Abstract
Background
A novel coronavirus, SARS-CoV-2, has recently emerged and caused the rapid spread of COVID-19 worldwide.
Methods
We did a retrospective study and included COVID-19 patients admitted to Renmin Hospital of Wuhan University between February 1 and February 29, 2020. Antibody assay was conducted to detect COVID-19 envelope protein E and nucleocapsid protein N antigen.
Results
112 patients were recruited with symptoms of fever, cough, fatigue, myalgia, and diarrhoea. All patients underwent antibody tests. Fifty-eight (51.79%) were positive for both IgM and IgG, 7 (6.25%) were negative for both antibodies, 1 (0.89%) was positive for only IgM, and 46 (41.07%) were positive for only IgG. IgM antibody appeared within a week post disease onset, and lasted for one month and gradually decreased, while IgG antibody was produced 10 days after infection, and lasted for a longer time. However, no significant difference in level of IgM and IgG antibody between positive and negative patients of nucleic acid test after treatment was found.
Conclusions
Our results indicate that serological tests could be powerful approach for the early diagnosis of COVID-19.
Keywords: SARS-CoV-2, COVID-19, antibody, serological test, humoral immunity