HIV Vaccines - Accelerating the Development of Preventive HIV Vaccines for the World: Summary Report and Recommendations of an International Meeting

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* Humanitarian and social: Much of the burden of HIV is placed upon those least able to
cope with it: the poor, the marginalized, and the young. Africa, the region with the
weakest economy in the world, has over 60% of the current HIV burden. In many areas
individuals who are not in a position to adopt risk-reduction measures, such as young
women, are placed at a high risk of infection, not because of their own activities, but
rather by the activities of their partner. Premature mortality and AIDS-related morbidity
among adults are also having a serious impact on child welfare. For instance, the WHO
estimates that in the 1990s there will be over 10 million AIDS orphans in Africa.
* Economic: AIDS primarily affects young adults in the most productive age groups and as
a result the indirect costs associated with the epidemic are significant. The reduction in
the supply and productivity of labor from HIV-related mortality and morbidity, and the
financial burden of paying for HIV-related treatment and other needs have serious
economic consequences for households, productive enterprises, and countries. In the
case of affected households the illness or death of a productive member can tip
vulnerable households into poverty. The direct costs of the epidemic are also substantial.
By 1993, HIV-related medical care costs in the developed countries had already reached
US$ 4.8 billion a year and US$ 340 million in developing countries - figures that will
continue to rise in the foreseeable future.
The participants at the Bellagio meeting also expressed concern about the long-term financial
sustainability of the current range of prevention activities. Behaviour modification activities are
both costly and labor intensive and will almost certainly need to be continued indefinitely to
ensure that newly sexually active individuals are educated and to reinforce the knowledge of
those already sexually active. The limited impact that prevention activities appear to be having on
the rate of spread of HIV, and the decreasing prominence of HIV and AIDS as a health and
development issue in developed countries, however, may lead donors to reassess their financial
commitment to prevention, with serious consequences for prevention activities in the future.
1.2 Ideal technical characteristics of a preventive HIV vaccine
A preventive HIV vaccine intended for use throughout the world ideally would have the following
technical characteristics:
* Protection: Able to stimulate the production of durable, functional protective immune
responses against most, it not all, sub-types of HIV2 to which an individual is likely to be
exposed, and from all potential routes of exposure. The mobility of people (and therefore
viruses) highlights the need to protect individuals not just from the sub-types currently
circulating where they live but also from those they may encounter in the future.
2 Isolates of HIV from different geographic regions, from different individuals in the same
region, and even from a single infected individual often carry distinctly different genetic
sequences. Isolates can be grouped by genetic relatedness; nine groups or sub-types of HIV-1
have been identified so far. In North America one sub-type (B) is prevalent in the infected
population. In a number of regions, however, several different sub-types can be found.