Introduction. Non-invasive sample collection and viral sterilizing buffers have independently enabled workflows for more widespread COVID-19 testing by reverse-transcriptase polymerase chain reaction (RT-PCR). Gap statement. The combined use of sterilizing buffers across non-invasive sample types to optimize sensitive, accessible, and biosafe sampling methods has not been directly and systematically compared. Aim. We aimed to evaluate diagnostic yield across different non-invasive samples with standard viral transport media (VTM) versus a sterilizing buffer eNAT- (Copan diagnostics Murrieta, CA) in a point-of-care diagnostic assay system. Methods. We prospectively collected 84 sets of nasal swabs, oral swabs, and saliva, from 52 COVID-19 RT-PCR-confirmed patients, and nasopharyngeal (NP) swabs from 37 patients. Nasal swabs, oral swabs, and saliva were placed in either VTM or eNAT, prior to testing with the Xpert Xpress SARS-CoV-2 (Xpert). The sensitivity of each sampling strategy was compared using a composite positive standard. Results. Swab specimens collected in eNAT showed an overall superior sensitivity compared to swabs in VTM (70 % vs 57 %, P=0.0022). Direct saliva 90.5 %, (95 % CI: 82 %, 95 %), followed by NP swabs in VTM and saliva in eNAT, was significantly more sensitive than nasal swabs in VTM (50 %, P<0.001) or eNAT (67.8 %, P=0.0012) and oral swabs in VTM (50 %, P<0.0001) or eNAT (58 %, P<0.0001). Saliva and use of eNAT buffer each increased detection of SARS-CoV-2 with the Xpert; however, no single sample matrix identified all positive cases. Conclusion. Saliva and eNAT sterilizing buffer can enhance safe and sensitive detection of COVID-19 using point-of-care GeneXpert instruments.

中文翻译：

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提高 COVID-19 RT-PCR 检测的产量、可及性和生物安全性的样本收集和运输策略

介绍。非侵入性样本收集和病毒灭菌缓冲液独立启用了工作流程，可通过逆转录酶聚合酶链反应 (RT-PCR) 进行更广泛的 COVID-19 测试。间隙声明。尚未直接和系统地比较跨非侵入性样本类型的灭菌缓冲液的组合使用以优化敏感、可访问和生物安全的采样方法。目标。我们的目的是在即时诊断分析系统中评估不同非侵入性样本的诊断率，使用标准病毒转运介质 (VTM) 与灭菌缓冲液 eNAT-（Copan 诊断 Murrieta，CA）。方法。我们前瞻性地收集了来自 52 名 COVID-19 RT-PCR 确诊患者的 84 组鼻拭子、口腔拭子和唾液，以及来自 37 名患者的鼻咽 (NP) 拭子。在使用 Xpert Xpress SARS-CoV-2 (Xpert) 进行测试之前，将鼻拭子、口腔拭子和唾液放入 VTM 或 eNAT 中。使用复合阳性标准比较每个采样策略的灵敏度。结果。与 VTM 中的拭子相比，在 eNAT 中收集的拭子样本显示出整体优越的灵敏度（70 % 对 57 %，P = 0.0022）。直接唾液 90.5 % (95 % CI: 82 %, 95 %)，其次是 VTM 中的 NP 拭子和 eNAT 中的唾液，明显比 VTM 中的鼻拭子 (50 %，P <0.001) 或 eNAT (67.8 %)更敏感, P=0.0012) 和 VTM (50%, P <0.0001) 或 eNAT (58%, P <0.0001) 中的口腔拭子。唾液和 eNAT 缓冲液的使用都增加了 Xpert 对 SARS-CoV-2 的检测；然而，没有一个样本矩阵能识别所有阳性病例。结论。唾液和 eNAT 灭菌缓冲液可以使用即时护理 GeneXpert 仪器增强对 COVID-19 的安全和灵敏检测。