IFNB1 and COVID-19: We report that patients with MIS-C at hospital admission had a significant increase of serum pro-inflammatory biomarkers including type II IFN (IFN-γ) but not type I IFNs (IFN-α and IFN-β), differently from acute SARS-CoV-2 infection where type I IFN responses appear as possibly more relevant, confirming the distinct immunopathological signature between acute COVID-19 and MIS-C (20).