Positive modification of injecting behavior among intravenous heroin users from Milan and northern Italy 1987-1989. NISDA Study.

The prevalence of risk behaviors in 933 intravenous drug users from Milan and other areas of Northern Italy was studied from 1 January 1987 to 15 April 1989. A preventive intervention, based on counseling with HIV antibody testing, was undertaken with i.v. drug users attending detoxication centers, and subjects were followed up in order to evaluate its effects. At enrollment all subjects reported heroin use, 18% also used cocaine and 6% morphine. Seventy-two per cent reported sharing or having shared syringes, with variation across geographical areas. Four hundred and sixty subjects were visited at least twice (mean follow-up was 10.4 months): 30% of these stopped injecting altogether and the frequency of injecting as well as of syringe sharing decreased whereas no improvement was seen in sexual behaviour. Detoxication therapy, combined with HIV testing and counseling proved effective in reducing heroin assumption and the frequency of syringe sharing, whereas the prevalence of risk behaviors in i.v. drug users at recruitment over the years 1987-1988 showed no change, or even increased, despite of general information and health education campaigns against AIDS.