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From: TSS ()
REPORT OF THE COMMITTEE ON SCRAPIE snip... Infected and Source Flocks As of September 30, 2006, there were 85 scrapie-infected and source flocks (48 infected and 37 source). There were a total of 116 new infected and source flocks reported for FY 2006. Figure 1 shows the number of new infected and source flocks by year. The total infected and source flock statuses that were released in FY 2006 was 100. A total of 343 positive scrapie cases were confirmed and reported by the National Veterinary Services Laboratories (NVSL). Of these, 70 were RSSS cases, (collected in FY 2006 and confirmed in FY 2006 or FY 2007), and 222 positive field necropsy cases (most of these cases were found during depopulations of scrapie exposed animals in infected/source flocks), 14 necropsies of field cases retained long term for test evaluation, and 37 third eyelid regulatory tests confirmed in FY 2006. Three of the field cases were goats. One goat case, in Colorado, could not be linked to exposure in sheep as a result Colorado goats no longer meet the requirements to be classified as low-risk goats or low-risk commercial goats for interstate movement. Approximately 3,822 animals were indemnified comprised of 62% non-registered sheep, 30% registered sheep, 5% non-registered goats and 3% registered goats. This represents a 26% decrease over FY 2005 with a significant shift from registered to grade animals. Regulatory Scrapie Slaughter Surveillance (RSSS) RSSS was designed based on 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 2006, collections increased by 9% overall and by 16% for black and mottled faced sheep compared to FY 2005. Improvement in the overall program effectiveness and efficiency is demonstrated by the 33% decrease in percent positive black faced sheep compared to FY 2005 (0.67 to 0.45%, based on test results posted before November 6, 2006). During FY 2006, 37,167 samples were collected. The distribution of these samples is shown in figure 2. There have been 70 NVSL confirmed positive cases that were collected in FY 2006. Face colors of these positives were 62 black and eight mottled. The percent positive by face color is shown in the figure 3 below. Scrapie Testing In FY 2006, 42,823 animals were sampled for scrapie testing: 37,167 RSSS; 3,649 regulatory field cases, 1,934 regulatory third eyelid biopsies, and 73 necropsy validations. Animal ID As of October 02, 2006, 118,668 sheep and goat premises have been assigned identification numbers in the Scrapie National Generic Database. Official eartags have been issued to 96,755 of these premises. Note: report based on data available as of November 6, 2006 snip... Descriptive Analysis and Scrapie Infected/Source Flocks and Investigations in FY 2006. Dianne Norden and Charles Gaiser Regional Epidemiologists Veterinary Services Infected and Source Flocks On average, Scrapie Infected/Source flocks identified in FY 2006 had an inventory of 98 animals (1,044), 23 animals indemnified on average (1-279), 3.45 positive animals found per flock upon flock cleanup plans. Of all these Infected/Source flocks for which data are available, 4,441 animals were involved in trace forward investigations. The primary breed of these flocks was predominantly blackfaced breeds, however there were 12 white-faced flocks identified (one Shetland, four Polypay Cross, four Southdown, three Dorset) and one flock whose primary breed was Dorper. Most of these flocks (89.7%) underwent a standard genetics based flock plan (flock genotyped and QQ animals removed). Other flock plans included variations on the standard genetics based flock plan (e.g. some high risk animals retained separately from the genetically less susceptible or resistant animals after lid testing “negative”, other flocks removed QRAV animals in addition to all QQs, and four flocks underwent a whole flock depopulation. These flocks were primarily identified because of a positive found at slaughter (43%). Other detection methods included trace forward of exposed animals (30%), trace back to birth flock of positive animals (19%), investigation of clinical suspects (7%) and voluntary surveillance (1%). Investigations Attempts were made to trace 4,889 high risk sheep out of these Infected and Source flocks. While some of these investigations are still ongoing (9%), 16% were untraceable and 75% were traceable to a flock. Almost 30 (27) clinically suspicious sheep were investigated in FY 06. Seven of these animals were ultimately diagnosed with scrapie resulting in five newly discovered Infected or Source flocks. Nearly 37,000 (36,891) samples were collected at slaughter. Of these, 55 positive animals were detected, and 31 were successfully traced back to their flock of origin, resulting in 27 newly discovered Infected or Source Flocks. Over 20 (22) traces are still ongoing, and two of these positives were untraceable. Scrapie positive animals Of the Scrapie positive animals that were found, 75% (116) were female, and most (90%) had lambed or aborted in their flock of origin. Most (65%) were still in their flock of birth at the time of diagnosis. Nearly all (99.2%) of all positive animals found were QQ, of those that were QQ, most (89.2% were QQAA). One animal has initially tested QRAA; the genotype of this animal is being confirmed. One QRAV positive was detected in FY 2006. Most positive animals were found as part of an Infected or Source flock depopulation (45%). Other methods of detection included RSSS traceback (28%), traceforward investigations (20%), investigation of clinical suspects (5%), and Voluntary Surveillance (2%). The breeds of these positives was predominantly black-faced breeds (99), but there were 63 White-faced breeds identified (40 Southdown, 11 Polypay Cross, two Dorsets, and 10 nonspecified white-faced or white-faced crosses). The average age of scrapie-positive animals was 3.9 years, ranging from six months to 12 years of age. http://www.usaha.org/committees/reports/2006/report-scr-2006.pdf 12/10/76 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 1: 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 Models Qingzhong Kong, Ph.D., Assistant Professor, Pathology, Case Western Reserve Bovine Amyloid Spongiform Encephalopathy (BASE) is an atypical BSE strain 6:30 Close of Day One 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 disease in the United States I lost my mother to hvCJD (Heidenhain Variant CJD). I would like to 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? Singeltary, Sr et al. JAMA.2001; 285: 733-734. http://jama.ama-assn.org/
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