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

• DOI: 10.1007/s40264-021-01104-9
• Publication Date: 2021-08-04T14:03:01Z
• Authors: Toyotaka Iguchi; Hikari Umeda; Michie Kojima; Yuri Kanno; Yuta Tanaka; Natsumi Kinoshita; Daisaku Sato
• Keywords: 2019-20 coronavirus outbreak

In mid-February, the nationwide immunization plan for 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 phase-in period from February to March, attention was post-vaccination anaphylaxis and anaphylactoid symptoms viewpoint ensuring safety vaccination program.The aim this report provide update status occurring after COVID-19, as reported under Adverse Event Following Immunization (AEFI) reporting system Japan.The Pharmaceutical Medical Devices Agency (PMDA) received AEFI reports professionals manufacturers which has been operation since mid-February 2021. Reported AEFIs were assessed Brighton Collaboration Criteria assess diagnostic certainty.1-month program COVID-19 2021, 578,835 doses have administered professionals, with PMDA receiving 181 suspected event symptoms. 171 these cases, women developed Among cases evaluated according Criteria, 47 (26%) classified level 1-3 (reporting rate: 8.1/100,000 doses).The results appear similar foreign studies administration although rate higher. Further work is needed examine causal relationship reactions administration. Issues multiple possible sex/age bias also remain be analyzed.