The Centers for Disease Control has definitively linked the virus to birth defects.  

By Brigitt Earley
Updated April 14, 2016
Grant Cornett

On Wednesday, amid growing concern over the negative effects of Zika, the Centers for Disease Control (CDC) concluded that the virus does cause birth defects.

Since news of an outbreak in Brazil, the virus has been linked to a number of afflictions, namely microcephaly (a birth defect that causes unusually small heads in infants), Guillian-Barre Syndrome (a rare condition that attacks the nervous system), and acute disseminated encephalomyelitis (an autoimmune disease similar to multiple sclerosis). The CDC statement settles any doubt that the mosquito-borne virus does, in fact, cause microcephaly. More research will be needed before definitive conclusions can be made about the neurological dangers.

"It is now clear that the virus causes microcephaly. We are also launching further studies to determine whether children who have microcephaly born to mothers infected by the Zika virus is the tip of the iceberg of what we could see in damaging effects on the brain and other developmental problems,” Tom Frieden, M.D., M.P.H., director of the CDC, said in a statement. “We've now confirmed what mounting evidence has suggested, affirming our early guidance to pregnant women and their partners to take steps to avoid Zika infection and to health care professionals who are talking to patients every day. We are working to do everything possible to protect the American public."

Though pregnant women who contract Zika have a heightened risk of delivering a baby with birth defects, not all women who contract the virus while pregnant will have babies with microcephaly or other problems. Still, health officials warn expectant mothers and their partners to avoid travel to affected areas, follow strict steps to avoid mosquito bites, and talk to doctors about avoiding additional risk.