A deadly fungus which is a major cause of infection on hospital wards is becoming resistant to drugs, according to doctors.

Candida albicans is normally associated with mild infections of the genitals or mouth but can be fatal when caught by someone who has a serious illness or is recovering from surgery.

One in four blood infections picked up in hospitals come from it and around half of these patients die.

When a patient has a weakened immune system, the bacteria can move from the gut to the bloodstream and multiply on plastic surfaces within the body like pacemakers and catheters, attacking organs.

Dr Carol Munro, from Aberdeen University, told a conference of the Society for General Microbiology that if the drugs used to treat the infection did not kill the fungus immediately, there was a risk it could adapt its cells and spread.

Hospital wards

At the moment, the way drugs tackle C. albicans is to prevent sugars being produced that help the infection to grow.

More research is now taking place to develop stronger medicines to combat it.

Scientists used powerful X-rays at a facility in Oxfordshire to probe its structure. They were able to spot how it used proteins to attach itself to human tissues.

Dr Paula Salgado, from Imperial College London, who took part in the research, said: ‘Most healthy women will have thrush or other mild yeast infection at some point in their lives, but what is less well known is that yeasts can be lethal ”superbugs”, and a major health concern for vulnerable hospital patients.

‘What I find most concerning is the fact that we don’t seem to have an effective way to control the most severe cases of these infections, which can kill half of those affected.

‘Our work allows us to understand the details involved and provide vital clues to develop new drugs and clinical applications.’

The findings are published in the journal Proceedings of the National Academy of Sciences.