Pfizer-BioNTech and Moderna COVID-19 vaccines are highly effective under real-world setting in preventing symptomatic COVID-19 illness among healthcare personnel, including healthcare personnel at risk for severe COVID-19 and among racial/ethnic groups disproportionately affected by the pandemic. Initial results of PREVENT I demonstrating the real world effectiveness of both mRNA COVID-19 vaccines were published before the Delta variant became widespread.
The investigator teams at UCLA, Olive View-UCLA, and University of Iowa will continue surveillance of health care personnel (HCP) in Project PREVENT II. Objectives of PREVENT II are to evaluate SARS-CoV-2 vaccine effectiveness in preventing laboratory-confirmed symptomatic COVID-19 among HCP, specifically focusing on the effect of vaccine boosters and temporal changes in vaccine effectiveness.
