Hepatitis C - Risk Factors - Who gets Hepatitis C?

Who has it?

The World Health Organization estimates that 180 million people around the world (about 3% of the population) are infected with HCV. Although it affects members of all ethnic groups, hepatitis C appears to be more common in less industrialized areas of the world, with estimates as high as 20% of the population in some countries.

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), 4.1 million Americans (about 1.6% of the population) show evidence of having had an infection with HCV. Only about 25% of those individuals experienced symptoms that were attributed to hepatitis C, but 55% to 85% of them went on to the chronic phase. The Center for Disease Control estimates that there are 26,000 new infections each year, a decrease from the average of 240,000 per year in the 1980s. Most will develop chronic liver disease, which may progress to cirrhosis or liver cancer. In the 1970s and 1980s, a number of individuals got hepatitis C from donated blood that was contaminated with HCV, Today, the risk of transfusion-associated hepatitis C is very low (approximately one chance for every 100,000 units that are transfused). Approximately 25% of people who have HIV/AIDS will develop hepatitis C. Persons with HIV are more prone to get hepatitis C through sexual exposure.

What are the risk factors?

Mainly, HCV is passed from one individual to another through blood and blood products. A much smaller chance exists that it may also be transferred in bodily secretions, such as semen. The risk for infection with HCV is increased for individuals who:

• are born to mothers who have HCV
• had contact with high-risk individuals more than 6 months before the onset of symptoms
• have ever injected street drugs (even only once or many years ago)
• have HIV or AIDS
• have sexual contact with an infected individual
• live in poor socioeconomic conditions
• received transfusions of blood or blood products (especially before July 1992)
• require long-term kidney dialysis
• used blood-derived clotting factors before 1987
• work in health care facilities where they may be exposed to blood
• have liver disease

Illegal injection drug use accounts for about 60% of new HCV infections in the United States. In approximately 10% of infections, the source of exposure is unknown.