ATLANTA, April 13 (UPI) -- The Centers for Disease Control and Prevention said on Wednesday the Zika virus can cause birth defects like very small heads and other neurological damage in the fetuses of infected mothers.
CDC officials said they had gathered enough data to make the announcement, putting to rest questions about whether microcephaly was caused by Zika. The findings are also being published in the New England Journal of Medicine.
"There is no longer any doubt that Zika causes microcephaly," said C.D.C. director Dr. Thomas R. Frieden. He said "mounting evidence from many studies," pointed to "an unprecedented association."
"Never before in history has there been a situation where a bite from a mosquito can result in a devastating malformation," Frieden said.
Brazil has received the worst of the outbreak, with a spike in cases of microcephaly, a birth defect caused by an underdeveloped brain. It's most notable symptom is a noticeably small head.
There was wide debate about the actual effects of the Zika virus, at first thought to be harmless, but as months passed, Brazilian doctors began to notice a connection. It's the first time a mosquito-born virus has been found to cause birth defects.
Since the outbreak, studies have consistently found virus reaching a fetus's brain, destroying cells and halting brain growth. The damage can often kill the fetus, even late in pregnancies.
As the CDC, the National Institutes of Health, the World Health Organization, and other agencies have been raising public awareness about Zika, The virus continues to spread across Latin America and the Caribbean. Travelers have brought it into the southern United States too. Outbreaks have already happened in Puerto Rico, the U.S. Virgin Islands and Samoa.
Zika can be sexually transmitted as well, and doctors now recommend using a condom during or avoiding sexual intercourse completely with anyone who might be infected.