KENNEWICK – A man in Franklin County is the first person in Washington state to be diagnosed with West Nile virus this year.
The man, in his 50s, was hospitalized but is now at home.
The Benton Franklin Health District, which announced the case Friday afternoon, said it is unknown where he contracted it.
He lives in Franklin County but works in Walla Walla County.
No infected mosquitoes have been reported in either county, but infected mosquitoes have been found 24 samples from central and eastern Washington state this year.
Seven were collected in Benton County, including in Richland, Kennewick and West Richland. Two were in Yakima County and 15 were in Grant County.
Spread by mosquitoes
“Most cases of West Nile virus are mild,” said Dr. Amy Person, health officer for Benton and Franklin counties. “However, serious illness and death are also possible.”
Eleven deaths due to the virus have been reported in the nation this year.
An estimated one in 150 people infected with the virus will develop a serious illness that can cause permanent damage to the central nervous system or be fatal.
The virus is most often spread to people and animals such as horses by the bite of an infected mosquito. Mosquitoes become infected when they feed on infected birds.
No infected birds or horses have been reported in Washington state this year.
The risk of West Nile virus remains high for Tri-City-area residents until mosquitoes go away after the first hard frost, according to the health district. The season can last into early October.
How to avoid infection
There is a vaccine for horses, but not for people. Instead, people must take steps to help prevent an infection, said the health district.
It recommends staying indoors during the times that mosquitoes are most likely to be present and biting, dusk and dawn.
People who go outside when mosquitoes are present should wear long sleeves, pants and a hat.
They also should use an Environmental Protection Agency-approved insect repellent. They they should have the ingredients DEET, picaridin, PMD, IR3535 or oil of lemon eucalyptus.
Leave windows and doors closed at night unless they have tight-fitting screens.
Drain any standing water on your property at least once a week to keep mosquitoes from breeding. They breed in water in outdoor containers, tires, buckets and other small amounts of standing water.