Abstract: We have examined the effect of vaccination, treatment and population area size on the transmission dynamics of tuberculosis, in a proportionate mixing population with vital dynamics, where the vaccine is assumed to be leaking, so that vaccinated individuals progress to the infectives population, when in contact with the disease. Three subs-models for the transmission dynamics of the disease are proposed and the influence of the population area size on each are examined via the basic reproductive number of the disease and the determinant, trace stability conditions. The non trivial equilibrium states are obtained and their stability discussed.