Hepatitis A is a common viral infection of the gut, which then moves to infect the liver cells, multiplying inside them.
Hepatitis A infects the liver cells and multiplies inside them. As the body's immune system attempts to destroy the virus, the immune response causes liver cell damage and inflammation. Certain enzymes, usually active inside the liver cells, are released from damaged cells into the blood. Blood tests can detect them and thus confirm the presence of a hepatitis virus.
The swelling of the liver causes blockage of the bile ducts, trapping bile that should flow into the gall bladder inside the liver. The yellow-green bile being absorbed into the bloodstream from the liver causes the yellow discoloration known as jaundice. A health care professional will often be able to detect during examination of the abdomen that the liver is enlarged and tender.
Hepatitis A virus is common in all undeveloped parts of the world where it is mostly acquired by young children. The true burden of disease in South Africa is unknown. In highly developed countries, exposure to hepatitis A is low, with only 10% of adults being infected (also see ‘Prevention through vaccination’).
Revised and reviewed by Dr Karin Richter, MMed Path (Medical Virology), FC Path(SA) Viro, Dip HIV Man (SA), Dip Obst (SA), MBChB , Clinical Virologist, Senior Lecturer, Department of Medical Virology, University of Pretoria, Faculty of Health Sciences, and Consultant Pathologist, Tshwane Academic Division, National Health Laboratory Services (NHLS) February 2015.