Hepatitis B and C in New South Wales prisons: prevalence and risk factors.

OBJECTIVES: To determine the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection among inmates entering the New South Wales correctional system and to examine risk factors for infection.

DESIGN: Cross-sectional survey.

SETTING: Reception Centre at Long Bay Correctional Centre, Sydney, New South Wales, June to December 1994.

PARTICIPANTS: 408 adult male inmates received at the Reception Centre (28% of the 1450 new inmates eligible for compulsory HIV testing).

OUTCOME MEASURES: Presence of HBV core and surface antibody and surface antigen; HCV antibody; risk factors; inmates' knowledge about risk factors.

RESULTS: 37% of inmates tested positive for HCV antibody, 31% for HBV core antibody and 3.2% for HBV surface antigen (indicating recent infection or carrier status). Among those who reported a history of injecting illegal drugs, rates rose to 66% for HCV antibody and 43% for HBV core antibody. Prevalence of HBV and HCV antibodies was similar in Aboriginal and non-Aboriginal inmates, but HBV antigen carrier rate was significantly higher among Aboriginals (12% versus 2.2%). Knowledge about hepatitis risk factors was poor (only 20% named injecting drug use), although recidivists were significantly better informed than those new to the correctional system. Multivariate analysis identified injecting drug use, past exposure to hepatitis B virus and previous imprisonments as significant predictors for HCV infection, and age over 25 years and HCV antibodies for HBV infection.

CONCLUSIONS: Results suggest that about a third of adult male prisoners entering the NSW correctional system may have been infected with HBV or HCV. Measures such as education about hepatitis risk factors and HBV vaccination are needed to reduce hepatitis transmission in this population.