Host immune responses to severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2), especially in children, are still under investigation.
Children with coronavirus disease 2019 (COVID-19) constitute a
significant study group of immune responses as they rarely present with
severe clinical manifestations, require hospitalization, or develop
complications such as multisystem inflammatory syndrome in children
(MIS-C) associated with SARS-CoV-2 infection. The deciphering of
children's immune responses during COVID-19 infection will provide
information about the protective mechanisms, while new potential targets
for future therapies are likely to be revealed. Despite the limited
immunological studies in children with COVID-19, this review compares
data between adults and children in terms of innate and adaptive
immunity to SARS-CoV-2, discusses the possible reasons why children are
mostly asymptomatic, and highlights unanswered or unclear immunological
issues. Current evidence suggests that the activity of innate immunity
seems to be crucial to the early phases of SARS-CoV-2 infection and
adaptive memory immunity is vital to prevent reinfection