Raccoon Rabies — In Ohio, New York, and 

 Vermont, WS assisted in the distribution of 

 almost 1.8 million oral raccoon rabies vaccine 

 baits in FY 1999, distributed over more than 

 4,500 square miles. This program was 

 designed to stop the westward spread of the 

 raccoon strain of rabies by creating buffer 

 zones where the rabies virus will die out. 

 Cooperative monitoring and surveillance has 

 shown good uptake of the vaccine baits by 

 raccoons, resulting in a substantial reduction 

 in the number of rabies-positive raccoons in 

 the treated areas. 



West Nile Virus— West Nile virus (WNV)— 

 a virus with enormous potential to damage 

 human health, livestock, and wildlife— was 

 first documented in the United States in the 

 late summer of 1999. The disease spread 

 quickly and was responsible for the deaths of 

 7 of 61 people diagnosed with WNV-caused 

 encephalitis and 9 of 23 horses in the New 

 York City area. The virus also infected a 

 variety of captive birds at the Bronx Zoo and 

 thousands of wild crows along the east coast. 

 Birds serve as the natural host for the virus, 

 which is transmitted to humans and other 

 animals through the bite of mosquitoes. 



In response, WS prepared for a collaborative 

 effort in FY 2000 to conduct surveillance for 

 WNV in wild bird populations along the 

 Atlantic coast to determine which species were 

 infected and if the virus could be carried to 

 other States through southerly fall migrations. 

 This information assists local health and 

 agriculture agencies in preparing for and 

 responding to WNV outbreaks. Other 

 participating agencies were the U.S. Geologi- 

 cal Survey's National Wildlife Health Center 

 and the U.S. Department of Health and Human 

 Services' CDC. Blood samples collected by 

 WS from crows, house sparrows, and feral 

 pigeons in New York, Pennsylvania, Connecti- 

 cut, Delaware, New Jersey, Maryland, Virginia, 

 North Carolina, South Carolina, Georgia, and 



Florida will be provided to the National 

 Wildlife Health Center and some State health 

 laboratories for testing. WS will collect 

 samples and collaborate with cooperating 

 Federal, State, and local agencies through FY 

 2000. 



Other disease surveillance work conducted by 

 WS in FY 1999 included the collection of 

 blood samples from predators for bubonic 

 plague titer monitoring by health departments 

 in Nevada, Texas, California, and Colorado 

 and hantavirus monitoring in several Western 

 States. 



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