Association of Syringe Source and Syringe Sharing in New York City

Background. HIV incidence is decreasing among injection drug users (IDU) in New York City, where sterile syringes are available from multiple legal sources. Nevertheless, many IDU continue to share syringes. We explored the relationship between syringe source and sharing.

Methods. We conducted a cross-sectional survey of active IDU recruited through respondent-driven sampling as part of CDC's National HIV Behavioral Surveillance. In a structured interview, participants were asked where they obtained syringes and whether they shared syringes in the past year.

Results. 500 eligible IDU completed the study between July – December 2005. Participants obtained syringes from a syringe exchange (71%), pharmacy (51%), medical provider (11%), friend (55%), or drug dealer (29%). 21% shared syringes. In multiple logistic regression controlling for demographic and injection-related factors (e.g., frequency of injection and number of drugs injected) associated with syringe source, IDU who obtained syringes from a syringe exchange were less likely to share syringes (OR=0.6, p<0.05) while IDU who obtained syringes from a friend (OR=2.2, p<0.01), or a dealer (OR=2.0, p=0.01) were twice as likely to share syringes. Obtaining syringes from a medical provider or pharmacy did not significantly influence sharing.

Conclusions. Syringe sharing varied by source of syringes. Obtaining syringes from drug dealers and friends increased the likelihood of sharing. Two sterile syringe sources (pharmacies and medical providers) were not associated with decreased syringe sharing. Only syringe exchange was associated with a significant decrease in syringe sharing. Exchange programs successfully reduce risk through counseling and support services that other sources cannot provide.