2025 年 8 巻 2 号 p. 584-586
Although Japan recorded the world's highest rate of COVID-19 messenger ribonucleic acid (mRNA) vaccination doses per capita, COVID-19 cases and deaths exploded after the emergence of the Omicron variant, followed by a significant increase in excess deaths in 2022 and 2023. Although several hypotheses have been proposed to explain these phenomena, the truth remains to be established because sufficient studies and data disclosures have not been conducted to adequately investigate the possible contribution of mRNA vaccines. The causes of the excess deaths from not only COVID-19 but also other factors after repeated mRNA vaccinations must be elucidated, given this could provide valuable information to help combat future infectious disease outbreaks.
