COVID-19 Vaccines: Myocarditis Reports Could Slow Expansion Into Pediatric Age Groups

An imbalance in myocarditis reports following mRNA vaccination could complicate expansion of the Pfizer Inc./BioNTech SE and Moderna, Inc. COVID-19 vaccines into younger age groups in the US.

Concerns about cases of myocarditis, inflammation of the heart muscle, occurring in older male adolescents and young men shortly after the second dose hung like a cloud over a Food and Drug Administration advisory committee's discussions about pediatric safety data requirements for emergency use authorization and licensure of COVID-19 vaccines