Alliance for Pandemic Preparedness
April 22, 2021
Effectiveness of the BNT162b2 Vaccine in Preventing COVID-19 in the Working Age Population – First Results from a Cohort Study in Southern Sweden
Category: Article Summary
Topic: Vaccines and Immunity
Keywords (Tags): vaccines
- [Pre-print, not peer-reviewed] The Pfizer-BioNTech vaccine was 86% effective in preventing infection >7 days after the second dose in a cohort study (n=806,000) in Sweden from December 2020 to February 2021. Effectiveness was only 42% >14 days after a single dose. The vaccinated population largely consisted of healthcare workers. SARS-CoV-2 incidence among unvaccinated individuals with a prior positive PCR test was considerably lower than among those without a prior positive test (28 vs. 294 cases per 100,000 person-weeks), suggesting that prior SARS-CoV-2 infection is 91% effective in preventing subsequent infection.
Bjork et al. (Apr 21, 2021). Effectiveness of the BNT162b2 Vaccine in Preventing COVID-19 in the Working Age Population – First Results from a Cohort Study in Southern Sweden. Pre-print downloaded Apr 22 from https://www.medrxiv.org/content/10.1101/2021.04.20.21254636v1