The first West Nile virus detection of the season was found in mosquitoes collected in Yakima County this week by Benton County Mosquito Control District. It’s the first sign that the virus is active in our state this summer. The warmer spring and early summer weather is ideal for high mosquito numbers. Preventing mosquito bites is the most effective way to avoid West Nile virus disease.

Department of Health and local partners have already started their yearly trapping and testing of mosquitoes that can carry the virus. Each year since 2005, West Nile virus has been detected in mosquitoes, birds, or animals in south-central Washington, and occasionally in other areas of the state. Over the winter, two dead birds collected for bird flu testing in Benton County tested positive for West Nile virus. Dead birds can be the first sign that the virus is in an area and we encourage people to report dead birds online. West Nile virus activity in Washington varies from year to year so it’s not known how many people may become sick with the virus this year.

The pattern of West Nile virus in our state shows there are some areas in south-central Washington where mosquitoes carrying the virus thrive, say state health officials. Areas with a combination of warm weather, irrigation water, trees and other vegetation provide ideal habitat for mosquitoes and birds known to carry the virus.

People can help reduce the number of mosquitoes near their homes by emptying items holding standing water like old tires, buckets, and flowerpots, and changing water in birdbaths, fountains, wading pools, and animal troughs at least twice a week. Mosquitoes only need a small amount of water to reproduce. Repair or replace screens on windows and doors to keep mosquitoes outside.

Avoiding mosquito bites is the best way to prevent infection. Use bug repellent and wear long pants and long sleeves outdoors at dawn and dusk when mosquitoes are most active to help avoid mosquito bites.

Most people infected with West Nile virus won’t become ill. About one in five people who are infected with the virus will develop a fever and other symptoms such as a headache, body aches, joint pains, vomiting, diarrhea, or rash that go away without getting medical treatment. About 1 in 150 people who are infected can have very serious neurological illness, which on rare occasions can cause permanent neurological effects or be fatal. People with certain medical conditions that affect the immune system, such as cancer, diabetes, hypertension, or kidney disease are at greater risk for serious illness. Updated West Nile virus information, prevention tips, and testing information are available online.

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