Effectiveness and Duration of Protection of a Fourth Dose of Coronavirus Disease 2019 Messenger RNA Vaccine Among Long-term Care Residents in Ontario, Canada
Ramandip Grewal, Lena Nguyen, Sarah A. Buchan, Sarah E. Wilson, Andrew P. Costa, Jeffrey C. Kwong
Abstract
We estimated the effectiveness of a fourth dose of messenger RNA coronavirus disease 2019 vaccine against Omicron infections and severe outcomes over time among long-term care residents in Ontario, Canada. Fourth doses provide additional protection against Omicron-related outcomes, but the protection wanes over time, with more waning seen against infection than severe outcomes.
Topics & Concepts
Coronavirus disease 2019 (COVID-19)Duration (music)VirologySevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2)2019-20 coronavirus outbreakCoronavirusMedicineTerm (time)DiseaseOutbreakInfectious disease (medical specialty)Internal medicineLiteratureQuantum mechanicsArtPhysicsSARS-CoV-2 and COVID-19 ResearchVaccine Coverage and HesitancyCOVID-19 epidemiological studies