On Aug. 20, 2020, in the most comprehensive study of COVID-19 pediatric patients to date, Harvard Medical School researchers based at Massachusetts General Hospital and Mass General Hospital for Children provided data showing that children may play a larger role in the community spread of COVID-19 than previously thought. The study was published in The Journal of Pediatrics.

The researchers found that infected children carried high levels of the virus, or viral load, in their respiratory secretions, even children with mild or no symptoms. Age did not affect the ability to carry a high viral load, which is associated with increased risk of transmitting the virus to others.

Notably, the team found that infected children in the asymptomatic or early infection phase had significantly higher viral loads than hospitalized adults with severe COVID-19.

The results carry implications for the reopening of schools, daycare centers and other facilities with a high density of children and close interaction with teachers and staff members, the authors said. In addition, the team found that although younger children had lower levels of ACE2—the receptor protein that SARS-CoV-2 targets to enter human cells—than older children and adults, this did not correlate with decreased viral load.

This suggests that children can carry a high viral load regardless of their susceptibility to developing COVID-19 infection, according to the authors.