New strains of MRSA have been identified in the Republic that have not been found anywhere else in the world.
The strains were identified during a retrospective study of MRSA isolates recovered in Irish hospitals between 1971 and 2002.
Prof David Coleman, head of the biosciences division of the school of dental science at Trinity College Dublin, said yesterday the research found there had been several different strains of MRSA present among Irish patients over the past three decades.
"The main finding was that we've had waves of invaders over the last three decades.
"There has not been a single MRSA strain, there have been many and the population is continuing to change so we are actually importing MRSA from abroad and we are exporting it, and there are new ones developing here that nobody else has seen."
He suspects the reason certain MRSA strains were found in the Republic and not elsewhere was "people had not done such detailed analysis" elsewhere. This was the most comprehensive study on MRSA isolates ever to be undertaken in Ireland.
Prof Coleman was speaking after the official opening by Minister for Health Mary Harney of new laboratory and research facilities at the Dublin Dental School, where work on MRSA has been ongoing since 1982. It was a problem then too butjust didn't receive the same attention, he said. However he suspects the incidence of infections is increasing.
MRSA (methicillin-resistant Staphylococcus aureus) is an antibiotic resistant bug that can prove fatal if it gets into patients' bloodstreams. There were 315 reported cases of bloodstream infection reported by hospitals in the first six months of this year.
The laboratory at the dental school provides "the tools to track infection from one hospital to another", Prof Coleman said.
"If you can identify what type of organism is present you can very easily find the source of infection very, very quickly.
"In one case we tracked an infection that occurred in a large acute hospital to a different continent very, very quickly, and were able to identify that an outbreak here in Dublin had originated on a different continent. An Irish person brought it back. . . from the Middle East."
"It's a case of knowing your enemy. If you know what you are dealing with it's easier to control it.
"Being able to rapidly identify the organism and track it is very important from the point of view of antibiotic resistance and resistance to disinfectants. You must know what you are dealing with."
Prof Coleman said MRSA, a problem for hospitalised patients, had recently become a problem in the community, and was being researched by the new laboratory and research centre in collaboration with the national MRSA reference centre in St James's Hospital.
The centre has also recently developed a dental chair which automatically disinfects its water lines. MRSA, however, is not a problem for dental patients, Prof Coleman added.