HIV/AIDS is a leading cause of morbidity and mortality among children and adolescents, and it is well recognized that HIV care and treatment among children (birth to 9 years) and young adolescents (10-14 years) lags behind that of adults, leading to numerous calls to action. Despite a global consensus toward eliminating new HIV infections in these age groups, assessing progress against targets is impeded, as current estimates do not include substantial amounts of locally-available data. Additionally, new HIV infections in young adolescents have not been quantified. The global HIV burden in these age groups is currently estimated by two groups: the Global Burden of Disease (GBD) study and UNAIDS, both of which currently assume no new HIV infections for those under 15. Both groups use the Spectrum child model, which relies largely on estimated HIV prevalence among adult women, treatment for prevention of mother-to-child transmission, and other assumptions to estimate the HIV burden among children and young adolescents. One of the assumptions is that new HIV infections among those under 15 come from only one source ? mother-to-child transmission ? assuming no sexual activity and zero HIV incidence in young adolescents. In addition to behavioral factors, evidence shows that the risk of HIV transmission is influenced by biomedical factors (e.g., HIV testing rates, antiretroviral therapy coverage) and structural factors (e.g., national wealth, access to education, health care quality and access). However, there has been no systematic study of the impact of these factors on the trajectory of the HIV epidemic. Given the complexity of the epidemic and the interplay of contributing factors, additional data and analyses are needed to understand the relative impact of these factors. Developing methods to triangulate newly acquired data sources is crucial to enhancing understanding of the drivers of the epidemic, and to generating more robust HIV burden estimates for children and adolescents. Accordingly, the goal of this study is to address the limitations of existing methods by triangulating empirical data sources to produce more accurate and comprehensive estimates of pediatric HIV burden, including an understanding of how biomedical, behavioral, and structural factors impact the burden among children and adolescents. Our proposal advances beyond existing work by providing the first- ever estimates of new HIV infections among young adolescents, and by incorporating these results into an interactive visualization platform to help key stakeholders understand the current and projected future burden of HIV/AIDS among children and adolescents under different scenarios. This project is comprised of four Specific Aims: (1) Incorporate currently unused data sources to estimate mother-to-child transmission and HIV burden among children (0-9 years); (2) Estimate new infections among young adolescents (10-14 years); (3) Quantify the impact of biomedical, behavioral, and structural factors on HIV transmission probabilities and mortality among children and young adolescents; and (4) Forecast future burden of HIV among children and adolescents through 2040 based on current trends in incidence, prevalence, and mortality, and exposure to risk and protective factors.
HIV/AIDS is a leading cause of morbidity and mortality among children and adolescents, and robust estimates of the HIV burden among these age groups are needed to inform intervention priorities and monitor progress toward global targets. The goal of this study is to address limitations of existing methods by triangulating empirical data sources to produce more accurate and comprehensive estimates of pediatric HIV burden than current statistics, including the first-ever global estimates of new HIV infections among young adolescents, as well as insight into the unique contributions of biomedical, behavioral, and structural factors on the burden of HIV/AIDS in children and young adolescents. We will do so by assembling and triangulating data sources; quantifying the relationship between risk and protective factors and child/adolescent HIV burden; and forecasting the future burden of HIV among children/adolescents through 2040 based on current trends in incidence, prevalence, and mortality, and exposure to risk and protective factors.