Hepatitis A is caused by a virus. The illness may be mild, lasting a week or two. It may be more severe, lasting about one month. In general, severity increases with age, or adults may be more ill than children. Most people recover completely without permanent damage.
Symptoms occur from two to six weeks, usually a month, after exposure.
Illness begins suddenly, usually with fever, chills, loss of appetite, nausea, extreme tiredness, and stomach pain. Infections may be mild and without jaundice, especially in children. Sometimes there are no symptoms at all. The doctor will look at a person's signs and symptoms, and do a blood test to check the liver and test for hepatitis. This means people become infected when they eat food prepared by someone shedding the virus in their stools who didn't wash their hands after using the bathroom.