Delta agent is a type of virus called hepatitis D. It causes symptoms only in people who also have hepatitis B infection.
Hepatitis D virus (HDV) is found only in people who carry the hepatitis B virus. HDV may make liver disease worse in people who have either recent (acute) or long-term (chronic) hepatitis B. 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 a small number 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
Hepatitis D may make the symptoms of hepatitis B worse.
Symptoms may include:
- Abdominal pain
- Dark-colored urine
- Joint pain
- Loss of appetite
Many of the medicines used to treat hepatitis B are not helpful for treating hepatitis D.
You may receive a medicine called alpha interferon for up to 12 months if you have a long-term HDV infection. A liver transplant for end-stage chronic hepatitis B may be effective.
People with an acute HDV infection most often get better over 2 to 3 weeks. Liver enzyme levels return to normal within 16 weeks.
About 1 in 10 of those who are infected may develop long-term (chronic) liver inflammation (hepatitis).
Complications may include:
- Chronic active hepatitis
- Fulminant hepatitis
When to Contact a Medical Professional
Call your health care provider if you have symptoms of hepatitis B.
Steps to prevent the condition include:
- Detect and treat hepatitis B infection as soon as possible to help prevent hepatitis D.
- Avoid intravenous drug (IV) abuse. If you use IV drugs, avoid sharing needles.
- Get vaccinated against hepatitis B.
Adults who are at high risk for hepatitis B infection and all children should get this vaccine. If you do not get Hepatitis B, you cannot get Hepatitis D.
Hepatitis D virus
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: Elsevier Saunders; 2010:chap 78.
Review Date 11/20/2014
Updated by: Jenifer K. Lehrer, MD, Department of Gastroenterology, Frankford-Torresdale Hospital, Aria Health System, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.