In the most comprehensive study of COVID-19 pediatric patients to date, researchers provide critical data showing that children play a larger role in the community spread of COVID-19 than previously thought.
In a study of 192 children ages 0-22, 49 children tested positive for SARS-CoV-2, and an additional 18 children had late-onset, COVID-19-related illness. The infected children were shown to have a significantly higher level of virus in their airways than hospitalized adults in ICUs for COVID-19 treatment, according to Harvard-affiliated Massachusetts General Hospital (MGH) and Mass General Hospital for Children (MGHfC).
The study, Pediatric SARS-CoV-2: Clinical Presentation, Infectivity, and Immune Reponses, was published today 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, 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.
Transmissibility or risk of contagion is greater with a high viral load. And even when children exhibit symptoms typical of COVID-19, like fever, runny nose and cough, they often overlap with common childhood illnesses, including influenza and the common cold. This confounds an accurate diagnosis of COVID-19, the illness derived from the SARS-CoV-2 coronavirus, says Yonker. Along with viral load, researchers examined expression of the viral receptor and antibody response in healthy children, children with acute SARS-CoV-2 infection and a smaller number of children with Multisystem Inflammatory Syndrome in Children (MIS-C).
Findings from nose and throat swabs and blood samples from the MGHfC Pediatric COVID-19 Biorepository carry implications for the reopening of schools, daycare centers and other locations with a high density of children and close interaction with teachers and staff members.
Kids are not immune from this infection, and their symptoms dont correlate with exposure and infection, says Alessio Fasano, director of the Mucosal Immunology and Biology Research Center at MGH and senior author of the manuscript. 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. However, our results show that kids are not protected against this virus. We should not discount children as potential spreaders for this virus.
The researchers note that although children with COVID-19 are not as likely to become as seriously ill as adults, as asymptomatic carriers or carriers with few symptoms attending school, they can spread infection and bring the virus into their homes. This is a particular concern for families in certain socio-economic groups, which have been harder hit in the pandemic, and multi-generational families with vulnerable older adults in the same household. In the MGHfC study, 51 percent of children with acute SARS-CoV-2 infection came from low-income communities compared to 2 percent from high-income communities.
In another breakthrough finding from the study, the researchers challenge the current hypothesis that because children have lower numbers of immune receptors for SARS-CoV2, this makes them less likely to become infected or seriously ill. Data from the group show that although younger children have lower numbers of the virus receptor than older children and adults, this does not correlate with a decreased viral load. According to the authors, this finding suggests that children can carry a high viral load, meaning they are more contagious, regardless of their susceptibility to developing COVID-19 infection.
There is more to the article, but this is the bulk of it in terms of findings.
So healthy kids can have a higher level of the virus than adults in the ICU? That's scary. I mean it sounds like kids still aren't that at risk, but they have families.
