A Coinfection Model of Bacterial Meningitis and Hepatitis B Diseases With Optimal Control and Cost-Effectiveness Analysis. - Malede Atnaw Belay; Jeconia Abonyo Okelo; David Mwangi Theuri; Haileyesus Tessema Alemneh; Negesse Yizengaw Alemu (J. Appl. Math., 2025)