I)letccl. The Plum Island Laboratory of the 

 Animal Disease and Parasite Research Divi- 

 sion is also available for assistance in diag- 

 nosis. Statutory prohibition exists against the 

 importation of foreign animal disease produc- 

 ing agents to any point in this country except 

 Plum Island. For this reason many of the 

 tests for such diseases can be conducted only 

 at that laboratory. 



Vesicular diseases 



During 1960, 64 reports of suspected vesicu- 

 lar conditions were received in Washington. 

 Each of these cases was investigated and serum 

 or tissue specimens were submitted for labo- 

 ratory tests. A positive diagnosis of New Jer- 

 sey type vesicular stomatitis was made in 21 

 of the 64 cases. In each case in which the diag- 

 nosis was negative, the herd or animal involved 

 was regularly reinspected until it could be sat- 

 isfactorily determined that the condition was 

 not vesicular. Each tissue specimen received 

 was checked by complement fixation test 

 again.st the .seven known types of FMD anti- 

 sera, with negative results. 



Foot-and-mouth disease 



With the exception of North America, Cen- 

 tral America, Australia, and New Zealand, 

 foot-and-mouth disease is considered to be en- 

 zootic in the major livestock countries of the 

 world. The disease has been known for more 

 than 100 years. It was not until the latter part 

 of the 19th century, however, that its economic 

 importance was fully realized. 



There have been nine outbreaks of foot-and- 

 mouth disease in the United States. Not the 

 last, but perhaps the worst, struck in 1914. It 

 started in Berrien County, Mich., in August 

 of that year. For reasons explainable only by 

 lack of alert and trained diagnosticians and an 

 inadequate emergency disea.se reporting sys- 

 tem, the disease went undiagnosed until Octo- 

 ber 15. 



The Union Stockyards in Chicago were quar- 

 antined on October 28, and the machinery of 

 eradication finally moved into gear. But be- 

 fore the emergency ended, on June 5, 1916, 

 havoc and death had spread to the livestock 

 industry of 22 States. Nine million dollars 



had been spent; 172,222 cattle, sheep, swine, 

 and goats had been sacrificed. 



Vesicular stomatitis 



The dust from the foot-and-mouth disease 

 campaign had hardly settled when "the event 

 of greatest consequence" in 1917 unfolded. 



From the concentration remount station near 

 Chicago, came word of a disease of the mouths 

 and tongues of horses. The disease was traced 

 to similar remount stations at Grand Island, 

 Nebr., and Denver, Colo., where thousands of 

 horses and mules had been gathered for ship- 

 ment to the armies of France and Britain. 



Sick animals were immediately isolated, 

 quarantined, and treated. Infected pens were 

 cleaned and disinfected. 



Then, a carload of horses from Nebraska 

 arrived at Denver. Several animals were re- 

 jected and returned. Four days later the re- 

 jected animals had developed lesions that 

 quickly spread to horses and cattle on neighbor- 

 ing ranches. And before anyone was fully 

 aware of what was happening, inspectors at 

 Kansas City were reporting lesions resembling 

 foot-and-mouth disease in cattle shipped from 

 Nebraska. 



The lesions were diagnosed as those of vesic- 

 ular stomatitis (VS), a disease well known in 

 Europe and South Africa, but up to that time 

 only occasionally noted in the United States. 

 Before it was controlled, VS had spread from 

 Nebraska and Colorado to ranches and remount 

 .stations in South Dakota and Wyoming, and 

 through the usual trade channels to the At- 

 lantic Coast and to France. 



In 1917, a prompt and exact differentiation 

 in cattle between foot-and-mouth disease and 

 vesicular stomatitis was accompanied by many 

 difficulties. Not least among them was the 

 awareness that a mistaken pronouncement 

 could lead, on the one hand, to unnecessary and 

 serious economic disturbances and, on the 

 other, to the spread of one of the most dread 

 and readily communicated animal plagues. 



Vesicular stomatitis is endemic in certain 

 parts of the United States and Mexico. It has 

 occurred sporadically in some parts of Central 

 and South America. In this country, the dis- 

 ease seldom occurs in winter. It appears an- 

 nually during the warmer months in the coastal 



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