The Zika virus may be more easily contracted through unprotected sex than originally believed, the Centers for Disease Control and Prevention said Tuesday.
The Atlanta-based agency issued the warning in a health alert citing 14 possible U.S. cases of the virus likely contracted through sex.
In three cases, the infected were women whose only known risk factor was sexual contact with men who’d recently traveled to regions with active outbreaks. Several of the women were pregnant. A CDC spokesman declined to say exactly how many of the pregnant women may have been affected or in what states those 14 people live.
Zika is linked to microcephaly, a birth defect that causes cognitive disorders and unusually small heads in newborns. It is also a suspect behind the increasing number of Guillain-Barre syndrome cases that have appeared in areas where Zika has flourished. Guillain-Barre is a virus that attacks the nervous system causing paralysis and, in some cases, death.
Since early last year Zika has spread across Latin and South America primarily through mosquito bites. Initially, it can be something of a stealth virus; four out of five people don’t get the telltale symptoms of Zika: conjunctivitis, joint pain, fever and rash. An infection is usually over in a week but the virus can persist in semen. Scientists haven’t figured out for how long.
For a pregnant woman, however, scientists suspect the virus can prove devastating to her fetus, which is why the CDC is reiterating its guidelines issued earlier this month regarding sexual contact. CDC researchers are racing to figure out exactly how Zika may affect a pregnancy and at what stage of a pregnancy a Zika infection is most dangerous. The agency now has a team in Brazil conducting a case-control study with women and children who have had the virus, and those who have not, to determine exactly how the virus might cause birth defects or if other factors may be at play.
In the meantime, the CDC is advising that pregnant women not have unprotected sex — vaginal, oral or anal — with any male partner who has returned from one of the regions. A couple should either use latex condoms or abstain from sex for the duration of the pregnancy, the agency said.
Until today, the CDC had only confirmed one U.S. case of Zika being sexually transmitted. In that instance, a Texas man who had recently returned from Venezuela, passed the virus to his female partner. While it wasn’t the first time Zika has been passed along sexually in the U.S., it was the first documented case during this current outbreak. The first known sexual transmission of the virus here was eight years ago in Colorado. A researcher who contracted the disease while working in Africa wound up passing the virus to his wife once he came home.
Georgia had its first case of travel-related Zika this month when an unidentified person returning from Colombia tested positive for exposure to the virus. State health officials are also waiting on test results from at least three other people who may have contracted the virus while traveling. Currently the CDC does all Zika testing for state and regional health departments at its facility in Colorado. In the coming weeks, however, the agency is expected to provide testing kits to some state health agencies, including Georgia's, so tests can be turned around faster. People who think they have been exposed to the virus would first have to be examined by their primary care physician who would then contact the Georgia Department of Public Health to arrange for testing.
U.S. health officials say the nation should expect the virus to spread here as mosquito season arrives. The Obama administration has asked Congress for $1.8 billion to prevent and fight the spread of disease which is proving difficult to contain.
