Epidemiology

UNAIDS and WHO modify their estimates as new data, research and analyses emerge. As advances are made to the methodology of data collection and surveillance, the estimates of numbers of people living with HIV are revised to reflect these improvements. Revisions are also made retrospectively for each year to allow for a more accurate assessment of the epidemic's evolution over time. For this reason, it is inaccurate to draw conclusions by comparing the estimates from one report to another.

Report on the global AIDS epidemic

This report draws upon and publishes the best available data from countries and provides an overview and commentary on the epidemic and the international response. Access 2010 materials

Archive: 2008 | 2006 (pdf) | 2002 (pdf) | 2000 (pdf) | 1998 (pdf)

Women in white shirt and yellow cap smiling

Epidemiological data

Data slides from the latest Global Report and AIDS epidemic update publications

Latest data:

HIV estimates with uncertainty bounds 2009 (2010, 78Kb, xls)
HIV estimates with uncertainty bounds 2001, 2009 (2010, 163Kb, xls)
HIV estimates with uncertainty bounds 1990-2009 (2010, 1.3Mb, xls)
Country fact sheets

AIDS Epidemic Update

Global and regional estimates:

Archive: 2009 | 2007 (pdf) | 2006 (pdf) | 2005 (pdf) | 2004 (pdf) | 2003 (pdf) | 2002 (pdf) | 2001 (pdf) | 2000 (pdf) | 1998 (pdf)

Epidemiology publications

Man and woman leaning against shack in sun

Estimation methods

UNAIDS/WHO Working Group on Global HIV/AIDS and STI Surveillance

Global surveillance of HIV/AIDS and STI is a joint effort of UNAIDS and WHO. The UNAIDS/WHO Working Group on Global HIV/AIDS and STI Surveillance is the main coordination and implementation mechanism to compile the best information available and to improve the quality of data needed for informed decision-making and planning at national, regional and global levels.

The Working Group gathers examples of best practices and experiences from all regions on the collection of HIV, AIDS, STI and behavioral data at country level and uses them to develop global guidelines and training materials to be used in designing, monitoring and evaluating national surveillance systems.

Epi Alert

UNAIDS quarterly update on HIV epidemiology:

2010 Q2: Network scale-up: A promising method for national estimates of the sizes of populations at higher risk
2010 Q1: Methods for estimating HIV incidence
Guidance for inclusion of HIV prevalence measurement in national surveys (UNAIDS/WHO Working Group On Global HIV/AIDS and STI Surveillance, 2010)

Press centre

17 May 2012: International Day Against Homophobia and Transphobia. More

10 May 2012: UNAIDS calls on Greece to protect sex workers and their clients through comprehensive and voluntary HIV programmes. More

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