Hepatitis D (delta)
Content date: 10 November 2026
Hepatitis D requires hepatitis B infection. Testing matters even without symptoms because finding D can change treatment and follow-up.
Your next step
If you have hepatitis B, ask whether D testing was completed and whether RNA testing is needed.
Get urgent help: Vomiting blood, black stools, new confusion or drowsiness, or severe jaundice with significant illness need urgent care.
How does it differ from hepatitis B?
- B and D may be acquired together, or D may infect someone who already has B. D can accelerate liver injury and scarring, but its presence does not mean liver failure has occurred. Tests and liver function guide assessment, not tiredness alone.
Testing
- People who are HBsAg positive should have hepatitis D antibody testing at least once. A positive antibody result needs HDV RNA testing to establish active infection.
- Repeat testing may be appropriate according to exposure or liver results. Low HBV DNA does not exclude D, and a pending result is not negative.
Treatment and follow-up
- A liver specialist assesses scarring, liver function and both viruses. HDV treatment such as bulevirtide, with or without interferon in selected cases, may be suitable depending on safety, approval and local availability.
- Hepatitis B medicines may remain necessary but do not directly treat D. Do not stop treatment yourself. Adults with chronic D need regular follow-up, usually including liver imaging every six months for cancer surveillance; your team chooses the method.
Protecting family
- Transmission occurs through blood and certain body fluids, not hugging or ordinary food sharing. Do not share needles, razors or toothbrushes. Discuss sexual precautions and family testing.
- Hepatitis B vaccination protects uninfected people against B and associated D. It does not prevent D infection in someone who already has B, so blood precautions remain important. There is no separate D vaccine.
A practical next step
- Bring complete B and D results and a medicine list. Discuss hepatitis A vaccination if not immune. Avoid alcohol and unknown supplements, and arrange result review and follow-up.
When to get help
Vomiting blood, black stools, new confusion or drowsiness, or severe jaundice with significant illness need urgent care.
New jaundice, abdominal or leg swelling, or difficulty obtaining medicine need early contact.