Response to HBV vaccine in relation to anti-HCV and anti-HBc positivity: a study in intravenous drug addicts F. Minniti a , V. Baldo b , R. Trivello b , R. Bricolo c , L. Di Furia c , G. Renzulli d , M. Chiaramonte a, * a Department of Gastroenterology, University of Padua, Via Gustiniani 2, I-35100 Padua, Italy b Institute of Hygiene, University of Padua, Padua, Italy c Service for assistance to IVDUs (SERT) of Padua Local Health Unit, Padua, Italy d Public Health Department, Padua Local Health Unit, Padua, Italy Received 6 July 1998; received in revised form 9 March 1999; accepted 16 March 1999 Abstract Drug addicts represent the group of young adults with the lowest response to hepatitis B virus (HBV) vaccine. A study was carried out on 110 current intravenous heroin users attending the service providing assistance to intravenous drug users (IVDUs) (SERT) in Padua: 66.4% of them were found anti-hepatitis C virus (HCV)-positive and 33.6% were anti-HBc positive; 29.9% were positive for both. The subjects were vaccinated with 10 mg of yeast-derived vaccine at months 0, 1 and 2 (fast schedule). The overall response rate was 66.4%. Response seems to be aected by positivity to anti-HBc, but not to HCV infection. # 1999 Published by Elsevier Science Ltd. All rights reserved. Keywords: HBV vaccine; IVDUs; Anti-HBc 1. Introduction Infection with hepatitis B virus (HBV) is frequent among intravenous drug users (IVDUs), a group at a high risk of parenterally-transmitted infections. Prophylaxis with hepatitis B vaccination has been rec- ommended for such people [1]. Several studies have addressed the problem of low response to vaccination in IVDUs, however. The lack of anti-HBV response in vaccinated subjects may be due to HIV seropositivity and the immunosuppressive eect of multiple drug abuse [2±4]. Moreover, IVDUs are very frequently infected with hepatitis C virus (HCV) [5,6]. The eect of HCV infection on response to HBV vaccine is still debated. A recent study in haemodialysed patients [7] suggests that HCV infection can lower the eectiveness of hepatitis B vaccine. IVDUs also show anti-HBc positivity more frequently than the general population of the same age [8]. Response to HBV vaccine in anti- HBc-positive subjects has yet to be established and can range from a booster-response to an absolute non-re- sponse [2,3,9]. This paper examines vaccine responsive- ness to primary vaccination in relation to HCV infection and/or anti-HBc positivity in a group of active IVDUs with a high prevalence of anti-HCV and/or anti-HBc. 2. Materials and methods The study was carried out on a group of 110 current intravenous heroin addicts (90 males and 20 females; mean age 39.526.3 years) attending the service provid- ing assistance to IVDUs (SERT) in Padua. All subjects enrolled for the study were HIV-negative and sero- Vaccine 17 (1999) 3083±3085 0264-410X/99/$ - see front matter # 1999 Published by Elsevier Science Ltd. All rights reserved. PII: S0264-410X(99)00143-7 ww.elsevier.com/locate/vaccine * Corresponding author. Tel.: +39-49-8212864; fax: +39-49- 8760820.