What we know
- No vaccine exists to prevent Zika virus disease (Zika).
- Zika virus is mostly spread through the bite of an infected mosquito. Prevent Zika by avoiding mosquito bites (see below).
- Mosquitoes that spread Zika virus bite mostly during the daytime.
- Mosquitoes that spread Zika virus also spread dengue and chikungunya viruses.
- Zika virus can be spread during sex by a man infected with Zika to his sex partners.
Steps to prevent mosquito bites
When in areas with Zika and other diseases spread by mosquitoes, take the following steps[PDF – 2 pages]:
- Wear long-sleeved shirts and long pants.
- Stay in places with air conditioning and window and door screens to keep mosquitoes outside.
- Take steps to control mosquitoes inside and outside your home.
- Sleep under a mosquito bed net if you are overseas or outside and are not able to protect yourself from mosquito bites.
- Use Environmental Protection Agency (EPA)-registered insect repellents with one of the following active ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus, or para-menthane-diol. Choosing an EPA-registered repellent ensures the EPA has evaluated the product for effectiveness. When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breast-feeding women.
- Always follow the product label instructions.
- Reapply insect repellent as directed.
- Do not spray repellent on the skin under clothing.
- If you are also using sunscreen, apply sunscreen before applying insect repellent.
- To protect your child from mosquito bites:
- Do not use insect repellent on babies younger than 2 months old.
- Do not use products containing oil of lemon eucalyptus or para-menthane-diol on children younger than 3 years old.
- Dress your child in clothing that covers arms and legs.
- Cover crib, stroller, and baby carrier with mosquito netting.
- Do not apply insect repellent onto a child’s hands, eyes, mouth, and cut or irritated skin.
- Adults: Spray insect repellent onto your hands and then apply to a child’s face.
- Treat clothing and gear with permethrin or purchase permethrin-treated items.
- Treated clothing remains protective after multiple washings. See product information to learn how long the protection will last.
- If treating items yourself, follow the product instructions carefully.
- Do NOT use permethrin products directly on skin. They are intended to treat clothing.
Even if they do not feel sick, travelers returning to the United States from an area with Zika should take steps to prevent mosquito bites for 3 weeks. These steps will prevent them from passing Zika to mosquitoes that could spread the virus to other people.
If you have Zika, protect others from getting sick
- During the first week of infection, Zika virus can be found in the blood and passed from an infected person to another mosquito through mosquito bites. An infected mosquito can then spread the virus to other people.
- To help prevent others from getting sick, strictly follow steps to prevent mosquito bites[PDF – 2 pages] during the first week of illness.
- A man with Zika virus can pass it to his female or male sex partners.
- Zika virus can stay in semen longer than in blood, but we don’t know exactly how long Zika stays in semen.
- To help prevent spreading Zika from sex, you can use condoms, correctly from start to finish, every time you have sex. This includes vaginal, anal, and oral (mouth-to-penis) sex. Not having sex is the only way to be sure that someone does not get sexually transmitted Zika virus.
If you are a man who lives in or has traveled to an area with Zika
- If your partner is pregnant, either use condoms correctly (warning: this link contains sexually graphic images) from start to finish, every time you have vaginal, anal, and oral (mouth-to-penis) sex, or do not have sex during the pregnancy.
- Even if they do not feel sick, travelers returning to the United States from an area with Zika should take steps to prevent mosquito bites[PDF – 2 pages] for 3 weeks so they do not spread Zika to mosquitoes that could spread the virus to other people.
If you are concerned about getting Zika from a male sex partner
- You can use condoms correctly from start to finish, every time you have vaginal, anal, and oral (mouth-to-penis) sex. Condoms also prevent HIV and other STDs. Not having sex is the only way to be sure that you do not get sexually transmitted Zika virus.
- Pregnant women should talk to a doctor or other healthcare provider if they or their male sex partners recently traveled to an area with Zika, even if they don’t feel sick.
Information for travelers
- Traveling? Visit CDC’s Travelers Health website to see if the country you plan to visit has any travel health notices.
- Even if they do not feel sick, travelers returning to the United States from an area with Zika should take steps to prevent mosquito bites for 3 weeks so they do not spread Zika to mosquitoes that could spread the virus to other people.