Parenteral and Sexual Transmission of Human Immunodeficiency Virus in Intravenous Drug Users: A Study of Seroconversion

Abstract

To evaluate the role of parenteral and sexual transmission of human immunodeficiency virus, we studied seronegative intravenous drug users recruited from 25 drug dependence treatment centers in northern Italy. All attending intravenous drug users were asked for their consent and screened for antibodies to human immunodeficiency virus; those who were seronegative were enrolled, interviewed about their habits, and invited to follow-up visits. Between 1987 and 1989, 1,195 seronegative intravenous drug users were enrolled, 635 were followed up (mean duration, 11.9 months), and 35 seroconversions were observed. The incidence rate ratios were 3.3 (95% confidence interval (CI) 1.4-7.5) for subjects aged less than 20 years, 2.4 (95% CI 1.2-4.7) for less than 2 years of intravenous drug use, 2.2 (95% CI 0.9-5.5) for syringe sharing, and 1.0 for subjects with a sexual partner who had tested positive for human immunodeficiency virus. A case-control approach, using logistic regression and adjusting for sex, age, area, and prevalence, showed odds ratios of 13.2 (95% CI 3.1-56.8) for frequent syringe sharing and 4.0 (95% CI 1.5-10.4) for sexual contacts with seropositive partners; frequent use of condoms was associated with a reduction in risk that did not reach statistical significance. Parenteral transmission is the most important route of infection with the human immunodeficiency virus among intravenous drug users, and sexual transmission plays a relevant, additive role.

The influence of needle exchange programs on injection risk behaviors and infection with hepatitis C virus among young injection drug users in select cities in the United States, 1994–2004

“…Thus, even with the limitations noted above, our findings suggest that NEPs may help to prevent HCV transmission through changing behaviors that influence risk. Moreover, these findings extend those from several studies that have examined the impact of NEPs on HIV infection (Nicolosi et al, 1992;Hurley et al, 1997;Wodak and Cooney, 2005) providing additional support for the effectiveness of NEPs in reducing transmission from blood-borne infections. NEPs should thus be considered as one vital component, among other program strategies, that seek to prevent transmission of HCV infection among IDUs.…”

Multiple Access to Sterile Syringes for Injection Drug Users: Vending Machines, Needle Exchange Programs and Legal Pharmacy Sales in Marseille, France

“…After a trial of 1 year in Marseille, syringe vending machines appear to be a complementary tool to existing NEPs by reaching a different, and in particular a younger segment of IDUs who have been reported to have the highest risk of acquiring HIV, HBV and HCV infections [18][19]. The coexistence of both types of programs seems necessary to fulfill the additional needs of IDUs for sterile syringes that cannot be covered by legal pharmacy sales in a single city.…”

Change in AIDS risk behaviors among impoverished minority women after a community-based cognitive-behavioral outreach program

“…Approximately half of the women with AIDS are injecting drug users (IDUs) (Diaz et al, 1994); nearly three-quarters of seropositive women have contracted HIV from heterosexual contact with IDUs (Bowen & Trotter, 1995). Female IDUs have higher seroincidence rates of AIDS as compared with their male counterparts, most likely as a result of heterosexual transmission (Nicolosi, Correa-Leite, Musicco, Molinari, & Lazzarin, 1992) as well as through the sharing of contaminated injection equipment (Baker, Heather, Wodak, Dixon, & Holt, 1993;Khalsa, Kowalewski, Anglin, & Wang, 1992).…”