(CNN)The Zika virus causes microcephaly and other birth defects, the U.S. Centers for Disease Control and Prevention said Wednesday.
"This study marks a turning point in the Zika outbreak. It is now clear that the virus causes microcephaly," CDC director, Dr. Tom Frieden said.
Previously, the agency said it's likely the virus in pregnant women was the cause of the rare birth defect that results in an underdeveloped brain and that the evidence was mounting. However, they maintained that more research was needed before they could conclusively say it is causal.