One in 10 U.S. women with Zika had deformed fetus or baby
The study released by the U.S. Centers for Disease Control and Prevention (CDC) tracked 250 pregnant women who had confirmed Zika infection in 2016.
Twenty-four of these women either had a fetus or baby with defects, said the CDC Vital Signs report, the first research of its kind to be released since the mosquito-borne virus made its way into the United States last year.
Zika can cause brain defects such as microcephaly, an irreversible condition in which the child's brain and skull are unusually small and misshapen.
But even though some babies are born without any outward signs of defects, they may go on to show developmental delays, so researchers cautioned that their estimates may be lower than reality.
Since Zika erupted on a large scale in mid-2015, more than 1.5 million people have been infected, mostly in Brazil and other countries in South America. Some 70 countries have been impacted.
Zika may lead to an itchy rash but often causes no symptoms.
Its effects on the fetus were particularly acute when the virus attacked a woman in the first trimester of pregnancy.
"Confirmed infections in the first trimester posed the highest risk—with about 15 percent having Zika-related birth defects," said the CDC Vital Signs report.
Most of the cases involved women who acquired the virus while traveling outside the country.
Local cases of Zika have been reported in Florida and Texas, and the virus can also be transmitted through sex. ■