Hepatitis D (also known as Delta Hepatitis) can only occur where hepatitis B is present. This can be by simultaneous infection, or infection with hepatitis D in a person who is already hepatitis B positive. Co-infection with these two viruses can speed up progression of liver disease. Transmission of hepatitis D is similar to hepatitis B; that is through blood and sexual fluids.
Hepatitis E is transmitted via the faecal-oral route, as for hepatitis A. Infection generally lasts for a couple of weeks and has not been known to develop into chronic illness.
The only other form of hepatitis known to date is hepatitis G. As it was only identified recently, there is little research on outcomes at this stage. Chronic infection has been reported, however long-term outcomes are still being researched. Co-infection with hepatitis A, B and C can also occur. No vaccine has been developed.
Hepatitis D, E and G are extremely rare in Australia.
Care must be taken to avoid these, as well as other illnesses, when visiting risk-prone areas such as parts of India, Africa, Central America and Asia.
