Publication Summary

The West Nile virus, one of many mosquito-borne diseases, was first found in the northeastern United States in 1999. The virus can cause encephalitis in humans and some animals. Cases of encephalitis range from mild to very severe illnesses that, in a few cases, can be fatal.

The West Nile virus, one of many mosquito-borne diseases, was first found in the northeastern United States in 1999. The virus can cause encephalitis in humans and some animals. Cases of encephalitis range from mild to very severe illnesses that, in a few cases, can be fatal.

West Nile virus is most commonly spread by the bite of an infected mosquito and can infect many types of birds as well as horses and people. The virus is not believed to be spread from person to person or from animal to person. Mosquitoes pick up the virus by feeding on an infected bird. This fall, a dead raven tested positive for West Nile virus in the Newport area, just north of Spokane near the Idaho border.

Homeowners, local government officials, and other members of the public are wondering what is being done to halt the spread of the virus and what, if anything, they can do. The state departments of Ecology, Health, Agriculture, Fish & Wildlife and Natural Resources have been working together to provide a coordinated response. The Department of Health (DOH) has taken the lead to develop an emergency response plan and is coordinating surveillance activities designed to detect the West Nile virus. Washington′s surveillance is part of a nationwide effort spearheaded by the federal Centers for Disease Control and Prevention to track the spread of West Nile virus. Steps that homeowners can take and other links can be found on the DOH website.

The application of insecticides is regulated by the Washington State Departments of Ecology (Ecology) and Agriculture (WSDA). WSDA oversees label compliance and issues professional licenses to those who apply pesticides, while Ecology issues permits for uses of aquatic pesticides to assure water quality is protected. Note: Ecology′s permit provides that a state or local health officer, in agreement with Ecology, may order temporary suspension of permit conditions to protect public health in the event of a mosquito-borne disease outbreak.

Under most controlled circumstances, emergency provisions will not be necessary. This Focus sheet clarifies Ecology′s role in permitting the use of insecticides as Washington attempts to control and minimize the effects of the West Nile virus.