West Nile virus (Flavivirus) was first discovered in Africa and was accidentally introduced to the United States, according to the USDA. The virus is primarily an avian pathogen, transmitted among ... more 
West Nile virus (Flavivirus) was first discovered in Africa and was accidentally introduced to the United States, according to the USDA. The virus is primarily an avian pathogen, transmitted among birds by bird-biting mosquitoes, such as the As less 
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Wed, Aug 29, 2012 9:00 AM EDT