Many Australians probably think tuberculosis (TB) is a disease of the past. They are wrong.TB is sitting on Australia’s doorstep, with the fastest growing incidence found in South East Asia.
Professor Warwick Britton, who leads Australia’s largest TB research program at the Centenary Institute in Sydney, says this ancient disease is clever enough to mutate and outsmart our immune system.
"Tuberculosis is cunning," he says. "It can be traced back to the mummies of Ancient Egypt and has continued to adapt to everything we have thrown at it. Not only does it mutate to resist treatment, but it also evades the immune system by hiding in the cells that are meant to
One worrying aspect of TB is the ease with which it can spread – through the air when those infected cough, sneeze or talk.
"Disturbingly, multi-drug resistant tuberculosis has evolved in recent years – and now we even have extensively multi-drug resistant tuberculosis. That is TB resistant to all known treatments," says Professor Britton.
"Despite this, I truly believe we can win the fight with a sustained and multi-faceted approach, like the one we are undertaking at Centenary."
On World TB Day (March 24), Professor Britton stresses the fight is worth winning. One third of the world’s population, or two billion people, are infected with TB. Every second of every day another person is infected. More than 1.6 million people die each year.
One step to defeating TB in countries where it is widespread, such as Vietnam, Indonesia and the Philippines, is developing and implementing new strategies for disease control.
"In partnership with the National Tuberculosis Control Program (NTCP) in Vietnam and the Woolcock Medical Research Institute, we are looking for practical ways of improving TB control in this highly endemic country," Professor Britton explains. "We are sending a young
clinical scientist to work on the ground with the NTCP in Hanoi and we shall develop new strategies that can be applied to other countries where TB is an issue."
But we need to develop new tools to improve disease control. Therefore, research is vital to stopping TB in its tracks.
Back in Sydney, Centenary Institute scientists are attacking TB from different angles:
- investigating ways to improve the current vaccine;
- finding new vaccines and new targets for TB drugs; and
- identifying the genes that make some people more susceptible to the disease.
Professor Britton explains: "The current BCG vaccine has been around since the 1920s but it has limitations. We desperately need a vaccine that is stronger and lasts longer. We are looking at modified forms of BCG and its impact on immunity with promising results.
"Additionally, we recently discovered an enzyme crucial to the spread of TB within the body. This may become a target for new TB drugs."
Centenary scientists are also exploring how variations in genes change the immune response to TB and the impact this has on disease progression. This major international collaboration will shed light on the genetic reasons for why some infected people develop TB quickly, and others, years later.
Centenary Institute Executive Director, Professor Mathew Vadas, says expansion of the TB research facility at Centenary Institute is critical to Professor Britton’s fight against TB.
"We have commenced work on the expansion of the PC3 laboratory – a special containment facility that allows the team to conduct their research with live TB," he says. "This investment will help accelerate the pace of Professor Britton’s research – reducing the burden of TB both
in our region and around the world."
(Source: Centenary Institute: March 2009.)