The relationship between IgG and IgM levels and severity of symptoms in COVID-19 patients confirmed by rapid antigen test

Abstract

This study aims to measure immunoglobulin G (IgG) and immunoglobulin M (IgM) response after detection of Severe Acute Respiratory Syndrome coronavirus (SARS CoV-2) antigens in coronavirus disease 2019 (COVID-19) patients concerning the severity of symptoms. SARS CoV-2 antigen was confirmed by rapid antigen test, and IgG and IgM were confirmed by VIDAS® SARS-COV-2 IgM and VIDAS® SARS-CoV-2 IgG automated qualitative assays used to rapidly detect antibodies 20–30 days after detection. The serological assay for detecting SARS-CoV-2 IgM and IgG antibodies shows a positive correlation for all patients detected with SARS-CoV-2 antigen with sensitivity 100% with differences in antibodies levels between patients regarding age and significantly related clinical symptoms with p-value 0.013 <0.05. The appearance of clinical symptoms was not significantly related to IgG levels at a p-value of 0.4 >0.05. However, the appearance of clinical symptoms was significantly related to IgM levels at a p-value of 0.002 <0.05. Antigen-dependent rapid tests can be used to detect SARS-CoV-2 in an early stage of infection with high sensitivity and specificity. Moreover, this study shows the age groups 21–30 and 31–40 have a better response to SARS-CoV-2 infection.