Only about 20 percent of infected people suffer any ill effects at all. Ordinary West Nile fever produces aches and pains, nausea and vomiting, and other flu-like symptoms that typically disappear after only a few days. However, about 1 person in 150 will become seriously ill and may develop a brain infection called encephalitis. The virus can also affect the tissues around the brain, where it causes a form of meningitis,
Only about 20 percent of infected people suffer any ill effects at all. Ordinary West Nile fever produces aches and pains, nausea and vomiting, and other flu-like symptoms that typically disappear after only a few days. However, about 1 person in 150 will become seriously ill and may develop a brain infection called encephalitis. The virus can also affect the tissues around the brain, where it causes a form of meningitis,