What is Zika virus?

Zika is a viral infection most commonly spread to humans by mosquitoes.

You're more likely to get the virus if you travel to parts of the world where it's more common. This includes parts of South America, Central America, Mexico, the Caribbean, and the Pacific Islands.

Most people infected with Zika don't have any symptoms. When symptoms are present, they include fever, rash, painful joints, headache, and red eyes (conjunctivitis).

Zika infection is much more serious for anyone who is pregnant because it can cause birth defects and other problems during pregnancy.

Experts have found that infection with Zika virus can cause Guillain-Barre syndrome (GBS) in a small number of people who get it.

How is it spread?

Zika is most often spread through a bite from an infected mosquito. It can also be spread through sexual contact with body fluids, such as blood, semen, saliva, and vaginal fluids. Even if the infected person does not have symptoms, they can spread the virus.

Travelers who have Zika can spread it when they come home or travel to another area. People who have Zika need protection from getting more mosquito bites. If a mosquito bites an infected person, the mosquito becomes infected with the virus and can then pass it to other people.

If someone who is pregnant gets infected with Zika, it can be passed to the baby (fetus).

What are the symptoms?

Most people infected with Zika don't have any symptoms. When there are symptoms, they are usually mild. They most often start within a week after the bite. The main symptoms may include:

• Fever.
• Rash.
• Painful joints.
• Red eyes (conjunctivitis).

Some people also have a headache and muscle pain.

How is Zika virus treated?

There is no treatment for Zika virus. Symptoms usually go away on their own after about a week.

Treating your symptoms may help you feel better.

• Get extra rest.
• To prevent dehydration, drink plenty of fluids. Choose water and other clear liquids until you feel better. If you have kidney, heart, or liver disease and have to limit fluids, talk with your doctor before you increase the amount of fluids you drink.
• Ask your doctor before you take an over-the-counter pain medicine, such as acetaminophen (Tylenol), ibuprofen (Advil, Motrin), or naproxen (Aleve). Be safe with medicines. Read and follow all instructions on the label.
• Do not take two or more pain medicines at the same time unless the doctor told you to. Many pain medicines have acetaminophen, which is Tylenol. Too much acetaminophen (Tylenol) can be harmful.

What if you're pregnant or thinking about becoming pregnant?

Babies born to someone who has the Zika virus are at risk for birth defects, including microcephaly (say "my-kroh-SEF-uh-lee"). Microcephaly means that the baby's head is smaller than normal. It causes problems in how the baby's brain develops.

The Centers for Disease Control and Prevention (CDC) recommends that anyone who is pregnant should wait until after they give birth before traveling to areas where there are Zika outbreaks.

Zika can be spread through sexual contact even if the infected person does not have symptoms. If your partner has been to an area where there is a Zika outbreak, the CDC recommends that you delay having sex until the baby is born or use condoms every time you have vaginal, anal, and oral sex.

If you are pregnant and have traveled to an area with an outbreak of Zika, talk to your doctor about additional tests you may need.

If you are thinking about becoming pregnant, you and your partner should talk to your doctor about the risk of traveling to areas where there are Zika outbreaks. Experts recommend that you delay pregnancy if you or your partner has been to an area with ongoing Zika transmission.

After returning from an area with risk of Zika:

• If you have no symptoms, you should wait at least 2 months before getting pregnant or at least 3 months before getting your partner pregnant.
• If you want to get pregnant and you do have symptoms, you should wait at least 2 months from the start of your symptoms or the date you were diagnosed with Zika. If you want to get your partner pregnant, you should wait at least 3 months from the start of your symptoms or the date you were diagnosed with Zika.

How can you help prevent Zika virus?

There is no vaccine to prevent Zika. But you can protect yourself from mosquito bites, especially when you travel.

• Wear long pants and long-sleeved shirts. Some outdoor-clothing stores sell clothing already treated with insect repellent.
• Use insect repellents recommended by the Environmental Protection Agency (EPA).
  • Use one with DEET, picaridin, IR3535, oil of lemon eucalyptus, paramenthane-diol, or 2-undecanone. Repellents are available in varying strengths. Read and follow all instructions on the label, especially for how to use them on children.
  • Spray clothing with DEET. Mosquitoes may bite through thin clothing. (Remember that DEET can damage plastic, such as watch crystals, eyeglass frames, and some synthetic fabrics.)
• Sleep under bed nets (mosquito netting).
• Use flying-insect spray indoors around sleeping areas.
• Avoid areas where there is an outbreak, especially if you are pregnant.

If you have been to an area where there is a Zika outbreak or if you do get infected with Zika, protect yourself from mosquito bites for at least 3 weeks to prevent the spread of the virus.

The Zika virus can be spread through vaginal, anal, and oral sex and the sharing of sex toys. This will help prevent the virus from spreading to other people:

• If you're biologically male, you should use condoms or not have sex for at least 3 months after symptoms begin.
• If you're biologically female, you should use condoms or not have sex for at least 2 months after symptoms begin. Zika can also cause problems during a pregnancy or in the baby (fetus) so it is also important to take precautions from getting pregnant.

To learn more

The most current information about Zika is available from the U.S. Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO). If you are planning international travel, you can learn about the risk of Zika in the area you're traveling to by:

• Visiting the CDC website at www.cdc.gov/zika or by calling their toll-free phone number (1-800-232-4636).
• Contacting your doctor or local health department.