Cascade County public health officials have confirmed the state’s first case of West Nile Virus in a human, the first in the county since 2018.

The virus is primarily spread to people by mosquito bites.

The human case follows the first confirmed WNV-positive mosquito sample that CCHD announced on Aug. 21.

West Nile Virus detected in Cascade County

The severity and symptoms of WNV can vary widely with about 80 percent experiencing no symptoms and up to 20 percent of infected persons can develop a mild illness called West Nile fever, which generally resolves itself without treatment, but dangerous brain infections such as encephalitis or meningitis can develop in 1 out of 150 people, according to the Cascade City-County Health Department.

Human case of West Nile Virus reported in Cascade County [2018]

Symptoms usually appear 3-14 days after exposure and may include headache, rash, high fever, stiff neck, mental confusion, muscle weakness, tremors, convulsions, coma, and paralysis. Individuals who develop any of these symptoms should see their healthcare provider immediately.

Cascade County residents are strongly encouraged to take steps to protect themselves and CCHD recommends the following 5 Ds:

• DEET: apply repellent containing an EPA-registered active ingredient, such as DEET, and follow the directions on the package.
• DUSK and DAWN: this is when mosquitoes are most active. Try to avoid outdoor activities during these times.
• DRAIN STANDING WATER: standing water is the perfect breeding ground for mosquitoes. Drain such areas around your home (gutters, pools, tires, buckets, water bowls, etc.).
• DRESS APPROPRIATELY: wear long-sleeved shirts, long pants, and socks.

Cascade County Weed and Mosquito Division has been conducting regular treatments for
mosquito larvae and adult mosquitoes and will continue to do so in addition to ongoing
surveillance and monitoring efforts.