o Antibiotics or other specific medications are not effective against this infection, and no 
     
     vaccines against this virus are approved for use in people or animals. 
     
    
   
   
    
     In mid August, 1999 wild crows were found dead at the Bronx Zoo in New Your City. About the 
     
     same time, there were reports of encephalitis, originally thought to be due to St. Louis Encephalitis, a 
     
     related arbovirus, in people in New Your City. By late August, dead crows were reported in many parts of 
     
     downstate New York and Long Island. Deaths in captive birds began in the Bronx Zoo in early September 
     
     and continued over a three-week period. Unusual mortalities of wild birds occurred into early November 
     
     on Long Island, downstate New York, and adjacent New Jersey and Comiecticut within an approximately 
     
     200 km radius of New York City. Horses with encephalitis began to die on Long Island in late August, 
     
     and continued into October. West Nile Virus was isolated from affected crows and other wild birds, 200 
     
     birds, people, horses and mosquitoes. 
     
    

    
     West Nile Virus may have been introduced to the New York area by migratory birds, legal or 
     
     illegal imports of birds, in a person incubating the virus, or by the transport of infected mosquitoes via 
     
     aircraft. 
     
    

    
     The 1999 New York area outbreak caused disease in at least 60 people and resulted in 7 human deaths, 
     
     including one Canadian from Toronto who had visited New York. It likely killed at least 5,000 wild birds, 
     
    

    
     ' mainly American crows, but it also affected at least 17 other species of native wild (Blue Jay, Fish Crow, 
     
     Ring-billed Gull, Herring Gull, Yellow-billed Cuckoo, Rock Dove, American Robin, Red-tailed Hawk, 
     
     Broad-winged Hawk, Cooper’s Hawk, American Kestrel, Belted Kingfisher) and captive (Bald Eagle, 
     
     Laughing Gull, Sandhill Crane, Black-crowned Night Heron, Mallard) birds, as well as Chilean Flamingos 
     
     and unspecified pheasants and cormorants. Twenty-four horses Were affected and at least 10 died or had 
     
     to be killed humanely. 
     
    

    
     American health officials responded to the West Nile Virus outbreak with public education 
     
     campaigns emphasizing reduction of mosquito habitat, mosquito avoidance and use of repellants, 
     
     surveillance of mosquitoes, birds, people and horses for West Nile Virus infection; and mosquito control 
     
     programs. 
     
    

    
     Canadian federal and provincial animal health and public health agencies are concerned that West 
     
     Nile Virus may be brought to Canada this spring by migrating birds, since infected or incubating birds 
     
     may remain asymptomatic. The situation is unprecedented, and it is impossible to evaluate accurately the 
     
     probability of virus introduction. Canadian epidemiologists are monitoring the situation in the United 
     
     States, where any West Nile Virus activity is expected to occur first. Surveillance for unusual mortalities 
     
    

    
     ‘ in wild birds is an important part of the Canadian West Nile Virus response, which, in addition, may 
     
     involve surveys for West Nile Virus infection in wild and domestic birds, and in mosquitoes, as well as in 
     
     domestic animals, as the situation demands. The goal is to reduce the risk of human infection through 
     
     public education and mosquito abatement if, where, and when the situation warrants such action. 
     
    

    
     If West Nile Virus becomes active in 2000, you can reduce your 
     
     risk of exposure by becoming informed of localities where it is 
     
     circulating. If possible, avoid such areas or minimize outdoor activities 
     
     where mosquitoes are likely to be encountered, especially at dawn, at 
     
     dusk and at night. Adopt personal protective measures, such as use of 
     
     repellants, nets, etc., if exposure to mosquitoes cannot be avoided. 
     
    

    
     In addition, keep an eye out for warning signs that our wild birds, especially American Crows, may 
     
     provide. Unusual outbreaks of bird mortality should be reported to Dr. Pierre-Yves Daoust ([902] 566- 
     
     0667) or Dr. Scott McBurney ([902] 566-0959), CCWHC-Atlantic Region, at the Atlantic Veterinary 
     
     College, Charlottetown, PEI, especially if neurologic disease is suspected. Dead birds can safely be 
     
    

    
     picked up using rubber gloves or a leak proof plastic bag turned inside out. The plastic bag containing the 
     
    
   
   
    
       
     
    
   
   
    
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