Zika virus can be passed from a pregnant woman to her fetus during pregnancy or to her baby around the time of birth. Zika virus infection during pregnancy can cause microcephaly (a birth defect where a baby’s head and brain are smaller than babies of the same age and sex) and other severe brain defects.
- If you are pregnant, do not travel to areas with Zika.
- If you must travel to an area with Zika, talk to your doctor or other healthcare provider first and strictly follow steps to prevent mosquito bites during the trip.
- If you have a partner who lives in or has traveled to an area with Zika, use condoms from start to finish, every time you have sex (vaginal, anal, or oral) to protect against infection or do not have sex during the pregnancy.
- Talk with your healthcare provider before traveling to areas with Zika and strictly follow steps to prevent mosquito bites during the trip.
Zika virus spreads in several ways:
- Through mosquito bites. This is the most common way Zika spreads. You can get infected from a mosquito that carries the Zika virus, and a mosquito can get the virus by biting an infected person. The mosquito can then pass the virus by biting someone else. Zika infection usually stays in a person’s blood for about a week after getting infected. The mosquitoes that carry Zika virus can live both inside and outside. They’re called day biters because they bite most often during the day, but they also bite at night.
- By passing it to your baby during pregnancy and birth. More research is needed, but experts think Zika virus can pass through the placenta to your baby. The placenta grows in your uterus (womb) and supplies your baby with food and oxygen through the umbilical cord.
- Through sex with an infected person. During sex, an infected male can pass Zika through semen. Semen contains sperm, which is what fertilizes an egg to get a woman pregnant. An infected woman can pass Zika to her partner during sex through vaginal fluids or blood from her menstrual period.
- Through infected blood and body tissue, including semen. You may come in contact with infected blood or body tissue in a health care setting (like a laboratory) or if you have a blood transfusion. A blood transfusion is when you have new blood put into your body.