A poor and delayed anti-SARS-CoV2 IgG response is associated to severe COVID-19 in children.

Background: Most children and youth develop mild or asymptomatic disease during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, a very small number of patients suffer severe Coronavirus induced disease 2019 (COVID-19). The reasons underlying these different outcomes remain unknown.

Blood neutrophils from children with COVID-19 exhibit both inflammatory and anti-inflammatory markers.

Background: Perhaps reflecting that children with COVID-19 rarely exhibit severe respiratory symptoms and often remain asymptomatic, little attention has been paid to explore the immune response in pediatric COVID-19. Here, we analyzed the phenotype and function of circulating neutrophils from children with COVID-19.

Methods: An observational study including 182 children with COVID-19, 21 children with multisystem inflammatory syndrome (MIS-C), and 40 healthy children was performed in Buenos Aires, Argentina.