Postvaccination SARS-CoV-2 infection among healthcare workers – A Systematic Review and meta-analysis

ABSTRACT INTRODUCTION Healthcare workers (HCWs) remain on the front line of the battle against SARS-CoV-2 and COVID-19 infection, and are among the highest groups at risk of infection during this raging pandemic. We conducted a systematic review and meta-analysis to assess incidence of postvaccination SARS-CoV-2 infection among vaccinated HCWs. METHODS We searched multiple databases from inception through August 2021 to identify studies that reported on incidence of postvaccination SARS-CoV-2 infection among HCWs. Meta-analysis was performed to determine pooled proportions of COVID-19 infection in partially and fully vaccinated individuals. RESULTS Eighteen studies with 228,873 HCWs were included in the final analysis. Total number of partially vaccinated, fully vaccinated, and unvaccinated HCWs were 132,922, 155,673 and 17505, respectively. Overall pooled proportion of COVID-19 infections among partially/fully vaccinated and unvaccinated HCWs was 2.1% (95% CI 1.2-3.5). Among partially vaccinated, fully vaccinated and unvaccinated HCWs, pooled proportion of COVID-19 infections was 3.7% (95% CI 1.8-7.3), 1.3% (95% CI 0.6-2.9), and 10.1% (95% CI 4.5-19.5), respectively. DISCUSSION Our analysis shows the risk of COVID-19 infection in both partially and fully vaccinated HCWs remains exceedingly low when compared to unvaccinated individuals. There remains an urgent need for all frontline HCWs to be vaccinated against SARS-CoV-2 infection.