West Nile Virus: Use Protection. Avoid Infection

West Nile Virus (WNV) is the leading cause of mosquito-borne disease in the United States. WNV is usually spread by the bite of an infected mosquito. Mosquitoes carry the virus after they become infected from feeding on infected birds. Infected mosquitoes can spread WNV to humans and other animals that they bite. Cases of WNV occur during mosquito season, which starts in the summer and continues through the fall. WNV has no vaccine to prevent infection.

Fortunately, most people infected with WNV (eight out of 10) do not feel sick. About one in five people who are infected develop a fever with other symptoms such as headache, body aches, joint pains, vomiting, diarrhea, or rash. Most people with febrile illness due to West Nile virus recover completely, but fatigue and weakness can last for weeks or months. About one out of 150 people who are infected develop serious symptoms affecting the brain and central nervous system. Treatment for WNV is limited to supportive care only.

See your healthcare provider if you develop the symptoms described above. Your healthcare provider can order tests to look for West Nile virus infection.

You can reduce your risk of WNV by using insect repellent and wearing long-sleeved shirts and long pants to prevent mosquito bites. Use Environmental Protection Agency (EPA)-registered insect repellents with one of the active ingredients below. When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breastfeeding women.

DEET

Picaridin

Use screens on door and windows and repair holes in screens to keep mosquitos outdoors. Use air conditioning, if available. Stop mosquitoes from laying eggs in or near water. Once a week drain standing water around your house.

For more information see: dphhs.mt.gov/publichealth/cdepi/diseases/westnilevirus.