Hepatitis C virus (HCV) infection is a major cause of liver disease and death throughout the world. Between 55% and 85% of those infected develop chronic infection. It is estimated that up to 20% of those with chronic infection will develop cirrhosis of the liver over 20-25 years, with 3-4% of these developing hepatocellular carcinoma per year. Very effective treatments for HCV are now available which eradicate the virus in over 50% of cases depending on the genotype. The virus is transmitted by blood and now occurs primarily through injecting drug use. Transfusion-related HCV infection is rare now since the introduction of routine screening of blood in the early 1990s.

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. Approximately 1,700 people were infected through anti-D immunoglobulin, blood transfusion, blood clotting factors or treatment for renal disease. The purpose of the database project is to follow the natural history of infection, evaluate the outcomes of treatment, provide information for planning of services, and serve as a resource for research. This report is based on the fourth round of data collection and includes data on database participants up to the end of 2009.