On the cover: An artist rendering of the hepatitis C virus (HCV). HCV belongs to the Hepacivirus genus of the Flaviviridae family. HCV virions consist of a lipid bilayer formed by envelope glycoproteins (E1 and E2); the envelope surrounds the nucleocapsid, which is composed of HCV core protein and contains the positive-strand RNA genome of approximately 9.6 kb. After exposure to HCV, the first viral marker detectable in blood 1–2 weeks after infection is HCV RNA; another viral marker, HCV core antigen (HCV cAg) is detectable 2–3 weeks after infection. Antibodies to HCV can be detected an average of 7–8 weeks after infection and persist for life. Antibodies to HCV indicate current or past-resolved infection, diagnosis of current HCV infection requires detection of a viral marker, HCV RNA or HCV cAg.