Federal scientists are investigating 14 reports of possible sexual transmission of the Zika virus, a reminder that mosquito bites aren’t the only way the virus can spread.
The Centers for Disease Control and Prevention is examining the 14 reports, several of which involve pregnant women, the agency said.
The virus was confirmed in two women who had sex with ill men who recently traveled to Zika-affected countries, CDC said.
The agency has run lab tests for four women but confirmation is needed. The agency also is investigating another eight cases.
“In all events for which information is available, travelers were men and reported symptom onset was within two weeks before the non-traveling female partner’s symptoms began,” the CDC notice said.
Zika is primarily spread through mosquito bites. It causes a mild illness, but the CDC strongly suspects it also causes a birth defect called microcephaly that causes babies to have abnormally small heads.
There have been more than 80 reported cases of Zika in the U.S., but almost all have been travelers who got infected in an area where the virus is spreading and then returned to the U.S.
Zika is spreading in more than 30 countries, primarily in central and South America.
The virus has spread only sexually in the U.S. It has not spread through mosquitoes.
The first confirmed case was a Texas woman who had sex with a man who recently returned to the country.
The case prompted the CDC to issue guidelines that called for pregnant women to refrain from sex or to use a condom if the man lives in or recently traveled to a Zika-affected country.
Zika can last in the blood stream for about two weeks, but scientists have no idea how long it can last in semen.
“The science is not clear on how long the risk should be avoided,” CDC said. “Research is now underway to answer this question as soon as possible.”
