Organization (WHO) received reports of 1,010 probable cases of severe acute hepatitis of unknown etiology (SAHUE) in young children from 35 countries (1). Many cases resulted in severe clinical outcomes; ≈5% of patients required liver transplants, and 22 died. Most (48%) cases were reported from the WHO European Region, and 484 cases were reported in previously healthy children from 21 countries (1). Ireland reported 28 probable cases of SAHUE in non-A-E hepatitis, including 2 patients who received liver transplants and 1 who died but did not receive a transplant (2).The causes of SAHUE remain unclear. A possible connection with SARS-CoV-2 has been suggested (3), but SARS-CoV-2 RNA was detected in only 16% of SAHUE cases reported in the WHO European Region (1). Recent studies suggest a possible association between SAHUE and human adenovirus (HAdV) species F type 41 (HAdV-F41) and adeno-associated virus 2 (AAV2) infections (4,5; A. Ho et al., unpub. data,