Resat Ozaras, MD, Professor is in Infectious Diseases Department of Cerrahpasa Medical School, Istanbul University, Turkey. He studies acute hepatitis and chronic hepatitis of B, C, and D. He is a member of Viral Hepatitis Study Group of European Society of Clinical Microbiology and Infectious Diseases (ESCMID).Veysel Tahan, MD, FACP, FACG, FEBSGH, is an Associate Professor who is currently a clinical faculty at the University of Missouri, Division of Gastroenterology and Hepatology at Columbia, Missouri, USA. He is an American College of Gastroenterology (ACG) mentor and a fellow of ACG, the American College of Physicians (ACP), and the European Section and Board of Gastroenterology and Hepatology. Dr. Tahan is an active member of multiple scientific societies, including the American Association for the Study of Liver Diseases, the Cell Transplant Society, the American Gastroenterology Association, the American Society for Gastrointestinal Endoscopy, the European Board of Gastroenterology, and the Turkish Society of Gastroenterology.