Anti-SARS-CoV-2 antibodies among vaccinated healthcare workers: Repeated cross-sectional study

BACKGROUND: Since the novel SARS-CoV-2 has been detected and the ensuing pandemic, the search for a cure or prevention has been the only target of the medical fraternity. As the second wave racked havoc, vaccines seemed to be the only viable option to stop this global surge. World Health Organization (WHO) and subsequently the Government of India have issued emergency use authorization to two vaccines. Our study aims to estimate the prevalence of the anti-SARS-CoV-2 antibodies and identify predictors of antibody titers in vaccinated healthcare workers in VIMSAR, Burla. METHODS: This is a part of the ongoing, repeated cross-sectional study. Participants were enrolled well above the sample size (322) to increase precision. Two rounds of the survey were conducted and are being reported. Serum IgG antibodies against spike protein of SARS-CoV-2 were estimated using Elecsys(®) anti-SARS-CoV-2S is an immunoassay by ECLIA-based Cobas e411 analyzer. Univariate and multivariate regression were used in statistical analysis. RESULTS: Our results show that 95.1% and 99.5% of the vaccinated individuals have developed antispike protein antibodies after the first and second doses, respectively. Previous COVID-19 infection was significantly correlated with antibody production, and age was negatively correlated. No difference was reported for sex, occupation, and diabetes. CONCLUSION: Our interim analysis report is coherent with the available literature and research regarding the high efficacy of the COVID-19 vaccine as far as seroconversion is concerned.