King County officials announced Tuesday that a dead crow found in Kirkland on Sept. 15 tested positive for West Nile Virus.

This is the first bird to test positive for the virus in King County in 2008, officials said in a press release. They warned that residents could still potentially become infected this year.

“While the days are growing cooler and there may be fewer mosquitoes around, this West Nile-positive bird is a reminder that it’s still important to protect yourself against mosquito bites,” said Dr. David Fleming, director and health officer for Public Health – Seattle & King County. “The risk of contracting West Nile virus is not yet over for this season.”

The bird was collected through Public Health’s Zoonotic Disease Program, via testing at the Washington Animal Disease Diagnostic Laboratory in Pullman. The program is aimed at protecting the public from insect and animal-borne diseases, and surveillance activities include tracking where birds die in King County, testing selected birds, trapping and testing mosquitoes and coordinating West Nile prevention efforts throughout the county.

More than 1,300 dead birds have been reported this year to Public Health, and 187 mosquito pools have been tested so far this year. Crows and jays are important indicators that West Nile is in a community, because they tend to die quickly from the disease. The bird found in Kirkland that tested positive is the first bird since October, 2006, when Public Health found six positive birds and one horse.

Another dead crow that also tested positive for the virus was also found recently in Thurston County.

Testing of dead birds will end in late October, but King County residents are asked to report dead birds year-round by calling Public Health at 206-205-4394 or by reporting them online at www.metrokc.gov/health/westnile/deadbird.htm.

In 2008, more than 700 people nationwide have come down with symptoms of West Nile virus, and 11 people have died. Washington state has had multiple birds, mosquitoes and horses test positive for West Nile. Two Washington residents, one of whom lives in King County, are being considered “probable” for West Nile virus, pending further testing. Also a King County resident who donated blood was found to have West Nile, but officials believe all three individuals contracted West Nile virus outside of King County.

The virus spreads to people after mosquitoes have bitten infected birds. West Nile can cause serious illness, particularly in older adults. West Nile virus is primarily a bird disease, and crows are especially susceptible. Mosquitoes become infected by feeding on an infected bird and can pass the virus to humans, horses or other animals when they bite. West Nile virus is not spread by person-to-person contact, nor is it transmitted directly from birds or other animals to people.

While rains and colder temperatures may have reduced the number of mosquitoes, the public is still urged to minimize the chances that they will be bitten by a mosquito.

Prevention tips from Public Health include:

• Tip out sources of standing water such as barrels, buckets and wheelbarrows, plastic tarps, toys, cans or plant saucers, tires, birdbaths, bottles, wading pools

• Repair ripped windows and door screens and make sure they fit tight

• When mosquitoes are out – often at dawn and dusk – wear long sleeve shirts and long pants.

• Consider using an insect repellent. Repellents containing the chemical DEET are known to be very effective, as are products containing picaridin or oil of lemon eucalyptus. It is important to read the label and follow the instructions on the label carefully.

West Nile virus symptoms

Most people who become infected with West Nile virus do not experience any symptoms and are not ill. About 20 percent of people infected will develop symptoms including fever, headache, body aches and occasionally swollen lymph glands or a rash, and can be ill for several weeks. In fewer than 1 in 150 cases, West Nile virus may cause encephalitis, or inflammation of the brain. These cases are serious, and require hospitalization and supportive care. There is no vaccine for West Nile virus in humans. Public Health advises health care providers throughout the county how to detect possible West Nile cases in humans, and how to get patients with possible West Nile virus infection tested.

Horses are at high risk for West Nile virus. Horse owners are urged to contact their veterinarian about a vaccine for West Nile virus. Other animals, such as cats and dogs, are very unlikely to become ill from West Nile virus.

For more information:

• Public Health – Seattle & King County: www.metrokc.gov/health/westnile

• Public Health – Seattle & King County West Nile hotline: 206-205-3883

• To report a dead crow: 206-205-4394 (Monday through Friday, 8:00 a.m. to 5:00 p.m.)

• State Department of Health www.doh.wa.gov/ehp/ts/Zoo/WNV/WNV.html

• The CDC has an insect repellent use and safety page: www.cdc.gov/ncidod/dvbid/westnile/qa/insect_repellent.htm.