Which hepatitis virus requires the presence of hepatitis B for replication?

• A. Hepatitis A
• B. Hepatitis C
• C. Hepatitis D
• D. Hepatitis E

Answer: (C)

Hepatitis D is a defective RNA virus that cannot form infectious particles on its own and must borrow the hepatitis B surface antigen to envelope its genome. This means it can only replicate and spread in people who have hepatitis B infection, either at the same time (coinfection) or if someone with chronic HBV acquires HDV (superinfection). In contrast, hepatitis A and E are nonenveloped viruses that replicate independently and are transmitted mainly by the fecal-oral route, while hepatitis C is an enveloped virus that replicates without requiring any helper virus. So the virus that requires hepatitis B for replication is hepatitis D.