This paper presents a dual-strain SEIR epidemic model designed to capture the transmission dynamics of the Central and West African clades of monkeypox. The model incorporates four non-monotonic transmission processes to reflect the complexity of the disease’s spread within each clade. We identify two distinct reproduction thresholds, \(R_{0,1}\) and \(R_{0,2}\) , which correspond to the basic reproduction numbers of the respective clades. By analyzing the local and global stability of the system, we establish the conditions under which the disease-free equilibrium remains stable or transitions into an endemic state. Furthermore, we explore the occurrence of forward bifurcation when \(R_0 = 1\) , highlighting the critical points where the disease shifts from containment to widespread transmission. A comprehensive sensitivity analysis reveals the key factors influencing the spread, including the rate at which susceptible individuals are introduced, the interactions between susceptible and exposed populations, and the duration of incubation periods. Numerical simulations validate our theoretical findings and demonstrate the model’s relevance to real-world scenarios. The results provide valuable insights into the control strategies needed to manage monkeypox outbreaks and underscore the significance of understanding clade-specific transmission dynamics for effective intervention planning.
