Paris (AFP) – Doctors in France described what they said was the first confirmed case of a newborn infected in the womb with COVID-19 by the mother.
The baby, born in March, suffered from brain inflammation and COVID-19-related neurological symptoms in adults, but has since recovered, they reported Tuesday in the journal Nature Communications.
Previous research had pointed to the probable transmission of the virus from mother to fetus, but the study offers the first solid evidence, said lead author Daniele De Luca, a doctor at Antoine Beclere Hospital near Paris.
“We have shown that transmission from mother to fetus through the placenta is possible during the last weeks of pregnancy,” she said.
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Last week, researchers in Italy said data on 31 pregnant women hospitalized with COVID-19 “strongly suggested” that the virus could be transmitted to unborn babies.
A JAMA study in March that reported a similar number of pregnant patients with COVID-19 came to a similar conclusion.
But the evidence was still circumstantial.
“It is necessary to analyze maternal blood, amniotic fluid, newborn blood, the placenta, etc.,” De Luca said by phone.
“Obtaining all of these samples during a pandemic with emergencies everywhere has not been easy. That is why it was suspected but never proven.”
De Luca and his team gathered this data for the case of a pregnant woman in her twenties admitted to his hospital in early March.
Because the baby was delivered by caesarean section, all potential sources and reservoirs of the virus remained intact.
The researchers found that the concentration of SARS-CoV-2, the technical name given to the virus, was highest in the placenta.
“From there it passed through the umbilical cord to the baby, where it develops,” said De Luca. “That is the route of transmission.”
– ‘Bad news’ –
The baby began to develop severe symptoms 24 hours after birth, including severe body stiffness, white matter damage to the brain, and extreme irritability.
But before doctors could establish a course of treatment, symptoms began to subside. Within three weeks, the newborn had recovered almost entirely on its own.
Three months later, her mother has no symptoms.
“The bad news is that this really happened and can happen,” said De Luca. “The good news is that it is rare, very rare compared to the world population.”
Among the thousands of babies born to mothers with COVID-19, no more than one or two percent have tested positive for the virus, and fewer still show severe symptoms, said Marian Knight, professor of health for the maternal and child population at the Oxford University that was not involved in the research.
“The most important message for pregnant women remains to avoid infection by paying attention to hand washing and social distancing measures,” he said.
Others said the case study shed light on how the virus passes from mother to child.
“This report adds insight to a possible mechanism of transfer to the baby, through the placenta,” said Andrew Shennan, professor of obstetrics at King’s College London.
“But women can be sure that pregnancy is not a significant risk factor for them or their babies with COVID-19.”
