Current trends in chemotherapy of tuberculosis.

After treptomycin, which heralded the era of antibacterial chemotherapy for tuberculosis (TB), many important advances have made available treatment regimens that are almost 100 per cent curative. Randomised clinical trials by the Tuberculosis Research Centre, in Chennai and British Medical Research Council in East Africa and in the Far East have helped to establish many of the principles of antituberculosis chemotherapy. With successes have also come fresh challenges. Mycobacterium tuberculosis becomes rapidly resistant to the drugs used against it and in the last decade, the HIV epidemic has had an adverse impact on the global epidemiology of tuberculosis, with many countries in Sub-Saharan Africa experiencing a 2-3 fold increase in their TB burden. While the currently recommended treatment regimens are very effective, they have failed to control the burden of TB in the developing countries due to less than satisfactory implementation of the control programmes. Faced with the dual threat of multidrug resistant TB and the HIV/facilitated increase in TB, the WHO has instituted a Global TB Control Programme based on the directly observed treatment shortcourse (DOTS) strategy. Much of the principles of this strategy have come out of research in India. As part of this strategy, the Government of India is implementing a Revised National Tuberculosis Control Programme (RNTCP). Under the RNTCP standardized treatment regimens are prescribed for different treatment categories. Already more than 80 per cent of the population is covered by this Programme and full coverage is slated for 2005. Meanwhile, fresh research is ongoing to shorten treatment duration, a measure that should greatly aid TB control.