HIV/AIDS preventive vaccine ‘prime-boost’ phase III trial: foundations and initial lessons learned from Thailand

Abstract

The first case of AIDS in Thailand was reported in September 1984. The number of newly reported AIDS cases increased every year peaking in 1998 with 27 528 cases. As of 31 December 2001 the year of the decision to conduct a phase III vaccine trial the cumulative number of reported AIDS cases was 196 373. Among those reported cases unsafe sex accounted for 85.6% the highest proportion by mode of transmission followed by intravenous drug use (3.9%) and mother-to-child transmission (3.3%). As of the end of 2004 the estimated number of HIV/AIDS cases is summarized in Table 1. The HIV epidemic is now spreading into every subpopulation depending on risk behaviors and shifting from specific risk groups to the general population. (excerpt)