Clostridium difficile (C. difficile) is the most commonly diagnosed cause of infectious hospital-acquired diarrhoea in developed countries, including Australia.
Canada, Europe, and the US have all recently seen sudden increases in rates of C. difficile infection and high mortality rates, with people over 65 years of age being most at risk, suggesting the emergence of a highly virulent strain of C. difficile.
Professor Thomas Riley, Professor in Microbiology and Immunology at the University of Western Australia, outlines the characteristics of the various strains of C. difficile.
"Acquisition of C. difficile is facilitated by its ability to form spores that are resistant to many disinfectants, so that it remains viable in the hospital environment for long periods of time," says Prof Riley.
He adds that C. difficile strains have also shown resistance to one group of antibiotics (fluoroquinolones), possibly through overuse of these medications.
The virulent strain cannot be differentiated from other strains without molecular typing, which makes it difficult to know whether the organism has reached Australia's shores.
He says many laboratories in Australia, to save money and time, are using a testing technology that may not detect the virulent C. difficile strain.
Prof Riley recommends targeted surveillance, with one or two laboratories being funded periodically to test samples from a number of different hospitals.
"The value of sensible policies regarding antibiotic use, and good infection control staff and procedures, cannot be over emphasised," he says.
"In the long term, such initiatives are likely to have an impact not only on C. difficile-associated diarrhoea but also on other infection control problem organisms."