Hepatitis C virus genotype differences seem to be of considerable clinical significance because they affect responses to antiviral therapy. HCV genotype 4 is rare in the United States and there are few published data regarding response to therapy in patients with HCV genotype 4 infection.
Division of Gastroenterology and Hepatology, Department of Internal Medicine, Saint Louis University School of Medicine, 3635 Vista Avenue, St. Louis, MO 63110, USA.