Progression to active tuberculosis, but not transmission, varies by Mycobacterium tuberculosis lineage in The Gambia.

Background: There is considerable variability in the outcome of Mycobacterium tuberculosis infection. We hypothesized that Mycobacterium africanum was less likely than M. tuberculosis to transmit and progress to tuberculosis disease.

Incidence of tuberculosis and the predictive value of ELISPOT and Mantoux tests in Gambian case contacts.

Background: Studies of Tuberculosis (TB) case contacts are increasingly being utilised for understanding the relationship between M. tuberculosis and the human host and for assessing new interventions and diagnostic tests. We aimed to identify the incidence rate of new TB cases among TB contacts and to relate this to their initial Mantoux and ELISPOT test results.