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Delta agent (Hepatitis D) - Overview
Hepatitis D virus
Definition of Delta agent (Hepatitis D):
Delta agent is a type of virus called hepatitis D that causes symptoms only in people who also have a hepatitis B infection.
Causes, incidence, and risk factors:
Hepatitis D virus (HDV) is only found in people who carry the hepatitis B virus. HDV may make a recent (acute) hepatitis B infection or an existing long-term (chronic) hepatitis B liver disease worse. It can even cause symptoms in people who carry hepatitis B virus but who never had symptoms.
Hepatitis D infects about 15 million people worldwide. It occurs in 5% of people who carry hepatitis B.
Risk factors include:
- Abusing intravenous (IV) or injection drugs
- Being infected while pregnant (the mother can pass the virus to the baby)
- Carrying the hepatitis B virus
- Men having sexual intercourse with other men
- Receiving many blood transfusions
- Reviewed last on: 11/23/2010
- David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Perrillo R. Hepatitis B and D. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier;2010:chap 78.