Dealing with the dual epidemics of HIV and TB

This article summarises three of the presentations made at a TB symposium at the recent 2nd South African AIDS Conference in Durban. HIV infection is the most potent risk factor for active tuberculosis (TB) and and as a result TB has become the leading life-threatening opportunistic infection. In addition it has changed the epidemiology of TB in high HIV prevalence, settings; HIV makes the diagnosis of TB more difficult and is associated with a far higher risk of death. Preventive treatment regimens in HIV-infected adults have been shown to be efficacious and cost effective but their widespread implementation is hampered by poor adherence, concerns about development of resistance and the potential burden to the TB control programme. Result of adult cohort studies suggest that antiretroviral treatment has a powerful preventive effect on active TB; however, successful ARV treatment does not restore immune function and TB risk to levels seen in HIV-uninfected adults. Novel strategies are therefore urgently needed to combat TB in high HIV prevalence settings.