PN-3660 



A scientist studies the results of foot-and-mouth disease virus on a ratio recording instrument. 



affect their susceptibility. These studies are 

 being done to obtain highly susceptible cultures 

 for diagnosis of viral diseases and for other work 

 involving assay or production of viruses. 



Microbiological 



Scientists in microbiological investigations 

 study the susceptibility of various species of 

 animals to virus diseases, explore ways in which 

 the diseases spread, and determine in what 

 organs and tissues the virus may be found. They 

 study the factors that result in animals becoming 

 virus carriers. They also trace the survival of 

 viruses in meat, blood, semen, and other animal 

 products. From the results of these studies, the 

 U.S. Department of Agriculture is able to assess 

 the hazards of importing live animals and animal 



materials from foreign countries in which 

 dangerous diseases exist. 



Scientists also study the effects of chemical 

 and physical environments on viruses and thus 

 contribute to knowledge regarding methods of 

 virus inactivation, disinfection of contaminated 

 materials and premises, and survival of viruses 

 under various conditions. Such information is 

 vital in preventing disease and eradicating out- 

 breaks. 



Diagnostic 



When USDA veterinary diagnosticians in the 

 field observe animals showing clinical signs 

 suspicious of foreign animal disease, they collect 

 samples and submit them to Plum Island. At 



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