West Nile virus can cause serious, life-altering, and even fatal disease in humans. Precautions should be taken to avoid being bitten by mosquitoes particularly during the peak transmission periods of late August and early September. Humans can also be infected when conducting necropsies on infected birds. Most humans infected with the virus develop inapparent infections. Clinically-ill people develop either West Nile Fever or the more severe WNV encephalitis. Clinical symptoms of West Nile Fever are usually mild and include fever, headache, body aches, and in some cases, skin rash and swollen lymph nodes. Clinical signs of WNV encephalitis include high fever, stiff neck, muscle weakness, convulsions, and paralysis. Death rates associated with severe WNV infection range from 3–15% and are highest among the elderly.