Value of swab types and collection time on SARS-COV-2 detection using RT-PCR assay
Value of swab types and collection time on SARS-COV-2 detection using RT-PCR assay
复制标题
使用 RT-PCR 检测拭子类型和采集时间对 SARS-COV-2 检测的价值
DOI：
10.1016/j.jviromet.2020.113974
复制
发表时间：
2020-12-01
影响因子：
3.1
通讯作者：
Luo, Chunhua
中科院分区：
文献类型：
--
作者：
Liu, Min;Li, Qianyuan;Luo, Chunhua
目的：SARS-CoV-2感染者在感染后期病毒载量较低，容易出现假阴性核酸检测结果，给当前疫情的防控带来很大挑战。本研究主要针对2019年新型冠状病毒感染晚期患者标本类型和采集时间点进行RT-PCR检测。方法：采集感染晚期SARS-CoV-2患者鼻咽拭子、鼻拭子、口咽拭子和肛拭子，并于当天上午和下午洗涤。24 h内提取病毒RNA，RT-PCR检测2019-nCoV。结果：感染后期病毒载量较低。早上洗澡前采集的标本会增加2019-nCoV的检出率。鼻咽拭子[65(95%CI：49.51~77.87)vs 42.5(95%CI：28.51~57.8)]或鼻拭子[57.5(95%CI：42.2~71.49)vs 35(95%CI：22.13~50.49)]的检出率不仅高于口咽拭子[22.5(95%CI：12.32~37.5)vs 7.5(95%CI：2.58~19.86)]，而肛拭子[2.5(95%CI：0.44~12.88)vs 5(95%CI：1.38~16.5)]。结论：本研究发现早晨洗涤前采集的鼻咽或鼻拭子可能更适合于检测感染后期低载量SARSCoV-2患者的大量标本。这些结果可以帮助其他实验室收集适当的标本，以改进感染后期患者的SARS-CoV-2检测以及初步筛查。
Objective: Low viral load from patients infected with SARS-CoV-2 during infection late stage easily lead to false negative nucleic acid testing results, thus having great challenges to the prevention and control of the current pandemic. In present study, we mainly aimed to evaluate specimen types and specimen collection timepoint on the positive detection of 2019 novel coronavirus from patients at infection late stage based on RT-PCR testing.Methods: Paired nasopharyngeal swabs, nasal swabs, oropharyngeal swabs and anal swabs were collected from patients infected with SARS-CoV-2 during infection late stage before washing in the morning and afternoon on the same day. Then virus RNA was extracted and tested for 2019-nCoV identification by RT-PCR within 24 h.Results: Viral load was low at late infection stage. Specimens collected before washing in the morning would increase the detection ratio of 2019-nCoV. Detection ratio of nasopharyngeal swab [65 (95 % CI: 49.51-77.87) vs 42.5(95 % CI: 28.51-57.8)] or nasal swab [57.5 (95 % CI: 42.2-71.49) vs 35 (95 % CI: 22.13-50.49)] is higher not only than oropharyngeal swab[22.5 (95 % CI: 12.32-37.5) vs 7.5 (95 % CI: 2.58-19.86)], but also anal swab [2.5 (95 % CI: 0.44-12.88) vs 5 (95 % CI: 1.38-16.5)].Conclusions: In summary, our research discovers that nasopharyngeal or nasal swab collected before washing in the morning might be more suitable for detecting of large-scale specimens from patients infected with low SARSCoV-2 load during infection late stage. Those results could facilitate other laboratories in collecting appropriate specimens for improving detection of SARS-CoV-2 from patients during infection late stage as well as initially screening.