Abstract
BackgroundResidents of nursing homes experience disproportionate morbidity and mortality related to COVID-19 and were prioritized for vaccine introduction. We evaluated COVID-19 vaccine effectiveness (VE) in preventing SARS-CoV-2 infections among nursing home residents.MethodsWe used a retrospective cohort of 4,315 nursing home residents during December 14, 2020 - November 9, 2021. A Cox proportional hazards model was used to estimate hazard ratios comparing residents with a completed vaccination series to unvaccinated among those with and without prior SARS-CoV-2 infection (identified using positive SARS-CoV-2 tests and/or diagnosis codes), by vaccine product, and by period (before and during Delta variant predominance). VE was estimated as one minus the hazard ratio times 100%.ResultsOverall adjusted VE for the completed vaccination series was 58% (95%CI: 44%, 69%) among residents without a history of SARS-CoV-2 infection. During the pre-Delta period, the VE within 150 days of receipt of the second dose of Pfizer-BioNTech (67%, 95%CI: 40%, 82%) and Moderna (75%, 95%CI: 32%, 91%) was similar. During the Delta period, VE measured >150 days after the second dose was 33% (95%CI: -2%, 56%) for Pfizer-BioNTech and 77% (95%CI: 48%, 91%) for Moderna. Rates of infection were 78% lower (95%CI: 67%, 85%) among residents with prior SARS-CoV-2 infection and completed vaccination series compared to unvaccinated residents without a history of SARS-CoV-2 infection.ConclusionsCOVID-19 vaccines were effective in preventing SARS-CoV-2 infections among nursing home residents and history of prior SARS-CoV-2 infection provided additional protection. Maintaining high coverage of recommended doses of COVID-19 vaccines remains a critical tool for preventing infections in nursing homes.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have