Clinical application value of novel coronavirus antibody detection in the diagnosis of COVID-19

OBJECTIVE: To investigate the value of serum-specific antibody of 2019 novel coronavirus(2019-nCoV) in the diagnosis of Coronavirus Disease 2019(COVID-19).METHODS: The plasma samples of236 confirmed and 79 suspected patients with COVID-19 were detected by immunochromatography assays for 2019-nCoV total antibodies and IgM/IgG antibodies.The nucleic acids were detected by real-time fluorescent quantitative PCR.RESULTS: In the confirmed group of 236 cases, the positive rates of the two detection reagents were 86.02%(203/236) and 84.32%(199/236); Among the 79 suspected cases, the positive rates of the two agents were 78.48%(62/79) and 70.89%(56/79).The sensitivity, specificity, positive value(PPV), negative predictive value(NPV) and compliance rates of the two reagents were 86.02% and 84.32%, 96.61% and 96.61%, 99.02% and 99.00%,63.33% and 60.64%, 88.14% and 86.78%, respectively.There was no significant difference in the detection efficacy between the two reagents by statistical analysis(P>0.05).The positive rates of IgM and IgG were 73.31%(173/236) and 85.59%(202/236) in the COVID-19 confirmed group,and 12.66%(10/79) and 65.82%(52/79) in COVID-19 suspected group, respectively.There was a statistically significant difference in IgM positive rates between the two groups(P<0.01).CONCLUSION: Serum-specific antibody could be used as a valued index to evaluate 2019-nCoV infection, and IgM is efficient for the diagnosing and excluding the COVID-19 patients with negative nucleic acid tests.