In spite of a massive effort to apply the tools currently available for tuberculosis (TB) control, both in this country and abroad, it is clear that complicating factors [for example, HIV co-infection, drug resistance, lack of patient compliance with chemotherapy, variable efficacy of Bacille Calmette-Guerin (BCG) vaccine] will prevent disease control unless new drugs, vaccines and diagnostic tests are developed (1). The publication of the complete genome sequence of Mycobacterium tuberculosis in 1998 (2) has facilitated a directed search for virulence genes, new drug targets, and vaccine antigens. This research effort has been made possible by the availability of highly biologically relevant animal models of pulmonary TB ((3)).