Joint Detection of Serum IgM/IgG Antibody is An Important Key to Clinical Diagnosis of SARS-COV-2 Infection

Hu, Fang; Shang, Xiaoling; Chen, Meizhou; Zhang, Changliang

Background: This study was aimed to investigate the application of SARS- COV-2 IgM and IgG antibodies in diagnosis of COVID-19 infection. Method: This study enrolled a total of 178 patients at Huangshi Central Hospital from January to February, 2020. Among them, 68 patients were SARS-COV-2 infected confirmed with nucleic acid test (NAT) and CT imaging. 9 patients were in the suspected group (NAT negative) with fever and other respiratory symptoms. 101 patients were in the control group with other diseases and negative to SARS-COV-2 infection. After serum samples were collected, SARS-COV-2 IgG and IgM antibodies were tested by chemiluminescence immunoassay (CLIA) for all patients. Results: The specificity of serum IgM and IgG antibodies to SARS-COV-2 were 99.01% (100/101) and 96.04% (97/101) respectively, and the sensitivity were 88.24% (60/68) and 97.06% (66/68) respectively. The combined detection rate of SARS-COV-2 IgM and IgG antibodies were 98.53% (67/68). Conclusion: Combined detection of serum SARS-COV-2 IgM and IgG antibodies had better sensitivity compared with single IgM or IgG test, which can be used as an important diagnostic tool for SARS-COV-2 infection and a screening tool of potential SARS-COV-2 carriers in clinics, hospitals and accredited scientific laboratory.