Modeling the Transmission Dynamics of the Monkeypox Virus Infection with Treatment and Vaccination Interventions

Presently, an ongoing outbreak of the monkeypox virus infection that began in Bayelsa State of Nigeria has now spread to other parts of the country including mostly States in the South-South with the Nigerian Ministry of Health confirming 4 samples out of the 43 sent for testing at WHO Regional Laboratory in Dakar, Senegal. This reminds us that apart from the eradicated smallpox, there are other poxviruses that pose potential threat to people in West and Central Africa. In this paper, we developed a mathematical model for the dynamics of the transmission of monkeypox virus infection with control strategies of combined vaccine and treatment interventions. Using standard approaches, we established two equilibria for the model namely: disease-free and endemic. The disease-free equilibrium was proved to be both locally and globally asymptotically stable if R₀ < 1 using the next-generation matrix and the comparison theorem. While the endemic equilibrium point existed only when R₀ > 1, was proved to be locally asymptotically stable if R₀ > 1 using the linearization plus row-reduction method. The basic reproduction numbers for the humans and the non-human primates of the model are computed using parameter values to be R_0,h = 9.1304 x 10^-6 and R_0,n = 3.375 x 10^-3 respectively. Numerical simulations carried out on the model revealed that the infectious individuals in the human and non-human primates’ populations will die out in the course of the proposed interventions in this paper during the time of the study. Sensitivity analysis carried out on the model parameters shows that the basic reproduction numbers of the model which served as a threshold for measuring new infections in the host populations decrease with increase in the control parameters of vaccination and treatment.