The tuberculosis pandemic: implications for health in the tropics

Among infectious diseases, tuberculosis is the leading cause of death, kill ing around 3 million people each year. Most cases occur in young adults but it is also a major cause of illness and death in children. The problem has been exacerbated in recent years by the HIV pandemic and by the emergence of multidrug resistance. Go-infection with HIV greatly enhances the risk of overt tuberculosis and in 1999 it is expected that tuberculosis will accou nt for 30% of the predicted 2.5 million AIDS-related deaths, By inducing cl inically and radiologically atypical forms of tuberculosis, and by increasi ng pressure on diagnostic facilities by sheer numbers, serious diagnostic d ifficulties are increasingly occurring in both adults and children in the t ropics. Ar the present time, 2% of all cases of tuberculosis are multidrug resistant but, as the treatment of such cases is often grossly inadequate i n many tropical countries, their frequency will doubtless grow. There are n o simple solutions to the global emergency of tuberculosis: clearly there i s a need for better use of available control measures but there is also a n eed to reach a much clearer understanding of the underlying immune phenomen a in this disease so as to develop more effective vaccines and therapeutic agents. Finally, it cannot be ignored that tuberculosis is a disease of pov erty-95% of cases and 98% of deaths due to it occur in the developing natio ns-and thus a major control measure is a resolution of the gross inequities in health care provision both between and within nations.