A team of scientists, led by Monash University researcher Dena Lyras,has unlocked the secrets of a disease causing bacterium that kills hospital patients worldwide.
Scientists have known for years that the ‘superbug’ Clostridium difficile causes severe diarrhoea in hospital patients taking antiobiotics, according to Lyras. However they could not figure out exactly how it caused illness.
“When people go into hospital and are treated with antibiotics, these antibiotics do not only kill the bad bugs but the good bugs as well,” explains Lyras. “When this happens this bug is able to grow in the gut and make toxins that can kill people who are already really sick. We knew that this bacteria produces two toxins, toxin A and B, and our work aimed to identify which toxin was responsible for causing illness.”
The bug is found in every hospital in Australia and was estimated in 1992 to cost each hospital $1.25 million per year.
It is also believed to have contributed to 8000 deaths in Britain in 2007.
Using a host of scientific procedures including DNA manipulation, Lyras and her collegues created mutants of the superbug and went on to identify that it was toxin B produced by the bacterium that caused disease.
“The work we did was able to stop bacteria from making either one of the toxins- when we took toxin A away, the bug caused illness but when we took toxin B away, it didn’t, so we realised that it was toxin B that was responsible for the illness.”
The discovery was recently published in the prestigious scientific journal, Nature.
Lyras reveals that her new focus now is on developing a treatment for the illness.
“There are currently antibiotics that can be used to treat this bug. The problem with this bug as with many bugs is that they develop resistance to antibiotics, and so they’re very difficult to treat once they’ve developed resistance. We are investigating a number of different ways to combat the bug and are very confident that we will find a prevention and treatment in the next five to ten years.”