Mathematical modelling and optimal-control strategies of schistosomiasis–typhoid fever co-infection: using the demographic setting of Makurdi, Benue State, Nigeria

Authors

  • Kazeem A. Tijani
    Department of Mathematics, Joseph Sarwuan Tarka University, formerly Federal University of Agriculture, Makurdi, Benue State, Nigeria
  • Chinwendu E. Madubueze
    Department of Mathematics, Joseph Sarwuan Tarka University, formerly Federal University of Agriculture, Makurdi, Benue State, Nigeria
  • Reuben I. Gweryina
    Department of Mathematics, Joseph Sarwuan Tarka University, formerly Federal University of Agriculture, Makurdi, Benue State, Nigeria
  • Terhemen Aboiyar
    Department of Mathematics, Joseph Sarwuan Tarka University, formerly Federal University of Agriculture, Makurdi, Benue State, Nigeria

Keywords:

Co-infection, Mathematical model, Schistosomiasis-Typhoid fever, Optimal control

Abstract

Co-infection of schistosomiasis and typhoid fever presents a significant public-health challenge and complicates clinical management. Both diseases are prevalent and endemic in African regions, particularly Nigeria, but their co-dynamics remain insufficiently studied. This study developed a deterministic mathematical model to examine the co-dynamics of schistosomiasis and typhoid fever in Makurdi, Benue State, Nigeria. The basic reproduction number (R0) for the sub-models and the full co-infection model was calculated to assess the stability of the disease-free equilibrium and to conduct bifurcation analysis. The endemic equilibrium was derived. Global sensitivity analysis was conducted, and an optimal-control model was formulated with five time-dependent controls: prevention of schistosomiasis, prevention of typhoid fever, screening and treatment for schistosomiasis, screening and treatment for typhoid fever, and screening and treatment for co-infections. The model was analysed using the Pontryagin maximum principle and the forward--backward sweep method. Numerical simulations included single, pairwise, and combined interventions. The results indicate that prevention strategies for both diseases are more effective than treatment alone. The study recommends implementing concurrent control interventions for both diseases to achieve optimal co-infection management.

Dimensions

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Published

2026-06-22

How to Cite

Mathematical modelling and optimal-control strategies of schistosomiasis–typhoid fever co-infection: using the demographic setting of Makurdi, Benue State, Nigeria. (2026). Journal of the Nigerian Society of Physical Sciences, 8(3), 3376. https://doi.org/10.46481/jnsps.2026.3376

Issue

Volume 8, Issue 3, August 2026 (In Progress)

Section

Mathematics & Statistics
Copyright & Licensing

Copyright (c) 2026 Kazeem A. Tijani, Chinwendu E. Madubueze, Reuben I. Gweryina, Terhemen Aboiyar (Author)

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

Mathematical modelling and optimal-control strategies of schistosomiasis–typhoid fever co-infection: using the demographic setting of Makurdi, Benue State, Nigeria. (2026). Journal of the Nigerian Society of Physical Sciences, 8(3), 3376. https://doi.org/10.46481/jnsps.2026.3376

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