Why Are Child Coronavirus Infections Less Severe?

Since coronavirus was declared a pandemic in early 2020 scientists have been perplexed about why children experience radically less severe symptoms that adults. New research from Yale University could help explain why COVID-19 discriminates against age, with scientists asserting immunological response to the infection is much more effective in children. For co-senior author of the paper Kevan Herold, the findings offer valuable insight into why COVID-19 outcomes are generally much worse in older patients.

Working with researchers from the Albert Einstein College of Medicine, Herold and his team analysed serum and cell samples taken from both adult and pediatric patients diagnosed with the virus and admitted to the Montefiore Medical Center in New York City. They observed significantly higher levels of certain immune system molecules in children, a discovery that could explain why symptoms are less severe in younger patients.

The role of serum cytokines

The findings were reported in the journal Science Translational Medicine, with Herold saying the presence of the immune system molecules could offer children stronger defense against COVID-19. “To our surprise, we found these particular serum cytokines were at higher levels in children than adults," says Herold, a C.N.H. Long Professor of Immunology and Internal Medicine at Yale. The team also noted certain antibody responses initially thought to be defensive were more pronounced in adults, suggesting they may not be as helpful as originally thought.

To compile data the team searched for noticeable variations in immunological responses to COVID-19. They found that levels of interleukin 17A (IL-17A), an immune system molecule that helps to mobilise defences during early infection, was were significantly higher in younger patients. Interferon gamma (INF-g), another immune system molecule that prevents viral replication, was also more pronounced.

Replicating the robust immunological response of children

Co-senior author of the study Betsy Herold says the study could be used to develop new immunological treatments for COVID-19, which has currently claimed the lives of more than 1.2 million people around the world. "The suggestion is that kids have a more robust, earlier innate immune response to the virus, which may protect them from progressing to severe pulmonary disease," says Herold said, a professor of paediatrics and microbiology-immunology at Albert Einstein College of Medicine.  

To find out more about the latest COVID-19 research being conducted in state-of-the-art laboratories around the world, don’t miss Solving Freeze Drying Bottlenecks For Diagnostics and Vaccines Production In The ‘New Normal’ with insight from Tim Lewis on behalf of Biopharma Group.