Overview

Infection with the hepatitis D virus (HDV), or delta agent, occurs only in people who are already infected with the hepatitis B virus (HBV). HDV infection may make HBV infection more severe.

In people who have long-term (chronic) HBV infection, HDV infection can make liver disease worse. Or it can cause a person who did not have symptoms before to develop liver problems more rapidly.

Vaccination against hepatitis B will also prevent hepatitis D virus infection.

Hepatitis D virus infection is rare in the United States.