Epidemiology of AIDS and tuberculosis

ABSTRACT

This article reviews literature on the epidemiology, pathogenicity, and control of HIV and Micobacterium tuberculosis coinfection. Regarding pathogenicity, immune system deterioration makes HIV-infected people more likely to develop active tuberculosis on primary or secondary exposure to the bacillus or to suffer reactivation of latent infections, and to experience considerably higher rates of extrapulmonary manifestations, relapses, and death. Regarding epidemiology, as of 1990 there were an estimated 3 million people coinfected with HIV and M. tuberculosis, with some 300 000 active tuberculosis cases and 120 000-150 000 tuberculosis deaths occurring annually among those coinfected. Over 500 000 coinfected people are thought to reside in the Americas, over 400 000 of them in Latin America. In general, the impact of coinfection is evident. Relatively high and increasing prevalences of HIV infection have been detected among tuberculosis patients around the world, and tuberculosis has become a frequent complication of AIDS cases. Moreover, there is no longer any doubt that coinfection obstructs tuberculosis prevention and control. Among other things, it effects BCG vaccination policies, suggests the need to administer preventive chemoprophylaxis to HIV-infected individuals at high risk of harboring or contracting tuberculosis infections, and complicates both detection and treatment of active tuberculosis cases. The recent proliferation of M. tuberculosis strains resistant to multiple drugs, most notably in the United States, compounds the problem... (AU)