Association of Anti-SARS-CoV-2 Virus IgG antibody levels in COVID-19 recovered individuals with age, gender, blood group and computerized tomography severity index

Abstract

Introduction: The continued spread of corona virus disease 2019 (COVID-19) has prompted widespread concern around the world. Currently, the antibody responses against SARS-CoV-2 remain poorly understood and the clinical utility of serological testing is unclear.Aim: To study association of anti-SARS-CoV-2 IgG antibody levels in COVID-19 recovered individuals with age, gender, blood group and computerized tomography (CT) severity index.Material and methods: This cross sectional observational study was done in the department of Transfusion Medicine, Sri Venkateswara Institute of Medical Sciences, Tirupati from April 2020 to June 2020. CT severity index was classified into mild, moderate and severe depending on the CT score. Anti-SARS-CoV-2 IgG antibodies were measured by enhanced chemiluminescence immunoassay technology and signal to cutoff ratio was measured. The collected data was analyzed using SPSS 21.0, continuous data by Mann Whitney U test and categorical data by Fisher’s exact test.Results: The mean age of study population was 45.4 years with majority of the study population between 41-50 years (36.8%). Males constituted 57.9% and remaining 42.1% were females. The most common blood group was B positive (42.1%) followed by O (36.8%) and ‘A’ positive (21.1%). Majority of study population (57.9%) had severe CT severity index. Anti-SARS-CoV-2 IgG antibody levels with S/C ratio of <9.5 belongs to 42.1%, remaining 57.9% had >9.5 (S/C).Conclusion: The significant association between CT severity index and SARS CoV-2 IgG antibodies may be helpful to select convalescent plasma donors for the centres where the facilities for SARS CoV-2 IgG antibodies testing are not available.