What is Known: • Long COVID is characterized by persistent symptoms following COVID-19, which can affect various tissues and organs, as well as mental health. • Due to the similar course of COVID-19 — mainly mild or asymptomatic — among children with and without immunodeficiency, the question arises, over whether the prevalence and severity of long-COVID is also similar in both groups.

What is New: • Immunocompromised children also suffer from long-COVID, but the prevalence is significantly lower than in the immunocompetent group of children. • The potential causes of less frequent and milder long-COVID in this group may be the milder course of COVID-19 and the state of reduced immunity protecting against neuroinflammation.