Hospital superbug C. difficle source is unclear, say scientists

Scientists cannot explain how 75 per cent of people catch the superbug C. difficile, after a study showed that only a quarter of infections in one hospital system were traced to contact with a suffering patient.

C. difficile is a spore-forming bacterial species associated with severe, sometimes fatal, diarrhoea. It is unclear how many healthy, asymptomatic adults carry C. diff in their colons, but in times of ill health, and especially after broad-spectrum antibiotic treatment, it can overgrow and cause disease.

Scientists previously believed that C. difficile spreads through personal contact with infected patients showing symptoms.

However, new findings from a team at John Radcliffe Hospital in Oxford show that only 25 per cent of infections actually spread this way.

Scientists collected stool samples from almost 15,000 patients in one hospital system. They found evidence of C. difficile in 4.4 per cent of patients, and further tests identified 69 strains of the bacterium. However, only 23 per cent of these could be linked to known symptomatic patients.

These results show that hospitals may be adopting the wrong strategy for combating the superbug on the wards. Preventative steps like hand washing and isolation of infected patients may only address a quarter of the infections.

Other ways C. diff might be able to spread included transmission by non-symptomatic carriers, like patients' relatives and staff, or through food or animals.

The authors wrote in the online journal Public Library of Science Medicine: 'In this endemic setting with well-implemented infection control measures, up to three quarters of new (C. diff) infections are not easily explained by conventional assumptions of ward-based transmission from symptomatic patients and so may not be targeted by current interventions.

'A better understanding of other routes of transmission and reservoirs is needed to determine what other types of control interventions are required to reduce the spread of C. difficile.'

Whilst superbugs like C. difficile can be found in any hospital environment, private hospitals have a much lower rate of infection than NHS hospitals. With private medical insurance you will stay in a private room with an ensuite bathroom, putting you at much lower risk of contracting C. difficile.