With clinical trials now underway, it is natural to expect that a safe and effective vaccine against HIV will soon spell the end of AIDS in this country. But consider a more likely scenario:

Immediately after the Food and Drug Administration licenses the vaccine, the Centers for Disease Control and Prevention (CDC) recommend the immunization of all high-risk gay men, prostitutes, and intravenous drug users. Congress and state legislatures, however, do not rush to approve the funds needed to reach these groups. Years pass, and HIV infection rates barely budge.