Assessment of Antibody Titers after SARS-CoV-2 Vaccination in Bangladesh: A Single Centre Observational Study

Abstract

The SARS-CoV-2 virus, which emerged in Wuhan, China in 2019, led to the COVID-19 pandemic, posing a global healthcare challenge. The primary pathology involves viral replication in the early disease stages. COVID-19 vaccines play a crucial role in reducing susceptibility to future infections. Evaluating antibody levels and longevity post-vaccination is essential to assess vaccine effectiveness. This study aims to quantify antibody levels among hospital employees to analyze the immune response to vaccination.
Methods: A single-center study was conducted to measure antibody levels among hospital employees. Data were collected from medical records, including the number of days post-vaccination (first and second doses), age, and antibody titers. Antibody titers were analyzed using a commercial Anti-SARS-CoV-2 kit. The study also examined antibody responses in individuals who had spontaneous SARS-CoV-2 infections post-vaccination. Results: There was a positive correlation between age and antibody titer. In COVID-19-positive individuals, a positive correlation was found between antibody titer and the duration between the first and second vaccine doses. In COVID-negative individuals, a negative correlation was observed. Male antibody titers had a skewness of 3.2, while female titers had a skewness of 2.6. Individuals who did not receive both vaccine doses had mean antibody titre 880.74 Au/ml and to those who received both doses 5530.11 Au/ml. Conclusions: COVID-19-positive individuals showed a stronger immune response post-vaccination. Despite waning immunity over time, vaccination led to significantly higher antibody titers in adults, reinforcing the importance of full-dose COVID-19 vaccination.