The growth of better-funded projects has triggered an identity crisis at UNAIDS.UNAIDS

Two new books are forcing the United Nations' AIDS programme to defend itself against claims that politics have distorted its mission.

In one, Berkeley epidemiologist James Chin argues that the Joint United Nations Programme on HIV/AIDS (UNAIDS) has overestimated the potential size of the AIDS pandemic. That way, Chin says, the agency can claim credit when actual infection rates are lower than the projections.

In the second, writer Helen Epstein says that UNAIDS has dodged the issue of sexual behaviour in Africa. Although reducing number of sexual partners can slow the spread of HIV, Epstein says UNAIDS has shied away from this message for political and cultural reasons.

Some praise the books for providing much-needed scrutiny of UNAIDS. In a book review published today in Nature, Stephen Lewis, former UN special envoy for AIDS in Africa, calls them "liberating" (see 'Time for a change?').

And the University of Ottawa's Amir Attaran says the United Nations has a general problem with book-keeping. The United Nations has set a series of targets called the Millennium Development Goals, which call for improvements such as reducing HIV infection, child mortality and poverty by 2015.

But Attaran alleges the United Nations has failed to properly measure progress towards these goals, rendering them all but meaningless. "It's got to be the greatest swindle in all of development," Attaran says.

Defending party

Other observers defend UNAIDS against the claim of distorting data. The crux of Chin's argument is that UNAIDS epidemiologists have erred by surveying pregnant women for HIV infection at prenatal clinics, then extrapolating to the general population.

More recent surveys of HIV in the general population have prompted UNAIDS to lower its estimates in some African and Asian countries.

But those who participate in the process say this was never about politics, but more about adapting calculations to the available data. And, they add, UNAIDS has always said that data from different methods aren't directly comparable.

"It has always been a data-based, not a political process," says Tim Brown, an epidemiologist at the East-West Center in Honolulu who collaborates with UNAIDS. "The epidemiology team at UNAIDS has gone out of its way to stress that data can only be interpreted in terms of trends based on the same methodology," he says.

UNAIDS also says that it has long emphasized the value of reducing the number of sexual partners, including in a 2005 document, "Intensifying HIV Prevention".

Some observers support the claim. "As far as I am aware, reducing partner numbers has been a prevention message for the past 20 years," says Geoff Garnett at Imperial College London, which coordinates the UNAIDS Epidemiology Reference Group.

Identity crisis

The broader picture behind the criticisms is that UNAIDS is searching for relevance. The agency was formed a decade ago to focus attention on the disease when there was little international funding or political commitment to fight it.

Now, huge entities such as the Global Fund to Fight AIDS, Tuberculosis and Malaria and the US President's Emergency Plan for AIDS Relief (PEPFAR) are pouring unprecedented resources into the problem. Leadership has largely shifted to these bodies and away from UNAIDS, which is hampered by bureaucratic constraints and a smaller budget.

That makes UNAIDS a relatively soft target, some say. "UNAIDS is easy to shoot at, because they don't have a lot of money compared with donors such as PEPFAR and the Global Fund," says Chris Beyrer, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland. "What are they supposed to do? They're not an enormously powerful entity."

But that begs the question of what to expect from UNAIDS in the future. With little money and clout, the agency must find a way to deal with its identity crisis.

Additional reporting by Emma Marris

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