Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada.
Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada.
Microbiol Spectr. 2022 Aug 31;10(4):e0021722. doi: 10.1128/spectrum.00217-22. Epub 2022 Jun 28.
The COVID-19 pandemic has been hallmarked by several waves of variants of concern (VoCs), each with novel challenges. Currently, the highly transmissible Omicron VoC is predominant worldwide, and sore throat is common, among other cold-like symptoms. Anecdotes on social media have suggested that sampling one's throat can increase the sensitivity for Omicron detection by antigen-based rapid testing devices (Ag-RDTs). This work aimed to improve the local testing strategy and determine whether the sensitivity of Ag-RDTs designed for nasal sampling is altered with the use of self-administered throat swabs in self-perceived asymptomatic individuals. This investigation used a common Ag-RDT (i.e., Abbott Panbio COVID-19 Ag rapid test device) to compare three sampling sites: nasal swab, throat swab, and combined nasal/throat. All Ag-RDT results were confirmed with molecular testing from residual test buffer. Compared to reverse transcriptase PCR (RT-PCR), samples from nasal or throat swabs each detected 64.5% of SARS-CoV-2 cases; however, combining the contributions of each swab increased the positive percent agreement (PPA) with RT-PCR to 88.7%. This trend was also evident with the Rapid Response Ag-RDT (BTNX), which uses more flexible swabs than does the Panbio. When nasal swab collection was compared to paired sampling of the nose/throat using a single swab with the Panbio Ag-RDT, the PPAs were 68.4% and 81.6%, respectively. No false-positive results were observed with nasal, throat, or combined nasal/throat sampling. Self-administered throat and nasal/throat swabs both had >90% acceptability. These findings support the use of self-collected combined nasal/throat sampling for Ag-RDT-based SARS-CoV-2 detection in self-perceived asymptomatic individuals. This quality project demonstrates that combining the results of nasal and throat swabs or using a combined single swab of the throat and nares resulted in increased detection of SARS-CoV-2 using a rapid antigen test, in an asymptomatic population. Importantly, no false positives were detected, and over 90% of people were willing to perform the combination swab. These types of projects are instrumental in informing local practices to improve testing strategies. These data support the option of using a combined nasal/throat swab in our local setting to enhance the detection of Omicron.
COVID-19 大流行的特点是出现了几波令人关注的变异株（VOC），每一波都带来了新的挑战。目前，高传染性的奥密克戎 VOC 在全球占主导地位，除了其他类似感冒的症状外，喉咙痛也很常见。社交媒体上的传闻表明，对喉咙进行采样可以提高抗原快速检测设备（Ag-RDT）检测奥密克戎的敏感性。这项工作旨在改进当地的检测策略，并确定在自我感知无症状个体中使用自我管理的喉咙拭子时，针对鼻腔采样设计的 Ag-RDT 的敏感性是否会发生变化。本研究使用一种常见的 Ag-RDT（即 Abbott Panbio COVID-19 Ag 快速检测设备）比较了三个采样部位：鼻腔拭子、喉咙拭子和鼻腔/喉咙联合采样。所有 Ag-RDT 结果均通过残留测试缓冲液的分子测试进行确认。与逆转录酶聚合酶链反应（RT-PCR）相比，来自鼻腔或喉咙拭子的样本分别检测到 64.5%的 SARS-CoV-2 病例；然而，结合每个拭子的贡献，将与 RT-PCR 的阳性百分率一致性（PPA）提高到 88.7%。这种趋势在 Rapid Response Ag-RDT（BTNX）中也很明显，该检测使用的拭子比 Panbio 更灵活。当与 Panbio Ag-RDT 相比时，比较鼻腔拭子与使用单个拭子对鼻腔/喉咙进行联合采样，PPA 分别为 68.4%和 81.6%。使用鼻腔、喉咙或鼻腔/喉咙联合采样均未观察到假阳性结果。自我管理的喉咙和鼻腔/喉咙拭子的可接受性均超过 90%。这些发现支持在自我感知无症状个体中使用自我采集的鼻腔/喉咙联合采样进行基于 Ag-RDT 的 SARS-CoV-2 检测。这个质量项目表明，在无症状人群中，使用快速抗原检测结合鼻腔和喉咙拭子的结果或使用喉咙和鼻腔的联合拭子，可提高对 SARS-CoV-2 的检测率。重要的是，没有检测到假阳性，超过 90%的人愿意进行联合拭子。这类项目有助于为改进检测策略提供当地实践信息。这些数据支持在我们的本地环境中选择使用鼻腔/喉咙联合拭子的方案，以提高对奥密克戎的检测率。
