West Nile Virus

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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 Virus)
• Organ transplants (when a person gets an organ(s) from a person with West Nile Virus)
• Pregnancy (it can pass from mother to fetus)
• 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 like:

• Headache
• Fever
• Body aches
• Skin rash
• Swollen lymph glands
• Throwing up

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 can have:

• Bad headaches
• Coma
• Muscle weakness
• Confusion
• High fever
• Numbness
• 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 FDAapproved 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 the hospital.

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. Do not use on sunburned skin, cuts, rashes, or other skin conditions.
• 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:

Centers for Disease Control and Prevention (CDC)
www.cdc.gov

Call your state or local government

FDA Office of Women's Health
www.fda.gov/womens/
2007