Children play a larger role in the community spread of COVID-19 than previously thought, according to a new pediatric study from Massachusetts General Hospital (MGH) and Mass General Hospital for Children (MGHfC).
Infected children have “a significantly higher level” of the virus in their airways than hospitalized adults in ICUs for COVID-19 treatment, according to a study, titled “Pediatric SARS-CoV-2: Clinical Presentation, Infectivity, and Immune Reponses,” published Aug. 19 in the Journal of Pediatrics.
“I was surprised by the high levels of virus we found in children of all ages, especially in the first two days of infection,” says Lael Yonker, MD, director of the MGH Cystic Fibrosis Center and lead author of the study. “I was not expecting the viral load to be so high. You think of a hospital, and of all of the precautions taken to treat severely ill adults, but the viral loads of these hospitalized patients are significantly lower than a ‘healthy child’ who is walking around with a high SARS-CoV-2 viral load.”
The study, claiming to be the most comprehensive of its kind to date, was funded by MCH, MGHfC, the National Institutes of Health, the Centers for Disease Control and Prevention, the Cystic Fibrosis Foundation and private donors and authored by 30 experts from MGHfC, MGH, Harvard Medical School, Massachusetts Institute of Technology, Brigham and Women’s Hospital and Harvard T.H. Chan School of Public Health.
For the study, researchers examined data on 192 children aging from newborn to 22 and found that 49 tested positive for SARS-CoV-2, the virus responsible for causing COVID-19—with an additional 18 showing late-onset of the COVID-19-related illness.
According to Yonker, risk of contagion for COVID-19 is greater with a high viral load, yet it is sometimes difficult for doctors to diagnose children with COVID-19, because many have common illnesses such as influenza and the common cold that overlap with it.
“Kids are not immune from this infection, and their symptoms don’t correlate with exposure and infection,” says Alessio Fasano, MD, director of the Mucosal Immunology and Biology Research Center at MGH and senior author on the study. “During this COVID-19 pandemic, we have mainly screened symptomatic subjects, so we have reached the erroneous conclusion that the vast majority of people infected are adults.”
Authors on the study hope the findings will help inform policy decisions around school openings, particularly when it comes to the impact on multigenerational families from lower economic groups. In the study, 51 percent of children with acute SARS-CoV-2 infection came from low-income communities compared to 2 percent from high-income communities.
Understanding MIS-C and post-infectious immune responses from pediatric COVID-19 patients is critical for developing next steps in treatment and prevention strategies, according to the researchers. Early insights into the immune dysfunction in MIS-C should prompt caution when developing vaccine strategies, Yonker says.
The study can be found here.