Low rates of hepatitis C testing among people who inject drugs in Thailand: implications for peer-based interventions

In this paper, we review evidence of HCV prevalence among injecting drug users (IDUs) worldwide. We undertook a desk-based review of both 'grey' and published literature released between 1998 and 2005. Data on HCV prevalence among IDUs was found in 57 countries and in 152 sub-national areas. We found reports of HCV prevalence of at least 50% among IDUs in 49 countries or territories. Available regional estimates varied widely, from 10 to 96% in Eastern Europe and Central Asia, from 10 to 100% in South and South-East Asia, from 34 to 93% in East-Asia and the Pacific, from 5 to 60% in North Africa and the Middle-East, from 2 to 100% in Latin America, from 8 to 90% in North America, from 25 to 88% in Australia and New Zealand, and from 2 to 93% in Western Europe. Only in Colombia and Lebanon were all HCV prevalence estimates below 20%. In addition, evidence of HIV/HCV co-infection among IDUs was found in 16 countries. In China, Poland, Puerto Rico, Russia, Spain, Switzerland, Thailand and Viet Nam, estimates of the prevalence of HIV/HCV co-infection among IDUs reached 90%. Taken together, data suggest high global prevalence of HCV and HIV/HCV co-infection among IDUs. We suggest exploring protective factors in sites of low HCV prevalence.

Designing studies to examine hepatitis C virus (HCV) transmission via the shared use of drug injection paraphernalia other than syringes is difficult because of saturation levels of HCV infection in most samples of injection drug users (IDUs). The authors measured the incidence of HCV infection in a large cohort of young IDUs from Chicago, Illinois, and determined the risk of HCV seroconversion associated with specific forms of sharing injection paraphernalia. From 1997 to 1999, serum samples obtained from 702 IDUs aged 18-30 years were screened for HCV antibodies; prevalence was 27%. Seronegative participants were tested for HCV antibodies at baseline, at 6 months, and at 12 months. During 290 person-years of follow-up, 29 participants seroconverted (incidence: 10.0/100 person-years). The adjusted relative hazard of seroconversion, controlling for demographic and drug-use covariates, was highest for sharing "cookers" (relative hazard = 4.1, 95% confidence interval: 1.4, 11.8), followed by sharing cotton filters (relative hazard = 2.4, 95% confidence interval: 1.1, 5.0). Risks associated with syringe-sharing and sharing of rinse water were elevated but not significant. After adjustment for syringe-sharing, sharing cookers remained the strongest predictor of seroconversion (relative hazard = 3.5, 95% confidence interval: 1.3, 9.9). The authors conclude that sharing of injection equipment other than syringes may be an important cause of HCV transmission between IDUs.

Hepatitis C (HCV) infection is common among injecting drug users (IDUs), yet accessing of HCV care, particularly HCV treatment, is suboptimal. There has been little in-depth study of IDUs experiences of what enables or prevents them engaging at every level of HCV care, including testing, follow-up, management and treatment processes. This qualitative study aimed to explore these issues with current and former IDUs in the greater Dublin area, Ireland. From September 2007 to September 2008 in-depth interviews were conducted with 36 service-users across a range of primary and secondary care services, including: two addiction clinics, a general practice, a community drop-in center, two hepatology clinics, and an infectious diseases clinic. Interviews were analyzed using a grounded theory approach. Barriers to HCV care included perceptions of HCV infection as relatively benign, fear of investigations and treatment, and feeling well. Perceptions were shaped by the discourse about HCV and "horror stories" about the liver biopsy and treatment within their peer networks. Difficulties accessing HCV care included limited knowledge of testing sites, not being referred for specialist investigations and ineligibility for treatment. Employment, education, and addiction were priorities that competed with HCV care. Relationships with health care providers influenced engagement with care: Trust in providers, concern for the service-user, and continuity of care fostered engagement. Education on HCV infection, investigations, and treatment altered perceptions. Becoming symptomatic, responsibilities for children, and wanting to move on from drug use motivated HCV treatment. In conclusion, IDUs face multiple barriers to HCV care. A range of facilitators were identified that could inform future interventions.