Immunogenicity of a BNT162b2 vaccine booster in health-care workers
Esther Saiag, Hanoch Goldshmidt, Eli Sprecher, Ronen Ben-Ami, David Bomze
Abstract
The Pfizer-BioNTech mRNA COVID19 vaccine (BNT162b2) was found to be highly efficacious against symptomatic SARS-CoV-2 infection, with a vaccine efficacy of 94% in a randomised clinical trial1 and an effectiveness of 94–95% in real-world studies in Israel.2 Similar effectiveness rates (97% against symptomatic infection and 86% against asymptomatic infection) were found in health-care workers.3 Waning vaccine effectiveness, concurrent with the spread of the delta (B.1.617.2) variant, prompted the Israeli Ministry of Health to recommend, in early August 2021, a booster dose for individuals aged 60 years or older who were administered a second dose of the vaccine at least 5 months earlier.