Does Primary 2-Dose COVID-19 Vaccination for Nursing Home Staff Prevent Resident Infections?

The high rate of COVID-19 infection, hospitalization, and death in nursing home residents led to a U.S. federal mandate for staff vaccination with the 2-dose primary series. This mandate took effect in early 2021 and has not been updated with booster requirements to account for new COVID-19 variants or declining immunity. In this study, researchers assessed the effectiveness of the mandate by linking national nursing home infection and staff vaccine data from 15,000 nursing homes. They compared the effectiveness of the primary 2-dose COVID-19 vaccine series during the initial Delta epidemic (May–December 2021) with the effectiveness of the same vaccine series during the Omicron wave (December 2021–January 2022).

During the Delta period, an i…