Irritation of the liver that sometimes causes permanent damage. Hepatitis may be caused by viruses or by medicines or alcohol. Hepatitis has the following forms:
Hepatitis A: A virus most often spread by unclean food and water.
Hepatitis B: A virus commonly spread by sexual intercourse or blood transfusion, or from mother to newborn at birth. Another way it spreads is by using a needle that was used by an infected person. Hepatitis B is more common and much more easily spread than the AIDS virus and may lead to cirrhosis and liver cancer.
Hepatitis C: A virus spread by blood transfusion and possibly by sexual intercourse or sharing needles with infected people. Hepatitis C may lead to cirrhosis and liver cancer. Hepatitis C used to be called non-A, non-B hepatitis.
Hepatitis D (Delta): A virus that occurs mostly in people who take illegal drugs by using needles. Only people who have hepatitis B can get hepatitis D.
Hepatitis E: A virus spread mostly through unclean water. This type of hepatitis is common in developing countries. It has not occurred in the United States.

