Rapid immune response in children protects them from Covid-19

Adults and children have differences in their 'innate immune systems' - Fundamental differences in the immune response of adults and children can help to explain why children are much less likely to become seriously ill from SARS-CoV-2, finds a new study by researchers at UCL and the Wellcome Sanger Institute. The study is the most comprehensive single-cell study to compare SARS-CoV-2 infection in adults and children across multiple organs. Researchers found that a stronger 'innate' immune response in the airways of children, characterised by the rapid deployment of interferons, helped to restrict viral replication early on. In adults, a less rapid immune response meant the virus was better able to invade other parts of the body where the infection was harder to control. As part of the Human Cell Atlas^* initiative to map every cell type in the human body, the findings will be a valuable contribution to predict personal risk from SARS-CoV-2. A nasal swab to measure the immune response in newly infected adults could be used to identify those at higher risk who may be candidates for pre-emptive monoclonal antibody treatment. Recent research has also suggested inhalation of interferons could be a viable therapy^**.