The incidence, clinical characteristics, and severity of outcomes of COVID-19 in children differ from those seen in adults. Questions remain regarding whether these differences are due to decreased susceptibility or testing and whether infected children can infect others. Findings from a recent study suggest that children are less likely to develop and spread COVID-19.

The authors of the study collected data from 637 households in which all members (3,353 total) had been tested for COVID-19 using polymerase chain reaction (PCR), a type of diagnostic test. A subset of 714 household members underwent serological testing for the presence of antibodies to the SARS-CoV-2 virus, the virus that causes COVID-19. They analyzed the data using mathematical modeling.

The PCR data indicated that nearly half (1,510) of the household members tested positive for COVID-19, but children (defined as 20 years and younger) were half as likely to test positive compared to adults. Interestingly, the serological data revealed that PCR testing under-detected infections in children. The mathematical modeling data indicated that children were 43 percent less likely than adults to be infected with SARS-CoV-2. If infected, they were 63 percent less likely than adults to spread the infection.

These findings suggest that low susceptibility and under-detection of positive cases in children contribute to the low number of COVID-19 cases in children. The authors of the study posited that their model could have application in other settings, such as nursing homes and schools, to help understand disease transmission and guide public health policy.

• Link to full study.