Hepatitis A pathophysiology: what happens in the body

Hepatitis A is an infection caused by the hepatitis A virus. After entering the body, the virus travels through the bloodstream to the liver and uses liver cells to make more virus. The body’s immune system then recognises infected cells and mounts a response. Much of the liver irritation and the resulting rise in liver enzymes comes from this immune response rather than from direct destruction alone.

Inflammation can interfere with the liver’s normal handling of bile. This may contribute to yellowing of the skin or eyes and dark urine. Some people instead notice feeling generally unwell, nausea or loss of appetite. Hepatitis A does not usually become a long-term infection, but recovery can take time while the liver settles.

Arrange medical assessment if symptoms suggest hepatitis A or you have had a relevant exposure. A clinician may review your history, examine you and request a Liver Function Test; blood results help show how the liver is responding but are interpreted alongside other tests.

Rest when needed, drink fluids and choose small, manageable meals if nausea or poor appetite makes eating difficult. Avoid alcohol and check before taking medicines, supplements or herbal products because the inflamed liver may process them differently. Follow local hygiene advice, especially careful handwashing after using the toilet and before preparing food.

Seek prompt medical advice for jaundice, dark urine, persistent vomiting, worsening abdominal pain, marked drowsiness, confusion, bleeding or difficulty keeping fluids down. These features can signal significant illness or dehydration and should not be assessed by symptom frequency alone. Contact a clinician promptly if you are pregnant, have existing liver disease or have been exposed to someone with hepatitis A.

Ask which tests confirm the infection, whether your liver function needs repeat checks, which medicines and supplements to pause, and how long you should take precautions around food preparation and close contacts.