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West Nile Virus
West Nile Virus is an illness spread by mosquitoes. Sometimes, it can cause
serious infections of the brain, spinal cord and nerves. This is rare. Most
people who get West Nile Virus do not get sick. Others may have mild symptoms
such as fever, headache, and feeling tired. People are most likely to get
West Nile Virus in the late summer and early fall.
How can I get it?
Mosquitoes can feed on birds that have West Nile Virus. Infected mosquitoes
can bite and pass the disease to humans and animals.
In very rare cases, West Nile Virus can be spread through:
- Blood transfusions (when a person gets blood from a person with West Nile
- Organ transplants (when a person get organs from a person with West
- Pregnancy (it can pass from mother to unborn child)
- Breastfeeding (when an infant breastfeeds from a woman who has West
Nile Virus) West Nile Virus is not spread from one person to another by
touching or kissing.
What are the symptoms?
Most people do not notice any symptoms after getting West Nile Virus.
Some people can have West Nile Virus fever. These people notice mild symptoms
- throwing up
- swollen lymph glands
- body aches
- skin rash
About 1 in 150 people who get West Nile Virus can have serious problems
with their brain, spinal cord and nerves (nervous system). These people
- bad headaches
- muscle weakness
- high fever
- loss of eyesight
- stiff neck
- shaking and/or jerking movements
Call your doctor right away if you have these symptoms.
In rare cases, West Nile Virus can cause death or lasting health problems.
Who is most at risk?
Only a few mosquitoes carry West Nile Virus. For most people, the risk is low.
Some people have a higher risk. People who are outside a lot have a greater
chance of being bitten. People older than 50 are more likely to get very
sick if they get West Nile Virus. People who already have health problems
also have a greater risk.
Is there a shot (vaccine) or treatment?
At this time, there are no FDA-approved shots or medicines to stop or treat
West Nile Virus infection. Most people with mild symptoms get better without
any treatment. People with severe West Nile Virus infections may need to go to
Can you get tested for the West Nile Virus?
In July 2003, the FDA approved a blood test to help doctors find out if a
person has West Nile Virus.
How Can I Protect Myself?
Prevent Mosquito Bites:
- Use bug spray. Look for permethrin or DEET on the label. Read and follow
the directions. Do not use it on children less than 2 years old.
- If you use bug spray, wash your clothes before you wear them again.
- Get rid of standing water (flower pots, buckets, barrels, and tire swings)
Mosquitoes can breed in standing water.
- Change water in outdoor pet dishes and bird baths often.
- Keep children's wading pools empty and on their sides when not in use.
- Stay inside during times when there are a lot of mosquitoes
(evening or dusk until dawn).
- Wear long-sleeved shirts and long pants.
- Put screens on your windows and doors.
- Don't wear perfume or cologne when you go outside for a long time.
- Check to see if there is a mosquito control program in your area.
Report Dead Birds
Call your state or local health department if you find a dead bird.
To learn more:
Go to CDC
Call the American Mosquito Control Association at 1-732-932-0667.
Call the National Pesticide Information Center at 1-800-858-7378.
Source: FDA Get the Facts on West Nile
Adapted by Editorial Staff, July 2007
Last update, August 2008