A Walla Walla County man is the first Washington resident in 2014 known to have been infected with West Nile virus in our state. The man in his 20s was likely exposed near his home and was hospitalized. The infection was confirmed by testing at the Washington State Public Health Laboratories in Shoreline.

Two other Washington residents have been diagnosed with the infection this year, both with exposures in other states. A King County man in his 70s and a Grays Harbor woman in her 50s were infected with West Nile virus this year while traveling out of state. Additional reports of possible infections are currently under investigation.

“The mosquito samples that have tested positive for West Nile virus in eastern Washington this season are a reminder that the virus is here and we should protect ourselves,” said State Health Officer Dr. Kathy Lofy. “The best prevention is to avoid mosquito bites — at home and while traveling.”

So far, 34 mosquito samples have tested positive for West Nile virus in 2014, including Benton County (11), Franklin County (11), and Grant County (12). The number of positive mosquito samples detected this year has already surpassed the number found during the past three years, combined (28).

Year after year, south central Washington has been a “hot spot” for the virus, with most in-state acquired human and animal cases having been exposed in this area. Mosquito testing shows the virus is in our state, and the mosquito species that transmit the virus are found throughout Washington. Regardless of where you are, health officials recommend avoiding mosquito bites to help prevent getting infected.A few simple precautions can help reduce your chances of getting mosquito bites:

• Stay indoors around dawn and dusk when mosquitoes are most active.

• Use a mosquito repellent when spending time outdoors, and consider wearing long sleeves and pants when mosquitoes are most active.

• Be sure that door and window screens are in good condition so that mosquitoes cannot get indoors.

• Reduce mosquito habitat around the home by dumping standing or stagnant water in old buckets, cans, flower pots, or old tires, and frequently change water in birdbaths, pet dishes, and water troughs.

West Nile virus is primarily a bird disease, and often dead birds are an early sign that the disease is active in an area. People may report dead birds online to public health officials. So far this year no dead birds have been reported with the infection in the state.

Most people infected with West Nile virus will have no symptoms at all. Others may develop fever, headache, or body aches. For a small percentage of people, West Nile virus infection can be very serious, resulting in encephalitis, meningitis, or other complications. People over age 50 have the highest risk for serious illness.

Last year, only two human infections of West Nile virus were reported, and both were exposed out of state. During 2012, four cases were reported, two of which were in-state acquired while the other two were travel-associated. The state most active year was 2009, in which there were 38 human cases, 95 animal cases (including birds), and 364 positive mosquito samples. It’s impossible to predict what each year may bring, so it’s important to do things to prevent mosquito bites and protect yourself from West Nile virus infection.

More information is available on the agency’s West Nile virus information line, 1-866-78-VIRUS (1-866-788-4787) and on the West Nile virus website.