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West Nile Virus Questions & Answers

What is West Nile virus?

West Nile virus can be a serious, even fatal, illness. It can affect people, horses, certain types of birds, and other animals. In 1999, West Nile virus first appeared in the United States in New York City. Since that time, it has spread rapidly throughout the country. In Washington, the first cases of people becoming ill from West Nile virus were reported in 2006.

For an overview of West Nile virus, visit the Centers for Disease Control and Prevention.

How is it spread?

West Nile virus is almost always spread to people by the bite of an infected mosquito. Mosquitoes become infected after feeding on birds that carry the virus. There is no evidence that West Nile virus can be spread by direct contact with infected people or animals. 

As we learn more about West Nile virus, other routes of infection are being discovered. For more information, visit the Centers for Disease Control and Prevention. 

Who is at risk?

The risk of getting West Nile virus is very low, but anyone can become infected. People over 50 years of age have the highest risk of serious illness.

What are the symptoms?

Most people who are infected with West Nile virus will not get sick. About 1 in 5 people infected will have mild symptoms such as fever, headache, and body aches. Even fewer, about 1 in 150 people infected, will have more severe symptoms. Severe symptoms may include headache, high fever, neck stiffness, stupor, disorientation, tremors, convulsions, muscle weakness, paralysis, and coma. If you have any of these symptoms, contact your health care provider. 

What is West Nile virus?

How is it spread?

Who is at risk?

What are the symptoms?

How can I protect myself?

What is an effective mosquito repellent?

How do I report a dead bird?

What is being done in Washington?