REVIEW Hepatitis C virus infection in the Middle East and North Africa ‘‘MENA’’ region: injecting drug users (IDUs) is an under-investigated population S. Ramia • N. M. Melhem • K. Kreidieh Received: 5 August 2011 / Accepted: 8 December 2011 / Published online: 12 January 2012 Ó Springer-Verlag 2011 Abstract Purpose Investigation of the injecting drug users (IDUs) population is becoming extremely critical and timely in light of the recent evidence that IDUs now act as the core of hepatitis C virus (HCV) epidemics in developed coun- tries. The purpose of this article, therefore, is not only to review the epidemiology of HCV in the Middle East and North Africa (MENA) region, but also to see whether IDUs were adequately studied and whether harm reduction strategies to be applied for their protection have been set. Methods A literature review was carried out of articles published within the last decade on HCV infection. Results The gathered data showed that the population of IDUs is severely under-investigated throughout the whole region, possibly due to religious and cultural impediments. Conclusion In order to reduce the risk of HCV infection in IDUs, a set of recommendations are advanced empha- sizing the urgent need for bio-behavioral studies in this population in order to help identify the source and mode of transmission and the genotypes of HCV involved. These results may allow the development of effective and, yet, socially acceptable intervention strategies. We believe that the role which IDUs play in sustaining HCV infection is also an under-investigated topic in many developing countries. Similar reviews and, hence, interventions should be initiated in these regions. Keywords Hepatitis C virus Á Middle East Á North Africa Á Injecting drug users Introduction Hepatitis C virus (HCV) infection, caused by an enveloped single-stranded positive-sense RNA virus of the Flaviviri- dae family [1], is now recognized as a major public health problem worldwide, infecting over 170 million people around the world [2]. Among acute HCV infections, 15–20% of the patients recover spontaneously, but in the overwhelming majority of cases, the disease runs a chronic course and might lead into cirrhosis of the liver and hepatocellular carcinoma (HCC), both of which are fatal [3, 4]. Before the introduction of diagnostic blood screening in the early 1990s, HCV was mainly transmitted through blood, blood products, hemodialysis, and organ transplan- tation [5, 6]. The current availability of highly sensitive and specific blood screening tests and the strict adherence to universal safety precautions in health care settings led to a reduction in the transmission of HCV through exposure to infected blood such that it is now minimal [7, 8]. HCV infection is now primarily transmitted by parenteral expo- sure through the sharing of needles or other injecting equipment [9, 10]. This is particularly obvious in the Western world, where illegal injecting drug use has been the dominant mode of HCV transmission [11, 12]. More- over, the duration and frequency of injecting drug use, sharing equipment, and having served a prison sentence are among the main factors associated with an increased risk of HCV infection [13, 14]. The focus of this review, however, is to review the epidemiology of HCV in the Middle East and North Africa (MENA) region and, more importantly, to highlight the urgent need to study HCV infection in injecting drug users (IDUs), a high-risk subpopulation which remains under- investigated throughout the whole MENA region. This is S. Ramia (&) Á N. M. Melhem Á K. Kreidieh Medical Laboratory Sciences Department, Faculty of Health Sciences, American University of Beirut, P.O. Box 11-0236, Riad El-Solh, Beirut, Lebanon e-mail: sramia@aub.edu.lb 123 Infection (2012) 40:1–10 DOI 10.1007/s15010-011-0236-z