Why Safe Sex Could Protect You From Zika

Zika virus can be sexually transmitted, may persist in sperm even after negative blood tests

/ Author:  / Reviewed by: Jennifer Gershman, PharmD, CPh

(RxWiki News) Zika is primarily spread by mosquitoes. But that may not be the only way to contract the virus.


According to a new report from the Centers for Disease Control and Prevention (CDC), Zika virus can be sexually-transmitted in some cases. Current information about the potential for sexual transmission is based on three known cases.

The first case showed a probable transmission of Zika from an infected man to a woman, in which the two engaged in sexual activity a few days before the man’s symptoms began. The second case showed that the virus persisted in a man’s sperm even after it was undetectable in his blood. This man had no sexual partners. The third case is still under investigation.

According to the CDC, the men in all three cases developed symptoms of Zika infection. It is currently unknown whether men without symptoms can transmit the virus.

There have been no reports of women transmitting Zika to their partners.

According to the CDC, infection is asymptomatic in about 80 percent of Zika cases. When symptoms do occur, they are generally mild and brief.

However, the virus may carry the risk of birth defects — making it especially dangerous for pregnant women. New evidence suggests a possible link between Zika and microcephaly, as well as Guillain-Barré syndrome.

Microcephaly is a condition in which a baby’s brain does not develop normally, resulting in a smaller than average head. This may cause impaired cognitive development, delayed motor function and speech, among other problems.

Guillain-Barré syndrome is a condition in which the body's immune system attacks part of the peripheral nervous system. Neither disorder is curable.

To avoid these potentially severe conditions, the CDC urges men who live in or have traveled to Zika-infected areas, and also have pregnant partners, to either abstain from sexual activity or consistently use condoms. Couples should keep in mind that a person can have Zika and possibly transmit it without showing any symptoms.

The New York Times reports that, as of Feb. 2, health officials in Dallas, TX, have confirmed a single case of sexually-transmitted Zika.

The CDC currently does not recommend testing men to assess risk of sexual transmission.

Review Date: 
February 7, 2016
Last Updated:
February 9, 2016