What is hepatitis B for?

The virus can cause a short-term illness or remain in the body and continue affecting the liver. Some people have no symptoms. Others may notice fatigue, nausea, discomfort under the ribs, yellow skin or eyes, or dark urine. Infection can spread when infected blood or certain body fluids enter another person's body, including through sexual contact, shared injecting equipment, or contact with blood during birth. It does not spread through ordinary casual contact such as sharing a room.

If you may have been exposed, ask a clinician about blood testing rather than trying to judge from symptoms. A liver function test can show whether the liver is under stress, but it does not by itself confirm or exclude hepatitis B. Vaccination can prevent infection and is especially relevant when exposure risk is higher. Do not share razors, toothbrushes or injection equipment, cover bleeding wounds, and use condoms until a clinician has explained your results and protection options.

Arrange prompt medical advice after a possible blood or body-fluid exposure, during pregnancy if infection is possible, or when symptoms such as jaundice, dark urine, persistent vomiting or worsening fatigue appear. Seek urgent help for confusion, severe abdominal pain, bleeding, or inability to keep fluids down. A lack of symptoms does not rule out infection, so testing may still be appropriate.

Ask which blood tests are suitable, whether your vaccination record is complete, whether household or sexual contacts need testing, and when results should be reviewed. Ask how to protect your liver while the assessment is underway.