Screening injecting drug users for sexually transmitted infections and blood borne viruses using street outreach and self collected sampling

Background: Injecting drug users (IDUs) are a marginalised population, who infrequently access health services for screening for sexually transmitted infections (STIs) and blood borne viruses (BBVs), and are at high risk of these infections. Objectives: To use street outreach and self collection of samples for STI screening, to establish the prevalence of BBVs and STIs, and to identify risk behaviours among a group of culturally diverse street based IDUs. Methods: This was a cross sectional study of 314 IDUs in the central business district of Melbourne, Australia, conducted over 3 years ( 1999 - 2002). We used street outreach as the recruitment strategy with staff "on foot'' in injecting and dealing locations, as well as self collected genital sampling to increase acceptance of screening for Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis by polymerase chain reaction (PCR). Individuals were screened for hepatitis A, B, and C, syphilis and HIV, and given the option of a self collected or clinician collected blood sample to increase acceptance of screening for BBVs. Results: Street outreach was highly effective and self directed STI sampling was more acceptable than practitioner directed sampling (76% versus 9% acceptance, p< 0.001). There was a high prevalence of hepatitis C (74%, 95% CI 69 to 79), STIs (8% ( 5 to 13)), and chlamydia (6% ( 3 to 10)), and past exposure to hepatitis A and B was common. High rates of recent sharing of injecting equipment, unprotected sex and casual sexual partners, together with low levels of awareness of current hepatitis C infection were identified. Conclusion: Street outreach and self collected genital samples facilitate screening for STIs and BBVs in IDUs and revealed a high prevalence of infections and risk behaviours.