The symptoms of hepatitis D are similar to hepatitis B monoinfection. In a recent (acute) infection, there are often no symptoms. It can cause mild flu-like symptoms, pale stools, dark urine, fever or yellowing of the skin and/or eyes.

In chronic infection, most people have no symptoms until they develop cirrhosis or liver cancer. The most common symptom of chronic hepatitis B and D is fatigue.

A hepatitis D diagnosis can only be made if there are also hepatitis B surface antigen (HBsAg) present. HBsAg is the outer surface, or ‘envelope’, of the hepatitis B virus. The delta virus needs this to reproduce.

If hepatitis D is suspected, then a test for antibodies would be performed. If the test is positive, then a PCR test for hepatitis D antigen is required to distinguish between an infection that is currently active and one that has been cleared. This test is only available in a few specialised laboratories.