Among health care workers, a fourth dose vaccine effectiveness against any SARS-CoV-2 Omicron variant infection was 30% for the Pfizer–BioNTech and 11% for the Moderna.
17 Mar, 2022 | 09:12h | UTCEfficacy of a Fourth Dose of Covid-19 mRNA Vaccine against Omicron – New England Journal of Medicine
Related: [Preprint] Fourth dose of COVID vaccine offers only slight boost against Omicron infection.