The Estimation and Projection Package Age-Sex Model and the r-hybrid model: New tools for estimating HIV incidence trends in sub-Saharan Africa

Jeffrey W. Eaton, Tim Brown, Robert Puckett, Robert Glaubius, Kennedy Mutai, Le Bao, Joshua A. Salomon, John Stover, Mary Mahy, Timothy B. Hallett

Research output: Contribution to journalArticle

4 Scopus citations

Abstract

Objectives:Improve models for estimating HIV epidemic trends in sub-Saharan Africa (SSA).Design:Mathematical epidemic model fit to national HIV survey and ANC sentinel surveillance (ANC-SS) data.Methods:We modified EPP to incorporate age and sex stratification (EPP-ASM) to more accurately capture the shifting demographics of maturing HIV epidemics. Secondly, we developed a new functional form for the HIV transmission rate, termed 'r-hybrid', which combines a four-parameter logistic function for the initial epidemic growth, peak, and decline followed by a first-order random walk for recent trends after epidemic stabilization. We fitted the r-hybrid model along with previously developed r-spline and r-trend models to HIV prevalence data from household surveys and ANC-SS in 177 regions in 34 SSA countries. We used leave-one-out cross validation with household survey HIV prevalence to compare model predictions.Results:The r-hybrid and r-spline models typically provided similar HIV prevalence trends, but sometimes qualitatively different assessments of recent incidence trends because of different structural assumptions about the HIV transmission rate. The r-hybrid model had the lowest average continuous ranked probability score, indicating the best model predictions. Coverage of 95% posterior predictive intervals was 91.5% for the r-hybrid model, versus 87.2 and 85.5% for r-spline and r-trend, respectively.Conclusion:The EPP-ASM and r-hybrid models improve consistency of EPP and Spectrum, improve the epidemiological assumptions underpinning recent HIV incidence estimates, and improve estimates and short-term projections of HIV prevalence trends. Countries that use general population survey and ANC-SS data to estimate HIV epidemic trends should consider using these tools.

Original languageEnglish (US)
Pages (from-to)S235-S244
JournalAIDS
Volume33
DOIs
StatePublished - Dec 15 2019

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All Science Journal Classification (ASJC) codes

  • Immunology and Allergy
  • Immunology
  • Infectious Diseases

Cite this

Eaton, J. W., Brown, T., Puckett, R., Glaubius, R., Mutai, K., Bao, L., Salomon, J. A., Stover, J., Mahy, M., & Hallett, T. B. (2019). The Estimation and Projection Package Age-Sex Model and the r-hybrid model: New tools for estimating HIV incidence trends in sub-Saharan Africa. AIDS, 33, S235-S244. https://doi.org/10.1097/QAD.0000000000002437