Cohort study of Covid-19 vaccine effectiveness among healthcare workers in Finland, December 2020 - October 2021.

ABSTRACT: Recently, Covid-19 vaccine effectiveness has decreased especially against mild disease due to emergence of the Delta variant and waning protection. In this register-based study among healthcare workers in Finland, the vaccine effectiveness of two-dose mRNA vaccine series against SARS-CoV-2 infection decreased from 82% (95% CI 79-85%) 14-90 days after vaccination to 53% (43-62%) after 6 months. Similar trend was observed for other series. Waning was not observed against Covid-19 hospitalization. These results facilitate decision-making of booster doses for healthcare workers.

SUBMITTER: Poukka E 

PROVIDER: S-EPMC8683266 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature