Can we control tuberculosis in high HIV prevalence settings?

The overlap between the epidemiology of HIV and tuberculosis and consequent rapid rise in numbers of patients with tuberculosis in many African countries has put a huge burden on health systems. The stigma of HIV has increased the existing stigma surrounding tuberculosis. There are three mechanisms by which we may reduce the number of cases of tuberculosis in a community: reducing transmission of tuberculosis, reducing reactivation of latent tuberculosis infection and reducing HIV transmission. Reinforcing the existing health service to find more cases, active case-finding in communities or enhanced case-finding in specific groups will reduce transmission of tuberculosis. However, health services that find it difficult to find cases efficiently will also find it difficult to support patients throughout treatment to achieve a cure. Partnership with traditional healers, community-based organizations and private practitioners could reduce this burden. Reactivation of tuberculosis among people living with HIV can be reduced by tuberculosis preventive therapy or by antiretroviral therapy. Programmes that identify people living with HIV can also implement enhanced tuberculosis case-finding increasing the benefits of the programme. However, the impact of widespread use of antiretroviral therapy may be to increase the number of people in a community who are mildly immunocompromised and the incidence of tuberculosis at a community level might rise. Any strategy that successfully reduces HIV transmission will benefit tuberculosis control, since around a third of all HIV-positive individuals will develop tuberculosis before they die. To control tuberculosis in high HIV prevalence settings, we must strengthen health systems to include not only expansion of the DOTS strategy but also full-blooded implementation of voluntary counselling and testing, enhanced and active tuberculosis case-finding, preventive therapy and better care for people living with HIV including antiretroviral therapy. The approach needed to control tuberculosis needs also to be integrated into broader development and poverty reduction goals.