Hepatitis is inflammation of the liver. Infection with hepatitis C virus (HCV) is 1 of the most common causes of hepatitis in the United States. New infection causes liver inflammation. In some patients, the inflammation resolves without treatment; in others, the inflammation does not resolve. It may stay active for a long time, slowly causing liver damage. The liver damage may progress to severe liver scarring (cirrhosis), liver failure, liver cancer, or death. Treatment of the infection can slow this progression. However, not all people respond to the treatment, and treatment has never been shown to prevent the complications of chronic infection.