Effects of Previous Infection and Vaccination on Symptomatic Omicron Infections.

ABSTRACT:

Background

The protection conferred by natural immunity, vaccination, and both against symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with the BA.1 or BA.2 sublineages of the omicron (B.1.1.529) variant is unclear.

Methods

We conducted a national, matched, test-negative, case-control study in Qatar from December 23, 2021, through February 21, 2022, to evaluate the effectiveness of vaccination with BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna), natural immunity due to previous infection with variants other than omicron, and hybrid immunity (previous infection and vaccination) against symptomatic omicron infection and against severe, critical, or fatal coronavirus disease 2019 (Covid-19).

Results

The effectiveness of previous infe

SUBMITTER: Altarawneh HN 

PROVIDER: S-EPMC9258753 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature