Pregnant women should be screened for Covid-19 after a new study showed there could be a nine per cent risk of the virus being passed on.
However all the positive cases were from babies born by caesarean but because of the strict measures already in place scientists believe the cases were all “maternal in origin”.
The study published in the journal JAMA Pediatrics looked at 33 babies whose mothers had the virus and found three, all boys, were born with it.
The births all took place at Wuhan Children’s Hospital in Wuhan – the epicentre of the outbreak.
Previous research has suggested developing foetus’ are safe from the potentially fatal bug – even if their mothers have it.
Corresponding author Professor Wenhao Zhou, of the Children’s Hospital of Fudan University, Shanghai, said: “Three of 33 infants, or nine percent, presented with early onset Covid-19 infection.
“Because strict infection control and prevention procedures were implemented during the delivery, it is likely the sources in the new borns’ upper respiratory tracts or anuses were maternal in origin.”
Two recent studies have found no evidence of the virus in babies born to affected mothers.
Samples of amniotic fluid that surrounds a growing foetus were clear of it – as well as cord blood and breast milk.
But direct transmission between a mother and unborn child “cannot be ruled out,” said Prof Zhou.
He added: “Therefore, it is crucial to screen pregnant women and implement strict infection control measures, quarantine of infected mothers, and close monitoring of new borns at risk of COVID-19.”
All three babies found to have the virus were delivered by caesarean section after their mothers developed pneumonia – one prematurely after just 31 weeks and 2 days.
This was due to the foetus being in distress and its mother contracting pneumonia brought on by Covid-19.
He required resuscitation but improved after two weeks on a ventilator. He also needed antibiotics and had suspected sepsis.
The others were born after about 40 weeks and had lethargy, fever and pneumonia. One was also vomiting. All three made full recoveries.
Prof Zhou said: “Consistent with previous studies, the clinical symptoms from 33 new borns with or at risk of COVID-19 were mild and outcomes were favourable.
“Of the three with symptomatic COVID-19, the most seriously ill may have been
symptomatic from prematurity, asphyxia, and sepsis, rather than COVID-19 infection.
He said as the pandemic spreads rapidly across the world, the number of pregnant women and children with COVID-19 is also on the rise.
Prof Zhou said: “However, only 19 babies born to affected mothers have been investigated, and to our knowledge, no information on early-onset infection in newborns has been published in previous studies.”
His analysis had to be approved by the local medical ethics committee, with written informed consent obtained from the new borns’ parents.
The data was collected from January 2020 to February 2020.
At least two new born babies have tested positive for Covid-19 in the UK – one in Norfolk and the other in north London.
It is not known if they were infected in the womb or during or after birth.