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The Naturalist: |
Avian Flu |
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The Naturalist: |
Avian Flu |
Updated 3/21/06
There is no recognized public health risk associated with wild bird contact due to the bird flu virus in the United States. No wild waterfowl species hunted in North America has been found to be infected with "bird flu". In addition, there is no documented case of avian influenza virus transmission directly from wild birds to humans so you don't need to fear getting "bird flu" from feeding birds in your back yard or when hunting. (Of course, one always practices careful hygiene when handling wild birds or mammals. Wear gloves when handling wild animals or carcasses and wash your hands well after filling bird feeders and cleaning bird baths.) These assurances come from a report released by the College of Veterinary Medicine, University of Georgia and updated on November 4, 2005.
Avian influenza viruses (AIV) are Type A influenza viruses associated with avian species varying in their pathogenicity and isolated from more than 100 species of free-living birds world-wide. HPAI viruses are avian influenza viruses that are that cause high mortality in domestic poultry.
"Bird flu" is a nonscientific term that was coined to describe the particular HPAI virus, HPAI H5N1, which caused a human death in 1997. Since then, almost all human cases have been linked to direct contact with infected poultry.
In 2002/2003, wild bird mortality in Hong Kong was attributed to infection with this virus . As wild bird mortality associated with the "bird flu" virus has continued through 2005, its current distribution suggests movement of this virus via migratory birds, particularly ducks, geese, swans, gulls, terns, and shorebirds. It is worth repeating: no wild waterfowl species hunted in North America has yet been found to be infected with bird flu.
Although migratory bird species move between North America, Asia, and Europe, genetic studies of avian influenza viruses from Eurasia and North America suggest that there is very limited exchange of AIV viruses between continents, even with very common avian influenza viruses. Although introduction of bird flu through migratory birds to North America is possible, it is appears to be unlikely according to the known epidemiology of other avian influenza viruses.
For more information, see the following websites: