Sensitivity Analysis of a Mathematical Model for Tuberculosis-Schistosomiasis Model with Vaccination and Treatment
Abstract
Herein, we investigate the uncertainty and sensitivity analysis of the effective reproduction number belonging to a tuberculosis-schistosomiasis co-infection model which harbours both vaccination and treatment as espoused by Ako and Omoregie [3]. The results gleaned from some of the contour plots showed that the impact of the treatment levels for individuals with infectious TB on the burden of tuberculosis in a population, is largely determined by the efficacy of the BCG vaccine on vaccinated individuals. Furthermore, just as obtained in Ako [1], the impact of the fraction of individuals who progress to infectious TB via the fast route is also determined by the proportion of individuals unvaccinated with the BCG vaccine. Furthermore, contour plots suggest that the effect of the cercarial production, cercarial penetration, the number of schistosome eggs secreted and the successful conversion of the eggs to miracidia, on the hardship of tuberculosis in a populace, is predominantly determined by the medical care levels for individuals with active schistosomiasis. Hence, public health policy should take into account the level of medical care facilities available. With increasing (and sustained) treatment rates for schistosomiasis infections, having a large proportion of active schistosomiasis patients expeditiously receiving medical care will result in a reduction in the disease hardship in the populace.
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