YAKIMA -- A 71-year-old Sunnyside woman's death last month has been confirmed as Washington's first fatality from West Nile virus, the state Department of Health announced Wednesday.

Last month, family members said they'd been told that Ruth Rosalee Rogers had died of the virus. However, health officials held off confirmation until a third and final test was completed by the Centers for Disease Control and Prevention.

On Wednesday, the state Health Department and the CDC did not identify Rogers, but confirmed that a 71-year-old Sunnyside woman had died of the virus.

Rogers died Sept. 19 at Yakima Regional Medical and Cardiac Center.

Family members said she hadn't even noticed she had a mosquito bite. They said she had a fever and loss of appetite after returning with her husband, Howard, from a trip to Denver on Sept. 1.

Her family physician suggested she get to a hospital. She was admitted to Yakima Regional on Sept. 4 and never left, Howard Rogers said.

Yakima County has confirmed 20 cases of the virus this year, and the Yakima Health District is awaiting confirmation on three other cases, a news release said.

Except for Rogers, all the others are recovering, the release said.

Yakima County has been a hot spot for West Nile virus. Last year, the county led the state with 26 confirmed cases in horses. The year before, there were eight horse cases statewide, all of them in Yakima County.

The virus is transmitted to humans through mosquito bites. Only one in five infected people develop symptoms of the virus, and the onset of the illness occurs anywhere from three to 14 days after being infected.

Symptoms include fever, headache, body aches, rash and swollen lymph nodes. A more serious form of the virus causes neck stiffness, disorientation, coma, tremors, convulsions, muscle weakness, paralysis or death.

For more information on mosquito-born illnesses like West Nile virus, visit www.yakimapublichealth.org.