After several weeks of study and debate, US health officials have concluded that infection with the Zika virus during pregnancy causes the birth defect microcephaly, a finding that experts hope will refocus attention on efforts to stop infections and prompt US lawmakers to fund emergency prevention efforts.
"There isn't any doubt that Zika causes microcephaly," Dr Tom Frieden, director of the Centres for Disease Control and Prevention (CDC), told reporters yesterday.
US and world health officials have been saying for weeks that mounting scientific evidence points to the mosquito-borne virus as the likely cause of the alarming rise in microcephaly in Zika-hit areas of Brazil. It had not been declared as the definitive cause until now.
The announcement comes as the Obama Administration has been urging the Republican-controlled Congress to grant nearly US$1.9 billion ($2.8 billion) in emergency funds to fight the virus.