West Nile Virus Questions Answered
9. How do health care providers test for West Nile virus?
If your doctor suspects you have a West Nile virus infection, he or she will send a sample of your blood to a lab for tests. The most common tests look for antibodies against the virus, showing that you've recently been infected.
If you have symptoms of more severe disease, your doctor may perform a spinal tap to collect spinal fluid. As with blood, the spinal fluid sample is sent to a lab for tests.
10. Who is at risk for getting West Nile virus infection?
Mosquitoes carrying West Nile virus are found in all of the lower 48 states. Mosquitoes are most plentiful in late summer. West Nile season usually peaks in August and September.
People who spend a lot of time outdoors are at highest risk of infection. The mosquitoes that transmit West Nile virus are most active at dawn and dusk. Being outdoors during those hours increases the risk of infection.
People over age 50 are more likely to develop symptoms of West Nile disease, but it's not clear whether older people are more susceptible to infection.
Infants are not at higher risk of West Nile virus infection. And pregnancy does not increase a woman's risk of infection.
11. Can you get West Nile encephalitis from another person?
No. West Nile encephalitis is not transmitted from person to person. For example, you cannot get West Nile virus from touching or kissing a person who has the disease or from a health care worker who has treated someone with the disease.
12. Where did West Nile virus come from?
West Nile virus was first detected in the U.S. in New York City in 1999. It is not known where the U.S. virus originated but it is most closely related to strains found in the Middle East.
13. Is West Nile virus seasonal in its occurrence?
In the U.S., West Nile virus cases occur primarily in the late summer or early fall. In southern climates, where temperatures are milder, West Nile virus can be transmitted year-round.