Hepatitis C is a form of hepatitis, or 'inflammation of the liver,' caused by a virus known as the hepatitis C virus, or HCV. HCV infection is more common in Europe and the United States than HIV infection. The prevalence of hepatitis C virus infection is increasing worldwide. An estimated 3 percent of the world's people carry a virus that silently attacks their livers. About 4 million people in the United States have antibodies to HCV, meaning they have been infected with the virus at some point; as many as half of them do not know they have the infection. Most people infected with the hepatitis C virus (HCV) have no symptoms at all. In fact, most people don't know they have the disease until liver damage shows up, decades later, during routine medical tests. Chronic infection with this virus is one of the most important causes of chronic liver disease and the most common indication for orthotopic liver transplantation in most centers in the United States. Co-infection with HCV and HIV is a growing concern. Experts believe that 15 to 30% of HIV-positive people are also infected with HCV, but among injecting drug users and hemophiliacs, the rate can be as high as 90%.

The hepatitis C virus was identified in 1989 and it is estimated that three hundred million people worldwide have been infected with the virus. It is not related to hepatitis B virus, although it causes similar symptoms. HCV inhabits both the liver and the lymphatic system, and over time it may infect other organs too. Studies of blood donors suggest the prevalence of anti HCV antibodies is low in northern Europe, the USA and Australia, higher in southern Europe and Asia and highest in Africa.

Hepatitis C is an increasing public health concern in the United States and throughout the world.

• HCV is one of the most common causes of chronic liver disease in the United States and the most common cause of chronic viral hepatitis.
• It is believed to be the cause of about 15-20% of all cases of acute (new, short term) viral hepatitis and half of all cases of cirrhosis, end-stage liver disease, and liver cancer.

Hepatitis C has been referred to as a “silent epidemic.” Millions have the condition, but many of them are not aware of it because they may not experience symptoms for decades after they are infected. That’s a big reason why hepatitis testing and treatment are so important.

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