Pfizer-BioNTech vaccine booster reduces mortality due to COVID-19 by 90%

Reference

Arbel R, Hammerman A, Sergienko R, et al. BNT162b2 vaccine booster and mortality due to covid-19. N Engl J Med 2021;385(26):2413-2420.

Synopsis

In response to the rising number of cases of the delta variant of COVID-19 and the reduced vaccine efficacy over time, on July 30, 2021, the Israeli Ministry of Health recommended a third dose of the Pfizer/BioNTech vaccine for persons 50 years and older who had received their second dose at least 5 months earlier. (This study predates the omicron wave.) This observational study of 843,208 persons compared the outcomes in persons who received a third dose (booster) and those who were vaccinated but did not receive the booster. Persons with a previous COVID-19 infection and those who had a confirmed case before the booster had time to become effective were excluded. Persons who chose to receive a booster were, on average, older (69 vs 65 years), more likely to be Jewish (89% vs 68%), and had a higher socioeconomic status than those who did not; there were no clinically significant differences between groups with regard to comorbidities. The authors adjusted the analysis for the socioeconomic and demographic differences. The primary outcome of death due to COVID-19 occurred much less often in the boosted group (0.16 vs 2.98 deaths per 100,000 persons per day; adjusted hazard ratio 0.10; 95% CI 0.07 - 0.14). It is possible that those seeking a booster were also more likely to engage in other protective health behaviors.