Big city hospitals 'breed and spread MRSA across the country'
Genetic evidence suggests MRSA is transferred via patients from city hospitals to smaller regional hospitals
08:45 GMT, 15 May 2012
Hospitals in large cities act as breeding grounds for the superbug MRSA before it spreads out across the country, a study has revealed.
Researchers have found evidence that variants of the potentially deadly infection found in smaller regional hospitals probably came from larger city hospitals.
The University of Edinburgh study looked at the genetic make-up of around 80 variants of a major clone of MRSA found in hospitals.
This electron micrograph of a deadly cluster of MRSA bacteria. Superbug infections peaked in 2003
Scientists were able to determine the genetic code of MRSA bacteria taken from infected patients. They then identified mutations in the bug, which led to the emergence of new MRSA variants and traced their spread around the UK.
Dr Ross Fitzgerald, of the Roslin Institute at the university and who led the study, said: '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.'
The institute's Paul McAdam, an author of the research paper, said: 'Our findings suggest that 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.'
MRSA (methicillin-resistant staphylococcus aureus) started to appear around 50 years ago following the introduction of antibiotics, to which the bacteria has become increasingly resistant.
Transfer: MRSA infections travel between major city hospitals and smaller regional centres
Infections are more common in hospitals as patients often have an entry point for the bacteria to get into their body such as a wound or drip. They also tend to have weaker immune systems.
Earlier this month a report in the British Medical Journal revealed that cases of MRSA have plummeted since the launch of a hand-washing campaign in 2004.
Rates for the superbugs MRSA rose
significantly in the 1990s from just 100 a year to a peak of 7,700 in
2003 to 2004. Following the launch of the hand-washing campaign rates
fell steadily each year to 1,481 cases in 2010 to 2011.
The report said the simple instructions to encourage doctors and nurses to use soap
and water or alcohol gel between patients had saved more lives than any
medical development for a generation.