Duration of protection of CoronaVac plus heterologous BNT162b2 booster in the Omicron period in Brazil.

ABSTRACT: To date, no information has been published on the effectiveness of inactivated whole-virus COVID-19 vaccines plus heterologous booster against symptomatic infection and severe outcomes (hospitalization or death) during the dominance of the SARS-CoV-2 Omicron variant period. We evaluated the vaccine effectiveness (VE) of CoronaVac plus BNT162b2 booster during the period of dominance of the Omicron variant in Brazil (January to April 2022). Using a test-negative design, we analysed data for 2,471,576 individuals tested during the Omicron variant's dominant period using a nationally linked database from Brazil. Compared to unvaccinated, vaccinees maintained protection against severe outcomes, with an estimated VE of 84.1% (95% CI:83.2-84.9) at more than 120 days after BNT162b2 booster. Furthe

SUBMITTER: Cerqueira-Silva T 

PROVIDER: S-EPMC9289933 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature