Hepatitis D, also called delta virus, is a defective virus that requires the helper function of the hepatitis B virus to multiply and is therefore only found in people who are infected with hepatitis B. Hepatitis D is the least common but most severe form of viral hepatitis. Worldwide the pattern of hepatitis D infection is similar to the occurrence of hepatitis B infection and it has been estimated that 15 million people with hepatitis B (HBsAg+) are infected with hepatitis D.  Hepatitis D is not a common infection in Australia. Over the past 6 years there have been between 20 and 30 cases of hepatitis D diagnosed and reported each year. The symptoms of hepatitis D are similar to hepatitis B, such as:

loss of appetite
nausea and vomiting
tiredness
pain in the liver (upper, right side of abdomen)
muscle and joint pain
jaundice (yellowish eyes and skin, dark urine and pale-coloured faeces. (CDC 2006)

People who are infected with hepatitis D and hepatitis B have a higher risk of developing chronic liver disease and cirrhosis (scarring of the liver).