Mokashi Vaibhav, Gilchrist Jodi, Smieja Nicole, Maciejewski Julia, Marttala Sarah, Beal Kerry, Mbuagbaw Lawrence, Bulir David, Smieja Marek, O'Shea Tim
Department of Medicine, McMaster University, Hamilton, ON, Canada.
The Research Institute of St. Joseph's Hamilton, Hamilton, ON, Canada.
BMC Infect Dis. 2024 Dec 28;24(1):1478. doi: 10.1186/s12879-024-10148-y.
To compare the effectiveness of four surveillance strategies for detecting SARS-CoV-2 within the homeless shelter population in Hamilton, ON and assess participant adherence over time for each surveillance method.
This was an open-label, cluster-randomized controlled trial conducted in eleven homeless shelters in Hamilton, Ontario, from April 2020 to January 2021. All participants who consented to the study and participated in the surveillance were eligible for testing by self-swabbing. SARS-CoV-2 detection rate as the primary outcome, number of outbreaks, adherence, and overall acceptability were assessed. All participants, which included staff and residents, underwent daily symptom surveillance conducted by shelter staff and shelters were allocated to one of three asymptomatic surveillance arms (once weekly, self-collected oral swabs (OS); once-weekly self-collected oral-nasal swab (ONS); or once-weekly nurse collected nasopharyngeal swab (NPS) or a symptomatic only SARS-CoV-2 testing arm.
A total of 9747 SARS-CoV-2 tests were performed on 1570 participants. There were 4527 participants allocated to oral swab collection and 4935 participants allocated to oral-nasal swab collection. For nasopharyngeal swab collection, 285 participants were assigned before this arm was discontinued. The OS group identified 5 new cases (1.1 per 1000; 95% CI 0.4-2.3), while the ONS group identified 15 new cases (3.0 per 1000; 95% CI 1.9-4.7), resulting in a Risk Ratio (RR) of 2.76 (95% CI 1.00-7.58; p = 0.040). However, the mixed-effect model did not show a significantly higher positivity rate in the ONS compared to OS (OR 1.64; 95% CI 0.76-9.14; p = 0.129). Both ONS and OS were preferred over NPS, which did not detect any cases due to low adherence. Three outbreaks were identified during the study period within the shelters, two of the outbreaks had 2 positive cases each and the third outbreak had 3 positive cases.
The two self-collection strategies were superior and showed the best adherence, with the ONS strategy shown to be superior or non-inferior in all measures. We are now studying the operationalization of a large-scale self-collected ONS surveillance strategy in a prospective cohort study of multiple homeless shelters. Funding was provided by the Hamilton Academic Hospital Organization (HAHSO) and Research St. Joseph's - Hamilton.
The trial was retrospectively registered with ClinicalTrials.gov on June 18, 2020, with the identifier NCT04438070.
比较安大略省汉密尔顿市无家可归者收容所人群中四种检测严重急性呼吸综合征冠状病毒2（SARS-CoV-2）的监测策略的有效性，并评估每种监测方法参与者随时间的依从性。
这是一项开放标签、整群随机对照试验，于2020年4月至2021年1月在安大略省汉密尔顿市的11个无家可归者收容所进行。所有同意参与研究并接受监测的参与者都有资格通过自行采样进行检测。评估SARS-CoV-2检测率作为主要结果、疫情爆发次数、依从性和总体可接受性。所有参与者，包括工作人员和居民，都接受了收容所工作人员进行的每日症状监测，收容所被分配到三个无症状监测组之一（每周一次自行采集口腔拭子（OS）；每周一次自行采集口鼻拭子（ONS）；或每周一次护士采集鼻咽拭子（NPS））或仅进行有症状的SARS-CoV-2检测组。
对1570名参与者进行了总共9747次SARS-CoV-2检测。4527名参与者被分配进行口腔拭子采集，4935名参与者被分配进行口鼻拭子采集。对于鼻咽拭子采集，在该组停止前有285名参与者被分配。OS组发现了5例新病例（每1000人中有1.1例；95%置信区间0.4 - 2.3），而ONS组发现了15例新病例（每1000人中有3.0例；95%置信区间1.9 - 4.7），风险比（RR）为2.76（95%置信区间1.00 - 7.58；p = 0.040）。然而，混合效应模型显示ONS组的阳性率与OS组相比没有显著更高（优势比1.64；95%置信区间0.76 - 9.14；p = 0.129）。ONS和OS都比NPS更受青睐，由于依从性低，NPS未检测到任何病例。在研究期间，收容所内发现了3次疫情爆发，其中2次疫情爆发各有2例阳性病例，第三次疫情爆发有3例阳性病例。
两种自行采集策略更优且显示出最佳依从性，ONS策略在所有指标上显示出更优或非劣效。我们现在正在一项针对多个无家可归者收容所的前瞻性队列研究中研究大规模自行采集ONS监测策略的实施。资金由汉密尔顿学术医院组织（HAHSO）和汉密尔顿圣约瑟夫医院提供。
该试验于2020年6月18日在ClinicalTrials.gov上进行回顾性注册，标识符为NCT04438070。
