MODELLING THE IMPACT OF BCG VACCINES ON TUBERCULOSIS EPIDEMICS

摘要

Abstract In this paper, we study vaccination by a tuberculosis (TB) dynamics model incorporating treatment, migration and vaccination. We formulate theorem on existence and uniqueness of solution in order to ascertain the existence of our model. Using a stability analysis of the disease-free equilibrium (DFE) and the basic reproduction number , an analytic threshold which dictates when BCG vaccination will increase the stability of the DFE was established. The analysis found that mass vaccination by BCG is advantageous in countries with a high TB burden in order to result in a more stable DFE for disease elimination.