West Nile Virus
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No people or animals have tested positive for West Nile Virus in 2012 in King County. However, two human cases were confirmed in other areas of Washington State in 2012--one in Pierce County and one in Yakima. For information on West Nile Virus in Washington State, visit the Department of Health and Public Health-Seattle & King County.
It's always a good idea to eliminate water sources around your home where mosquitoes can breed and to avoid mosquito bites.
Protect yourself from mosquito bites
Only nine species of mosquitoes out of more than 50 in Washington have the potential to transmit the West Nile virus and, according to the federal Centers for Disease Control, human illness from the virus is rare, even in areas where the virus has been reported. Even so, avoiding mosquito bites is a safe course of action.
- Reduce the places available for mosquitoes to lay their eggs by eliminating standing water sources from around your home. (Mosquitoes need stagnant water for a minimum of seven days to complete their life cycle.)
- Change the water in your birdbaths, fountains, wading pools and animal troughs once a week.
- Make sure roof gutters drain properly.
- When possible, wear a long-sleeved shirt, long pants and a hat when going into areas where mosquitoes have been observed.
- Consider staying indoors at dawn, dusk and in the early evening, which are peak mosquito biting times.
- Make sure windows and door screens are “bug tight.” Repair or replace if needed.
- Consider applying insect repellent containing DEET (N,N-diethyl-meta-toluamide) or Picaridin when you're outdoors, especially at dawn and dusk.
- Do not apply chemicals or other pollutants to streams, lakes or wetlands (or to water that may flow into them). Remember that natural predators such as dragonflies, fish and frogs help reduce mosquito populations.
What Bellevue is doing
- The city is eliminating sources of stagnant water, when possible, that provide mosquito breeding grounds.
- Bellevue has a number of natural wetland areas where mosquitoes could breed; however, wetlands also have natural predators such as fish, dragonflies and frogs that reduce mosquitoes. To protect the ecosystem of the city, staff will monitor these areas and work with regional agencies on potential solutions, should the need arise.
- The city is also checking for mosquito larva in street drains on a request basis.
- If testing demonstrates the presence of mosquito larva, Bellevue will have a contractor apply a larvicide in limited and targeted public facilities and areas of stagnant water to control immature mosquitoes before they emerge as adults. This practice is in accordance with Public Health - Seattle & King County's West Nile Virus response plan.
- Bellevue will work with the state and local public health agencies to support their surveillance and education outreach actions.
- If deemed necessary, Bellevue will also implement additional control actions on public city property and facilities.
For More Information
The federal Centers for Disease Control, state Department of Health and Public Health-Seattle & King County are the experts in this area and the sources of information about the virus. For updated recorded information, call the King County West Nile Virus hotline (206-205-3883) or the state hotline (1-866-78VIRUS).
Crows are particularly susceptible to West Nile Virus. If you find a dead crow on your property, call Public Health at 206-205-4394. Fo more information on West Nile Virus or to report a dead bird, visit
King County's website. If you see a heavily infested area of mosquitoes, you can also call Public Health. They are tracking specific locations that seem to be mosquito problem areas.