SARS-CoV-2 outbreaks in long-term care facilities during the Omicron era in Québec, Canada.

Residents of long-term care facilities (LTCFs) are at a high risk of severe COVID-19. Our study analyzed the COVID-19 outbreaks, associated cases and case fatality ratio (CFR) in LTCFs from May-2022 to September-2024 in Québec, Canada. An ecological analysis was conducted including all active LTCFs during the study period (n = 471). Regression analyses using generalized estimating equations were used to model odds of an active COVID-19 outbreak, confirmed COVID-19 cases incidence rate ratio (IRR) and ratio of CFR over different periods (wave 7, 2022-23 season, 2023-24 season), regions and LTCF bed capacity. A total of 2,501 outbreaks were recorded, corresponding to 39,089 COVID-19 cases (among residents and health care workers). The odds of an active outbreak, IRR of COVID-19 cases, and ratio of CFR declined significantly during the 2023-24 season compared to wave 7 (-35%, -39% and -24%, respectively; p-values < 0.0001). While larger LTCFs (≥ 40 beds) were up to 7 times more likely to have an active outbreak vs.10-39 beds, COVID-19 IRR and ratio of CFR were comparable across LTCFs' bed-capacity. In summary, the burden of COVID-19 on LTCF residents has declined from May 2022 to September 2024. Bed capacity seems to predict outbreak occurrence but not virus transmission within LTCFs.