Seven more birds have tested positive for the West Nile Virus in Washington since the Island County Health Department confirmed the death of one crow on Whidbey Island due to the virus last week.

The birds were collected in Snohomish, King, Yakima and Cowlitz counties.

Two of the birds in King County were from Seattle and one was from Kent, according to the Washington State Department of Health. The Snohomish bird was found near Everett. In Cowlitz County, the bird was found near Kelso. The two birds in Yakima County were from Union Gap and Yakima.

The virus is spreading fast.

“Heretofore, before this past summer, no animal in Washington state had contracted WNV from within the state,” said Dr. Roger Case, Island County health officer.

“Now, nine birds, five horses and three humans have contracted WNV within our state, which means the five mosquito species identified in Island County as vectors for WNV have a ready source of the virus to pass along to humans and other animals,” he said.

The tests were done at the Washington Animal Disease Diagnostic Laboratory based at Washington State University.

This brings the total number of infected birds to nine this season. There have also been three confirmed human cases that were acquired in-state, the first such cases in Washington.

“Testing for West Nile virus in mosquitoes, horses and dead birds helps show where the virus is active,” said Dorothy Tibbetts, manager of the agency’s zoonotic disease program.

“These tests show West Nile is now part of our landscape. We’re in the tail-end of the West Nile virus season, but we will likely see more cases in the environment next year,” she added.

West Nile virus is primarily a bird disease. Crows, ravens, jays and magpies are especially susceptible. Mosquitoes become infected by feeding on an infected bird and can pass the virus to humans, horses or other hosts.

Because the virus is also a threat to humans, protection against mosquito bites has to be taken more seriously, now that the virus is known to be present, Case said.

“While WNV has not been a significant problem in our country — most folks testing positive for the antibody for WNV are not even aware they have at some time had WNV infection — a small number have serious problems with the disease and experience polio-like residual effects; and a far smaller number of individuals do die of the disease,” Case said.

“It’s a crap shoot, so to speak, as to who does and who does not have problems from WNV,” he said.

“The best solution is to avoid mosquito bites,” Case said.

Many islanders who live surrounded by water and wetlands underestimate the threat.

Case recalled the principal at the elementary school on Camano Island telling stories about the children coming in from recess with mosquito bites all over them at the start of school this year.

The birds were collected in early October as part of the state Department of Health monitoring program. Many local and state agencies as well as private volunteer groups are participating in the monitoring.

West Nile virus has spread across the country since it was first detected in 1999. Tibbetts said mosquitoes typically are active in Washington well into the fall, and she urged people to continue reporting dead birds to local health agencies for possible collection.

“We put a lot of effort into monitoring and tracking the disease here because we know people are concerned,” Tibbetts said. “The best protection against West Nile infection is to avoid mosquito bites.”

The county has a number of programs in effect over the last year to combat the problem including its tire collection program. Getting rid of old tires and other containers around homes where water can accumulate and serve as a breeding ground for mosquitoes, helps contain the spread of the virus.

More information on West Nile virus is available on the Department of Health Website at www.doh.wa.gov/WNV and from The Centers for Disease Control and Prevention at www.cdc.gov/ncidod/dvbid/westnile/