Hepatitis

Hepatitis, inflammation of the liver, caused by a virus. The symptoms include fever, nausea, loss of appetite, and jaundice. At least two distinct forms of the disease are recognized. Hepatitis A (formerly called infectious, or epidemic, hepatitis) is spread by contaminated drinking water or food. In young children, the infections tend to be mild, but the clinical severity increases with the age of the patient. Hepatitis B (formerly called serum hepatitis) is usually transmitted by transfusions of infected blood or blood products. It is particularly common among intravenous drug users, who may use contaminated needles. The Hepatitis B virus has been detected in a variety of body secretions, including saliva, sperm, and vaginal fluid, and may be transmitted by some forms of sexual contact. Exposure to hepatitis B usually results in an acute self-limiting infection with mild symptoms. In adults, 5–15% of infections fail to resolve, and the affected individuals become persistent carriers of the virus, which is responsible for many cases of liver cancer. There is a vaccination against hepatitis B, which was approved for use in the United States in 1982. In recent years, a third form of the disease, sometimes called hepatitus C, has been detected. Its cause is not known.

See also: Liver.