Abstract

While young adults are generally considered resilient, the longterm side effects of COVID-19 vaccines in this demographic remain largely unexplored. This study investigates post-vaccination experiences among university students and faculty collected from three universities in Sylhet, Bangladesh through online and offline surveys between January and March 2025. After rigorous data cleaning, a finalized dataset of 591 respondents was obtained covering vaccine type, dosage, demographics, pre-existing health conditions, overseas travel history, and post-vaccination impacts (short-term, medium-term, and long-term). Descriptive, correlation, and predictive analyses were performed. Five supervised machine learning (ML) classifiers - Logistic Regression (LR), Random Forest (RF), Support Vector Machine (SVM), XGBoost, and K-Nearest Neighbors (KNN) - were evaluated alongside K-Means clustering (k = 4) with Principal Component Analysis (PCA) for patient risk profiling. Logistic Regression achieved the highest accuracy (70.79%). Random Forest feature importance identified side-effect severity (52.8%) and vaccine type (34.7%) as the dominant predictors. Respiratory conditions and allergies were the leading comorbidities associated with post-vaccination impacts. Findings provide actionable insights for policymakers and healthcare professionals refining vaccination protocols for young, active populations.

References

• F. P. Polack, S. J. Thomas, N. Kitchin, J. Absalon, A. Gurtman, S. Lockhart, J. L. Perez, et al., “Safety and efficacy of the BNT162b2 mRNA Covid-19 vaccine,” New England Journal of Medicine, vol. 383, no. 27, pp. 2603–2615, 2020.
• L. R. Baden, H. M. El Sahly, B. Essink, K. Kotloff, S. Frey, R. Novak, D. Diemert, et al., “Efficacy and safety of the mRNA-1273 SARS-CoV-2 vaccine,” New England Journal of Medicine, vol. 384, no. 5, pp. 403–416, 2021.
• A. Jones, J. Smith, and E. Brown, “Lifestyle factors and COVID-19 vaccine side effects among university students,” Journal of Adolescent Health, vol. 70, no. 3, pp. 456–462, 2022.
• J. Chapin-Bardales, J. Gee, and T. Myers, “Reactogenicity following receipt of mRNA-based COVID-19 vaccines,” JAMA, vol. 325, no. 21, pp. 2201–2202, 2021.
• J. Gee, P. Marquez, J. Su, G. M. Calvert, R. Liu, T. Myers, N. Nair, S. Martin, T. Clark, L. Markowitz, et al., “First month of COVID-19 vaccine safety monitoring - United States, December 14, 2020–January 13, 2021,” Morbidity and Mortality Weekly Report (MMWR), vol. 70, no. 8, pp. 283–288, 2021.
• C. Menni, K. Klaser, A. May, L. Polidori, J. Capdevila, P. Louca, C. H. Sudre, L. H. Nguyen, D. A. Drew, J. Merino, et al., “Vaccine side-effects and SARS-CoV-2 infection after vaccination in users of the COVID symptom study app in the UK: a prospective observational study,” The Lancet Infectious Diseases, vol. 21, no. 7, pp. 939–949, 2021.
• M. S. Rahman, M. T. Islam, and M. Z. Hossain, “COVID- 19 vaccination in Bangladesh: challenges and opportunities,” Journal of Global Health, vol. 11, pp. 1–8, 2021.
• M. T. Islam, M. S. Rahman, and M. Z. Hossain, “Short-term side effects of COVID-19 vaccines in Bangladesh: a crosssectional study,” Bangladesh Medical Research Council Bulletin, vol. 48, no. 1, pp. 45–52, 2022.
• M. J. Alam, M. A. Khan, and M. S. Rahman, “Preexisting conditions and COVID-19 vaccine side effects in Bangladesh,” Journal of Health, Population and Nutrition, vol. 41, no. 1, pp. 1–10, 2022.
• M. A. Khan, M. J. Alam, and M. S. Rahman, “Vaccine hesitancy among university students in Bangladesh: a crosssectional study,” BMC Public Health, vol. 22, no. 1, pp. 1–9, 2022.
• H. G. Rosenblum, S. C. Hadler, D. Moulia, T. T. Shimabukuro, J. R. Su, N. K. Tepper, et al., “Safety of mRNA vaccines administered during the initial 6 months of the US COVID-19 vaccination programme: an observational study,” The Lancet, vol. 399, no. 10325, pp. 924–944, 2022.
• D. K. Shay, J. Gee, J. R. Su, T. R. Myers, P. Marquez, R. Liu, B. Zhang, C. Licata, T. A. Clark, and T. T. Shimabukuro, “Safety monitoring of the Janssen (Johnson & Johnson) COVID-19 vaccine - United States, March–April 2021,” Morbidity and Mortality Weekly Report (MMWR), vol. 70, no. 18, pp. 680–684, 2021.
• J. Smith, E. Brown, and A. Jones, “Vaccine hesitancy among university students: a global perspective,” Vaccine, vol. 39, no. 45, pp. 6543–6549, 2021.
• M. Z. Hossain, M. S. Rahman, and M. T. Islam, “Factors influencing COVID-19 vaccine acceptance in Bangladesh: a cross-sectional study,” Vaccine, vol. 39, no. 45, pp. 6543– 6549, 2021.
• S. S. A. Karim and T. de Oliveira, “Challenges and opportunities for COVID-19 vaccination in low- and middle-income countries,” The Lancet Global Health, vol. 9, no. 6, pp. e789– e790, 2021.