Passionate about Healthcare? Join our team and help us shape a healthier tomorrow!

Health Library

West Nile Virus

West Nile Virus

Summary

West Nile virus (WNV) is an infectious disease that first appeared in the United States in 1999. Infected mosquitoes spread the virus that causes it. People who get WNV usually have no symptoms or mild symptoms. The symptoms include a fever, headache, body aches, skin rash, and swollen lymph glands. They can last a few days to several weeks, and usually go away on their own.

If West Nile virus enters the brain, however, it can be life-threatening. It may cause inflammation of the brain, called encephalitis, or inflammation of the tissue that surrounds the brain and spinal cord, called meningitis. A physical exam, medical history, and laboratory tests can diagnose it.

Older people and those with weakened immune systems are most at risk. There are no specific vaccines or treatments for human WNV disease. The best way to avoid WNV is to prevent mosquito bites:

  • Use insect repellent
  • Get rid of mosquito breeding sites by emptying standing water from flower pots, buckets or barrels
  • Stay indoors between dusk and dawn, when mosquitoes are most active
  • Use screens on windows to keep mosquitoes out

National Institute of Allergy and Infectious Diseases

Find an Expert

Start Here

Related Issues

Prevention and Risk Factors

Journal Articles

Statistics and Research

Patient Handouts

Symptoms