ABSTRACT
It is currently estimated that 95% of cases of tuberculosis and 98% of deaths due to tuberculosis worldwide occur in the developing world annually (1). The evolution of the global tuberculosis epidemic is therefore dependent on the tuberculosis-control strategies that are applied in developing countries and on their ability to respond to the needs of the most vulnerable sections of the population in each country during the next 20 years. It seems clear that in the year 2020 tuberculosis will still be, as it is today, seventh on the list of diseases principally responsible for the burden of mortality worldwide, and that during 2000-2020 the gap between rich and poor countries will only increase (2). As a result, a careful evaluation of the tuberculosis control strategies that are applied is of crucial importance, in order both to adopt the most efficient methods of containing, and then reducing, tuberculosis, and to measure the impact of these strategies.
