Survival from 9 months of age among HIV-infected and uninfected Zambian children prior to the availability of antiretroviral therapy

Background. Few prospective studies have measured survival rates among human immunodeficiency virus (HIV)-infected children in sub-Saharan Africa prior to the availability of antiretroviral therapy. Methods. In the context of an observational study of the immunogenicity of measles vaccine in Zambia, we prospectively followed up children from approximately 9 months of age and assessed survival rates, risk factors for mortality, and circumstances at the time of death according to HIV-infection or HIV-exposure status. Results. There were 56 deaths among 492 study children during follow-up to 3 years of age. Thirty-nine percent of the 105 children with HIV infection died during the study period, compared with 5.0% of the 260 HIV-seropositive but uninfected children and 1.6% of the 127 HIV-seronegative children. Estimated survival probabilities from 9 through 36 months of age were 52% among HIV-infected children, 95% among initially HIV-seropositive but uninfected children, and 98% among HIV-seronegative children. In multivariable analyses, history of a clinic visit within the 4 weeks prior to study entry (adjusted hazard ratio, 4.6; 95% confidence interval, 1.5-13.5), hemoglobin level <8 g/dL at study entry (adjusted hazard ratio, 4.4; 95% confidence interval, 1.5-12.6), land CD4(+) T lymphocyte percentage <15% at study entry (adjusted hazard ratio, 3.2; 95% confidence interval, 1.1-9.5) were associated with mortality among HIV-infected children. Conclusions. Only approximately one-half of HIV-infected Zambian children who were alive at 9 months of age survived to 3 years of age, supporting the urgent need for the prevention of mother-to-child transmission of HIV and the early diagnosis and treatment of HIV infection in children in sub-Saharan Africa.