EPIDEMIOLOGY OF TUBERCULOSIS IN THE WORLD

Tuberculosis is the most important single cause of infectious disease in the world today, causing 8 million new cases and 3 million deaths a nnually. Almost one third of the world's population is infected with t he causative organism, Mycobacterium tuberculosis, The declining trend in cases ceased or reversed in the developed and parts of the develop ing world during the 1980s. In most developing countries, especially i n Africa and Asia, the trend continues to deteriorate due to failure t o give priority to, or poorly organized, programs with low case findin g and cure, lack of international donors support, coinfection with the human immunodeficiency virus (HIV), increasing homelessness, and incr easing institutional outbreaks. Although modern short course combinati on chemotherapy is highly effective, mortality rates remain high in th ese areas. Drug resistance, particularly resistance to isoniazid and r ifampin (MDR-TB), poses a significant problem to control programs but with some exceptions has not been surveyed systematically; the WHO/IUA TLD Global Surveillance Project was established to address this defici ency and its role is as described.