Comparative effectiveness of heterologous third dose vaccine schedules against severe covid-19 during omicron predominance in Nordic countries: population based cohort analyses.

ABSTRACT:

Objective

To investigate the comparative vaccine effectiveness of heterologous booster schedules (ie, three vaccine doses) compared with primary schedules (two vaccine doses) and with homologous mRNA vaccine booster schedules (three vaccine doses) during a period of omicron predominance.

Design

Population based cohort analyses.

Setting

Denmark, Finland, Norway, and Sweden, 27 December 2020 to 31 December 2022.

Participants

All adults aged ≥18 years who had received at least a primary vaccination schedule of AZD1222 (Oxford-AstraZeneca) or monovalent SARS-CoV-2 wild type (ancestral) strain based mRNA vaccines BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna), in any combination.

Main outcome measures

The main outcome measure was country combined risks of

SUBMITTER: Andersson NW 

PROVIDER: S-EPMC10360027 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature