Xia Yiqing, Ma Huiting, Malikov Kamil, Straus Sharon E, Fahim Christine, Moloney Gary, Huang Qing, Asgari Sahar, Boyd Jamie M, Ferro Irene, Johns Jaimie, Khan Kamran, Mistry Jaydeep, Wang Linwei, Chan Adrienne K, Baral Stefan D, Maheu-Giroux Mathieu, Mishra Sharmistha
Department of Epidemiology and Biostatistics, School of Population and Global Health, McGill University, Montréal, Québec, Canada.
Centre for Urban Health Solutions, Li Ka Shing Knowledge Institute, University of Toronto, 209 Victoria St, Toronto, ON, M5B 1T8, Canada.
BMC Public Health. 2025 Aug 2;25(1):2634. doi: 10.1186/s12889-025-23621-3.
To examine the relationship between individual workers employed at more than one LTCH (inter-LTCH connectivity) across LTCH and SARS-CoV-2 outbreaks.
We conducted a retrospective cohort study using secondary, aggregate data (surveillance and mobile geolocation data) from 179 LTCH in the Greater Toronto Area of Ontario, the province where close to one-third of the Canada's SARS-CoV-2 cases among long-term care homes residents were reported, between 2020-02-26 and 2020-08-31. The main exposure of interest was the inter-LTCH connectivity, generated from geographic location data procured across mobile apps. Three outcomes were examined: 1) at least one SARS-CoV-2 diagnosis among residents, 2) cumulative cases among residents in each facility, and 3) time to first outbreak.
The median degree of connectivity for LTCH that experienced an outbreak (59%; 106/179) was 1.2 times the degree of those without an outbreak (6 compared to 5). LTCH with higher inter-LTCH connectivity also had larger numbers of residents and beds, and were more likely to have for-profit ownership. After adjusting for facility-level and neighbourhood-level factors, every additional connection to another LTCH increased the odds of an outbreak in the respective LTCH by 8% (adjusted odds ratio=1.08, 90% credible interval [CrI]: 1.02-1.09). Inter-LTCH connectivity was also associated with higher risk of earlier occurrence of a first SARS-CoV-2 case (adjusted hazard ratio=1.05, 90%CrI: 1.02-1.09), but not with outbreak size.
Staff cohorting was associated with reduced importation risk of SARS-CoV-2 cases into LTCH. However, once importation has occurred, other facility-level factors including facility infrastructure and staff benefits are more important in shaping outbreak size. Implementing these structural strategies to meet the LTCH workers and residents' needs are pivotal to prevent and manage future respiratory virus outbreaks.
研究在多个长期护理机构工作的个体员工（长期护理机构间的连通性）与严重急性呼吸综合征冠状病毒2（SARS-CoV-2）疫情之间的关系。
我们使用安大略省大多伦多地区179家长期护理机构的二级汇总数据（监测和移动地理位置数据）进行了一项回顾性队列研究。该省报告了近三分之一在长期护理机构居民中的SARS-CoV-2病例，时间跨度为2020年2月26日至2020年8月31日。主要关注的暴露因素是长期护理机构间的连通性，由通过移动应用获取的地理位置数据生成。研究了三个结果：1）居民中至少有一例SARS-CoV-2诊断；2）每个机构居民中的累积病例数；3）首次爆发的时间。
发生疫情的长期护理机构的连通性中位数（59%；106/179）是未发生疫情的机构的1.2倍（分别为5和6）。长期护理机构间连通性较高的机构居民和床位数量也较多，且更有可能为营利性机构。在调整了机构层面和社区层面的因素后，与另一家长期护理机构的每一次额外联系都会使相应长期护理机构爆发疫情的几率增加8%（调整后的优势比=1.08，90%可信区间[CrI]：1.02 - 1.09）。长期护理机构间的连通性还与首次出现SARS-CoV-2病例的风险较高相关（调整后的风险比=1.05，90%CrI：1.02 - 1.09），但与疫情规模无关。
员工分组与降低SARS-CoV-2病例输入到长期护理机构的风险相关。然而，一旦发生输入，包括机构基础设施和员工福利在内的其他机构层面因素在决定疫情规模方面更为重要。实施这些结构性策略以满足长期护理机构工作人员和居民的需求对于预防和管理未来的呼吸道病毒疫情至关重要。
