Protection by Vaccines and Previous Infection Against the Omicron Variant of Severe Acute Respiratory Syndrome Coronavirus 2.

ABSTRACT:

Background

The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evades immunity conferred by vaccines and previous infections.

Methods

We used a Cox proportional hazards model and a logistic regression on individual-level population-wide data from the Czech Republic to estimate risks of infection and hospitalization, including severe states.

Results

A recent (≤2 months) full vaccination reached vaccine effectiveness (VE) of 43% (95% confidence interval [CI], 42%-44%) against infection by Omicron compared to 73% (95% CI, 72%-74%) against Delta. A recent booster increased VE to 56% (95% CI, 55%-56%) against Omicron infection compared to 90% (95% CI, 90%-91%) for Delta. The VE against Omicron hospitalization of a recent full vaccination was

SUBMITTER: Smid M 

PROVIDER: S-EPMC9129207 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature