Instituto Nacional de Investigación en Salud Pública (INSPI), Ecuador.
Emory University, Department of Medicine, Division if Infectious Diseases, Atlanta, GA, USA.
J Virol Methods. 2021 Dec;298:114302. doi: 10.1016/j.jviromet.2021.114302. Epub 2021 Sep 23.
Standard diagnoses of SARS-CoV-2 infections are done by RNA extraction and real-time RT-PCR (rRT-PCR). However, the need for RNA extraction complicates testing due to increased processing time, high cost, and limited availability of commercial kits. Therefore, alternative methods for rRT-PCR detection of SARS-CoV-2 without RNA extraction were investigated. Nasopharyngeal and sputum samples were used to compare the sensitivity of three techniques: Trizol RNA extraction, thermal shock, and the direct use of samples with an RNase inhibitor. Direct, extraction-free use of primary samples plus the RNase inhibitor produced diagnostic values of 100 % sensitivity and specificity compared to standard protocols, and these findings were validated in a second, independent laboratory.
SARS-CoV-2 感染的标准诊断是通过 RNA 提取和实时 RT-PCR（rRT-PCR）进行的。然而，由于增加了处理时间、高成本以及商业试剂盒的有限可用性，RNA 提取使检测变得复杂。因此，研究了无需 RNA 提取即可进行 rRT-PCR 检测 SARS-CoV-2 的替代方法。使用鼻咽和痰液样本比较了三种技术的敏感性：Trizol RNA 提取、热休克和直接使用带 RNase 抑制剂的样本。与标准方案相比，直接、无需提取的使用初级样本加 RNase 抑制剂产生了 100%的灵敏度和特异性的诊断价值，这些发现得到了第二个独立实验室的验证。
