and sexual—of the new social network and the seroprevalence background level of infection of new groups? Similar concerns were raised when methadone maintenance treatment programs were first introduced. Understanding these interactions across social networks is crucial to developing a better perspective on the changing patterns of risks and the progression of the HIV epidemic.

In addition to the issues listed above regarding needle exchange programs that are also relevant to evaluation studies of bleach distribution programs, there are others specific to bleach distribution programs.

Although limited in some ways (see Chapter 6), laboratory studies have shown that bleach is an effective disinfection agent for HIV-contaminated materials. Yet current epidemiologic studies have revealed that bleach disinfection, as currently practiced by injection drug users, does not appear to have a protective effect. It is therefore crucial that educational methods be developed to improve the level of compliance by injection drug users with the recommended disinfection protocol.

Laboratory studies are needed that carefully characterize the efficacy of bleach disinfection of needles and syringes under conditions that mimic field or actual use situations, accounting for bioburden and minimum effective contact times. These efforts should identify the optimal procedure while incorporating bioburden/consistency of use/contact time characteristics. Although some data are available, the panel noted limitations in current methods to assess efficacy (see Chapter 6).

In terms of recommended field procedures, studies are needed to determine if injection drug users can perform, and under what circumstances are willing/or not to perform, the multistep procedures that are recommended (e.g., ethnographic research). If current procedures are too complex or unacceptable to injection drug users, then research is needed to identify safe and effective procedures that can be performed by them. Moreover, effective educational strategies are urgently needed. Information on the diffusion of education intervention effects over time and the possible benefit of booster sessions to ensure sustained beneficial effects needs to be further studied. In addition, effective modes of disseminating bleach information to injection drug users need to be further explored (e.g., relative effectiveness of media, outreach).

The HIV and AIDS epidemiologic data clearly document the critical role of injection drug use in the current and future course of the HIV epidemic