Like HIV, the Zika virus can be transmitted through sexual intercourse and so women and men can become infected without being bitten by a mosquito. In 2016, the CDC confirmed
that Zika is transmissible through semen, by more than one form of sexual intercourse. In addition, the virus can survive in semen for prolonged periods, unlike in other bodily fluids. The CDC advises pregnant women to avoid travel to Zika-endemic regions, including several counties in Florida, except when absolutely necessary. Nevertheless, restraining from travel to these regions may not always protect a pregnant woman from infection if her sexual partner decides the opposite. If a pregnant woman’s sexual partner gets bit by a Zika-infected mosquito and engages her in intercourse, the partner may be able to transmit the infection to the pregnant woman. Because of this, the CDC advises individuals, especially in the case of pregnancy, to practice safe sex using condoms, or to abstain from sex completely. While the CDC states that, to date, there have not been any reports of female-to-female Zika virus transmission
via sexual intercourse, they believe that it “is biologically plausible.” On the other hand, semen has been confirmed
to carry the virus and transmit it via vaginal, oral, or anal intercourse, even if the male partner is asymptomatic.
Because Zika has been identified to remain in semen longer than it has been found to stay in any other body fluids and only 20% of those infected with the virus will present with symptoms, many of those infected will go undiagnosed and could unknowingly spread the virus to their partners. In addition, the challenge of identifying the source and location of Zika infection makes it more difficult to contain Zika.
The CDC and other health organizations, such as the US Food and Drug Administration (FDA) are actively working to stop Zika virus transmission. Since Zika can be transmitted via blood transfusion, all blood donations in the United States and Puerto Rico are tested for Zika virus. Unfortunately, “testing for tissue donors, including semen donors, is not currently available; however, tissue donors are asked travel history questions, and if they have traveled to or live in an area of active Zika virus transmission they would be determined ineligible under current FDA guidance.”
“CDC encourages women and their partners, in consultation with their healthcare providers, to consider this potential risk when trying to conceive.” In addition, the CDC recommends that healthcare providers notify their pregnant patients who may have been exposed to Zika-infected semen of the possibility and risk of contracting Zika.
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