In March 2020, WHO declared a pandemic state due to SARS-CoV-2 having spread. TaqMan-based real-time RT-qPCR is currently the gold standard for COVID-19 diagnosis. However, it is a high-cost assay, inaccessible for the majority of laboratories around the world, making it difficult to diagnose on a large scale. The objective of this study was to standardize lower cost molecular methods for SARS-CoV-2 identification. E gene primers previously determined for TaqMan assays by Colman et al. (2020) were adapted in SYBR Green assay and RT-PCR conventional. The cross-reactivity test was performed with 17 positive samples for other respiratory viruses, and the sensibility test was performed with 8 dilutions (10 based) of SARS-CoV-2 isolated and 63 SARS-CoV-2-positive samples. The SYBR Green assays and conventional RT-PCR have not shown amplification of the 17 respiratory samples positives for other viruses. The SYBR Green-based assay was able to detect all 8 dilutions of the isolate. The conventional PCR detected until 107 dilution, both assays detected the majority of the 63 samples, 98.42% of positivity in SYBR Green, and 93% in conventional PCR. The average Ct variation between SYBR Green and TaqMan was 1.92 and the highest Ct detected by conventional PCR was 35.98. Both of the proposed assays are less sensitive than the current gold standard; however, our data shows a low sensibility variation, suggesting that these methods could be used by laboratories as a lower cost molecular method for SARS-CoV-2 diagnosis. Electronic supplementary material The online version of this article (10.1007/s42770-020-00347-5) contains supplementary material, which is available to authorized users.

中文翻译：

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COVID-19 分子诊断的低成本替代方案：常规 RT-PCR 和基于 SYBR Green 的 RT-qPCR

2020 年 3 月，由于 SARS-CoV-2 的传播，世卫组织宣布进入大流行状态。基于 TaqMan 的实时 RT-qPCR 目前是 COVID-19 诊断的金标准。然而，它是一种成本高昂的检测方法，世界上大多数实验室都无法使用，因此难以大规模诊断。本研究的目的是标准化用于 SARS-CoV-2 鉴定的低成本分子方法。先前由 Colman 等人为 TaqMan 测定确定的 E 基因引物。(2020) 在 SYBR Green 测定和 RT-PCR 常规中进行了调整。对 17 份其他呼吸道病毒阳性样本进行了交叉反应性测试，对 SARS-CoV-2 分离的 8 份稀释液（10 份）和 63 份 SARS-CoV-2 阳性样本进行了敏感性测试。SYBR Green 检测和常规 RT-PCR 未显示其他病毒阳性的 17 个呼吸道样本的扩增。基于 SYBR Green 的测定能够检测分离物的所有 8 种稀释度。常规 PCR 检测到 107 稀释，这两种测定都检测到 63 个样品中的大部分，SYBR Green 中的阳性率为 98.42%，常规 PCR 中为 93%。SYBR Green 和 TaqMan 之间的平均 Ct 变异为 1.92，常规 PCR 检测到的最高 Ct 为 35.98。两种提议的检测方法都不如当前的金标准敏感；然而，我们的数据显示出低敏感性变异，这表明实验室可以将这些方法用作 SARS-CoV-2 诊断的低成本分子方法。电子补充材料本文的网络版（10.