INTERCONTINENTAL SPREAD OF A MULTIDRUG-RESISTANT METHICILLIN-RESISTANT STAPHYLOCOCCUS-AUREUS CLONE

Two hundred ten methicillin-resistant Staphylococcus am eus (MRSA) iso lates recovered between 1990 and 1997 from three Portuguese hospitals located in Lisbon and Oporto were analyzed by molecular fingerprinting techniques. The hybridization of ClaI restriction digests with the me cA- and Tn554-specific DNA probes combined with pulsed-field gel elect rophoresis documented the abrupt appearance and extensive intrahospita l spread of the Brazilian epidemic MRSA clone in the 1995 samples of e ach one of the three hospitals analyzed-suggesting the intercontinenta l transfer of this strain from Brazil to Portugal. The appearance of t his clone may challenge the dominance of another highly epidemic impor ted clone-the Iberian MRSA, currently the mast widely spread MRSA clon e in Portuguese hospitals.