Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha.
Nebraska Public Health Laboratory, University of Nebraska Medical Center, Omaha.
Am J Clin Pathol. 2020 May 5;153(6):715-718. doi: 10.1093/ajcp/aqaa064.
To establish the optimal parameters for group testing of pooled specimens for the detection of SARS-CoV-2.
The most efficient pool size was determined to be five specimens using a web-based application. From this analysis, 25 experimental pools were created using 50 µL from one SARS-CoV-2 positive nasopharyngeal specimen mixed with 4 negative patient specimens (50 µL each) for a total volume of 250 µL. Viral RNA was subsequently extracted from each pool and tested using the CDC SARS-CoV-2 RT-PCR assay. Positive pools were consequently split into individual specimens and tested by extraction and PCR. This method was also tested on an unselected group of 60 nasopharyngeal specimens grouped into 12 pools.
All 25 pools were positive with cycle threshold (Ct) values within 0 and 5.03 Ct of the original individual specimens. The analysis of 60 specimens determined that 2 pools were positive followed by identification of 2 individual specimens among the 60 tested. This testing was accomplished while using 22 extractions/PCR tests, a savings of 38 reactions.
When the incidence rate of SARS-CoV-2 infection is 10% or less, group testing will result in the saving of reagents and personnel time with an overall increase in testing capability of at least 69%.
确定用于 SARS-CoV-2 检测的混合标本组检测的最佳参数。
使用基于网络的应用程序确定最佳的池大小为五个标本。在此分析的基础上，使用 50µL 的一个 SARS-CoV-2 阳性鼻咽标本与 4 个阴性患者标本（每个 50µL）混合创建了 25 个实验池，总容量为 250µL。随后从每个池中提取病毒 RNA，并使用 CDC SARS-CoV-2 RT-PCR 检测进行检测。阳性池随后被分成单独的标本，并通过提取和 PCR 进行检测。该方法还在 60 个未选择的鼻咽标本组中进行了测试，分为 12 个池。
所有 25 个池的 Ct 值均为 0 至 5.03，与原始单个标本的 Ct 值相同。对 60 个标本的分析表明，有 2 个池呈阳性，随后在 60 个测试标本中鉴定出 2 个单独的标本。在这一检测过程中，共使用了 22 次提取/PCR 检测，节省了 38 次反应。
当 SARS-CoV-2 感染的发病率为 10%或更低时，组检测将节省试剂和人员时间，同时至少提高 69%的整体检测能力。
