What Is Hepatitis A?

Hepatitis A is a liver infection caused by the hepatitis A virus. Unlike hepatitis B and C, hepatitis A is very contagious and easily spread. Although the disease is usually mild and often doesn't require treatment other than monitoring the condition, in rare cases it can lead to serious problems, especially in the elderly and people who have compromised immune systems. A highly-effective vaccine is available to prevent the disease.

Misconceptions

• Hepatitis A is often confused with hepatitis B and hepatitis C. Although all three conditions are viral infections of the liver, hepatitis A is much less severe and much more contagious. Hepatitis B and C are primarily spread through risky behavior, much like HIV infection, although health care workers are also at risk from these conditions. Hepatitis A, on the other hand, is transmitted through contaminated food, water or being in close contact with an infected person.

Effects

• Not everyone who contracts hepatitis A has symptoms. Young children, especially, tend to have mild cases of the disease without ever having symptoms of infection. Older children and adults usually become ill from the disease, which may be mistaken for gastroenteritis (food poisoning, or "stomach flu"). The disease does not usually cause symptoms for the first month following infection. After the incubation period has passed, you may become fatigued, have nausea and vomiting, lose your appetite, have a low-grade fever, experience muscle aches and pains, have itchy skin and notice discomfort on the right side of your abdomen. Some people who have hepatitis A also develop jaundice, which causes the skin and whites of the eyes to turn a yellowish color and the urine to darken.

Identification

• Hepatitis A may be suspected based on a history of possible exposure and symptoms, but blood tests must be performed to confirm the diagnosis. The first blood tests performed are usually bilirubin and aminotransferase levels. Abnormal results indicate the liver is not functioning properly, which may be caused by hepatitis A. If one or both of these tests are positive, another blood test to check for the presence of antibodies to hepatitis A is performed. This test may be combined with others to check for conditions that cause liver problems. The false-negative rate from the antibody test is quite high if the test is performed soon after infection, and when antibodies are present, they may indicate a previous infection rather than the current illness. For this reason, it can be very difficult to be certain if a person has hepatitis A.

Prevention/Solution

• Hepatitis A can be prevented by having a series of immunizations against the disease. The hepatitis A vaccine requires two shots that are taken 6 to 12 months apart, and provides protection for up to 20 years. However, it does not work immediately; approximately 4 weeks must pass after the first injection for you to be protected. A short-term immunization, called immune globulin, can be used to prevent hepatitis A in people who are at risk. This immunization works almost immediately and lasts for approximately 3 months.

Warning

• Most cases of hepatitis A are not particularly serious and the liver does not sustain permanent damage. However, the elderly and people who have compromised immune systems or other serious health problems are at risk of liver damage or failure. Rarely, hepatitis A may lead to a condition called fulminant hepatitis. This condition is quite dangerous and can cause sudden liver failure. Those most at risk from fulminant hepatitis are people who have chronic liver disease or have had a liver transplant. There is no specific treatment available for hepatitis A, so people who have the condition usually receive supportive care. It is, however, very important to avoid drinking alcohol and taking medications that can cause liver damage during the illness.