In this study, a deterministic co-infection model of dengue virus and malaria fever is proposed. The disease free equilibrium point (DFEP) and the Basic Reproduction Number is derived using the next generation matrix method. Local and global stability of DFEP is analyzed. The result show that the DFEP is locally stable if R0dm < 1 but may not be asymptotically stable. The value of R0dm calculated is 19.70 greater than unity; this implies that dengue virus and malaria fever are endemic in the region. To identify the dominant parameter for the spread and control of the diseases and their co-infection, sensitivity analysis is investigated. From the numerical simulation, increase in the rate of recovery for co-infected individual contributes greatly in reducing dengue and malaria infections in the region. Decreasing either dengue or malaria contact rate also play a significant role in controlling the co-infection of dengue and malaria in the population. Therefore, the center for disease control and policy makers are expected to set out preventive measures in reducing the spread of both diseases and increase the approach of recovery for the co-infected individuals.

Mathematical models has been useful over the years to understand the behavior and impacts of several infectious diseases such as Malaria, Ebola, Cholera, in human and non-human population. In this paper, a modified mathematical model of covid-19 virus in Nigeria is presented. The disease free equilibrium, endemic equilibrium state, threshold behavior 𝑅0 and the bounded region where the model is mathematically and epidemiologically feasible is established. The global stability analysis for the disease-free and endemic equilibria are obtained using Carlos Chavez theorem and LaSalle’s criterion. The results show that the virus will cause devastating impacts (𝑅𝑜>1) in Nigeria if the control and mitigation mechanisms are not adhered to. The numerical approximations of the model via differential transform method illustrate the impacts of the virus dynamical transmission in time/per week. The approximation’s insight raises concern as more people will be susceptible and exposed to the virus, the number of infectious individuals will be on the increase for some time with more hospitalize-isolation individuals in Nigeria. The approximation also shows an increasing rate of recovery for infected individuals.