REUTERS
One of the U.S.'s most senior public health officials has revealed the "strongest evidence to date" of the effect on babies of the Zika virus, according to the BBC.
Dr. Tom Frieden, head of the Center for Disease Control (CDC), was testifying before politicians in Washington, the BBC reports.
He said that data from the cases of two infants in Brazil who died soon after birth indicated the virus had passed from mother to child.
However, he said the suspected link was still not definite.
There are thought to have been more than 4,000 cases in Brazil alone of babies born with microcephaly – abnormally small brains – and where the transmission of Zika virus from mother to child is suspected of being the cause.
Dr. Frieden said intensive research was under way to find out much more about the mosquito-borne virus and to develop a vaccine for it, although he warned that that could still be years away.