Zika infection during pregnancy may cause deformities in babies’ limbs, experts have discovered, leading to predictions that many more Zika-linked conditions will be discovered.
Researchers from Recife, the Brazilian city at the centre of the epidemic spreading across the Americas, describe seven suspect cases of deformities in the prestigious British journal The BMJ.
Anthony Fauci, director of the US National Institute of Allergy and Infectious Diseases, said he was not surprised by the findings and believes many more related problems will be proven.
“As opposed to linking Zika just to microcephaly, there is a whole spectrum which they are now referring to as the [congenital] Zika syndrome, within which is included microcephaly but it is not limited to microcephaly,” he said.
“I can predict to you now that it is likely that the children who look reasonably normal, don’t have any gross formation defects, might later on have issues that relate to subtle things like visual defects, or hearing defects, or intellectual landmarks children get as they develop. So I think the syndrome is going to continue to broaden.”
Experts now agree Zika is capable of causing lasting brain damage to babies in the womb. The virus can cross the placenta from the mother to her unborn child. There is growing evidence that it can trigger a rare, weakening condition of the nerves, called Guillian-Barre syndrome, in adults.
Dr Vanessa van der Linden and her team in Brazil say seven babies with suspected Zika infection they studied had been born with hip, knee, ankle, elbow, wrist and/or finger joint problems that fit a medical diagnosis called arthrogryposis.
The deformities of arthrogryposis, or crooked joints, are caused by faulty muscles – some too tight or contracted and some too flaccid – that have pulled and held the baby’s growing body in unnatural positions.
The babies tested negative for other congenital pre-birth infections, such as rubella and HIV, that might have been a possible cause of their deformities. Most had microcephaly as well as the limb deformities.
Dr Linden says that since writing up her findings, she has seen 14 more babies with similar problems and is running more tests.
Professor Jimmy Whitworth, of the London School of Hygiene and Tropical Medicine, said studies suggest the current epidemic could go on for three or four years. “We think there’s going to be tens of thousands of babies who could be affected by Zika,” he said.
In the US, a Texas baby died from the virus yesterday. The baby’s mother had travelled to Latin America during her pregnancy. Four new cases were reported in Miami, the first place in North America where it is transmitted via local mosquitoes, bringing the total in that outbreak to at least 21 people.