Antibody responses and SARS-CoV-2 infection after BNT162b2 mRNA booster vaccination among healthcare workers in Japan.

Introduction: Vaccine effectiveness against SARS-CoV-2 infections decreases due to waning immunity, and booster vaccination was therefore introduced. We estimated the anti-spike antibody (AS-ab) recovery by booster vaccination and analyzed the risk factors for SARS-CoV-2 infections.

Methods: The subjects were health care workers (HCWs) in a Chiba University Hospital vaccination cohort.

Adverse effect investigation using application software after vaccination against SARS-CoV-2 for healthcare workers.

Introduction: The usefulness of smartphone-based application software as a way to manage adverse events (AEs) after vaccination is well known. The purpose of this study is to clarify the usefulness and precautions of employing a smartphone application for collecting AEs after the administration of Comirnaty®️.

Methods: Healthcare workers (HCWs) who were vaccinated with Comirnaty®️ were asked to register for the application software and to report AEs for 14 days after vaccination.