Chronic HCV infection. Epidemiology and clinical relevance

Hepatitis C virus (HCV), first recognized as a cause of transfusion-associated acute and chronic hepatitis in 1989, plays a major role as a cause of chronic liver injury, with potential for neoplastic degeneration. It is mainly transmitted by the parenteral route. However, although with lower efficiency, it may be also transmitted by sexual intercourses and by the mother-to-child route. Epidemiological evidence shows that a wave of infection occurred in the 1945-65 period (baby boomers) in western countries. After acute infection, as many as 50-85% of the patients fail to clear the virus resulting in chronic liver infection and/or disease. It is estimated that, on a global scale, about 170 million people are chronically infected with HCV, leading to about 350.000 deaths yearly. Among western countries southern Europe, and particularly Italy, is among the most affected areas. The impact on the public health systems is noteworthy, with high number of hospitalizations due to chronic liver disease, cirrhosis or hepatocellular carcinoma. While waiting for a safe and effective vaccine to be made available, new promising direct-acting antiviral (DAA) drugs offer a better therapeutic scenario than in the past even for the poor responder genotypes 1 and 4, provided that effective screening and care is offered. However, the long and aspecific prodromic period before clinical symptoms develop is a major obstacle to early detection and treatment. Effective screening strategies may target at-risk groups or age specific groups, as recently recommended by the CDC