MRSA bacteria can be deadly
MRSA is mainly spread by patients moving between hospitals, Dutch researchers have said.
The authors have called for more screening of people who are repeatedly admitted to different hospitals to try to break this transmission cycle.
They said this would eventually help to eradicate MRSA.
The conclusions were drawn from a large study of the geographical location of different strains of MRSA across 26 European countries.
MRSA is a potentially lethal bug which is difficult to combat because it has developed resistance to some antibiotics.
The study was published in the journal, PloS Medicine.
The aim was to find out more about the distribution of the different strains so as to shed light on how the infection spreads.
Hajo Grundmann from the University Medical Centre in Groningen in the Netherlands, who was the lead author of the report, said: "To my utter surprise, we found that MRSA strains were geographically concentrated."
He concluded that the distribution of MRSA suggested it is transmitted by patients who frequent different hospitals, rather than being spread in the community.
"MRSA appears to be spread by patients who ping-pong around between hospitals. These are often frail or elderly people with on-going health problems."
"The exciting thing is that if we know that MRSA is spread by this core group who are going back and forth between hospitals, we can do something about it and we may ultimately be able to eradicate MRSA."
"The message of this report is that doctors should try to identify people who often move between hospitals or other health care institutions such as nursing homes and they should be screened for MRSA.
"This could be done in hospital or at GP surgeries.
"Then steps can be taken to treat those who have the infection and limit transmission of MRSA."
The Health Protection Agency said it was already well known that MRSA infections usually occured in hospitals, and that nursing and residential homes have had problems with MRSA colonisation.
A spokesperson for the HPA said a substantial screening programme was already in place and was due to be extended.
They said: "The Department of Health has established a policy that across the NHS all relevant elective admissions should be tested for the presence of MRSA, extending to all admissions - including emergencies - by 2010/11.
"This enables treatment, for example, special washes or ointments to be given to reduce or clear MRSA in patients before surgery."
'Tour de force'
The large-scale study analysed samples from 450 hospitals across Europe.
Doctors will be able to use an interactive map from the study, which is also available to the public, which gives information on MRSA strains in different locations.
"This research is a tour de force," said Professor Richard James, director of the Centre for Healthcare Associated Infections at the University of Nottingham.
But he added that the study found few community-acquired strains of MRSA because it concentrated on invasive infections.
"Community-acquired MRSA strains cause infections in younger people in the community who have had little contact with healthcare systems.
These are unfortunately much less likely to be controlled by interventions that reduce transmission of hospital-acquired MRSA strains."