Study strengthens Zika link to brain condition
Scientists have found the Zika virus in the amniotic fluid of two pregnant women whose foetuses have been diagnosed with a congenital brain condition.
Earlier this month the World Health Organisation (WHO) said the link between microcephaly found in babies born to infected mothers should be considered a "public health emergency of international concern".
While the link has not yet been scientifically proven, the latest research suggests that the virus can cross the placental barrier.
So far 36 countries have been affected by the outbreak and WHO officials have predicted as many as four million people could be infected this year.
In 2015, the number of reported cases of babies with microcephaly in Brazil increased 20-fold when compared with previous years.
Babies born with microcephaly have abnormally small heads and are at risk of incomplete brain development.
The latest report, published in 'The Lancet Infectious Diseases' journal, details two cases of women from north-east Brazil who presented with symptoms of Zika infection during the first trimester of their pregnancies; ultrasounds confirmed the foetuses had microcephaly.
Samples of amniotic fluid, the protective liquid around the foetus, were analysed and scientists confirmed the presence of the virus.
Commenting on the report, Jimmy Whitworth, professor of international public health at the London School of Hygiene and Tropical Medicine, said: "This study does strengthen the body of evidence that Zika virus is the cause of foetal microcephaly in Brazil."
He added: "Importantly they did not find evidence of any other of the main infections known to cause microcephaly."