Production of SARS-CoV-2 Antibodies and Emergence of the Clinical Symptoms of COVID-19.

Hormati, Ahmad; Poustchi, Hossein; Ghadir, Mohammad Reza; Jafari, Saeede; Jafari, Narges; Ashtari, Abdolreza; Ahmadpour, Sajjad

Coronavirus disease 2019 (COVID-19) is a worldwide public health problem that has attracted much attention due to its clinical findings. Measurement of IgG and IgM antibodies is of great importance for researchers and it will help to develop a new diagnostic and therapeutic method in clinical care. In this cross-sectional study, we aim to measure the IgG and IgM antibody levels in 401 suspected COVID-19 volunteers. We also measure the time duration for the appearance of IgG and IgM antibodies from the onset of symptoms to sampling time. Of 401 participants enrolled in the study, 255 (63.59%) were healthy, 79 (19.70%) were a carrier, 59 (14.71%) were cured and 8 (1.99%) were borderline. Of 142 subjects diagnosed with COVID-19, 41 (28.87%) presented with gastrointestinal (GI) symptoms, 83 (58.45%) had no GI symptoms, and 18 (12.68%) were asymptomatic. According to our findings, the measurement of IgG and IgM antibodies will provide the tool for the diagnosis of COVID-19 and significantly boost research into novel diagnostic and therapeutic approaches.