Int Conf AIDS. 1996 Jul 7-12;11(2):34 (abstract no. We.C.214). Unique
Issues In 1988, prevalence of HIV-1 infection among Bangkok IDUs in
treatment increased from 1% to 40%. Despite available interventions, HIV
transmission continues at an alarming rate. In response to this
epidemic, efforts are underway to establish cohorts of persons at high
risk for HIV infection for possible HIV-1 vaccine efficacy trials.
Project Development of baseline information and an infrastructure that
could be used to conduct a phase III HIV-1 vaccine efficacy trial.
Results Despite drug treatment and other education and intervention
programs for IDUs in Bangkok, retrospective and cross sectional studies
in 1991-93 estimated an HIV-1 incidence rate of about 10% per year.
Incident HIV-1 infection was associated with needle sharing,
incarceration, and being single. While the initial epidemic among IDUs
was primarily due to HIV-1 subtype B, by 1994, 20% of infections were
due to subtype E, which is responsible for the larger heterosexual
epidemic in Thailand. Of an estimated 40,000 active IDUs in Bangkok, the
BMA annually enrolls about 8,000 individual IDUs into a network of 15
drug treatment clinics, primarily offering methadone detoxification. In
1995, a phase I/II rgp 120 MN HIV-1 vaccine trial was conducted among 33
recovering IDUs in Bangkok. Also in 1995, among 1600 IDUs screened,
willingness to participate in a prospective cohort study was high (83%);
500 HIV-negative IDUs were enrolled into such a study; and successful
follow up at 4 months was 90%. Conclusions More than 4,000 HIV-negative
IDUs at high risk for HIV-1 infection are accessible through drug
treatment clinics of the BMA. An ongoing prospective cohort study will
assess rates of successful follow up and HIV-1 incidence and will allow
for the characterization of infecting HIV strains. This setting may
allow for efficacy evaluation of HIV vaccines against the B and E
subtypes of HIV-1.
*HIV-1/DRUG EFFECTS *Substance Abuse, Intravenous