In hepatitis D infection, which statement is correct?

In hepatitis D infection, which statement is correct?

• A. HDV requires concomitant HBV infection
• B. HDV occurs independently of HBV
• C. HBV vaccination does not affect HDV risk
• D. HDV reduces risk of liver cancer

Answer: (A)

HDV is a defective virus that cannot form its own outer shell and must borrow the hepatitis B surface antigen (HBsAg) to assemble infectious particles. Because of this, HDV infection can occur only in the setting of active HBV infection—either at the same time as HBV enters (coinfection) or later in someone who already carries HBV (superinfection). Vaccination against HBV prevents HBV infection and, by eliminating HBsAg, removes the necessary component for HDV to assemble, thereby reducing HDV risk. Conversely, HDV infection tends to accelerate liver disease and increases the risk of progressing to cirrhosis and hepatocellular carcinoma, not reduce it. So the statement that best fits is that HDV requires concomitant HBV infection.

HDV is a defective virus that cannot form its own outer shell and must borrow the hepatitis B surface antigen (HBsAg) to assemble infectious particles. Because of this, HDV infection can occur only in the setting of active HBV infection—either at the same time as HBV enters (coinfection) or later in someone who already carries HBV (superinfection). Vaccination against HBV prevents HBV infection and, by eliminating HBsAg, removes the necessary component for HDV to assemble, thereby reducing HDV risk. Conversely, HDV infection tends to accelerate liver disease and increases the risk of progressing to cirrhosis and hepatocellular carcinoma, not reduce it. So the statement that best fits is that HDV requires concomitant HBV infection.