Hepatitis D

Hepatitis D (HDV) can co-infect at the time of infection with Hepatitis B (HBV) (e.g via a needle stick injury from a co-infected patient ). As the pathogenicity of combined HBVHDV co-infection far exceeds that of HBV, the downside risk of needlestick injury related to such patients is significantly higher. There are also fewer treatment options.

Hepatitis D virus is a virus that requires co-infection with HBV virus for its replication. At least 5% of people with chronic HBV infection are co-infected with HDV. there are about 10-20 million infections worldwide probably. This figure is decreasing in concert with HBV vaccination:The HBV vaccine protects against HDV as HDV can only co-infect with HBV. Worldwide, the overall number of HDV infection is decreasing. This due to a successful global HBV vaccination programme. HDV augments the pathogenicity of HBV. Mortality is 20%. HDV-HBV co-infection carries the highest mortality of the viral hepatitis infections with due to more rapid progression towards liver-related death and hepatocellular carcinoma. Treatment success rates are low, but Hepatitis D infection can be prevented by Hepatitis B immunization. Vertical transmission is not common but transmission via birth trauma or contact with contaminated tissue occurs in concert with HBV does occur. Hepatitis E is unrelated to HDV. Hepatitis E pathogenesis compares with Hepatitis A. Hepatitis E is not a co-infection with Hepatitis A.