What is the prognosis for West Nile virus infection?

Most people (70%–80%) infected with West Nile virus (WNV) do not develop any symptoms. Up to 20% of infected people will develop West Nile fever (WNF), which may manifest with fever, headache, body aches, joint pains, vomiting, diarrhea, or a rash. About 1% of people infected with WNV will develop severe neuroinvasive disease, such as encephalitis (inflammation of the brain) or meningitis (inflammation of the lining of the brain and spinal cord). These severe infections can cause death or permanent neurological damage.

The prognosis for WNV infection depends on the severity of the disease. For people with WNF, the symptoms usually resolve within a few days or weeks. For people with severe neuroinvasive disease, the prognosis is more variable and depends on the individual's age, underlying health conditions, and the severity of the infection. Some people may recover fully, while others may experience permanent neurological damage or death.

There is no specific treatment for WNV infection. Treatment is supportive and may include rest, fluids, pain relievers, and hospitalization for severe cases. There is a vaccine available to prevent WNV infection, and it is recommended for people who are at high risk of infection, such as those over the age of 60, those with weakened immune systems, and those who live in areas where WNV is common.