Diarrhoea-causing superbug C. difficile has 'evolved' to target hospitals

Monday 12th August 2019 16:15 BST

Clostridium difficile (C. difficile) is mutating into two separate species, one of which is better able to spread on hospital wards, they added.

The bug is also said to have a sweet tooth that thrives on a sugar-rich Western diet.

Researchers discovered that C. difficile was mutating into two species while carrying out the largest ever genomic study of it.

Whole genomes from 33 countries were analysed, and strains of the bug were isolated from dogs, pigs, horses and the environment.

The emerging species comprised about 70% of samples from hospital patients, researchers found.

Genes that metabolise simple sugars had mutated, while the genes that form the spores from which people become infected had also changed, making them more resistant to common hospital disinfectants.

"Our large-scale genetic analysis allowed us to discover that C. difficile is currently forming a new species with one group specialised to spread in hospital environments," said joint first author Dr Nitin Kumar from the Wellcome Sanger Institute.

"This emerging species has existed for thousands of years, but this is the first time anyone has studied C. difficile genomes in this way to identify it."

Professor Brendan Wren, from the London School of Hygiene & Tropical Medicine, said: "Ultimately, this could help understand how other dangerous pathogens evolve by adapting to changes in human lifestyles and healthcare regimes which could then inform healthcare policies."

C. difficile forms resistant spores that remain on surfaces and spread easily between people.

While a healthy person with millions of good bacteria may not be susceptible, antibiotics can wipe out normal gut bacteria, leaving a patient vulnerable to infection.

As well as severe diarrhoea, C. difficile can cause bowel inflammation and be difficult to treat.

It is thought to be the leading cause of antibiotic-associated diarrhoea worldwide.

The study is published in the Nature Genetics journal.

Now On Air
Libby on a Sunday
Join Libby on Sunday mornings for great music from local artists, good news and anything else worth chatting about