#IDFridays Week 48: West Nile Virus

Name
West Nile Virus aka WNV (name comes from the West Nile district of Uganda where it was discovered in 1937)

Transmission

A virus that lives in birds but can spread to and infect humans, horses, and other mammals
- When mosquitoes bite birds infected with WNV, the virus enters the mosquitoes and when those infected mosquitoes bite humans and other mammals, the virus spreads
West Nile virus is mainly transmitted to people through the bites of infected mosquitoes
- Though rare, human infections have also occurred through organ transplant, blood transfusions, and breast milk from an infected person

Geography
Africa, Europe, the Middle East, North America and West Asia

Incubation Period
2 – 14 days

Signs and Symptoms

80% of infected people do not show any symptoms but common symptoms include:

Approximately 1 in 150 people develop a more severe form of disease with the following symptoms:

Diagnosis
Laboratory testing of blood and spinal fluid samples

Treatment

There is no vaccine or specific treatment for WNV
Those with the more severe form of the disease receive supportive treatment for the symptoms which can include intravenous fluids, pain medications, respiratory support, and prevention of secondary infections

Prognosis

People with mild symptoms typically recover on their own, although some symptoms may last for several weeks
The severe form of WNV can lead to death for 10% of the patients that develop it
- This severe form begins with brain swelling and meningitis
- Recovery from the severe disease may take several weeks or months
- For those that survive, some of the neurological symptoms may never go away

Prevention: What Can You Do?

Avoid mosquito bites:

West Nile Virus In the News