West Nile Virus

West Nile virus (WNV) is also transmitted to humans and some animals through the bite of an infected mosquito.

The incubation period for WNV—the amount of time from infection to symptom onset—is typically from between 2 and 15 days. Headache can be a prominent symptom of WNV fever, meningitis, encephalitis, meningoencephalitis, and it may or may not be present in poliomyelitis-like syndrome. Thus, headache is not a useful indicator of neuroinvasive disease.

About 20 percent of people develop a mild infection called West Nile fever. Common signs and symptoms of West Nile fever include:

Fever
Headache
Body aches
Fatigue
Back pain
Skin rash (occasionally)
Swollen lymph glands (occasionally)
Eye pain (occasionally)

No specific treatment is available for WNV infection. In severe cases treatment consists of supportive care that often involves hospitalization, intravenous fluids, respiratory support, and prevention of secondary infections.