Abstract. 

In 1969, two missionary nurses died due to Lassa fever infection, which led to the identification of the Lassa virus (LASV) in Nigeria. Infections from the Lassa virus are about 80% asymptomatic, but severe cases normally result in multi-organ failure or death. This accounts for about 15% of the hospitalized cases. Different scientific strategies to eradicate the disease have yielded minimal results. In this study, a mathematical model to study the transmission dynamics of Lassa fever is formulated and analyzed. The model has five compartments. The human population is compartmentalized into three sub-populations, while the rodent population is compartmentalized into two sub-populations. The model has two equilibrium states, namely, the disease-free equilibrium (DFE) and the disease endemic equilibrium (DEE). The stability analysis of the DFE revealed that it is locally asymptotically stable when the basic reproduction number (R0) is less than one and unstable otherwise. The sensitivity analysis on the model reproduction number revealed that the infection transmission rates from human-to-human, rodent-to-human, and from human-to-rodent are the causes of the disease persistence in the human population. The Hopf-bifurcation analysis of the model using the transmission rate from both rodents and humans to humans as the bifurcation parameter shows the stability point of the model at αh = 0.025. The numerical analysis result perfectly aligns with the model’s qualitative results obtained.