Clinical course of COVID-19 in children with pre-existing medical conditions.

Children appear to have milder COVID-19 than adults and a more favourable clinical course (1-2). Adult comorbidities, including advanced age, diabetes and cardiovascular disease, have been associated with severe COVID-19 and the highest mortality rates (3). We presume that children with pre-existing conditions face a higher risk from COVID-19 than healthy peers, but studies are scarce and detailed clinical information has often been lacking. Bixler et al studied 121 people under 21 years, whose deaths were associated with COVID-19 and had been reported to the American Centers for Disease Control by 31 July 2020. They found that 75% had at least one underlying medical condition (4) and the most frequent were chronic lung disease, including asthma, and neurological, developmental and cardiovascular conditions. A systematic review by Williams et al reported that paediatric comorbidities increased the risk of critical COVID-19 and cardiac disease was the most common comorbidity (5).