Zika and Sexual Transmission

Basics of Zika Virus and Sex

Transmission

Zika can be passed through sex from a person who has Zika to his or her sex partners.
Sex includes vaginal, anal, oral sex, and the sharing of sex toys.
Zika can be passed through sex, even if the person does not have symptoms at the time.
- It can be passed from a person with Zika before their symptoms start, while they have symptoms, and after their symptoms end.
- Though not well documented, the virus may also be passed by a person who carries the virus but never develops symptoms.
Studies are underway to find out how long Zika stays in the semen and vaginal fluids of people who have Zika, and how long it can be passed to sex partners. We know that Zika can remain in semen longer than in other body fluids, including vaginal fluids, urine, and blood.

Prevention Basics

Condoms and other barriers* can reduce the chance of getting Zika from sex.
- Barriers that prevent passing Zika through sex include male and female condoms and dental dams.
- Dental dams are latex or polyurethane sheets used between the mouth and vagina or anus during oral sex.
To be effective, condoms should be used from start to finish, every time during vaginal, anal, and oral sex.
Not sharing sex toys can also reduce the risk of spreading Zika to sex partners.
Not having sex eliminates the risk of getting Zika from sex.

*For the purposes of this webpage, all barriers will be referred to as condoms.

What CDC is Doing

CDC and other public health partners continue to study Zika virus and how it is spread and will share new information as it becomes available. This continuing research may help us find out:

How common it is for Zika to be passed during sex by a man or woman.
If Zika can be passed through saliva during deep kissing.
If Zika passed to a pregnant woman during sex has a different risk for birth defects than Zika transmitted by a mosquito bite.

How to Prevent Sexual Transmission of Zika

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Others Concerned About the Sexual Transmission of Zika collapsed

Sexual Transmission and Testing

Pregnant women with possible sexual exposure to Zika should be tested for Zika infection.
CDC recommends Zika virus testing for people who may have been exposed to Zika through sex and who have Zika symptoms.
Testing blood, semen, vaginal fluids, or urine is not recommended to determine how likely a person is to pass Zika virus through sex. This is because there is still a lot we don’t know about the virus and how to interpret test results. Available tests may not accurately identify the presence of Zika or a person’s risk of passing it on through sex.
As we learn more and as tests improve, these tests may become more helpful for determining a person’s risk of passing Zika through sex.