What are the symptoms of West Nile Virus?

West Nile Virus (WNV) can affect the central nervous system. The severity of symptoms can vary from person to person.

  • No symptom in most people: Approximately 80 percent of people who are infected with WNV will not show any symptoms and will not know they have it.
  • Mild infection in some people: Up to 20 percent of the people who become infected will display mild flu-like symptoms, including headache and body aches, nausea, vomiting, as well as swollen lymph glands, or a skin rash on the chest, stomach, and back. Symptoms typically last a few days. This is known as West Nile Fever.
  • Serious infection in a few people: About one in 150 people infected with WNV will develop severe illness, such as West Nile Encephalitis, West Nile Meningitis, or West Nile Meningoencephalitis. The symptoms can include headache as well as neck stiffness, confusion, and high fever. These symptoms may last several weeks or even months. The neurological effects may be permanent.
  • WNV is known to cause death in rare circumstances.

Show All Answers

1. What is the West Nile Virus?
2. How does the West Nile Virus spread?
3. Is the West Nile Virus contagious?
4. How soon do you get the symptoms once you have been bitten?
5. What are the symptoms of West Nile Virus?
6. How is West Nile Virus treated?
7. Does the Health Department offer free testing?
8. Can I get the virus twice?
9. My child or I was bitten by a mosquito, what should I do?
10. What should I do if I think I have WNV?
11. What is Dallas County doing?
12. What can I do?
13. What should I do if I see dead birds in my yard?
14. Can dogs, cats, and other pets get West Nile Virus?
15. Are pesticides harmful to people?
16. Where can I learn more information?