05 Jul 2018
How prevalent is hepatitis D virus infection in Australia?
Hepatitis D virus (HDV) is considered to cause the most severe disease of all the hepatitis viruses yet until recently, not much was known about the prevalence in Australia.
Researchers at the Peter Doherty Institute for Infection and Immunity (Doherty Institute) have investigated the prevalence and trends of the virus and published their findings in the Internal Medicine Journal.
Kathy Jackson, Victorian Infectious Diseases Reference Laboratory (VIDRL) Senior Medical Scientist, lead author on the paper explains the findings.
HDV is estimated to infect around 10-20 million people worldwide or around five to 10 per cent of hepatitis B virus (HBV) carriers.
Although it is the smallest of the viruses known to infect humans, it is also considered the most pathogenic of the hepatitis viruses, and yet is often overlooked.
In Australia there are around 20 to 30 cases of HDV diagnosed each year, 30 years ago, the major risk factor was injecting drug use (IDU).
However recent epidemiological data suggests the majority (64 per cent) of cases in Victoria are individuals born in endemic areas such as Sudan, Pakistan, Vietnam, Afghanistan, Romania and Sierra Leone. There is also evidence of the Pacific Island strain of HDV genotype 1 in Queensland.
IDU still plays a role in transmission within Australia. Our study analysed the strains of HDV circulating in Australia and revealed a strain that has been isolated from people in correctional facilities.
HDV cannot survive without HBV - it can occur as either a co-infection (simultaneous exposure) with HBV or superinfection (exposure after established HBV).
HBV/HDV co-infection has been associated with more rapid progression and severe liver disease, cancer and death than HBV mono-infection. Acute HDV can also cause fulminant hepatitis which is a rare form of severe liver necrosis and atrophy often requiring liver transplantation.
Transmission of HDV in endemic areas can occur within families through contact with infected blood and/or body fluids although; unsafe medical practices, sexual transmission and IDU are also risk factors for acquisition, particularly in non-endemic countries.
Interferon therapy is currently the only option for treatment of HDV infection. However there are several new investigational therapeutics on the horizon targeting both HBV and/or HDV.
HDV infection is a notifiable disease, with tests to detect the virus performed at the Serology and Molecular Microbiology Laboratories of the Victorian Infectious Diseases Reference Laboratory (VIDRL) at the Doherty Institute.
VIDRL recommend that all newly diagnosed hepatitis B patients and those with worsening liver disease be screened for HDV.
CLICK HERE to access the published article.