Effectiveness and waning of the fourth dose mRNA COVID-19 vaccines for the prevention of SARS-CoV2 infection related hospitalisations and deaths.
BACKGROUND Real-world data studies suggest that the vaccine effectiveness (VE) of a fourth mRNA vaccine dose against SARS-CoV2 infection related hospitalisation wanes after a few months, potentially warranting consideration of additional booster doses. METHODS A multi-database cohort study was conducted through the D...