Most people who are infected have no symptoms or may experience mild illness such as a fever or a headache before fully recovering. In some individuals, particularly the elderly, West Nile Virus can cause serious disease that affects the central nervous system. Symptoms generally occur 5 to 15 days after the bite of an infected mosquito. They range from slight fever, headache, rash, swollen nodes and conjunctivitis to rapid onset of a severe headache, high fever, stiff neck, disorientation, muscle weakness, coma or death. Most mosquitoes are NOT infected with the West Nile Virus.
Illnesses related to mosquitoes are rare.
However, you should see your doctor immediately if you develop symptoms such as high fever, confusion, muscle weakness, or severe headaches. Patients with mild symptoms are likely to recover completely, and do not require any specific medication or laboratory testing.