The Vancouver Injection Drug Users Study (VIDUS) is UHRI's longest-running cohort study. VIDUS participants, who number about 1500, have been followed since 1996 and were originally recruited through street outreach efforts. Every six months, VIDUS participants provide blood samples to be tested for HIV and hepatitis C, and they're interviewed about their drug use patterns and practices, health status and access to health and social services, and interactions with the criminal justice system. Data from this cohort have been the basis for hundreds of published scientific studies.
The analysis of this information has contributed to a number of policy developments, including the expansion of needle exchange and distribution services, and the evaluation of Insite, Vancouver's supervised injection site. In addition to the valuable information gained through VIDUS, the study also performs an important public health function by providing regular HIV and hepatitis C testing (including pre- and post-test counselling) to local injection drug users.
Recently, the original VIDUS cohort was divided into two separate studies: VIDUS now follows HIV-negative participants and its sister study ACCESS follows HIV-positive injection drug users.