Children under the age of five have between 10 and 100 times higher levels of coronavirus genetic material in their noses compared to older children and adults, a study in JAMA Pediatrics said on Thursday.
Its authors write this implies that young children can be important drivers of COVID-19 transmission within communities – a suggestion contrary to the current narrative that prevails.
The paper comes as the administration of US President Donald Trump is putting great pressure on schools and day care to reopen in order to start the economy.
Between March 23 and April 27, researchers performed nasal swab tests on 145 Chicago patients with mild to moderate illness within a week of the onset of symptoms.
Patients were divided into three groups: 46 children younger than five years, 51children aged 5 to 17 years and 48 adults aged 18 to 65 years.
The team, led by Taylor Heald-Sargent of Ann & Robert H. Lurie Children’s Hospital, observed “a 10-fold to 100-fold increase in SARS-CoV-2 in the upper respiratory tract of young children “.
The authors added that a recent study in the laboratory had demonstrated that the more viral genetic material was present, the more infectious it could grow.
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 could potentially be significant drivers of SARS-CoV-2 prevalent in the general population,” the authors wrote.
“The behavioral habits of young children and nearby neighborhoods in school and day care settings raise concerns about SARS-CoV-2 amplification in this population as public health constraints have been eased,” they concluded.
The new findings contradict the current view among health authorities that young children – who, it has been well established, are much less likely to become seriously ill with the virus – do not spread them to others.
However, so far there has been quite a bit of research on this topic.
A recent study in South Korea found that children aged 10-19 transmitted COVID-19 within adult families, but children under nine transmitted the virus at lower rates.
© Agence France-Presse