US health officials have said there is now enough evidence to say the Zika virus can cause unusually small heads and brain damage in babies.
The Centres for Disease Control and Prevention (CDC) said there was an established link between pregnant women catching Zika and their babies developing microcephaly as well as other neurological abnormalities.
Dr Thomas Frieden, from the CDC, said: “There is no longer any doubt that Zika causes microcephaly.
“Never before in history has there been a situation where a bite from a mosquito can result in a devastating malformation.”
It comes as experts in Brazil said they had found evidence of “extremely severe” brain damage in babies.