"An experiment in Thailand involving 16,000 men and women has demonstrated for the first time a small but measurable protective effect of an AIDS vaccine. The vaccine, a complicated mixture of six 'prime' and 'booster' shots, reduced a person's risk of becoming infected by about one-third compared to people getting placebo injections. The results were barely significant on statistical grounds, perplexing for scientific reasons and unanticipated by most researchers. Nevertheless, the first positive results for an AIDS vaccine after two decades of experimentation was being called a milestone."
AIDS Vaccine Yields Limited Protective Effect for First Time!