Comparison of Throat Swab and Sputum Specimens For Viral Nucleic Acid Detection in 31 Cases of 2019-nCoV Infection/ 31例新型冠状病毒感染病例咽拭子与痰标本病毒核酸检测的比较

Objective To comparatively analyze the detection efficiency of viral nucleic acid in throat swab and sputum sample of 2019-nCoV cases． Methods Ribonucleoprotein (RNP) gene in human epithelial cells, viral ORF 1ab genes and N genes were tested and compared with real-time PCR in throat swabs and sputum specimens from 31 confirmed cases of 2019-nCoV． Results In the throat swabs and sputum samples of 31 cases, the RNP gene of human epithelial cells showed obvious and typical amplification signal curves In the detection of viral ORF1ab gene and N gene, the amplification signal of sputum samples was stronger than that of throat swab, and the cycle threshold (Ct) value of amplification curve was lower than that of throat swab, especially in case 9 and 16 were single gene positive, the pharyngeal swabs of the 9th and 16th patients were single gene positive, and the 17th patient was double gene positive, and the rest of the 28 patients were negative Sputum specimens collected at the same time showed that all the 18 patients were single gene positive and 13 were double gene positive Conclusion In the viral nucleic acid testing of 2019-nCoV laboratory detection, the virus content in sputum specimens was higher than that in throat swab specimens, and the detection efficiency was higher than that in throat swab specimens