Nasrin Akter, Md. Mejbah Uddin Mithu, Md. Ripon Hossain, et al. The Effects of Preexisting Health Conditions and Vaccination on the COVID-19 Complications. IJSBAR. 2022;64(1):66-80. Accessed September 11, 2025. https://www.gssrr.org/JournalOfBasicAndApplied/article/view/14574