Cumulative Adverse Event Reporting of Anaphylaxis After mRNA COVID-19 Vaccine (Pfizer-BioNTech) Injections in Japan: The First-Month Report

In mid-February, the nationwide immunization plan for the prevention of coronavirus disease 2019 (COVID-19) started in Japan (at first primarily focused on health professionals) using an mRNA-based vaccine (Pfizer/BioNTech). During the phase-in period from February to March, attention was focused on post-vaccination anaphylaxis and anaphylactoid symptoms from the viewpoint of ensuring the safety of the vaccination program.The aim of this report...