Journal article
Effectiveness of a fourth dose of covid-19 mRNA vaccine against the omicron variant among long term care residents in Ontario, Canada: test negative design study
Abstract
OBJECTIVES: To estimate the marginal effectiveness of a fourth versus third dose and the vaccine effectiveness of mRNA covid-19 vaccines BNT162b2 and mRNA-1273 against any infection, symptomatic infection, and severe outcomes (hospital admission or death) related to the omicron variant.
DESIGN: Test negative design.
Authors
Grewal R; Kitchen SA; Nguyen L; Buchan SA; Wilson SE; Costa AP; Kwong JC
Journal
The BMJ, Vol. 378, ,
Publisher
BMJ
DOI
10.1136/bmj-2022-071502
ISSN
0959-8138