Incidence of primary hepatitis C infection and risk factors for transmission in an Australian prisoner cohort
1 School of Medical Sciences, The University of New South Wales, Sydney, New South Wales, Australia
2 National Drug and Alcohol Research Centre, The University of New South Wales, Sydney, New South Wales, Australia
3 Centre for Health Research in Criminal Justice, Justice Health, Sydney, New South Wales, Australia
4 Virology Division, SEALS, Prince of Wales Hospital, Sydney, New South Wales, Australia
5 The National Centre in HIV Epidemiology and Clinical Research, The University of New South Wales, Sydney, New South Wales, Australia
6 The Burnet Institute, Melbourne, Victoria, Australia
7 Drug Health Services, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
8 College of Health Science, Australian National University, Canberra, Australian Capital Territory, Australia
BMC Public Health 2010, 10:633 doi:10.1186/1471-2458-10-633Published: 22 October 2010
Hepatitis C virus (HCV) infection is common in prisoner populations, particularly those with a history of injecting drug use (IDU). Previous studies of HCV incidence have been based on small case numbers and have not distinguished risk events in prison from those in the community.
HCV incidence was examined in a longitudinal cohort of 488 Australian prisoners with a history of IDU and documented to be seronegative within 12 months prior to enrolment. Inmates were tested for anti-HCV antibodies and viremia, and interviewed about demographic and behavioral risk factors for transmission.
The cohort was predominantly male (65%) with high rates of prior imprisonment (72%) and tattooing (73%), as well as longstanding IDU (mean 8.5 years). Ninety-four incident HCV cases were identified (incidence 31.6 per 100 person years). Independent associations were observed between incident infection and prior imprisonment (p = 0.02) and tattooing (p = 0.03), and surprisingly also with methadone maintenance treatment (MMT) (p < 0.001).
High rates of new HCV infection were found in this prisoner cohort reflecting their substantive risk behavior profile, despite having remained uninfected for many years. The association with MMT is challenging and highlights the need for better understanding of prison-specific HCV transmission risks, as well as the uptake and effectiveness of prevention programs.