ELLENSBURG, Wash. -- The death of an Ellensburg police officer appears to be the second hantavirus infection in Washington in less than a week, and homeowners should be careful with fall cleaning, a state epidemiologist said Tuesday.

Sgt. Nelson Ng, 34, died Friday of hantavirus pulmonary syndrome, the Yakima County coroner reported. Rebecca Baer, zoonotic disease epidemiologist with the state Health Department, said Ng's death remains under investigation but looks like it could be from hantavirus.

Testing by the state health laboratory in Shoreline and the federal Centers for Disease Control and Prevention should be completed by the end of this week or early next week, Baer said.

A Bellingham resident whose name has not been released was sent home from the hospital to finish recuperating last week after being treated for hantavirus, Baer said.

The virus spreads through contact with mouse saliva, urine or droppings. In the western United States, the deer mouse is the main carrier of hantavirus, but health officials advise avoiding contact with all wild rodents.

On average, one to five cases of the virus have been reported in Washington annually since the illness was identified in 1993. Of 35 confirmed state cases since 1993, 11 people have died.

Two cases in less than a month would be more of a coincidence than anything else, Baer said.

"It can happen any time of year," she added.

The disease has been fatal in 31 percent of cases in Washington state and there is no cure, only treatment of the symptoms -- especially oxygen to aid breathing -- so precautions should be taken to avoid the disease, health officials said.

"The main lesson learned is we want to make sure to prevent this illness, and we can," Baer said.

One measure is to avoid sweeping or vacuuming, which may stir up dust, when cleaning an outdoor shed or indoor area that may have been infested by any kind of mice.

Instead, health officials say, a bleach solution of 1 1/2 cups bleach to 1 gallon of water should be sprayed to thoroughly soak the area for 10 minutes, after which the droppings can be removed with a damp towel and the area mopped with the bleach solution.

Campers should avoid pitching tents or putting sleeping bags near rodent droppings or burrows, and food for animals and humans should be kept in rodent-proof containers both indoors and outside.

Deer mice can be found all over the state and there is no season for hantavirus. People who experience fever, flulike symptoms and shortness of breath after cleaning a shed or basement where they may have been exposed to mouse droppings should see a doctor, Baer said.