Within-host dynamics of ZIKV-CHIKV co-infection: Stability analysis and effective therapeutic strategies

  • Ahmed Elaiw orcid

    Department of Mathematics, Faculty of Science, King Abdulaziz University, P. O. Box 80203, Jeddah 21589, Saudi Arabia
  • Zainab Alkhudhari

    Department of Mathematics, Faculty of Science, King Abdulaziz University, P. O. Box 80203, Jeddah 21589, Saudi Arabia
  • Aatef Hobiny

    Department of Mathematics, Faculty of Science, King Abdulaziz University, P. O. Box 80203, Jeddah 21589, Saudi Arabia
Article ID: 4021
DOI: https://doi.org/10.59400/adecp4021
Keywords: within-host model; ZIKV-CHIKV co-infection; immune response; antiviral therapy; global stability; basic reproduction number; invasion reproduction number; Lyapunov function

Abstract

In this paper, we develop a mathematical model that describes the within-host co-dynamics of two arboviruses, Zika virus (ZIKV) and Chikungunya virus (CHIKV). The model is also modified to investigate the impact of various treatment strategies. The model incorporates four cell types: uninfected target cells, latently infected cells, actively infected cells, and antibodies. The analysis establishes that all solutions remain nonnegative and bounded over time. It further reveals the presence of four distinct steady states: the disease-free steady state, the ZIKV-only steady state, the CHIKV-only steady state, and the coexistence steady state representing co-infection. The next-generation matrix technique was applied to determine the reproduction numbers for the ZIKV-only model, the CHIKV-only model, and the ZIKV-CHIKV co-infection model (denoted by RZL, RCL and R0L = max{RZL, RCL }, respectively) as well as the invasion reproduction numbers RZL,inv and RCL,inv which determine whether a virus can successfully invade an existing infection state. We conducted a mathematical analysis to determine the existence of equilibrium points and to establish the criteria for their global stability. Global stability is verified through the application of suitably constructed Lyapunov functions. The effects of four therapeutic strategies are included: (i) antiviral therapy that prevents viral infection of target cells, (ii) antiviral therapy that suppresses viral production, (iii) immune-stimulating treatment, and (iv) therapy that increases the rate of antibody circulation. Simulations show antivirals outperform immune-boosting strategies in clearing co-infection, while combining both offers synergy by suppressing replication and enhancing host defenses. The proposed model, along with the theoretical analysis, is new and offers a useful framework for studying viral co-infections.

 

Published
2026-05-06
How to Cite
Elaiw, A., Alkhudhari , Z., & Hobiny, A. (2026). Within-host dynamics of ZIKV-CHIKV co-infection: Stability analysis and effective therapeutic strategies. Advances in Differential Equations and Control Processes, 33(2). https://doi.org/10.59400/adecp4021
Issue
Vol. 33 No. 2 (2026): In Progress
Section
Article

Copyright (c) 2026 Ahmed Elaiw, Zainab Alkhudhari , Aatef Hobiny

Creative Commons License

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

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