Children under the age of five have 10 to 100 times the level of coronavirus genetic material in their noses compared to older children and adults. JAMA Pediatrics said Thursday.
Its authors wrote that this meant that young children could be important drivers of COVID-19 transmission in communities – a proposal that contradicts the current story.
The document comes when the administration of US President Donald Trump insists on opening schools and kindergartens to accelerate the economy.
Between March 23 and April 27, the researchers performed nasal smear tests on 145 Chicago patients with mild to moderate illness within a week of symptoms.
Patients were divided into three groups: 46 children under the age of five, 51children between the ages of five and 17, and 48 adults between the ages of 18 and 65.
A team led by Taylor Hild-Sargent of Ann and Robert H. Lurie Children’s Hospital observed “10 to 100 times more SARS-CoV-2 in the upper respiratory tract of young children.”
The authors added that a recent laboratory study showed that the more viral genetic material, the more infectious virus can be grown.
It has also been previously shown that children with high viral loads of respiratory syncytial virus (RSV) are more likely to spread the disease.
“Thus, young children can potentially be important drivers of the spread of SARS-CoV-2 as a whole,” the authors wrote.
“The behavioral habits of young children and close members of schools and day care facilities are of concern about the increase in SARS-CoV-2 in this population, as health care constraints are reduced,” they conclude.
The new findings contradict the current public health view that young children – who have been found to be much less likely to develop the virus – do not spread it to others.
However, so far there is very little research on this topic.
A recent study in South Korea found that children between the ages of 10 and 19 transmitted COVID-19 in households as much as adults, but children under the age of nine transmitted the virus with lower rates.
© Agence France-Presse