West Nile Virus Facts
What is the West Nile virus?
West Nile virus causes an infection that can lead to inflammation of the brain (encephalitis), the spinal cord (myelitis), or the tissues surrounding it and the spinal cord (meningitis).
Can humans get the West Nile virus?
Yes. When there is hot, dry summer weather, the chances of getting West Nile virus are particularly high.
How do humans get the West Nile virus?
Humans typically contract the West Nile virus through an infected mosquito bite. Symptoms typically appear 3-14 days after a bite from the infected mosquito. People over age 50 are more likely to become severely ill as a result of such a bite.
How does West Nile virus spread to humans?
West Nile virus is not spread through casual contact such as touching or kissing a person with the virus.
- Infected Mosquitoes - Most often, WNV is spread by the bite of an infected mosquito. Mosquitoes become infected when they feed on infected birds. Infected mosquitoes can then spread WNV to humans and other animals when they bite.
- Transfusions, Transplants - In a very small number of cases, WNV also has been spread through blood transfusions, organ transplants. All donated blood is checked for WNV before being used. The risk of getting WNV through blood transfusions and organ transplants is very small. Don't avoid needed surgery.
- Mother-to-Child - In a very small number of cases, WNV also has been spread through breastfeeding and even during pregnancy from mother to baby.
- If you find a dead bird - don't handle the body with your bare hands. Contact your local health department for instructions on reporting and disposing of the body. They may tell you to dispose of the bird after they log your report. Follow their instructions.
What are the signs and symptoms of the West Nile virus?
Eighty percent of all infected humans show no symptoms at all. Twenty percent have less severe symptoms, including fever, headache, body aches, vomiting, swollen glands, and rashes. Some of the most serious symptoms of the virus, which appear in only about 1 out of every 150 people, include tremors, convulsions, muscle weakness, vision loss, numbness, paralysis, and even comas.
Treating West Nile virus in humans
There is no one prescribed treatment for West Nile virus. Symptoms are often treated individually, but most cases do not require any treatment at all. Individuals with severe symptoms should seek medical attention immediately.
Prevent exposure to West Nile virus
Anyone who goes outdoors is at risk for West Nile. According to the CDC (Center for Disease Control), there are steps you can take to avoid virus-carrying mosquitoes.
- Stay indoors at dusk and dawn - Early morning and evening are when mosquitoes are most active. Also use an insect repellent.
- Clean up your environment - Remove any standing water in flower pots, buckets, barrels, bird baths, and pet dishes. These are all potential areas for breeding grounds for mosquitos. Also, keep children's wading pools empty when they're not in use.
- Always wear protection - Anytime you're outdoors during the summer months, wear insect repellent. Cover your arms with long sleeves, and legs with long pants.
Information available at EveryDayHealth.com and CDC.gov, 2012