Original article Descriptive epidemiology of chronic hepatitis B by using data from a hepatitis registry in Central Greece Aggelos Stefos a , Nikolaos Gatselis a , Kalliopi Zachou a,b , Eirini Rigopoulou a,b , Christos Hadjichristodoulou c , George N. Dalekos a,b, ⁎ a Department of Medicine, Academic Liver Unit, Medical School, University of Thessaly, Larissa, Greece b Institute of Biomedical Research and Technology, Centre for Research and Technology-Thessaly (CE.RE.TE.TH), Larissa, Greece c Department of Hygiene and Epidemiology, Medical School, University of Thessaly, Larissa, Greece Received 22 August 2007; received in revised form 18 March 2008; accepted 25 April 2008 Available online 17 June 2008 Abstract Background: In Greece, there are few data on the epidemiological characteristics of HBV. Our aim was to study the epidemiological patterns of HBV in Central Greece and identify the possible differences in HBV prevalence (clusters) among areas inside this region using data from the hepatitis registry. Methods: The study was performed in Thessaly, one out of the thirteen regions of Greece and covers most of the part of Central Greece. A total of 921 HBV patients were registered in the hepatitis registry during the period 1999–2004 while 303 were randomly selected to be studied further using a detailed questionnaire on several epidemiological factors. Results: 187/303 patients (61.7%) classified as chronic inactive HBV carriers, 78/303 (25.7%) had chronic hepatitis B, 29/303 (9.6%) had HBV- related cirrhosis and 9/303 (3%) HBV-related hepatocellular carcinoma (HCC). The route of HBV transmission was vertical in 103 (34%), sexual in 46 (15.1%) and intrafamilial in 98 (32.4%). Folk remedies were identified as the predisposing risk factor for contracting HBV infection in 38 (12.5%), previous transfusion in 9 (3%) and unknown mode of transmission in 9 patients (3%). Alcohol abuse was the only independent factor (OR: 2.5; p = 0.01) associated with the progression to cirrhosis–HCC. There were specific areas (clusters) inside Thessaly region with increased ratio of HBV infection; Vertical and sexual modes of transmission were more prominent in some of these areas. Conclusions: Vertical, intrafamilial and sexual modes of HBV transmission identified as the major routes of HBVinfection in our study. We also identified cluster areas of HBV infection in Central Greece. Alcohol abuse is frequent among HBV patients and is acting as an effect modificator risk factor for the development of HBV-related cirrhosis and HCC. Extended population studies in Greece are needed to assess in detail the epidemiological patterns of HBV and evaluate control programmes. © 2008 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved. Keywords: Hepatitis B virus; Alcohol consumption; Cirrhosis; Epidemiology; Modes of transmission; Public health 1. Introduction Hepatitis B virus (HBV) infection is a major public health problem and a cause of infectious disease mortality worldwide. It has been estimated that there are 350 million chronic HBV carriers all over the world. Approximately 1 million people die annually from HBV-related liver disease, including cirrhosis and hepatocellular carcinoma (HCC) [1]. The epidemiology of HBV infection varies greatly in different parts of the world and is influenced primarily by the predominant age at which the infection occurs [1]. In Greece, selective vaccination of high-risk groups was initiated in 1982. A national preventing programme against HBV infection including universal screening of pregnant women with immediate vaccination (birth dose of hepatitis B vaccine) of European Journal of Internal Medicine 20 (2009) 35 – 43 www.elsevier.com/locate/ejim ⁎ Corresponding author. Academic Liver Unit and, Research Laboratory of Internal Medicine, Medical School, University of Thessaly, Papakiriazi 22 str, 41222 Larissa, Greece. Tel.: +30 2410 565251; fax: +30 2410 565250. E-mail address: dalekos@med.uth.gr (G.N. Dalekos). 0953-6205/$ - see front matter © 2008 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved. doi:10.1016/j.ejim.2008.04.023