Childhood tuberculosis - global epidemiology and the impact of HIV.

The burden of tuberculosis (TB), worldwide, is influenced by the human immunodeficiency virus (HIV) epidemic. Between 1990 and 2004, the tuberculosis incidence stabilised or fell steadily in most parts of the world, with the exception of Africa. HIV and HIV-associated TB affects young adults, which may result in increased rates of TB transmission to children. Moreover, HIV-infected children are at increased risk of TB and of more severe forms of TB compared with immunocompetent children. There is evidence that TB is more common in children living in households affected by HIV. Owing to the higher mortality during and after TB treatment, the outcome of TB is also worse among HIV-infected children, with lower cure and higher recurrence rates. Although available reports still show low levels of drug resistance among children, continued surveillance will be important to detect any increase in resistance rates, including multidrug-resistant TB. As BCG is still the only vaccine available, research needs to be focused on better methods of preventing TB. Furthermore, the development of better diagnostics for infection and disease will improve the management of TB in children.