Results analysis on SARS-CoV-2 nucleic acid detection based on different target gene detection

Abstract

Objective To compare the results of three SARS-CoV-2 nucleic acid detection reagents (reagent A, B and based on different target gene detection, and we analyze the consistency by preliminary evaluation of the application of each reagent. Methods Totally 43 samples of pharyngeal swabs were collected from our hospital and the designated treatment hospital, and detected by the real-time fluorescencereverse transcription-polymerase chain reaction (RT-PCR) in three SARS- CoV-2 nucleic acid detection reagent (reagent A, B and C) at the same time. Clinical diagnosis was divided into COVID-19 group ( n =31) and control group ( n =12). Fisher exact probability test and Kendall coordination coefficient W test were used to test the difference of positive rate and consistency of test results. Results The positive detection rate of reagent B was the highest at 90.32%, and there was no reexamination result.The positive detection rate of reagent A and reagent C were 77.42% and 74.19%, and more reexamination results were needed for reagent C. In the control group, reagent A and C did not test positive, but reagent B showed one positive result. The difference of positive detection rate among reagents was not statistically significant ( P >0.05), and the difference in consistency was statistically significant, with progressive significance Sig=0.00 and Kendall’s W coefficient value being 0.852, indicating that the consistency of test results of the three reagents was very high. Conclusion The three reagents showed good consistency in the nucleic acid test results for COVID-19. Reagent B has advantages in sensitivity, and reagent A and C are stable in specificity.Reagent B is most suitable for strict screening during an outbreak, but false positives should be noted. Reagent A and reagent C need to improve the quality of test samples for false negative and reexamination results, and the result interpretation method of reagent C is not good in the processing of large quantities of positive sample data. 摘要： 目的 比较三种不同靶基因检测 2019 新型冠状病毒(SARS-CoV-2)的检测结果，分析其一致性，初步评估各 试剂的应用情况。 方法 收集 43 份本院患者和定点治疗医院送来的咽拭子标本，根据临床诊断分为新型冠状病毒肺 炎(COVID-19)组 31 份和对照组 12 份，用三种 SARS-CoV-2 核酸检测试剂同时进行实时荧光逆转录聚合酶链反应(re⁃ verse transcription-polymerase chain reaction, RT-PCR)检测，检测结果的阳性率差异和一致性分别用 Fisher 精确概率检 验和 Kendall’s 协调系数 W 检验。 结果 在 COVID-19 组中试剂 B 的阳性检出率最高为 90.32%，且不存在需复检结果； 试剂 A 和试剂 C 的阳性检出率分别为 77.42% 和 74.19%，且试剂 C 出现的需复检结果较多；在对照组中试剂 A 和试剂 C 未检测出阳性，但试剂 B 出现一例阳性结果。COVID-19 组中各试剂的阳性检出率差异不具有统计学意义( P >0.05)；一 致性方面差异具有统计学意义，渐进显著性 Sig=0.00，Kendall’sW 系数值为 0.852，说明三种试剂检测结果的一致性程度 很高。 结论 三种试剂对 COVID-19 核酸检测的结果一致性很好，灵敏度方面试剂 B 较有优势，特异性方面试剂 A 和 试剂 C 较稳定。试剂 B 最适合疫情期间的严格排查，但应注意假阳性结果的出现；试剂 A 和试剂 C 针对假阴性和需复 检结果需要提高检测样本的质量，且试剂 C 的结果判读方式在处理大批量阳性标本数据时体验欠佳。