The outcome of a rapid hepatitis B vaccination programme in a methadone treatment clinic

Abstract

Injecting drug users are a high-risk population for hepatitis B (HBV), but are difficult to engage in vaccination programmes. This study examines the completion rates of a HBV vaccination schedule and seroconversion in a group of patients in methadone maintenance treatment. Patients at a public methadone maintenance programme in Sydney, Australia, were screened for viral hepatitis (hepatitis A, B and C) and offered a rapid HBV vaccination schedule (0, 1 and 2 months). Hepatitis B surface antibody (antiHBs) was retested on completion of the vaccination schedule. A total of 143 patients [71.3% male, mean age 33.1 (standard deviation +/- 8.3)] enrolled in the project. Forty-nine per cent of patients were HAV antibody (Ab) positive, 81.1% hepatitis C virus (HCV) antibody (Ab) positive and 38.9% antiHBs positive. Exposure to multiple hepatitis viruses was common, with 24.5% testing positive for all three viruses. Seventy-three (83%) of the 88 antiHBs negative patients completed the vaccination schedule. Post-vaccination serology indicated a seroconversion rate of 75.4% (55 of 73) of completors, or 62.5% of eligible participants (55 of 88). While there was a high rate of completion of the rapid vaccination schedule in this population, a moderate seroconversion rate was achieved. Further work is required to identify an optimal vaccination schedule in opioid substitution patients.