The Centers for Disease Control and Prevention (CDC) has issued new interim guidance on preventing the sexual transmission of Zika virus after confirming through laboratory testing, in collaboration with Dallas County Health and Human Services in Texas, the first case of Zika virus infection in a nontraveler in the continental U.S. during the current outbreak.
Although sexual transmission of Zika virus infection is possible, mosquito bites remain the primary way that Zika virus is transmitted, according to the CDC. Because no vaccine or treatment for Zika virus infections is available, the best way to avoid these infections is to prevent mosquito bites, the agency says.
To date, there have been no reports of sexual transmission of the Zika virus from infected women to their sex partners.
The CDC has issued the following updated recommendations for pregnant women, and for men with pregnant sex partners, who live in or have traveled to Zika-affected areas:
- Pregnant women and their male sex partners should discuss the male partner’s potential exposures and history of Zika-like illness with the pregnant woman’s health care provider. Providers should consult the CDC’s guidelines for evaluation and testing of pregnant women.
- Men with a pregnant sex partner who reside in or have traveled to an area of active Zika virus transmission and their pregnant sex partners should consistently and correctly use condoms during sex (vaginal, anal, or oral) or should abstain from sexual activity for the duration of the pregnancy. Consistent and correct use of latex condoms reduces the risk of sexual transmission of many infections, including those caused by other viruses, the CDC notes.
The CDC has also issued new recommendations for nonpregnant women, and men with nonpregnant sexual partners, who live in or have traveled to Zika-affected areas:
- Couples in which a man resides in or has traveled to an area of active Zika virus transmission who are concerned about sexual transmission of Zika virus may consider using condoms consistently and correctly during sex or abstaining from sexual activity.
- Couples may consider two key factors when making the decision to abstain from sex or to use condoms: 1) Zika virus illness is usually mild. An estimated 80% of infected people never have symptoms; when symptoms occur they may last from several days to one week. 2) The risk of Zika infection depends on how long and how much a person has been exposed to infected mosquitoes, and the steps taken to prevent mosquito bites while in an affected area.
New CDC recommendations for women who reside in areas with ongoing Zika virus transmission, both pregnant women and women of reproductive age, include the following:
- For pregnant women experiencing symptoms consistent with Zika virus disease, testing is recommended at the time of illness.
- For pregnant women not experiencing symptoms consistent with Zika virus disease, testing is recommended when women begin prenatal care. Follow-up testing around the middle of the second trimester of pregnancy is also recommended because of an ongoing risk of Zika virus exposure. Pregnant women should receive routine prenatal care, including an ultrasound during the second trimester of pregnancy. An additional ultrasound may be performed at the discretion of the health care provider.
- For women of reproductive age, health care providers should discuss strategies to prevent an unintended pregnancy, including counseling on family planning and the correct and consistent use of effective contraceptive methods, in the context of the potential risks of Zika virus transmission.
- Local health officials will need to determine when to implement testing recommendations for pregnant women without symptoms, based on information about local levels of Zika virus transmission and local laboratory capacity.
Source: CDC; February 5, 2016.