Elizabeth M. White, Ph.D., A.P.R.N., Xiaofei Yang, Sc.M., Carolyn Blackman, M.D., Richard A. Feifer, M.D., M.P.H., Stefan Gravenstein, M.D., M.P.H., Vincent Mor, Ph.D.
Introduction
Since the deployment of the messenger RNA (mRNA) vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)1,2 in nursing homes nationwide starting in mid-December 2020, aggregate public data have shown decreases in the incidence of cases of SARS-CoV-2 infection and related deaths.3 However, there have been minimal individual-level data available for understanding vaccine effectiveness in nursing home residents, who were absent from the clinical trials and who often have reduced immune responses.4 Using electronic health record data from Genesis HealthCare, a large long-term care provider in the United States, we report the incidence of SARS-CoV-2 infection among vaccinated residents and unvaccinated residents of 280 nursing homes across 21 states.