Hepatitis A is a viral infection that can inflame and damage the liver. Unlike other forms of hepatitis, hepatitis A is usually mild and does not last long. Usually spread in contaminated food or water, hepatitis A also can be passed during sexual practices that involve the anus. In rare cases, hepatitis A can be spread by contact with the blood of a person who has the infection, for instance, when intravenous drug users share needles.
About 30% of people in the United States have been exposed to hepatitis A, but only a very small number of them develop symptoms from the disease. Americans most likely to get hepatitis A include:
People who eat shellfish taken from waters where raw sewage drains
Children and caregivers in daycare centers who are exposed to the stool of an infected child