What is West Nile virus?
West Nile virus (WNV), which causes West Nile fever, encephalitis and meningitis, is a mosquito-borne virus that first appeared in the United States in 1999. After being found in bird populations in the metropolitan New York area, it has since spread across the United States. The first human infection by West Nile Virus in Washington state occurred in 2006.
How is West Nile Virus transmitted?
By mosquitoes that feed on birds infected with the virus.
What are the risks to humans?
- 80% of people who become infected never get symptoms.
- People who become ill develop symptoms 3 to 14 days after being infected.
- About 1 in 5 infected people develop West Nile fever, a flu-like illness lasting a few days. These persons recover fully and do not require hospital care.
- Less than 1% of infected people develop encephalitis or meningitis with symptoms of high fever, neck stiffness, confusion, disorientation, coma, tremors, convulsions, muscle weakness and paralysis.
- Persons who are older than 50 years, particularly those who are greater than 70 years of age, have a higher risk of developing more serious symptoms.
For more information on human health risks, please visit King County's West Nile virus fact sheet.
What can residents do to protect themselves?
Protect yourself and your family by controlling mosquito populations on your property and preventing exposure to mosquitoes. Following the tips below will help you reduce your risks:
- Make sure window and door screens are "bug tight." Repair or replace if needed.
- Stay indoors at dawn and dusk when mosquitoes are the most active.
- Wear a long sleeve shirt, long pants and a hat when going into mosquito-infested areas.
- Use mosquito repellant, when necessary, and carefully follow directions on the label.
- Empty anything that holds standing water—old tires, buckets, plastic covers, and toys.
- Change water in your birdbaths, fountains, wading pools and animal troughs weekly.
- Make sure roof gutters drain properly, and clean clogged gutters in the spring and fall.
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
For more tips on how to prevent your property from becoming a mosquito breeding ground, please visit King County's prevention tips for homeowners.
Find more information on how to protect yourself and your family from mosquitoes here.
What are the risks to animals?
West Nile virus affects horses, mules, donkeys and other equines much more often than other animals. A vaccination for horses is available; horse owners should contact their veterinarian for advice on West Nile Virus.
How do I report a dead bird?
Report dead crows to the Public Health Seattle and King County at (206) 205-4394 or online.
For more information, please visit King County's website.
What is the City of Kirkland doing in response to West Nile Virus?
The City of Kirkland is educating City residents and employees about personal protection measures. Educational materials are being distributed through utility bills, at Kirkland City Hall, and at special events.
Who do I contact for more information?
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