98 strain. The ewe was slaughtered in Michigan last fall as part of the USDA's regular scrapie slaughter surveillance program and traced back to the Wyoming flock. Dr. Walt Cook, acting state veterinarian, said the government would pay the livestock owner an indemnity fee based on fair market value for the sheep, before "depopulating" the herd. "It's the best and the simplest thing to do," Cook said. "It's unfortunate to put down all those sheep, but it will allow us to test them and make sure no other animals are infected." Cook and Sutton said the infected ewe's owner had one other option: to quarantine his flock, during which time he couldn't sell breeding animals for several years while the flock was monitored to ensure no other cases of the disease appeared. "Economically it doesn't make much difference one way or the other," Cook said of the rancher's options. "Obviously, by depopulating, he has to go through the loss of his animals, which can be distressful." Reece said when traditional scrapie is found in a flock, typically up to 10 percent of the rest of that herd can be infected with the disease. But with Nor98, when one case is found, to date it has been the only one found in the flock. "I would bet we're not gonna see another one of these in Wyoming, and maybe not even in the United States, but who knows?" Reece said. "With 300 cases worldwide, it's not something out there that's highly transmittable." He said that if an animal becomes infected with scrapie, it will die from it: "It's 100 percent fatal, and because it's 100 percent fatal it's a self-limiting disease." "From a practical standpoint, scrapie is nothing," Reece said. "Pneumonia probably kills more sheep than anything else out there, but because of scrapie's similarities to mad cow disease, from a marketing and consumer standpoint it is important for the U.S. to eradicate the disease from the U.S." Cooper said the effects of Nor98 are basically the same as those seen in classic scrapie _ the disease attacks the central nervous system of infected animals, causing behavioral changes such as tremors of the head and neck. Classical scrapie is believed to be primarily transmitted through exposure to placenta and birth fluids from infected animals or from facilities in which infected animals have lambed. The lamb and wool production business is a $50 million-a-year industry in Wyoming, according to Reece, and a $500 million-a-year industry nationally. According to Cooper, many sheep-importing countries require that the U.S. be free of scrapie for seven years before they'll import U.S. breeding sheep. Subject: NOR98-LIKE STRAIN OF SCRAPIE FOUND IN WYOMING PRESS RELEASE March 16, 2007 Wyoming Livestock Board 2020 Carey Avenue 4th Floor Cheyenne, Wyoming 82002 For more information contact: Dr. Walter Cook at (307) 631-2974 [weekend] or (307) 777-6443 [weekday] *****FOR IMMEDIATE RELEASE***** NOR98-LIKE STRAIN OF SCRAPIE FOUND IN WYOMING CHEYENNE, Wyo. - On Friday, March 16, 2007, the Wyoming Livestock Board (WLSB) was notified by officials of the USDA Animal Plant Health Inspection Service (APHIS) that an adult female sheep had tested positive for a form of scrapie consistent with the Nor98 strain. The ewe was slaughtered in Michigan, where it was tested as part of USDA’s regulatory scrapie slaughter surveillance program and traced back to a flock in Wyoming. The results of this case are distinctly different from those seen for bovine spongiform encephalopathy (BSE) or classical scrapie. Scrapie is a transmissible spongiform encephalopathy and falls into the same category of diseases as chronic wasting disease, found in deer and elk, and bovine spongiform encephalopathy, found in cattle. The disease is limited to sheep and goats and takes years to affect an animal after it has been infected. Scrapie causes sheep to itch and scratch (scrape) wool off, change their behavior and lose body condition; it ultimately ends in death. Nor98-like scrapie differs from classical scrapie in the distribution of brain lesions and in the course of disease progression and epidemiology. Some sheep that are genetically resistant to the classic form of the disease may be susceptible to the Nor98-like strain. Oddly, Nor98-like scrapie is usually diagnosed during surveillance in animals without clinical signs. There are no known human health risks associated with either form of scrapie. This is the first time a Nor98-like strain of scrapie has been documented in the United States. It gets the "Nor98-like" name because it is similar to a case first diagnosed in Norway in 1998. This strain of scrapie is a rare disease even in Europe. Since 1998, fewer than 300 cases have been diagnosed in all of Europe. It is usually seen in single animals and does not tend to become widespread in a flock. In contrast, in flocks infected by classical scrapie typically more than 10 percent of the genetically susceptible animals test positive. "This provides evidence that the surveillance program is working," said Bryce Reece, executive director of the Wyoming Wool Growers Association. "It also indicates that the program is on the cutting-edge of