Serum levels of anti-corona virus specific -IgG and -IgM antibodies in COVID-19 patients at admission and at discharge

Introduction. Clear understanding of duration of antibody based protective immunity following natural infection with SARSCoV- 2 will give idea about the efficacy of proposed prophylactic vaccines against SARS-CoV-2, establishment of herd immunity and use of convalescent plasma. Aim. This study clarified the kinetics and magnitude of the initial antibody response against SARS-CoV-2 in a cohort of symptomatic COVID-19 patients from Ibadan, Nigeria. Material and methods. This study quantified immunoglobulin M (IgM) and G (IgG) antibodies recognizing the SARS-CoV-2 Spike (S) protein in 35 symptomatic COVID-19 patients at admission and at discharge using ELISA. Results. CovIgG was positive in none (0)% and 20% of COVID-19 patients at admission and at discharge respectively while CovIgM was positive in 54% and 69% of COVID-19 patients at admission and at discharged respectively. The level of CovIgG was significantly higher in COVID-19 patients at discharge compared with the level at admission while the level of CovIgM was insignificantly reduced in COVID-19 patients at discharge compared with the level at admission. Conclusion. The data indicates increased anti-SARS-COV-2 IgG Spike antibody in symptomatic COVID-19 at discharge, thus providing basis for antibody-based therapies to treat COVID-19 patients.