Estimating the number of vertically HIV-infected children eligible for antiretroviral treatment in resource-limited settings

Abstract

Background: With the gradual roll-out of antiretroviral therapy (ART) to delay progression of HIV disease in children in programmes across sub-Saharan Africa and resource-limited settings elsewhere, reliable information on the number of vertically infected children eligible for such treatment is urgently required.

Methods: We present a model to estimate the number of vertically HIV-infected children by age who have progressed to moderate to severe disease (MSD) and as such are eligible for ART on the basis of clinical disease, allowing for: antenatal HIV prevalence, use of interventions to prevent mother-to-child transmission (PMTCT), infant feeding policies and availability of co-trimoxazole to prevent opportunistic infections that may hasten the onset of serious disease. The model assumptions were informed by published evidence and expert opinion; rates of progression to serious disease were inferred from mortality of infected and uninfected children of HIV-infected mothers; and mortality among children treated with ART was based on a study of treated children in Abidjan. To allow widespread use the model has been developed using the Excel spreadsheet software.

Results: With South Africa as a hypothetical example, published antenatal prevalence and demographic data, and assuming PMTCT coverage with single dose nevirapine of 11%, all exposed and infected children receive co-trimoxazole, and various infant feeding policy scenarios, estimated numbers of children eligible for ART are presented.

Conclusions: This model is easy to implement and flexible and can be used in ART programmes at national and local level.