BNT162b2 mRNA COVID-19 Vaccine Effectiveness in the Prevention of SARS-CoV-2 Infection: A Preliminary Report

In the preregistration trial, data on efficacy of BNT162b2 mRNA vaccine against SARS-CoV-2 infection were not collected. This study aimed to evaluate vaccine effectiveness (VE) against documented infection. Bari Policlinico University Hospital health care workers (HCWs) who completed the vaccination schedule were matched with HCWs who had refused vaccination. VE for documented infection was 61.9% (95% confidence interval [CI], 19.2%-82.0%) 14-20 days after first dose, 87.9% (95% CI, 51.7%-97.0%) 21-27 days after first dose, and 96.0% (95% CI, 82.2%-99.1%) 7 or more days after second dose. Unvaccinated HCWs remain a concern in the context of the pandemic emergency.

Automated summary

The study evaluated the effectiveness of the BNT162b2 mRNA vaccine against documented infection among healthcare workers from Bari Policlinico University Hospital, showing high effectiveness levels after vaccination. Concerns remain about unvaccinated healthcare workers during the pandemic emergency.