SCRAPIE 



Scrapie in history 



Scrapie has been known in Great Britain 

 and Western Europe for more than 200 years. 

 There is evidence that Spanish Merino sheep 

 may have carried the disease into Europe. The 

 disease has been reported in Australia. Austria, 

 Canada, England, France, Germany, Hungary, 

 Iceland (where a similar disease is called 

 Rida), New Zealand, Norway, Poland, Scot- 

 land, Spain, and Wales. 



The first report in the United States was 

 from Michigan in 1947. Scrapie was again re- 

 l)orted in October 1952 when, in two related 

 California outbreaks, 21 sheep showed symp- 

 toms. The United States Livestock Sanitary 

 Association and segments of the sheep industry 

 urged immediate eradication action. And on 

 October 31, 1952, with an emergency declara- 

 tion by the Secretary of Agriculture, the coop- 

 erative Scrapie eradication program was es- 

 tablished. 



All sheep in the two California flocks and all 

 exposed sheep moved from them were slaugh- 

 tered, as were the immediate progeny. The 55 

 premises involved were cleaned and disin- 

 fected. More than 7 years have passed with 

 no extension of infection fi'om these outbreaks. 

 California has since suffered six additional out- 

 breaks that were not associated with those in 

 1952. The source of the earlier outbreaks is 

 believed to have been a Canadian flock. 



Sheep rubbing against fence rail — an early symptom, 

 from which the disease derives its name. 



The di-sease .struck next in Ohio where, in 

 1953, five infected flocks were found. The 

 eradication program in Ohio included slaughter 

 of infected flocks but not exposed sheep moved 

 from them or the immediate progeny of the ex- 

 po.sed sheep. Certain of the.se animals in Ohio 

 and Tennessee were later found to have 

 scrapie. During the same year, scrapie was 

 diagno.sed in three Illinois flocks. These flocks 

 and exposed sheep moved from them were 

 slaughtered. 



In both Ohio and Illinois it appeared that the 

 disease had been introduced from the Canadian 

 flock involved in the first California outbreaks. 



Indiana has had 23 infected ttock.s — more 

 than any other State. The earliest case was 

 in August 1954, and the most recent in April 

 1959. Eight of these flocks, as well as two in 

 Alabama, two in North Carolina, and one in 

 Missouri, acquired the disease through move- 

 ments of exposed sheep from one of the Indiana 

 flocks. These 13 outbreaks in 4 States resulted 

 from the movements of 322 exposed sheep into 

 85 flocks in 14 States — a classic example of 

 spread. Had the remaining expo.sed .sheep not 

 been slaughtered, additional cases would un- 

 doubtedly have developed. 



It became obvious that scrapie could not be 

 eradicated unless both source and infected 

 flocks were slaughtered ; and that exposed 

 sheep from those flocks and their immediate 

 progeny should be slaughtered also. Source 

 flocks were defined as those determined on am- 

 ple evidence, and after careful consideration 

 and consultation, to be disseminating scrapie; 

 but in which no animals were found that 

 showed symptoms of the disease. 



In the United States, 91 infected flocks have 

 been reported in the following 24 States: Ala- 

 bama 2, California 8, Connecticut 2, Georgia 

 1, Illinois 15, Indiana 23, Iowa 1, Kentucky 1, 

 Maryland 2, Michigan 2, Mississippi 1, Mis- 

 souri 1, New York 3, North Carolina 2, Ohio 

 12, Oregon 4, Tennessee 2, Texas 1, Utah 1, 

 Virginia 1, West Virginia 1, Wisconsin 2, and 

 Wyoming 2. 



There were 10 outbreaks in 1953; 3 in 1954; 

 11 in 1955; 23 in 1956; 12 in 1957; 7 in 1958; 

 1 1 in 1959 ; and 13 in 1960. 



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