During the late 1990s and early 2000s response to HIV/Aids was revitalised at both the global and the African levels. Leadership passed from the WHO to the Joint United Nations Programme on Aids (UNAIDS) in 1996, but the main dynamic came from the discovery of antiretroviral drugs (ARVs) that could suppress, but not cure, the disease. ARVs brought hope, the crucial quality needed to activate health workers and people with HIV/Aids. As with previous African diseases, it needed such a magic bullet - penicillin for syphilis, dapsone for leprosy - to stimulate a mass treatment campaign. Yet to make ARVs available to millions of infected Africans required radical changes of attitude among international donors, shifts of power in the pharmaceutical industry, and infusions of energy into African regimes - infusions that might in turn require pressure by those in desperate need of drugs. Here the source of HIV's power - its slow action and long incubation - became its weakness, for unlike many other epidemic diseases it gave infected people time to organise a counter-attack. By 2005 only a small minority of Africans needing ARVs were receiving them and it was increasingly obvious that the drugs, while immensely valuable to individuals, could not reverse the epidemic. The search for a vaccine, which in principle could achieve that goal, was still desperately slow. Nevertheless, between 1996 and 2005 the scene was transformed. Hitherto the virus had held the initiative. Now the victims were taking it.

UNAIDS took responsibility for coordinating international action against the epidemic in January 1996. It grew out of the impatience with WHO displayed by richer, more interventionist international agencies from the early 1990s as they developed separate and often competing Aids programmes. Only the United Nations, it was realised, could bring these agencies together, and even then there was doubt until 1994 whether the World Bank would join the coalition. Based alongside the WHO at Geneva, UNAIDS did not take over its medical functions or those of other agencies, nor was it a funding body. Rather, it sought to coordinate, define, and publicise policies, acting through ‘theme groups’ in each country bringing together the local representatives of the various international agencies.