Sex Transm Infect 88:i76-i85 doi:10.1136/sextrans-2012-050719
  • Supplement

Focusing the HIV response through estimating the major modes of HIV transmission: a multi-country analysis

Open Access
  1. on behalf of the International Collaboration on Estimating HIV Incidence by Modes of Transmission
  1. 1Evidence, Policy and Innovation Department, UNAIDS, Geneva, Switzerland
  2. 2HIV Operations Unit, UNITAID, Geneva, Switzerland
  1. Correspondence to Dr Eleanor Gouws, Evidence, Policy and Innovation Department, UNAIDS, 20 Avenue Appia, Geneva 1211, Switzerland; gouwse{at}
  1. UNAIDS Report 2012 Guest Editors

  2. Karen Stanecki

  3. Peter D Ghys

  4. Geoff P Garnett

  5. Catherine Mercer

  • Accepted 24 September 2012


Objective An increasing number of countries have been estimating the distribution of new adult HIV infections by modes of transmission (MOT) to help prioritise prevention efforts. We compare results from studies conducted between 2008 and 2012 and discuss their use for planning and responding to the HIV epidemic.

Methods The UNAIDS recommended MOT model helps countries to estimate the proportion of new HIV infections that occur through key transmission modes including sex work, injecting drug use (IDU), men having sex with men (MSM), multiple sexual partnerships, stable relationships and medical interventions. The model typically forms part of a country-led process that includes a comprehensive review of epidemiological data. Recent revisions to the model are described.

Results Modelling results from 25 countries show large variation between and within regions. In sub-Saharan Africa, new infections occur largely in the general heterosexual population because of multiple partnerships or in stable discordant relationships, while sex work contributes significantly to new infections in West Africa. IDU and sex work are the main contributors to new infections in the Middle East and North Africa, with MSM the main contributor in Latin America. Patterns vary substantially between countries in Eastern Europe and Asia in terms of the relative contribution of sex work, MSM, IDU and spousal transmission.

Conclusions The MOT modelling results, comprehensive review and critical assessment of data in a country can contribute to a more strategically focused HIV response. To strengthen this type of research, improved epidemiological and behavioural data by risk population are needed.


  • Collaborators

  • International Collaboration on Estimating HIV Incidence by Modes of Transmission

  • UNAIDS Geneva (MOT): Eleanor Gouws, Paloma Cuchi, Peter Ghys

  • UNAIDS Geneva (NASA): Benjamin Gobet

  • Asia UNAIDS Regional Office: Amala Reddy. International consultants: Tim Brown, Virginia Loo, Wiwat Peerapatanapokin, Tobi Saidel, Nalyn Siripong

    National study teams: Myanmar: Aye Aye Sein, San Hone, Khin Zarli Aye, Markus Bühler; Philippines: Genesis Samonte, Noel Palaypayon, Zimmbodilion Y Mosende

  • Indonesia: Asep Kurniawan, Victoria Indrawati, Wenita Indrasari, Asep Eka Nur Hidayat, and Lely Wahyuniar; Nepal: Deepak Karki, Amdo Kumar Poudyal, Alankar Malviya.

  • Eastern Europe and Central Asia UNAIDS Regional Office: Lev Zohrabyan. International consultants: Kelsey Case

    National study teams: Moldova: Otilia Scutelniciuc, Valeriu Plesca, Stela Bivol, Alexandrina Iovita; Armenia: Samvel Grigoryan, Arshak Papoyan.

  • Latin America and Caribbean UNAIDS Regional Office: Marjolein Jacobs. International consultants: Annick Borquez, Juan F Vesga National study teams: Dominican Republic: Yordana Doloros, Tessie Caballero Vaillant, Elizabeth Conklin-Ballester; El Salvador: Ana Isabel Nieto, José Salvador Sorto, Herbert Betan court, Marta Aurelia Martinez; Peru: Jorge Alarcon, Monica Pun, Luis Suarez, Romina Tejada, Cesar Gutierrez; Guyana: Otilia St Charles, Rosalinda Hernandez; Nicaragua: Enrique Beteta Acevedo, Luis Carballo Palma, José Medrano, Dina Soza, Ofelia Chicas.

  • Middle East and North Africa UNAIDS Regional Office: Hamidreza Setayesh. International consultants: Laith Abu-Raddad

    National study teams: Morocco: Ghina R Mumtaz, Ahmed Zidouh, Houssine El-Rhilani, Aziza Bennani, Kamal Alami; Iran: Maryam Nasirian, Aliakbar Haghdoost, Fardad Doroudi.

  • Southern and East Africa UNAIDS Regional Office: Susan Kasedde (now UNICEF). International consultants: Mark Colvin, John Stover. The World Bank: Nicole Fraser.

    National study teams: Kenya: Lawrence Gelmon, Patrick Kenya, Francis Oguya, Boaz Cheluget, Girmay Haile; Lesotho: Motlalepula Khobotlo, Relebohile Tshehlo, John Nkonyama, Mikaela Hildrebrand; Mozambique: Mauricio Cysne, Mari Luntamo; South Africa: Reshma Kassanjee, Alex Welte, Henry Damisoni; Swaziland: Sibusiso Mngani, Happiness Mkhatshwa, Tyrone Lapidos, Thandi Khumalo, Sanelisiwe Tsela, Nhlanhla Nhlabatsi, Helen Odido; Uganda: Fred Wabwire-Mangen, Martin Odiit, Wilfred Kirungi, David Kaweesa Kisitu, James Okara Wanyama; Zambia: Harold Witola, Celestine Buyu, Michael Gboun; Zimbabwe: Nomasomi Mpofu, Victoria James, Amos Milanzi, Masauso Nzima.

  • West Africa UNAIDS Regional Office: Alliou Assani. International consultants: John Stover, Annick Borquez, Catherine Lowndes, Michel Alary. World Bank: Juliana Victor-Ahuchogu

    National teams: Benin: Alphonse Guedeme, Gatien Ekanmian, Justin Toussou; Burkina Faso: Frederic Kintin, André Kaboré, Jean-Baptiste Gatali; Côte d'Ivoire: Karim Seck, Eugene Eba, Pascal Eby; Ghana: William Bosu, Kenneth Zeboah, Rangaiyan Gurumurthy; Nigeria: Joseph Nnorom, Fajemisin Oluwole, Job Sagbohan; Senegal: Karim Seck.

  • Contributors Both authors contributed to the overall design and management of the modes of transmission process in various regions across the world. EG wrote the first draft of the paper. Both authors contributed to the analysis, interpretation and writing of the final manuscript. Country and regional collaborators coordinated the country specific studies, analyses and reports, and provided comments on the final paper.

  • Competing interests None.

  • Provenance and peer review Commissioned; externally peer reviewed.

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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