West Nile Virus
Also known as: WNV.
What is West Nile virus?
West Nile virus is a disease that was only recently discovered in the United States. It usually causes mild symptoms but can cause severe problems if it affects the brain. It is transmitted by infected mosquitoes.
What causes West Nile virus?
A mosquito infected with the West Nile virus most often causes the disease. It does not appear to be spread from person to person. Serious complications of West Nile virus tend to occur in older people or individuals with other diseases like cancer or diabetes.
What are the symptoms of West Nile virus?
Typical symptoms of West Nile virus include fever, diarrhea, vomiting body aches, fatigue and rash. Serious infections can cause high fever, headache, stiff neck, tremors, seizures, confusion, coma and paralysis.
What are West Nile virus care options?
There is no cure for West Nile virus. Some people only require over-the-counter medication for symptoms, while serious cases often require hospitalization and supportive measures to prevent or help with severe complications.
Reviewed by: Carolina Sanchez-Vegas, MD
This page was last updated on: September 16, 2025 12:28 PM
Infectious Diseases
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