science to detect such a rare disease during standard surveillance." The Wyoming Livestock Board does not expect the Nor98-like strain of scrapie to become a major disease problem for the sheep industry in Wyoming. Risk is limited because diagnosis of Nor98-like scrapie is usually an incidental event, with even highly-exposed flock mates of the positive animal normally unaffected. The infected ewe lambed in it in what is considered a low-risk, range-lambing environment. Nonetheless, the WLSB, APHIS and the Wyoming Wool Growers Association plan to assertively pursue this case to make sure that this strain of scrapie is extinguished and does not establish itself in the U.S. The agencies continue to encourage producers to monitor their sheep for signs of scrapie and other diseases, and to notify their veterinarian if they discover anything unusual. The positive ewe was purchased as an adult within the last several years and moved to a Wyoming flock near the Black Hills. The producer was notified and his flock quarantined as a precautionary measure. An epidemiologic investigation is ongoing and the producer has been cooperative. The case fits the pattern found in Europe - a single, older sheep that was not exhibiting clinical signs of scrapie. The regulatory scrapie slaughter surveillance program is a targeted slaughter surveillance program for sheep and goats designed to identify infected animals and flocks. USDA is conducting this surveillance as part of a program to eradicate scrapie from the United States by the end of 2010. Reece said that the sheep industry supports this program and is committed to eliminating scrapie from the United States. ### FOIA REQUEST FOR ATYPICAL TSE INFORMATION ON VERMONT SHEEP http://lists.ifas.ufl.edu/cgi-bin/wa.exe?A2=ind0704&L=sanet-mg&T=0&P=816 Published online before print October 20, 2005 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 Evidence of a molecular barrier limiting G.J. Raymond1, A. Bossers2, L.D. Raymond1, K.I. O?Rourke3, 1NIAID/NIH Rocky Mountain Laboratories, Hamilton, MT 59840, Abstract Chronic wasting disease (CWD) is a transmissible snip... Clearly, it is premature to draw firm conclusions about CWD snip... http://www.emboj.org/current.shtml Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC. Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of This patient had worked with sheep and human dura mater from 1968 to 1972. It is tempting to speculate that prions were transmitted to this patient 2. Schoene WC, Masters CL, Gibbs CJ Jr, et al. Transmissible spongiform 3. Gorman DG, Benson DF, Vogel DG, Vinters HV. Creutzfeldt-Jakob disease in 4. Miller DC. Creutzfeldt-Jakob disease in histopathology technicians. N 5. Sitwell L, Lach B, Atack E, Atack D, Izukawa D. Creutzfeldt-Jakob disease 6. Wakayama Y, Shibuya S, Kawase J, Sagawa F, Hashizume Y. High 7. Bruhn H, Weber T, Thorwirth V, Frahm J. In-vivo monitoring of neuronal 8. Collinge J, Palmer MS, Dryden AJ. Genetic predisposition to iatrogenic Other work presented suggested that BSE and bovine amyloidotic spongiform 3:30 Transmission of the Italian Atypical BSE (BASE) in Humanized Mouse Models Qingzhong Kong, Ph.D., Assistant Professor, Pathology, Case Western Reserve Bovine Amyloid Spongiform Encephalopathy (BASE) is an atypical BSE strain ***These results indicate that BASE is transmissible to humans and suggest that BASE is more virulent than There is a growing number of human CJD cases, and they were presented last He estimates that it may be up to 14 or 15 persons which display selectively http://www.fda.gov/ohrms/dockets/ac/06/transcripts/2006-4240t1.pdf Full Text Diagnosis and Reporting of Creutzfeldt-Jakob Disease Singeltary, Sr et al. JAMA.2001; 285: 733-734. BRITISH MEDICAL JOURNAL BMJ JOURNAL OF NEUROLOGY MARCH 26, 2003 disease in the United States comment on the CDC's attempts to monitor the occurrence of emerging forms of CJD. Asante, Collinge et al [1] have reported that BSE transmission to the 129-methionine genotype can lead to an alternate phenotype that is indistinguishable from type 2 PrPSc, the commonest sporadic CJD. However, CJD and all human TSEs are not reportable nationally. CJD and all human TSEs must be made reportable in every state and internationally. I hope that the CDC does not continue to expect us to still believe that the 85%+ of all CJD cases which are sporadic are all spontaneous, without route/source. We have many TSEs in the USA in both animal and man. CWD in deer/elk is spreading rapidly and CWD does transmit to mink, ferret, cattle, and squirrel monkey by intracerebral inoculation. With the known incubation periods in other TSEs, oral transmission studies of CWD may take much longer. Every victim/family of CJD/TSEs should be asked about route and source of this agent. To prolong this will only spread the agent and needlessly expose others. In light of the findings of Asante and Collinge et al, there should be drastic measures to safeguard the medical and surgical arena from sporadic CJDs and all human TSEs. I only ponder how many sporadic CJDs in the USA are type 2 PrPSc? TSS
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