The impact of antiretroviral treatment on the burden of invasive pneumococcal disease in South African children: a time series analysis.

OBJECTIVE: HIV infection is a major risk factor for invasive pneumococcal disease (IPD). A national antiretroviral program was initiated in South Africa in 2004. This study evaluates the impact of the highly active antiretroviral therapy (HAART) treatment program on the burden of IPD among African children.
DESIGN: Retrospective analysis of laboratory-confirmed IPD among children under 18 years of age, from 2003 to 2008.
METHODS: The periods 2003-2004, 2005-2006 and 2007-2008 were defined as the early, intermediate and established HAART eras, respectively. Pneumococcal conjugate vaccine was not introduced into public immunization during this period.
RESULTS: One thousand, one hundred and seventy-one episodes of IPD were identified over the study period. Among HIV-infected children under 18 years, the burden of IPD decreased by 50.8% [95% confidence interval (CI) 41.5-58.7] and the incidence of IPD-related mortality declined by 65.2% (95% CI 47.2-77.0) from the early compared to the established HAART era. This decline in HIV-infected children was evident for pneumococcal bacteremia and pneumococcal meningitis. In addition, similar reductions were observed for serotypes included in a 7-valent pneumococcal conjugate vaccine and nonvaccine serotypes. The burden of IPD remained unchanged in HIV-uninfected children under 18 years of age over these periods. The risk of IPD, however, remained 42-fold greater in HIV-infected compared to HIV-uninfected children in the established HAART era.
CONCLUSIONS: Although the HAART program has been associated with significant declines in IPD morbidity and mortality, HIV-infected African children with access to HAART remain a high-risk group for IPD. These children should therefore be prioritized in the prevention of IPD.