CDC officially links Zika virus to birth defect

CDC officially links Zika virus to birth defect

Scientists from the Centers for Disease Control and Prevention (CDC) said Wednesday that they have officially concluded that the Zika virus causes the serious birth defect known as microcephaly. 


Zika was previously believed to be linked to microcephaly, a birth defect that causes babies' heads to be too small, leading to developmental problems. But Wednesday’s release of a CDC study in the New England Journal of Medicine provides more conclusive evidence. 

“This study marks a turning point in the Zika outbreak,” CDC Director Tom Frieden said in a statement. “It is now clear that the virus causes microcephaly.”

Frieden said his agency is launching further studies to see if microcephaly is the “tip of the iceberg” of other brain problems that could be caused by Zika. 

The new findings come as the debate over funding from Congress to fight Zika intensifies. The White House has been putting pressure on Republican lawmakers to approve $1.9 billion in emergency funds for strategies like mosquito control and vaccine research. 

Republicans have largely resisted the push for new funds, though they signaled some new openness to the issue on Wednesday. 

The CDC said Zika increases the risk of the defect but does not guarantee that a baby will have microcephaly.

The CDC said it is not changing its current guidance, namely that pregnant women should avoid travel to areas in the Caribbean and South America where the virus is spreading, and that women in areas with active transmission take steps to avoid mosquito bites and engage in pregnancy planning. 

On Monday, as part of the push for new funding, CDC Deputy Director Anne Schuchat said that Zika is “a bit scarier than we initially thought.”

Schuchat said the virus is now believed to be linked to more complications in pregnancy, such as premature births, and she said the mosquitos that spread the virus are now believed to be in about 30 states, instead of 12. 

Zika is not believed to cause serious problems in people who are not pregnant and usually leads to mild symptoms. Officials say they are not expecting a widespread outbreak in the United States but cannot be sure, given uncertainty about the virus’s behavior.