Hepatitis D
Hepatitis D is a
virus that can only infect cells that are already infected with
hepatitis B. When this transmission occurs simultaneously, it is called
coinfection. When the hepatitis D virus infects cells previously infected with
hepatitis B, it is called
superinfection.
Either superinfection or coinfection can seriously worsen the damage to the liver caused by hepatitis B, causing cirrhosis or hepatocellular carcinoma (liver cancer).