New Zealand researchers have made a discovery which could potentially save the lives of many of the four hundred million people living with hepatitis B worldwide.
They've identified a key DNA marker in the blood to help determine which patients with chronic hepatitis B are likely to go on to get liver cancer or die from other liver-related conditions.
The Health Research Council-funded study, led by Auckland City Hospital hepatologist Professor Ed Gane, followed up with 570 patients from Kawerau in the Bay of Plenty who were diagnosed with chronic hepatitis B in 1984.
These patients were part of the Hepatitis Foundation of New Zealand's pioneering Kawerau Community Study, led by Mr Alexander (Sandy) Milne, MBE.
Milne, a lab technician, was alarmed at the epidemic levels of the virus he was seeing in localised areas of the country and the high rates of liver cirrhosis and cancer the virus was causing.
He went on to establish the Hepatitis Foundation which first tested 97 per cent of Kawerau's 9000 residents for the virus. Half of them tested positive. New Zealand was found to have one of the highest rates of Hepatitis B in the developed world. Milne’s work later saw New Zealand become the first sovereign nation in the world to offer free vaccinations to babies to prevent the virus.
Professor Gane and his co-investigators analysed blood serum collected from the Kawerau study cohort. The serum was perfectly preserved having been stored in freezers and meticulously maintained at minus 20 degrees centigrade for nearly 30 years. The research team then followed up with all survivors of the Kawerau study between October 2011 and November 2013, collecting blood samples and checking for signs of liver disease.
That research has now identified exactly which of those study patients will go on to develop liver cancer and cirrhosis by examining levels of hepatitis B virus in their blood samples.
"Levels of the hepatitis B virus in the blood greater than 100,000 viruses per millilitre of blood, is a predictor for developing problems long-term" Professor Gane says.
"It also found that people who were older when they were first followed and Maori were also more at risk of developing complications," he says.
As a result of the research team's findings, every patient on New Zealand's current national community-based surveillance programme will soon have their baseline hepatitis B virus DNA levels recorded. Those patients with high virus DNA levels will receive increased surveillance for liver cancer.
Kawerau father Klyjah Peters is one of those patients. He was first diagnosed with the virus as a six year old in 1984. Study nurse Helen Purcell has monitored his health regularly since with bi-annual blood tests. Peters was recently found to have early stage cirrhosis of the liver which is being successfully treated with drugs to prevent its spread.
"Hopefully I'm around much longer for my kids and grandkids" says Peters.
"If we're able to say at an early stage that a particular person's at risk for liver cancer then we can put them into more intensive follow-up so we can pick up the liver cancer at a very early stage," says Professor Gane.
About 2 billion people worldwide have been infected with the hepatitis B virus and about 400 million people have chronic hepatitis B, of whom almost 40 per cent will die from complications.
"Nearly a million people a year die from liver cancer from hepatitis B, mainly in the Asia and Pacific region. Only one carcinogen kills more people than hepatitis B and that’s tobacco, so it’s a huge health burden," says Professor Gane.
Currently about 100,000 people in New Zealand are chronically infected with the hepatitis B virus.