Little change in sexual behavior in injecting drug users in Amsterdam.

To assess heterosexual behavior of injecting drug users (IDUs) over time, we studied 174 IDUs with regard to their steady, casual, and commercial partners over a 1-year period. Within this year a large national AIDS prevention campaign had been implemented in the Netherlands. In addition, condom use was discussed with participants during various follow-up visits. We found a large turnover in IDUs who reported having steady, casual, or commercial partners. Limited change in sexual behavior occurred: the frequent use of condoms increased only with casual partners (from 30 to 49%), and the proportion of female IDUs working as prostitutes decreased (from 56 to 41%). At both measurements IDUs who knew that they were HIV infected used condoms more frequently with their steady partners and tended to report fewer casual partners than those who knew they were not infected. In addition, HIV-infected women tended to be less active in prostitution than noninfected women. We conclude that large-scale voluntary testing of IDUs, together with repeatedly discussing the risks of sexual transmission of HIV and the use of condoms as a preventive measure (counseling) may, at least among HIV-infected IDUs, result in some risk reduction. Health education to increase the use of condoms should also be directed at IDUs who at present do not have steady, casual, or commercial partners.