Big hospitals infect smaller ones with superbugs

By NATALIE WALKER
Published on 15/05/2012 00:39

HOSPITALS in large cities act as breeding grounds for the superbug MRSA prior to it spreading to smaller hospitals, a study has found.

Researchers have found evidence that shows for the first time how the potentially fatal superbug spreads between different hospitals across the country.

The University of Edinburgh study looked at the genetic make-up of more than 80 variations of a major clone of MRSA found in hospitals in the UK.

Scientists were able to determine the entire genetic code of MRSA bacteria from samples taken from a number of infected patients.

They then identified mutations in the bug which led to the emergence of new types of MRSA and traced how they were spread between patients around the country.

Study leader Dr Ross Fitzgerald, of the university’s Roslin Institute, said: “We found that variants of MRSA circulating in regional hospitals probably originated in large city hospitals.

“The high levels of patient traffic in large hospitals means they act as a hub for transmission between patients, who may then be transferred or treated in regional hospitals.”

MRSA – methicillin-resistant staphylococcus aureus – first appeared in hospitals around 50 years ago after the introduction of antibiotics.

In recent years the superbug has become increasingly resistant to the drugs developed to treat it.

Paul McAdam, also of the Roslin Institute, said: “Our findings suggest the referral of patients to different hospitals is a major cause of MRSA transmission around the country.

“This knowledge could help in finding ways to prevent the spread of infections.”

The paper, published in the journal PNAS, also revealed the MRSA strain which the researchers looked at had evolved from antibiotic-sensitive bacteria which existed more than 100 years ago.