An inflammation of the liver caused by certain viruses and other factors such as alcohol abuse, some medications and trauma. Although many cases of hepatitis are not a serious threat to health, the disease can become chronic and can sometimes lead to liver failure and death. There are four major types of viral hepatitis: (a) hepatitis A, caused by
infection with the hepatitis A
virus; (b) hepatitis B, caused by
infection with the hepatitis B
virus (HBV), which is most commonly passed on to a partner during intercourse, especially during anal sex, as well as through sharing drug needles; (c) non-A, non-B hepatitis, caused by the hepatitis C
virus, which appears to be spread through sexual contact as well as through sharing drug needles (another type of non-A, non-B hepatitis is caused by the hepatitis E
virus, principally spread through contaminated water) (d) delta hepatitis occurs only in people who are already infected with HBV and is caused by the HDV
virus; most cases of delta hepatitis occur among people who are frequently exposed to blood and blood products such as people with
hemophilia. See also
Hemophilia.