A Study on Antibody Response among COVID-19 Noninfected Population – Need for Hour

Abstract

Abstract Introduction: In the year 2020, COVID-19 emerged as a pandemic resulting in millions of deaths worldwide and negatively impacted the health, infrastructure, and economy of the globe. The disease was believed to be acquired from animals (Bats), however, man-to-man transmission happened through aerosols o/or and direct contact. Seroprevalence studies in different countries among various populations were conducted to understand the immune responses against the virus; also, to estimate the proximity in reaching herd immunity. Aim: The aim of this study was to study antibody response among the COVID-19 noninfected population. Materials and Methods: A prospective cross-sectional study was done during the months of January–February 2023. The study was conducted in the Viral Research and Diagnostic Laboratory, Department of Microbiology, Osmania Medical College. Nursing and Diploma in Medical Laboratory Technology (DMLT) students who did not test positive for COVID-19 reverse transcription–polymerase chain reaction during and after the pandemic were included in the study. Blood samples were tested for COVID-19 immunoglobulin (Ig) G antibodies using commercial enzyme-linked immunosorbent assay kit. A comparison among vaccinated and nonvaccinated groups was performed. Results: A total of 90 blood samples were tested, of which 45 belonged to the vaccinated group and the other 45 were of the nonvaccinated group. Among the vaccinated group, total of 45 samples tested positive for COVID-19 IgG antibodies (100%). Whereas 38 (84.4%) among the nonvaccinated group showed positive COVID-19 IgG antibodies; while 7 (15.6%) samples of nonvaccinated group tested negative for antibodies. A total of 83 out of 90 (92.2%) showed evidence of COVID-19 IgG antibodies. Conclusion: Despite the controlled COVID-19 pandemic situation, the novel disease has posed serious challenges to the medical field. Although the population in this study showed good serological response, herd immunity to COVID-19 can be achieved if more than 80% of the entire population becomes immune. In this study, 84.4% of the population showed positive for COVID-19 IgG antibodies hinting toward achieving herd immunity. However, regular vaccination and sero-surveillance studies are needed for sustaining community protection.