296 million people live with hepatitis B, and of this number, between 15 and 20 million suffer from hepatitis delta. This coinfection leads to a considerably more serious liver disease than hepatitis B alone. Faster progression to liver fibrosis, increased chance of liver cancer, early decompensated cirrhosis and liver failure can all occur from this coinfection.
Hepatitis Delta
Hepatitis delta, also known as Hepatitis D or HDV, is a liver infection caused by the Hepatitis delta virus that results in the most severe form of viral Hepatitis. Only those already infected with Hepatitis B can acquire Hepatitis delta – this strain is entirely reliant on the presence of the Hepatitis B virus to reproduce.
Types of Infection
Hepatitis delta can be acquired via either:
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Coinfection (infection with Hepatitis B and delta at the same time)
A coinfection generally resolves spontaneously after about 6 months, but it can sometimes result in life-threatening or fatal liver failure.
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Superinfection (infection with Hepatitis D after a person has already acquired Hepatitis B)
A superinfection is the most common form of Hepatitis delta and leads to a more severe liver disease than a chronic Hepatitis B infection alone.
Prevention
- There is no vaccine for Hepatitis delta itself, but through vaccination and prevention of the required Hepatitis B strain, further infection can be prevented.
- Like Hepatitis B, testing for the delta strain is via a simple blood test.
- It is important that people living with chronic Hepatitis B get tested for hepatitis delta, due to the risk of superinfection.
- As with any strain of Hepatitis, getting tested early can ensure the appropriate care is provided and steps are taken to mitigate the effects of the virus.
About the virus
- The Hepatitis delta virus is a single-stranded, circular RNA virus and is the smallest virus known to infect humans.
- It is unusual in that it needs specific help from the Hepatitis B virus in order to infect and replicate in liver cells.
- The virus’s defective structure requires the envelope proteins of the Hepatitis B virus for its own assembly; thus, new Hepatitis delta virus particles can only be produced in a liver cell that is already infected with the Hepatitis B virus.