Not everyone who is infected with HAV will experience noticeable symptoms. For example, many babies and young children infected with HAV do not experience any symptoms of infection. Symptoms are much more likely to occur in older children, adolescents and adults.
Symptoms of hepatitis A (and acute hepatitis in general) can include:
Yellowing of the skin, whites of the eyes and under the fingernails (jaundice)
Feeling tired and rundown (fatigue)
Pain in the upper-right abdomen
Loss of appetite
Dark urine and/or pale stool
HAV infection can also cause enzymes produced by the liver to increase above normal levels in the bloodstream. The most important liver enzymes are alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Elevated enzyme levels indicate that the liver is not functioning properly and that there may be a risk of permanent liver damage. With hepatitis A, liver enzyme levels can be temporarily elevated, but this rarely leads to long-term liver problems.
It can take the immune system up to eight weeks to clear HAV from the body. If symptoms occur, they usually do so within two to four weeks after being infected. The symptoms of hepatitis A can last anywhere from a week to more than a month. About 15 percent of people with hepatitis A experience symptoms that last between six to nine months.
About one out of 100 people infected with HAV may experience a quick and severe (fulminant) infection that, very rarely, can lead to liver failure and death.