Sex Transm Infect 88:i65-i75 doi:10.1136/sextrans-2012-050789
  • Supplement

Trends in HIV prevalence among young people in generalised epidemics: implications for monitoring the HIV epidemic

Open Access
  1. Kimberly Anne Marsh3
  1. 1Evidence, Innovation and Policy Department, UNAIDS, Geneva, Switzerland
  2. 2HIV Department, World Health Organization, Geneva, Switzerland
  3. 3Health Protection Agency, London, UK
  1. Correspondence to Dr Mary Mahy, Evidence, Innovation and Policy Department, UNAIDS, Avenue Appia 20, Geneva 1211, Switzerland; mahym{at}
  1. UNAIDS Report 2012 Guest Editors

  2. Karen Stanecki

  3. Peter D Ghys

  4. Geoff P Garnett

  5. Catherine Mercer

  • Received 5 August 2012
  • Accepted 15 October 2012


Background Countries measure trends in HIV incidence to assess the impact of HIV prevention and treatment programmes. Most countries have approximated trends in HIV incidence through modelled estimates or through trends in HIV prevalence among young people (aged 15–24 years) assuming they have recently become sexually active and have thus only been recently exposed to HIV.

Methods Trends in HIV incidence are described and results are compared using three proxy measures of incidence: HIV prevalence among young women attending antenatal clinics (ANCs) in 22 countries; HIV prevalence among young male and female nationally representative household survey respondents in 14 countries; and modelled estimates of adult (ages 15–49 years) HIV incidence in 26 countries. The significance of changes in prevalence among ANC attendees and young survey respondents is tested.

Results Among 26 countries, 25 had evidence of some decline in HIV incidence and 15 showed statistically significant declines in either ANC data or survey data. Only in Mozambique did the direction of the trend in young ANC attendees differ from modelled adult incidence, and in Mali and Zambia trends among young men differed from trends in adult incidence. The magnitude of change differed by method.

Conclusions Trends in HIV prevalence among young people show encouraging declines. Changes in fertility patterns, HIV-infected children surviving to adulthood, and participation bias could affect future proxy measures of incidence trends.


  • Contributions MM drafted the manuscript and conducted the analysis. KAM and JMGC contributed to the study design and revisions of the manuscript.

  • Funding None.

  • Competing interests None.

  • Provenance and peer review Commissioned; externally peer reviewed.

  • Open Access This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 3.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: and