Yamhill County
Public Health

West Nile virus is carried by mosquitoes and can infect humans, horses, and birds. Humans can only get the virus from the bite of an infected mosquito; the disease does not spread from other animals to humans, or from person to person. Most infections are mild, with fever and flu-like symptoms, but severe infections may cause encephalitis (inflammation of the brain), and rarely, death.

The spread of the disease to humans can be controlled by preventing mosquito bites. Avoiding outdoor activities during peak mosquito biting times (dusk to dawn, April through October), use insect repellent, and drain standing water where mosquitoes breed.