Hepatitis A
Hepatitis A is a virus that causes inflammation of the liver. In children, the infection often occurs without symptoms. This infection can result in jaundice (turning yellow), nausea and marked feelings of fatigue. In less than 1% of patients, liver failure can occur. Liver failure may resolve with medical care in about 50% of patients. Some patients may require liver transplantation when the amount of liver destroyed exceeds that required to maintain life.
Transmission
The transmission of hepatitis A occurs most commonly by contaminated water or food. Raw shellfish is a typical food that can transmit hepatitis A. Occasionally hepatitis A is transmitted by needles or other injections. Epidemics of hepatitis A occur in the U.S. and around the world. In some areas, such as the central valley of California, one may see a high frequency of hepatitis A infections over many months to years because of the migrant population.
Testing
There is a blood test to document current or recent hepatitis A infection (anti-HAV, IgM) and an additional test for past infection (anti-HAV, IgG). Chronic hepatitis is never caused by hepatitis A. The longest infection, with symptoms or jaundice, may last up to one year under very rare circumstances. Most patients' health improves within four to 16 weeks. Rest and nutrition are a very important part of the healing process because there are no medications that speed liver recovery. Herbal therapy has not shown any benefit. Prednisone should not be used to treat infections.
Precautions
When a patient has symptoms or jaundice due to hepatitis A, they must be considered very infectious. All patients should be carefully isolated in the hospital or at home. Patients should never share utensils or material that has had contact with body fluid, including towels.
Immune serum globulin should be used to prevent infection in close contacts and family members at a dose of 0.02 mL/kg. The globulin is given by injection and needs to be administered quickly after exposure (up to 10 days). A vaccine is available for hepatitis A. This vaccine, if administered in two injections about six to twelve months apart, protects more than 95% of patients. The vaccine is indicated when there is known exposure and for populations in high-risk geographic areas or for workers, such as daycare employees, who may be exposed to hepatitis A. People who use intravenous drugs and homosexuals should also be vaccinated, as well as travelers to third-world countries. The vaccine can be administered with immune serum globulin without affecting the response rate to either medication.