Multisystem inflammatory syndrome in children (MIS-C), believed to be linked to COVID-19, damages the heart to such an extent that some children will need lifelong monitoring and interventions, said the senior author of a medical review. Case studies also show MIS-C can strike seemingly healthy children without warning three or four weeks after asymptomatic infections, said Alvaro Moreira, MD, MSc, of The University of Texas Health Science Center at San Antonio. Dr Moreira, a neonatologist, is an assistant professor of paediatrics in the university’s Joe R. and Teresa Lozano Long School of Medicine. The team reviewed 662 MIS-C cases reported worldwide between January 1 and July 25. Most of the 662 children suffered cardiac involvement as indicated by markers such as troponin, which is used with great accuracy in adults to diagnose heart attacks.