Objective: To investigate COVID-19 vaccine efficacy (VE) among healthcare workers (HCWs) in an ethnically diverse community healthcare system, during its initial immunization campaign. Methods: HCWs of the system were retrospectively included from the beginning of a COVID-19 vaccination program (December 16, 2020) until March 31, 2021. Those with a prior COVID-19 infection before December 15 were excluded. The Occupational Health department of the system ran a COVID-19 screening and testing referral program for workers, consistently throughout the study period. A master database had been established and updated comprising of the demographics, COVID-19 PCR assays, and vaccinations of each HCW. Andersen-Gill extension of the Cox models were built to estimate the VE of fully/partially vaccinated person-days at risk. Results: Among the 4317 eligible HCWs, 3249 (75%) received any vaccination during the study period. Vaccinated HCWs were older, less likely to be Black/African American, Hispanic/Latino or identify as two or more races, and more likely to be medical providers. After adjusting for age, sex, race, and the statewide background incidence at the time of vaccination, we observed a VE of 80.2% (95% CI: 57.5-90.8%) for [greater double equals]14 days after the first dose of Pfizer/Moderna, and 95.5% (95% CI: 88.2-98.3%) among those fully vaccinated (i.e. [greater double equals]14 days after the second dose of Pfizer/Moderna or the single dose of J&J/Janssen). Conclusion: COVID-19 vaccine effectiveness in the real world is promising, and these data in concert with culturally appropriate may decrease vaccine hesitancy.
COVID-19 Vaccine Efficacy in a Diverse Urban Healthcare Worker Population