New evidence to help fight the yeast superbug that experts say is a real threat to our global health.

UK scientists are reporting for the first time that a deadly form of a drug resistant yeast that has caused hospital outbreaks and deaths across the world is sensitive to the disinfectant most widely used to sterilise surgical instruments.

In a new study published the team discovered in laboratory experiments that a recently-discovered human fungal pathogen, Candida auris readily forms impermeable layers called biofilms that are resistant to most drugs used to treat fungal infections.

Significantly the researchers were also able to show that these Candida auris biofilms are sensitive to the disinfectant chlorhexidine, which is standard use in hospitals to sterilise instruments and wipe the patients’ skin before surgery. It could mean a breakthrough for doctors trying to control the spread of infection in hospitals.

Dr Leighann Sherry.

Working with experts in Glasgow, Manchester and Bristol, medical mycologist Dr Leighann Sherry compared Candida auris with other Candida species commonly causing infections in humans. She found it had an ability to form biofilms – impermeable layers of microorganisms that can grow on many different surfaces. Leighann, a fungal researcher at University of Glasgow, explains: “These features not only contribute to its virulence, but also to its survival in hospital environments, increasing its ability to cause outbreaks.”

Candida auris was first reported in 2009 from the ear canal of a woman in Japan. More recently, it has been associated with life threatening invasive diseases such as pericarditis (swelling around the heart) and bloodstream and wound infections.

It has caused hospital outbreaks in America, India, Kuwait, Pakistan, Venezuela and Colombia, and in a UK intensive care unit, where 20 per cent of patients, found to be carry Candida auris, developed a bloodstream infection, which often results in long hospital stays, high medical costs, and poor outcomes.

* Emerging Infectious Diseases

Researchers found the ability of this organism to form biofilms made it resistant to most drugs used for the treatment of severe fungal infections. They also discovered that normal concentrations of the skin disinfectant chlorhexidine were active against Candida auris biofilms.

Dr Riina Richardson.

Dr Riina Richardson, Consultant in Medical Mycology at the University Hospital of South Manchester and Senior Lecturer in Infectious Diseases at The University of Manchester, was instrumental in determining the study and believes the results are clinically significant and merit further exploration. She says: “Although the exact mode of transmission in the hospital setting is unknown, it appears that Candida auris may substantially contaminate the rooms of colonised or infected patients. These factors, together with its resistance to most antifungal agents, may well explain why it is an emerging pathogen.

Importantly, these results suggest that it is unlikely that its spread and prevalence could be controlled with antifungal stewardship approaches alone but that infection prevention measures are critical. Chlorhexidine appears to be effective in disinfecting contaminated hospital environments”, she adds.

Due to the interest in this emerging fungal pathogen, Dr Sherry has been awarded an ESCMID Research Grant 2017 to investigate this organism in greater detail.

For more information please contact Susan Osborne, Director of Communications, The Goodwork Organisation, on 07836 229208.