13 Nov 2020
Hepatitis B: Fresh insights into an ancient condition
This week is NAIDOC Week - a celebration across Australia celebrating the history, culture and achievements of Aboriginal and Torres Strait Islander peoples.
The Doherty Institute would like to recognise the celebration by highlighting some of the important work we are doing in Indigenous health.
New research has revealed that the prevalence of chronic hepatitis B in Indigenous Australians has previously been underestimated, with Indigenous Australians in the Northern Territory nearly five times more likely to be living with the disease than the general population. The study, published in Internal Medicine Journal, investigated the prevalence of chronic hepatitis B over a 20-year period following the implementation of universal vaccination in the Northern Territory.
Hepatitis B is a potentially life-threatening liver infection caused by the hepatitis B virus (HBV) infection, which can result in chronic liver infection, cirrhosis (scarring of the liver) or liver cancer. While it carries a range of health complications, chronic hepatitis B virus is preventable through vaccination.
The a research team was led by the Doherty Institute – a joint venture partnership between The Royal Melbourne Hospital and the University of Melbourne – and Menzies School of Health Research, who combined hospital and pathology data spanning a 20-year period to create the first longitudinal study investigating HBV in the Northern Territory.
Lead author Ashleigh Qama, Epidemiologist with the WHO Collaborating Centre for Viral Hepatitis at the Doherty Institute and Deakin University final year medical student, said that the data revealed the extent to which Aboriginal and Torres Strait Islander people are disproportionately affected by HBV than non-Indigenous populations.
“Hepatitis B is one of the world’s oldest viruses,” Ms Qama said.
“Past research has found that the precursors to early humans and Aboriginal people’s ancestors were likely to have had hepatitis B, so it’s co-existed alongside Aboriginal Australians for a long time.
“Our study revealed that Aboriginal Australians in the Northern Territory carry a much greater burden of disease than previously thought, with more than five per cent of individuals living with chronic hepatitis B at the end of the study period.”
The research shed light on vaccine efficacy, addressing concerns that the Northern Territory’s high temperatures had impacted the effectiveness of HBV vaccine delivery in the early years of standardised vaccination, as the vaccine requires effective cold chain transport and storage.
“The data revealed that this was not the case and that the vaccine has been offering sufficient protection against chronic hepatitis B infection,” continued Ms Qama.
“What it did show us, however, is that the vaccine is not as effective against acute hepatitis B infections for a small number Aboriginal Australians as it is for non-Indigenous Australians.
“This distinction is important. While the hepatitis B vaccine is not perfect, we can see that it has significantly helped to reduce the prevalence of the virus in the Northern Territory and gives us hope that we can decrease the burden of disease for future generations.”
Members of the research team are currently working towards the elimination of chronic hepatitis B from Indigenous Australians through Hep B PAST, a research project led by Dr Jane Davies at the Menzies School of Health Research in the Northern Territory. It offers communities access to culturally appropriate effective education tools in their first language and improve the diagnosis of chronic hepatitis B, improving community health literacy and the cascade of care for individuals living with CHB in the region.
“This study shows that universal vaccination in the Northern Territory has decreased the prevalence of HBV, and that ongoing vaccination of infants is a crucial element of controlling chronic hepatitis B in Indigenous communities,” Ms Qama said.