DALLAS (AP) — A person in Texas has been infected with the Zika virus after having sex with an ill person who had returned from South America, Dallas County health officials said Tuesday.
It’s the first case of the virus being transmitted in the U.S. during the current outbreak of Zika, which has been linked to birth defects in the Americas.
“It’s very rare but this is not new, we always looked at the point that this could be transmitted sexually,” said Zachary Thompson, director of the Dallas County Health and Human Services, told WFAA-TV in Dallas.
Health officials did not release any details about the Texas patient, citing privacy issues. In a tweet, Dallas health officials said the first person infected had been to Venezuela, but did not detail when and where that person or the second person was diagnosed. The second person did not travel.
The Zika virus is usually spread through mosquito bites, but investigators have been exploring the possibility the virus also can be spread through sex. There was report of a Colorado researcher who picked up the virus in Africa and apparently spread it to his wife back home in 2008, and it was found in one man’s semen in Tahiti.
“That gives you the plausibility of spread, but the science is clear to date that Zika virus is primarily transmitted to people through the bite of an infected mosquito,” Dr. Anne Schuchat of the Centers for Disease Control said during a recent news conference.
The CDC says it will issue guidance in the coming days on prevention of sexual transmission of Zika virus, focusing on the male sexual partners of women who are or may be pregnant. The CDC has already recommended that pregnant women postpone trips to more than two dozen countries with Zika outbreaks, mostly in Latin America and the Caribbean, including Venezuela. It also said other visitors should use insect repellent and take other precautions to prevent mosquito bites.
In the epidemic in Latin America and the Caribbean, the main villain identified so far is called Aedes aegypti — a species of mosquito that spreads other tropical diseases, including chikungunya and dengue fever. It is found in the southern United States, though no mosquito-borne transmission has been reported in the continental United States to date.
The World Health Organization on Monday declared a global emergency over the rapidly spreading Zika virus, saying it is an “extraordinary event” that poses a threat to the rest of the world. The declaration was made after an emergency meeting of independent experts called in response to a spike in babies born with brain defects and abnormally small heads in Brazil since the virus was first found there last year.
WHO officials say it could be six to nine months before science proves or disproves any connection between the virus and babies born with abnormally small heads.
The CDC said that in the recent Texas case, there’s no risk to a developing fetus.
Zika was first identified in 1947 in Uganda. It wasn’t believed to cause any serious effects until last year; about 80 percent of infected people never experience symptoms.
The most common symptoms are fever, rash, joint pain and red eyes. The illness is usually mild with symptoms lasting several days to a week. Symptoms usually start two days to a week after being bitten by an infected mosquito.
While Thompson told the television station that the case of sexual transmission is “a game-changer,” he added that he didn’t want people in Dallas County to overreact. Health officials and Thompson noted that sexual partners can protect themselves by using condoms to prevent spreading sexually transmitted infections.
Associated Press writer Mike Stobbe in New York contributed to this report.