Faculty Bibliography

Focusing on the social environment as well as the individual should both enhance our understanding of HIV transmission and assist in the development of more effective prevention programs. Networks are an important aspect of drug injectors' social environment. We distinguish between (1) risk networks (the people among whom HIV risk behaviors occur) as vectors of disease transmission, and (2) social networks (the people among whom there are social interactions with a mutual orientation to one another) as generators and disseminators of social influence. These concepts are applied to analyses of data from interviews with drug injectors in two studies. In the first study drug injectors' risk networks converge with their social networks: 70% inject or share syringes with a spouse or sex partner, a running partner, or with friends or others whom they know. Qualitative data from interviews with injectors in the second study also show that the social relationships between drug injectors and members of their risk network are often based on long-standing and multiplex relationships, such as those based on kinship, friendship, marital and sexual ties, and economic activity. In the first study the vast majority of injectors, over 90%, have social ties with non-injectors. Injectors with more frequent social contacts with non-injectors engage in lower levels of injecting risk behavior. Risk settings may function as risk networks: injectors in this study who inject at shooting galleries are more likely than those who do not to rent used syringes, borrow used syringes and inject with strangers. Since the adoption of a network approach is relatively new, a number of issues require further attention. These include: how to utilize social networks among drug injectors to reduce risk through peer pressure; how to promote risk reduction by encouraging ties between injectors and non-injectors; and how to integrate biographical and historical change into understanding network processes. Appropriate methodologies to study drug injectors' networks should be developed, including techniques to reach hidden populations, computer software for managing and analyzing network data bases, and statistical methods for drawing inferences from data gathered through dependent sampling designs.

To determine risk factors for HIV-1 among drug injectors in Rio de Janeiro, where cocaine is the dominant drug of injection, subjects were recruited using the criteria and interview instrument of the World Health Organization's Cross-National Study of HIV infection and risk behaviour in injecting drug users. HIV antibody test results were derived both from serum tests and from self-reports of previous tests (documented evidence of self-reported seropositivity was required). The analytical sample consists of 123 subjects, recruited both at drug abuse treatment sites and at street locations. Of 27 subjects with both serological and self-reported antibody status data, 20 reported previous negative tests; of these three had positive sera and may have seroconverted. Seven subjects reporting prior positive serostatus all tested positive. For the 123 subjects, seroprevalence was 34%. Independent significant risk factors in multivariate logistic regression with backwards elimination are: years of injection greater than 5; being a male who has had sex with men in the previous 5 years; and not having taken deliberate steps to protect oneself against AIDS. These findings indicate that homosexual/bisexual male drug injectors may be a bridge group through which HIV is entering drug-injecting networks in Rio de Janeiro. Efforts by drug injectors to reduce their risk of infection seem to have protective effects. This underscores the importance of HIV prevention efforts aimed at drug injectors.

Human immunodeficiency virus (HIV) seroconversion was studied in a group of 173 injection drug users in Bangkok, Thailand, who had been previously tested for HIV and were interviewed and retested in the fall of 1989. Ten percent of the group had seroconverted. Two factors protected against HIV seroconversion: having stopped sharing injection equipment in response to the acquired immunodeficiency syndrome (AIDS) and having a regular sexual partner. The association between self-reported deliberate risk reduction and reduced HIV seroconversion among persons continuing to inject illicit drugs indicates that injection drug users can change their behavior in response to AIDS and will accurately report on the behavior change, and that the changes can protect against HIV infection.

OBJECTIVES/OBJECTIVE:To study how condom use in injecting drug users' (IDU) relationships differs according to whether they are HIV-infected, and to whether their sex partner is an IDU. DESIGN AND METHODS/METHODS:A total of 317 street-recruited IDU were HIV-antibody tested and interviewed about 421 relationships with particular sex partners. RESULTS:Condoms were consistently (100%) used in sex between partners (during the previous 30 days) in 33% of these relationships, and their use was significantly more frequent in relationships of seropositive IDU and in relationships with non-IDU partners. In relationships between seropositive IDU and non-IDU, consistent condom use was reported to be high (68%); this remained unchanged under multivariate controls. CONCLUSIONS:Self-reported condom use by IDU in New York, with its relatively mature epidemic, appears to be concentrated where it may most reduce the spread of HIV to non-IDU heterosexuals, i.e., in relationships between infected IDU and non-IDU partners. Differential condom use by serostatus and by partners' drug injection should be incorporated into mathematical models of the HIV epidemic. Causes of the high level of condom use in this subset of relationships may include drug injector altruism and pressure by sex partners; prevention programs should develop ways to use both of these factors to motivate increased condom use.