As we have learned more about the Zika virus over the last 18 months, we have come to recognize that not only can it be spread through a bite from an infected mosquito, but also through sexual contact. This can be from a woman to a man (few documented cases), and much more commonly, from a man to a woman.
Unfortunately, the majority of those infected with Zika are asymptomatic, therefore sexual transmission can occur with no known symptoms. It has also been detected in saliva but there is no evidence that it can be transmitted from kissing.
Because Zika can be detected in semen for up to six months, the current Centers for Disease Control and Prevention (CDC) recommendations state that pregnant women with sexual partners who live in or traveled to an area with risk of Zika should use barrier protection, such as condoms, during sex, or abstain from sex during the duration of their pregnancy.
For women who are trying to get pregnant, they should abstain from having sex for at least eight weeks after traveling to a Zika-afflicted region even if they have no symptoms, or wait at least eight weeks after illness onset (or diagnosis via blood test).
For male partners, the recommendations are to wait at least six months after travel in absence of symptoms, or at least six months after illness onset if the male had Zika.