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From: TSS ()
June 17, 2005, 6:06AM Federal regulators skipped a key test last November that is routinely used elsewhere by experts who say it is, under certain circumstances, more effective for detecting the dread disease. Relying on a single kind of test to verify the results of an initial screening, USDA officials declared the cow — reportedly from Texas — free of the disease. That was a decision they have come to rue. Seven months later, they had to acknowledge the animal may have been infected after all. That troubling reversal sent cattle prices falling this week and sparked new questions about the USDA's ability to protect the public while at the same time trying to promote U.S. agricultural interests. "They don't go the extra mile," argued Craig Culp, a spokesman for the Center for Food Safety in Washington. "They stop just short of it, cross their fingers and hope everything is OK." Scrambling to salvage the department's reputation, USDA officials Thursday ordered a battery of new tests on the suspect animal. And Jim Rogers, a spokesman for USDA's Animal and Plant Health Inspection Service, said the agency is reviewing its approach to mad cow cases. That news comes none too soon for U.S. beef producers, who have been struggling to re-open foreign markets closed to them after the first mad-cow scare. The "fogginess" created by the USDA's handling of this case "messes with the credibility of our strict standards." said Shane Sklar, executive director of the Independent Cattlemen's Association of Texas. When USDA officials encountered their first suspected case of bovine spongiform encephalopathy — better known as mad cow disease — in late 2003 in a cow from Washington state, the agency used what's known as the immunohistochemistry or IHC test to confirm the animal had the disease. After the IHC test came up positive, regulators then went further and conducted what's known as a Western blot analysis, a procedure used widely in Europe and Japan. They also asked a lab in Weybridge, England, considered the world's foremost testing facility for the disease, to verify the results. The cow was found to be infected, and more than 50 countries closed their borders to U.S. beef exports. In response, the USDA launched a program in June 2004 to screen more widely for the disease, using a procedure known as a "rapid test." More than 381,000 head of cattle have been tested since that time. Rapid tests from three animals produced potentially troubling results. USDA officials checked those initial results by using the IHC test, what they have called the "gold standard." A cow singled out by the initial test as the most likely to be infected was tested twice. The IHC tests were negative on all three animals. Last November, officials announced the most suspicious-looking cow was free of the disease. USDA officials did not employ the Western blot test to further verify the IHC results, contending the two tests are "equally effective." Rogers noted that since a Western blot test had confirmed the results of an IHC analysis on the Washington cow, agency officials believed they had all the necessary protocols in place. Many experts say both tests are needed. At Weybridge, officials use the IHC test but employ others as well, including variations of the Western blot method. Aguzzi's institution, however, routinely runs a Western blot test enhanced with another step "on every suspect case, because of its unrivalled specificity and because — in most cases — we find it to be much more sensitive than immunohistochemistry." In the months since the November announcement, the USDA came under intense pressure from organizations such as Consumers Union for failing to conduct a Western blot test on the suspect cow. Activists at Consumers Union pointed to reports in veterinary literature which suggested IHC could miss some cases. Michael Hansen, a senior research associate with Consumers Union, says he confronted USDA officials about the issue during the June 6 meeting of Institute of Medicine of the National Academies. Then, that same week, the Agriculture Department's inspector general, who has been monitoring the department's performance in screening for mad cow disease, ordered USDA officials to retest samples from all three cows that had produced questionable results last year using the Western blot method. What prompted that action by Inspector General Phyllis Fong's office is not entirely clear. The retesting was done quietly. As late as June 9, Agriculture Secretary Mike Johanns was referring to "that single cow" in Washington state that had been found stricken with the disease. Late Friday evening, USDA officials announced that a Western blot test conducted on the cow declared clear of the disease last November was showing what was described as a "weak positive." Hansen scoffs at that designation: "You don't say someone is a little bit pregnant." Thursday evening, USDA officials announced that the Weybridge laboratory will perform its own IHC tests, as well as three variations of the Western blot, while USDA officials will conduct their own tests. And they're reviewing how they will handle future cases. david.ivanovich@chron.com http://www.chron.com/cs/CDA/ssistory.mpl/front/3229428 -------- Original Message -------- Greetings list members, I was going over the data from the 1st documented BSE/TSE cow On December 23, 2003, a Canadian cow shipped to slaughter from a farm in So APHIS put in a high-priority call to veterinary medical officer "We had experience with the Western blot test and we had all the full text; http://www.ars.usda.gov/is/AR/archive/dec04/tse1204.htm TSS Terry S. Singeltary Sr. wrote: > ##################### Bovine Spongiform Encephalopathy snip...end full text ; http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf It was, however, performed in the USA in 1979, when it was shown that cattle inoculated with the scrapie agent endemic in the flock of Suffolk sheep at the United States Department of Agriculture in Mission, Texas, developed a TSE quite unlike BSE. 32 The findings of the initial transmission, though not of the clinical or neurohistological examination, were communicated in October 1988 to Dr Watson, Director of the CVL, following a visit by Dr Wrathall, one of the project leaders in the Pathology Department of the CVL, to the United States Department of Agriculture. 33 The results were not published at this point, since the attempted transmission to mice from the experimental cow brain had been inconclusive. The results of the clinical and histological differences between scrapie-affected sheep and cattle were published in 1995. Similar studies in which cattle were inoculated intracerebrally with scrapie inocula derived from a number of scrapie-affected sheep of different breeds and from different States, were carried out at the US National Animal Disease Centre. 34 The results, published in 1994, showed that this source of scrapie agent, though pathogenic for cattle, did not produce the same clinical signs of brain lesions characteristic of BSE. http://www.bseinquiry.gov.uk/report/volume2/chaptea3.htm Visit to USA ... info on BSE and Scrapie http://www.bseinquiry.gov.uk/files/yb/1988/10/00001001.pdf WHY is USA insisting _now_ not to use WB, when on the 1st _confirmed_ case Dec. 23, 2003 maybe this is the reason ; JAPAN BSE # 8 & 9 cow 8. 6/10/2003 Holstein Steer 13/10/2001 23 mths =========== More information on the first 11 Japanese BSE-cases can be found on the website of the Japanese Embassy in the US: http://www.us.emb-japan.go.jp/english/html/fafacts/bse/bse.htm it's gonna be a long year........ TSS ######### https://listserv.kaliv.uni-karlsruhe.de/warc/bse-l.html ########## This is an automatic response to your e-mail. Letters to Viewpoints Thank you for your letter to Viewpoints. To be considered for TSS
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