The U.S. Centers for Disease Control and Prevention (CDC) on Friday reported six confirmed and probable cases of sexual transmission of the mosquito-borne Zika virus from male travelers to female non-travelers.
The findings suggest that sexual transmission of the virus might be more common than previously reported, the CDC said.
U.S. health officials on Tuesday said it was investigating 14 reports of the Zika virus that may have been transmitted through sex, including to several pregnant women.
In two of the suspected cases, the infection had been confirmed in women whose only known risk factor was sexual contact with an infected male partner who had recently traveled to an area with active Zika transmission through mosquito bites, the CDC said on Tuesday.
The agency said on Friday that of the nine cases of U.S. pregnant travelers infected with Zika, one delivered a child with birth defects.
Pregnancy outcomes among the nine confirmed cases included two early pregnancy losses, two elective terminations, and three live births.
Two pregnancies are continuing without known complications, the agency said.