What are the symptoms of West Nile Virus?

Not all humans infected with the West Nile virus become ill. Most infections are mild. Symptoms may develop within three to fifteen (3 - 15) days. When symptoms develop, they may include fever, headache, stiff neck, muscle weakness and mental confusion. In rare cases, more severe infections may result in high fever, tremors, disorientation and other signs of increasing illness. Symptoms should be evaluated by your healthcare provider.