MATHEMATICAL ASSESSMENT OF THE IMPACT OF TREATMENT AND VACCINATION ON THE TRANSMISSION DYNAMICS OF TYPHOID FEVER

Typhoid fever is a life threatening illness and its outbreaks remains a challenge. In this study, we incorporate treatment in the dynamics of the disease. The existence and stability of the disease-free-equilibrium state (DFEs) of the modified model is studied using linearization approach. The result of the study showed that a DFE exits, and is locally asymptotically stable. The threshold parameter ????0,the reproduction number that governs the disease transmission was computed by the next generation operator approach from which we performed sensitivity analysis in order to determine the relative importance of the modified model parameters on the disease transmission. The dynamics of the model is also investigated numerically using published data. Results obtained show that if the rate of carriers is not high, treatment is an effective way of eradicating typhoid disease.