How to Prevent Zika Virus Disease

Zika is a viral infection that is spread mostly through bites from infected mosquitoes. Mosquitoes that carry the Zika virus are common in warm and moist areas of the world. These areas are called tropical or subtropical areas. Zika virus can also spread through sexual contact, through a blood transfusion, and from a mother to her baby before or during birth.

How can Zika affect me?

For most people, Zika infection does not cause any symptoms, or it causes only mild symptoms that may include body aches, a rash, or a fever. In some cases, Zika infection may cause a nervous system disease called Guillain–Barré syndrome (GBS). Zika infection is most dangerous for pregnant women because the infection can cause severe birth defects or miscarriage.

What actions can I take to lower my risk?

There is no vaccine to prevent Zika. The best way to prevent the disease is to avoid infected mosquitoes and avoid exposure to body fluids that can spread the virus. Prevention is important for everyone. Because of the risk to unborn babies, taking precautions is especially important for pregnant women, women who are trying to get pregnant, and sexual partners of these women.

Try to avoid travel to high-risk areas

• Avoid traveling to areas where Zika is a risk. The locations where Zika is being reported change often. To identify high-risk areas, check the CDC travel website: www.cdc.gov/zika/geo  
• If you live in, or must travel to, any of the high-risk areas, take all precautions to avoid mosquito bites.
• Pregnant women, women who are trying to get pregnant, and sexual partners of these women should talk with their health care providers before and after traveling to a high-risk area.

Take steps to avoid mosquito bites

Unlike most types of mosquitoes, which bite only at night, the type of mosquito that carries Zika virus bites both at night and during the day. Take these steps to avoid mosquito bites when you are in a high-risk area:

• Wear loose clothing that covers your arms and legs.
• Limit your outdoor activities.
• Do not open windows unless they have window screens.
• Sleep under mosquito nets.
• Use insect repellent. The best insect repellents have:
  • DEET, picaridin, oil of lemon eucalyptus (OLE), or IR3535 in them.
  • Higher amounts of an active ingredient in them.
• Remember that insect repellents are safe to use during pregnancy.
• Do not use OLE on children who are younger than 3 years of age. Do not use insect repellent on babies who are younger than 2 months of age.
• Cover your child’s stroller with mosquito netting. Make sure netting fits snugly and that any loose netting does not cover your child’s mouth or nose. Do not use a blanket as a mosquito-protection cover.
• Do not apply insect repellent underneath clothing.
• If you are using sunscreen, apply the sunscreen before applying the insect repellent.
• Treat clothing with permethrin. Do not apply permethrin directly to your skin. Follow label directions for safe use.
• Get rid of standing water, where mosquitoes may reproduce. Standing water is often found in items such as buckets, bowls, animal food dishes, and flowerpots.

When you return from traveling to any high-risk area, continue taking actions to protect yourself against mosquito bites for 3 weeks, even if you show no signs of illness. This will prevent spreading Zika virus to uninfected mosquitoes.

Prevent sexual transmission

People can spread Zika to their sexual partners during vaginal, anal, or oral sex, or by sharing sexual devices. Many people with Zika do not develop symptoms, so a person could spread the disease without knowing that he or she is infected. The greatest risk is to women who are pregnant or who may become pregnant.

Couples can prevent sexual transmission of the virus by:

• Using condoms correctly during the entire duration of sexual activity, every time. This includes vaginal, anal, and oral sex.
• Not sharing sexual devices. Sharing increases your risk of being exposed to body fluid from another person.
• Avoiding all sexual activity until your health care provider says it is safe.

These precautions are especially important if you or your sexual partner has traveled to an area with Zika or has symptoms of Zika. Talk with your health care provider about your risk.

What should I know about donating blood?

To protect other people, you should not donate blood if you may have been exposed to Zika virus. Wait to donate blood until:

• 4 weeks after you have traveled to an area where Zika has been reported.
• 4 weeks after you have had symptoms of Zika.
• 4 weeks after you have had sexual contact with:
  • A person who has had Zika.
  • A person who has traveled to a high-risk area at any time during the 3 months before the sexual contact occurred. You must wait this long because Zika virus can live longer in semen than it can live in blood.

Where to find more information

• Centers for Disease Control and Prevention: www.cdc.gov/zika  

Contact a health care provider if:

• You are pregnant or trying to get pregnant and you are planning to travel to an area at high risk for Zika virus.
• You are pregnant or trying to get pregnant and your partner is traveling to a high-risk area.
• You have traveled to a high-risk area and are planning to donate blood.

Summary

• Zika is a viral infection spread mostly through bites from infected mosquitoes. It can also spread through sexual contact, through a blood transfusion, and from a mother to her baby before or during birth.
• Zika infection is most dangerous for pregnant women because the infection can cause severe birth defects or miscarriage.
• There is no vaccine to prevent Zika. The best way to prevent the disease is to avoid infected mosquitoes and avoid exposure to body fluids that can spread the virus.
• Talk to your health care provider if you are worried about Zika, especially if you are pregnant or trying to get pregnant and you or your partner has traveled to a high-risk area.