More than twenty years after the discovery of HIV there is still no preventive vaccine against AIDS. This is a major reason why the world is still facing an expanding pandemic of HIV and AIDS. However, the idea of a preventive vaccine as a 'magic bullet' to provide a simple solution to the problem of HIV and AIDS is not realistic.

The more likely prospect, still years away, is of a range of partially effective vaccines which must be combined with other approaches to HIV prevention and access to treatment for people living with the virus. Testing and providing such a vaccine raises many challenging issues but may also offer opportunities to strengthen the broader response to the epidemic.

While the first vaccine to complete a full-scale clinical trial has so far failed to show any convincing evidence of protection, other more credible candidate vaccines are entering trials in increasing numbers. Progress has been made by showing that vaccines can alter the course of HIV-like disease in monkeys and the identification of antibodies that can protect against infection with a wide range of HIV strains.

HIV has focussed attention on the need for new vaccine technologies (discussed in the HIV & AIDS Treatments Directory) and these in turn raise questions about how an HIV vaccine can be evaluated and, if effective, made available to those who need it.

Preventive vaccines against HIV and AIDS are actively being pursued by governments and inter-governmental agencies, the pharmaceutical industry and non-governmental organisations. Progress towards this important but challenging goal requires a long-term commitment to partnerships across sectors, with the active involvement of communities affected by HIV.