Prevalence of hepatitis and HIV infections and vaccination rates in patients entering the heroin-assisted treatment in Switzerland between 1994 and 2002

Abstract
Hepatitis C virus (HCV) remains very prevalent in injection drug users (IDUs). In spite of recommended vaccinations against hepatitis A virus (HAV) and hepatitis B virus (HBV), many IDUs remain susceptible to HAV and HBV. Patients entering heroin-assisted treatment between 2000 and 2002 (N = 210) were compared for infectious disease status with patients entering this treatment in 1998 (N = 243) and between 1994 and 1996 (N = 1035). Infection status was determined with the aid of questionnaires and blood tests for antibodies against HAV, HBV core antigen, HCV and HIV. In the cohort 2000–2002 78.3% of the patients were HCV positive, 53.3% were HBV positive, 41.2% were HAV positive and 12.6% were HIV positive. In comparison to the cohorts entering the heroin- assisted treatment at an earlier time, there was a significant reduction of HBV and HAV infections, but not of HCV and HIV infections. 15.6% of the patients entering between 2000 and 2002 were vaccinated against HBV and 10.3% against HAV. 31.1% of patients at entrance were susceptible for HBV and 48.5% for HAV. In comparison to patients entering treatment in 1998 there was no significant increase in patients who were vaccinated against HBV. This data illustrates the need for improving HCV prevention and more consequent vaccination against HBV and HAV in IDUs.