Zika virus is a mosquito-transmitted virus that generally causes no symptoms or mild illness, but is associated with microcephaly in infants whose mothers contract it during pregnancy. In January 2016, the US Centers for Disease Control and Prevention (CDC) issued a health advisory, travel alert and Morbidity and Mortality Weekly Report (MMWR) urging women who are pregnant to avoid countries where Zika virus transmission is ongoing. Women trying to become pregnant should consult with their healthcare providers before traveling to these areas and strictly follow steps to avoid mosquito bites during the trip.
Zika virus can be spread during sex by a man infected with Zika to his sex partners. We do not know how long the virus can stay in the semen of men who have had Zika, and how long the virus can be spread through sex. We do know that the virus can stay in semen longer than in blood.
To help prevent spreading Zika from sex, you should 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.