Molecular and geographic patterns of tuberculosis transmission after 15 years of directly observed therapy.

Open Access
Publisher Website
Google Scholar
Abstract
THE RECENT resurgence of tuberculosis in the United States has focused attention on the dynamics of tuberculosis control. The incidence of tuberculosis in a community is a function of both the rate at which latent Mycobacterium tuberculosis infections are reactivated and the number of case contacts who develop primary tuberculosis.1 The application of molecular typing of M tuberculosis isolates2 to epidemiologic evaluation of tuberculosis has shown that 35% to 50% of tuberculosis cases in urban areas in the United States occur in clusters that share matching restriction fragment length polymorphism (RFLP) types, suggestive of recent transmission.3-5 An alternative hypothesis is that certain RFLP types are endemic within a region during long periods and that remote transmission of such strains with a period of latent disease prior to reactivation could result in matching types among long-standing residents of the area.6