학술논문

Effectiveness of BA.1- and BA.4/BA. 5-Containing Bivalent COVID-19 mRNA Vaccines Against Symptomatic SARS-CoV-2 Infection During the BA.5-Dominant Period in Japan
BRIEF REPORT
Document Type
Report
Source
Open Forum Infectious Diseases. June 2023, Vol. 10 Issue 6
Subject
Japan
Language
English
ISSN
2328-8957
Abstract
Although mRNA vaccines against coronavirus disease 2019 (COVID-19) initially showed high efficacy and effectiveness, waning immunity and the repeated emergence of variants with immune escape capacity caused concern [1]. To [...]
In this multicenter, prospective, test-negative, case-control study in Japan, the effectiveness of both BA.1-containing and BA.4/BA.5-containing bivalent coronavirus disease 2019 mRNA vaccines against symptomatic infection during the BA.5-dominant period was high compared with no vaccination (65% and 76%) and moderate compared with monovalent vaccines administered over half a year earlier (46% combined). Keywords. COVID-19; SARS-CoV-2; SARS-CoV-2 variants; test-negative design; vaccine effectiveness.