Addiction (1999) 94(5), 675±683 RESEARCH ARTICLE Risk factors among IDUs who give injections to or receive injections from other drug users ALEX H. KRAL, RICKY N. BLUTHENTHAL, ELIZABETH A. ERRINGER, JENNIFER LORVICK & BRIAN R. EDLIN Urban Health Study, Institute for Health Policy Studies, School of Medicine, University of California, San Francisco, USA Abstract Aims. To assess risk factors associated with injection drug users (IDUs) who give injections to or receive injections from other IDUs. Design and setting. IDUs were recruited into a cross-sectional study using targeted sampling methods in Oakland, Richmond, and San Francisco, California from August 1996 to January 1997. ªStreet docsº are IDUs who reported having given injections to other IDUs in the past month. ªInjection recipientsº are IDUs who reported having received injections from other people in the past month. Participants. Of 1166 IDUs interviewed, 283 (24%) reported being injection recipients and 427 (37%) reported being street docs. Measurements. Socio-demographic characteristics and injection-related risk behaviors. Findings. Injection recipients and street docs were signi®cantly more likely (p , 0.001) than other IDUs to report sharing syringes (33% of injection recipients, 21% of street docs and 7% of others), cookers (71% of injection recipients, 55% of street docs and 24% of others), rinse water (44% of injection recipients, 35% of street docs and 13% of others), and ®lters (60% of injection recipients, 47% of street docs and 20% of others). In a logistic regression model, injection recipients (adjusted odds ratio (AOR) 5 4.29) and street docs (AOR 5 1.91) were more likely than other IDUs to report having shared syringes. Conclusions. Giving and receiving injections is common among IDUs in the San Francisco Bay area. Qualitative and epidemiological studies are needed to understand better the infectious disease risks associated with giving and receiving injections. Interventions need to address these issues and provide practical solutions. Introduction Illicit drug injection is associated with several infectious diseases. It is now estimated that injec- tion drug use accounts for as many new HIV infections (estimated at between 40 000 and 80 000 per year) in US urban settings as unpro- tected male-to-male sex (Holmberg, 1996). More than a third (36%) of the 573 000 adult acquired immune de®ciency syndrome (AIDS) cases in the United States are associated either directly or indirectly with injection drug use (CDC, 1996). Infection with viral hepatitis, speci®cally hepatitis B virus (HBV) and hepatitis C virus (HCV), is highly prevalent and a signi®cant source of morbidity and mortality among IDUs (Alter, 1993). In 1988, injection drug use accounted for 43% of HBV cases with known risk factors (Alter et al., 1990). Epidemio- logical studies have found HBV seroprevalence among IDUs ranging from 51% to 90% in the Correspondence to: Alex H. Kral MS, Epidemiologist, Urban Health Study, 3180 18th Street Suite 302, San Francisco, CA 94110, USA. Tel: (415) 476 3400; fax: (415) 476 3406; e-mail: alkral@itsa.ucsf.edu Submitted 20th March 1998; initial review completed 17th August 1998; ®nal version accepted 23rd November 1998. 0965±2140/99/050675±09 $9.50 Ó Society for the Study of Addiction to Alcohol and Other Drugs Carfax Publishing, Taylor & Francis Ltd