Effectiveness of the BNT162b2 Covid-19 Vaccine against the B.1.1.7 and B.1.351 Variants
Analysis of data from Qatar estimates the Pfizer BioNTech Covid-19 vaccine had 89.5% (95% CI 85.9-92.3) effectiveness against documented infection with the B.1.1.7 variant and 75.0% (70.5-78.9) effectiveness against infection with the B.1.351 variant ≥14 days after the 2nd dose.
Source:
New England Journal of Medicine
SPS commentary:
This research is described in a letter to the editor. Vaccine effectiveness against severe, critical, or fatal disease due to infection with any SARS-CoV-2 (with the B.1.1.7 and B.1.351 variants being predominant within Qatar) was 97.4% (95% CI 92.2 to 99.5). Vaccine effectiveness was estimated with a test-negative case–control study design.
Vaccine effectiveness was also assessed with the use of a cohort study design by comparing the incidence of infection among vaccinated persons with the incidence in the national cohort of persons who were antibody-negative. Using this method, effectiveness was estimated to be 87.0% (95% CI 81.8 to 90.7) against the B.1.1.7 variant and 72.1% (66.4 to 76.8) against the B.1.351 variant.