- Emerging data consistently show that children are less likely to become infected with SARS-CoV-2
- Recent findings from England reveal that children accounted for only 1% of positive cases
- However, since there are still many unanswered questions about the virus, we need to remain vigilant
Children continue to account for the smallest percentage of Covid-19 infections. A new analysis, published in the Archives of Disease in Childhood, shows that during the first pandemic peak in England, children made up a low 1% of all positive SARS-CoV-2 (the virus that causes Covid-19) tests – this despite the fact that large numbers of people were tested.
The authors also wrote that the prevalence of the virus was low even in children with acute respiratory infections (ARI).
Children accounted for 1% of positive cases
The 14 researchers analysed cases between January and May 2020. Their paper states that a total of 540 305 people were tested for SARS-CoV-2, and 129 704 (24%) turned out to be positive.
The test results are from the UK National Health Service (NHS) and the Public Health England (PHE), as well as tests carried out by family doctors at 300 general practices contributing to the Royal College of General Practitioners' monitoring system for flu-like illness.
Of the 129 704 people who tested positive, children accounted for only 1 408 (1%) of cases.
Average ages of positive tests
The average age of children who tested positive was just under six years, while just over half (53%) of cases were boys. Infants, particularly those under three months, had the highest number of positive results.
In general practice, SARS-CoV-2 positivity was low, even in children with ARIs.
Nearly 3 000 people with respiratory illnesses were tested for the virus, and the percentages according to age of those testing positive were:
- 2.8% (10) children
- 9% between 15 and 44 years old
- 18.5% between 45 and 64
- 20.5% between 65 and 79
- 45.5% aged 80 and older
Death rate also low among children
According to the team, eight of the 1 408 children who tested positive for SARS-CoV-2 died, although only four died of Covid-19. They were between the ages of 10 and 15, and three of them had several co-existing conditions.
SARS-CoV-2 was confirmed as only an incidental or contributory factor in the other cases of childhood mortality.
"The experience in England adds to the growing body of evidence on the limited role of children in the Covid-19 pandemic, with just over 1% of confirmed cases occurring in children,” the authors wrote.
'We need to remain vigilant'
According to EurekAlert, lead author of the study and a researcher from Public Health England, Dr Shamez Ladhani said: “It is still not clear why young children have such a low risk of infection compared to older children and adults.
“One theory is that, compared to adults, children have fewer ACE2 receptors which the virus can bind to in cells that line the respiratory tract.
“The way the immune system reacts to the virus is also likely to be different in children compared to adults,” Ladhani commented.
ACE2 receptors (acting as "doors") allow the virus to enter the body’s cells. A previous Health24 article explains that studies have shown that children naturally present with fewer ACE2 receptors in their lungs than adults, while, according to the senior study author of one particular study, ACE2 receptors appear to increase with age.
Ladhani also commented that while these numbers are reassuring for children, one has to bear in mind that the tests were completed during lockdown where children were less likely to have been exposed to the virus.
"We need to remain vigilant as the lockdown eases and children have increased contact with other children and adults in the coming weeks. In particular, we need more information about asymptomatic infections and silent transmission," Ladhani cautioned.