A new review of pediatric clinical and basic science studies from around the world highlights the effects of COVID-19 in infants and children, including physiological impact, mental health, and growth and development. The article is published in the journal Physiology.
According to data provided by the U.S. Centers for Disease Control and Prevention, as of July 2021, less than 12% of severe cases of COVID-19—the disease caused by the SARS-CoV-2 virus—have occurred in children under the age of 18. Research has shown the reasons for this low number largely include distinctions in “developing” versus “developed” tissues and immune system differences in children versus adults, as well as variations in gene expression that contribute to the coronavirus’ spike protein’s ability to enter the body.
Although the disease in children mostly ranges from asymptomatic to mild symptoms, severe COVID-19—defined as requiring hospitalization and/or mechanical ventilation—can occur in some children as well as more long-term complications known as multisystem inflammatory syndrome in children (MIS-C). MIS-C presents approximately four to six weeks after initial infection in children 5 to 14 years of age with fever, elevation in inflammatory markers and severe multisystem organ involvement. A small percentage of children may also experience post-acute sequelae of SARS-CoV-2 infection weeks to months after the active infection has passed, also known as “long-haul COVID.”
COVID-19 not only affects children physically, but can also impact their growth and development, including delayed or impaired learning capacity and adaptive behavior. In addition, the reviewers suggest that children’s mental health may suffer as a result of the pandemic due to school closures, public places shutting down and physical distancing. These are important public health measures to reduce the spread of the disease, but can also increase the likelihood of physical problems. “Prolonged depression and anxiety may lead to negative impacts on the cardiovascular and neurological health of the child,” wrote the review authors. “On the positive side, the plasticity of a child’s physical and mental development, and the support the child receives from adults, including security and affection, can facilitate a return to normalcy.”
The reviewers explain that some of the research on COVID-19 in children has produced contradictory findings, which “underscores the complexity of COVID-19” and emphasizes the need for more study. “While clinical research is important in understanding the effects of COVID-19, basic science is also imperative in defining the biology of SARS-CoV-2 infection, the relationship between infection and immunological response, and [identifying] potential therapeutic targets,” the authors wrote.