Effectiveness of #BNT162b2 and #mRNA-1273 #JN1-adapted #vaccines against #COVID19-associated #hospitalisation and #death ...
Summary Background Little epidemiological evidence exists on the protective effects of the JN.1 -adapted mRNA vaccines against COVD-19 hospitalisation and death. In this study, we estimated vaccine effectiveness against COVID-19 hospitalisation and death. Methods This nationwide, register-based, cohort study included all Danish residents older than 65 years on Oct 1, 2024 . We used Denmark's national COVID-19 surveillance system and comprehensive population-based registers, which are updated daily and linked via the unique civil registration number assigned to all residents. To minimise differences between the comparison groups with regard to vaccination history, participants were required to have completed a primary vaccination course in 2021 and have received the 2023–24 XBB.1.5-adapted vaccine between Oct 1, 2023, and Jan 15, 2024. Participants with a recent recorded infection, or a vaccine dose since the previous season and prior to study start, were excluded. COVID-19 hospital...