HIV-1 incidence determined retrospectively among drug users in Bangkok, Thailand.

摘要: Objective To measure trends in the incidence of HIV-1 infection among drug users treatment at Thailand's largest detoxification unit. Design A retrospective cohort was established using computed, existing test results 26 396 inpatients and outpatients admitted for 47 907 courses from August 1987 to 1992. Methods Matching patient record numbers showed that 10 050 (38.1%) patients had been two or more times during period. From these, we selected a 7807 initially HIV-negative patients. Subsequent seroconversions them were assumed have occurred with uniform probability throughout interval between last first HIV-positive tests. Results There 2311 (29.6%) cohort. 5974 (76.5%) who injecting (IDU) escalated 20 new infections per 100 person-years (PY) observation peak 57 PY 1988, then gradually declining stable rate about 11 1991 Non-IDU (smokers, inhalers) constituted 683 (8.8%) patients, rates varying 0.2 five PY. 'Mixed' users, defined as individuals reporting different routes administration on admissions, composed 1150 (14.7%) an IDU non-IDU. Prevalence seropositivity all increased rapidly, 1% early 1988 40% by 1989, has remained through Conclusions Prevention efforts must continue IDU, since recent annual remains high >10 Such suggests this group should be considered vaccine efficacy trials. Stable prevalence can mask substantial population turnover.