Assessment of worldwide tuberculosis control

Background. Because worldwide tuberculosis (TB) control had never been assessed, WHO set up a surveillance and monitoring project in 1995. The objectives were to assess the performance of national TB programmes; to assess the extent of implementation of the WHO strategy of TB control; and to attempt a comparison between regions that had adopted the WHO strategy and those that had not. Methods. In June, 1996, we sent data-collection forms requesting information on national TB programmes' control policies, 1995 case notifications, and 1994 treatment results to 216 countries, areas, and territories. We assessed the performance of national TB programmes by comparing case notifications with estimated incidence and by outcome of treatment in cohorts of patients. We also investigated worldwide treatment success and case detection among sputum-smear-positive patients. Findings. 180 (83%) of the 216 countries, areas, and territories surveyed replied to WHO (98% of the worldwide population). In 1995, the WHO control strategy had been implemented in 75 countries, and in 39 of these implementation was countrywide. Up to 23% of the worldwide population lived in regions where the strategy was available. In 1995, 3 297 688 cases of TB (all types) were reported, of which 1161411 (35%) were sputum-smear positive. 54% of all reported cases in countries that used the WHO strategy were sputum-smear positive, compared with 30% in other countries. The worldwide case-detection rate of new sputum-smear positive cases was 35%, 92% of cases registered for treatment in 1994 in regions that used WHO strategy were assessed for outcome and 76% were treated successfully, compared with 54% and 42%, respectively, in regions that had not implemented the WHO strategy. Among cases reported worldwide in 1994, the documented treatment-success rate was 43%, Interpretation National TB programmes that have adopted the WHO TB control strategy achieve higher cure rates, but their impact on TB is modest on a worldwide scale. Wider continuous coverage with the WHO strategy is needed for effective worldwide TB control.