DOI: https://doi.org/10.36347/sjams.2024.v12i12.026

Pages: 1859-1865

Background: SARS-CoV-2, the virus responsible for COVID-19, has prompted global vaccination efforts, including booster doses to enhance immunity. The persistence of antibodies following booster vaccination is a critical area of study. The decay rate of antibodies can vary based on vaccine type, age, and individual immune response. This study aimed to evaluate the temporal decline of SARS-CoV-2 antibodies post-booster dose among the doctors at Bangabandhu Sheikh Mujib Medical University. Methods: This prospective observational study was conducted at the Department of Biochemistry & Molecular Biology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from March 2022 to February 2023. A total of 80 doctors of BSMMU aged between 25 to 65 years who had taken the COVID-19 booster dose about 6–8 months ago were enrolled in this study as the study subjects purposively. Data were analyzed by the SPSS version 26.0 program. Results: Comparing serum IgG levels 6-8 month’s post-booster versus 3 months after, there was a significant decrease at 3-month intervals (p<0.001). This decline was consistent at 6, 7, and 8 months (p<0.05) across genders, infection and vaccination statuses, age groups (25-44 and 45-65), BMI categories (except normal weight participants p>0.05), and in those with comorbidities (DM, HTN). While all booster types showed a decrease, the Moderna vaccine showed a non-significant decline (p>0.05) compared to the others, which had significant reductions (p<0.05). Conclusion: The antibody level decays significantly with time after taking the booster dose. Serum IgG levels significantly decreased at 3 month’s interval who had taken booster dose six to eight months before, consistent across age, gender, infection status, vaccination status, BMI (except normal weight individuals), diabetes, and hypertension. All booster types reduced IgG levels, but the decline with Moderna was insignificant, showing reduction varies depending on the vaccine type