Additional file 1: Figure 1. Active TB was defined by clinical signs and symptoms of pulmonary disease consistent with active tuberculosis and a chestradiograph prior to treatment consistent with active pulmonary TB. Among such patients, a sputum sample was evaluated for the presence of M. tuberculosisby either Ziehl–Neelsenstaining (bacilloscopy) or outgrowth from culture in Lowenstein-Jensenmedium (culture). Per cent positive among HIV-negative and HIC-positive TB patients is shown.