Iranian Red Crescent Medical Journal REVIEW ARTICLE HIV/HBV Co-Infections: Epidemiology, Natural History, and Treatment: A Review Article R Ranjbar1, A Davari 1 , M Izadi2, N Jonaidi2, SM Alavian 3 * 1Molecular Biology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran 2Health Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran 3Baqyiatallah Re- search Center for Gastroenterology and Liver Disease, Baqiyatallah University of Medical Sciences, Tehran, Iran Abstract Hepatitis B virus (HBV) infection, one of the major health priorities, accounts approximately for 350 million chron- ic cases and a global total of 33 million people were living with human immunodeficiency virus (HIV) in the world. Co-infection with HIV and the HBV presents a significant challenge to health care providers, with different preva- lence rates in different parts of the world. It is important to screen all HIV infected individuals for HBV infection and reverse. Infection with HBV becomes more violent in patients co-infected with human immunodeficiency syndrome. HIV/HBV co-infected individuals are at increased risk of chronic hepatitis, cirrhosis, and hepatocellular carcinoma, and of experiencing HAART toxicity. In this review, the latest statistics on epidemiology of HIV, HBV and their co-infection has been presented along with prominent characteristics of HBV. Transmission routes which are the common between HBV and HIV are described and the most important ones are described accord- ing to the regional and age features. Also, there is a series of actions being performed once HBV infections occur to prevent HIV or to diagnose if the HBV-infected individuals are also infected with HIV. As in treatment case, some of the frequent treatment methods including applying interferon and using nucleoside and nucleotide ana- logues have been discussed. Finally, we would explain the new recommendations for treating patients who were co-infected with HBV and HIV, including staging HBV and HIV treatment, based on the stage of each disease. It also outlines the optimal treatment options, whether the patient is treated for HBV first, HIV first, or HIV and HBV together. Keywords: HIV; Hepatitis B; Co-infection; Acute; Chronic; Epidemiology Latest Courses in Epidemiology Hepatitis B, one of the major health priorities, ac- counts approximately for 350 million chronic cases out of 2 billion people infected worldwide.1 An esti- mated 600,000 people die each year because of the acute or chronic consequences of hepatitis B. Human immunodeficiency virus (HIV) is one of the other viruses in charge of infectious diseases. A global total of 33 million (30.6–36.1 million) people were living with HIV from which 2.7 million (2.2–3.2 million) individuals were newly infected in the late 2008 and 2.0 million (1.8–2.3 million) died of AIDS-related illnesses in 2007 (Table 1).2 Infection with HBV as *Correspondence: Seyed-Moayed Alavian, MD, Baqyiatallah Re- search Center for Gastroenterology and Liver Diseases, Baqiyatal- lah University of Medical Sciences, Mollasadra Ave, Vanak Sq, PO Box: 14155/3651, Tehran, Iran. Tel/Fax: +98-21-88945186-8, e-mail: alavian@thc.ir Received: April 10, 2011 Accepted: August 10, 2011 well as HIV infection is one of the major concerns globally. Co-infection with the HIV and the hepatitis B virus (HBV) presents a significant challenge to health care providers, with different prevalence rates in different parts of the world and in average affecting approximately 10% of persons with HIV infection.3 HBV and HIV share the common mode of transmis- sion; thus co-infection of these two viruses occurs frequently.4,5 Despite the high rate of co-infection, the correlation between HBV and HIV mostly depends on the affected community as well as transmission route. In Iran as an instance, HBV alone has been transmitted vertically and most HBV affected indi- viduals were nevertheless HIV negative.6,7 Routes of transmission can be characterized by the geographical origin of infected patients as in low HBV prevalence ≤2% HBsAg - in USA, Western Europe, Australia, and New Zealand which is mostly caused by drug Iran Red Crescent Med J 2011; 13(12):855-862 ©Iranian Red Crescent Medical Journal