A shot at immunity: volunteers line up to try live-virus HIV vaccine.

When the International Association of Physicians in AIDS Care started its vaccine initiative in August, the Chicago-based group hoped to garner some attention for an HIV vaccine. And when the group announced last month that it had lined up 50 volunteers willing to be injected with a live-virus vaccine, they found it.

The idea of human guinea pigs willing to risk infection for the sake of science brought attention to the lack of progress on an HIV vaccine--just what IAPAC wanted. "We wanted to see vaccine development have the same intense focus on it as research for new treatment," says Jose Zuniga, deputy director of IAPAC and a vaccine volunteer. "It just hasn't happened, and it may now. "

Supporters of the trial, which would establish the safety of the vaccine, have to convince the government of the merit of their cause. In addition to needing legislation that would indemnify the vaccine maker from litigation should something go wrong, the vaccine's proponents also need approval from the Food and Drug Administration before they can begin testing. The soonest the trial could begin would be a year from that approval.

The trial would be only the first of three required to determine the efficacy of the vaccine, which means that even a successful vaccine would be years away from the market. Other vaccine trials, which do not use live forms of HIV and thus pose no risk of HIV infection, already are under way. So far none of them has shown breakthrough potential.

Zuniga says that a live-virus vaccine would have the benefit of lifetime immunity without the need for booster shots. As for the fear of infection, he says, "At what point does it become irrational when there is the potential to prevent 8,000 new infections a day?" Apparently others agree. Since the news of the vaccine broke, IAPAC has been besieged with hundreds of telephone calls from would-be volunteers.

Volunteers likely will be in demand in the months ahead. The federal National Institute of Allergy and Infectious Diseases has awarded nearly $12 million in grants to study HIV vaccines.