Hepatitis C infection is a major cause of chronic liver disease and death throughout the world. Hepatitis C virus (HCV) is transmitted by blood and now occurs primarily through injecting drug use. Transfusion-related HCV infection is rare since the introduction of routine screening of blood for HCV antibodies in the early 1990s.

Between 55% and 85% of those infected develop chronic infection and are at risk of progressive liver disease. Up to 20% of chronically infected individuals will develop cirrhosis of the liver over a 20 to 25 year period. Approximately 3% to 4% of patients with cirrhosis will develop hepatocellular carcinoma (HCC) per year.

There have been major advances in hepatitis C treatments in recent years with the arrival of direct acting antivirals which have been shown to achieve very high rates of viral clearance. The National Hepatitis C Database was set up in 2004 to collect data on people infected with HCV through the receipt of contaminated blood and blood products in Ireland.