Changing pattern of hepatitis C virus spread in rural areas of Egypt Naglaa Arafa 1 , Mostafa El Hoseiny 1 , Claire Rekacewicz 2 , Iman Bakr 1 , Sherif El-Kafrawy 3 , Mai El Daly 3 , Saeed Aoun 4 , Diaa Marzouk 1 , Mostafa K. Mohamed 1 , Arnaud Fontanet 2, * 1 Department of Community, Environmental and Occupational Medicine, Faculty of Medicine, Ain Shams University, Cairo, Egypt 2 Emerging Disease Epidemiology Unit, Institut Pasteur, Paris, 28 rue du Docteur Roux, Paris, France 3 National Hepatology and Tropical Medicine Research Institute, Cairo, Egypt 4 Department of Communicable Diseases, Ministry of Public Health, Egypt Background/Aims: To identify patterns of HCV spread in the Nile Delta of Egypt. Methods: Residents in a Nile Delta village were invited to participate in a cohort study of HCV infection. Risk factors for past or current infection were identified at cohort intake using generalized estimated equations models. Attributable fractions were calculated for all independent risk factors. Results: The prevalence of HCV antibodies increased from 2.7% in those !20 years of age to more than 40% in males aged 40–54 years. The peak in HCV prevalence in the 40–54 year age group corresponds to the aging of the cohort of children infected through schistosomiasis intravenous treatments in the 1960s-70 s (accounting for 12.4% of all HCV infections observed today among adults). Following this initial founding event, the HCV epidemic has spread in the community through iatrogenic factors, and particularly injections (37.9% of the overall attributable fraction in adults). In children, however, no iatrogenic factors were associated with increased risk of infection, suggesting a change in the pattern of HCV spread. Conclusions: While HCV infections in adults could be attributed to iatrogenic factors, and particularly injections, infections in children could not be explained by similar routes of transmission. q 2005 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved. Keywords: HCV; Risk factors; Iatrogenic; Epidemiology 1. Introduction Hepatitis C virus (HCV) antibody prevalence in Egypt was estimated around 12% nationwide in 1999 (Egypt Ministry of Health and Population, 1999). The origin of the epidemic has been attributed to mass campaigns of parenteral anti-schistosomiasis treatment (PAT) in rural areas in the 1960s-70 s [1]. Treatment consisted of several (up to 12) intravenous (IV) injections of tartar emetic spaced by one week and it is postulated that transmission occurred due to insufficient sterilisation of injection equipment between subjects. During these treatment campaigns, the target population was anyone living in schistosomiasis-endemic areas, and particularly children and young boys who were treated while at school. This mode of HCV transmission stopped after 1982 when oral praziquantel was introduced for schisto- somiasis treatment. HCV spread continued however, and it would be useful for on-going prevention programs to have data on current risk factors for transmission. To study HCV incidence rate and related risk factors, we initiated a cohort study in a rural area of Egypt where schistosomiasis treatment campaigns took place in the 1960s-70 s. HCV antibody prevalence and risk factors at the cohort intake are presented here. Journal of Hepatology 43 (2005) 418–424 www.elsevier.com/locate/jhep 0168-8278/$30.00 q 2005 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved. doi:10.1016/j.jhep.2005.03.021 Received 27 December 2004; received in revised form 9 March 2005; accepted 17 March 2005; available online 31 May 2005 * Corresponding author. Tel.: C33 1 4061 3763; fax: C33 1 4568 8876. E-mail address: fontanet@pasteur.fr (A. Fontanet).