Analyzing nasal swabs taken during the pandemic, researchers at Yale School of Medicine suggest that the frequent presence of other viruses and bacteria may have helped to protect children from the worst effects of COVID-19 by boosting their immune systems. Their results will be published July 1 in the Journal of Experimental Medicine ( JEM ). Children are generally more susceptible than adults to respiratory infections such as the common cold, and yet, for unknown reasons, the SARS-CoV-2 virus tends to cause less severe symptoms in children than in adults, resulting in lower rates of hospitalization and death during the COVID-19 pandemic.
The innate immune system provides the first line of defense against viruses and bacteria, quickly producing a variety of anti-viral and proinflammatory proteins to fend off infection while the body develops other, more targeted, immune responses such as antibodies. Studies have shown that, compared with adults, the innate immune system is more active in the nasal passages of children and might therefore be better at blocking the early stages of SARS-CoV-2 infection. But the reason for this increased activity is unknown.
Prior work suggested that heightened nasal innate immunity in children was due to intrinsic biological mechanisms inherent to their age. But we thought it could also be due to the high burden of respiratory viruses and bacterial infections in children." Ellen F.
Foxman, associate professor of Laboratory Medicine and Immunobi.
