Characterisation of methicillin-resistant Staphylococcus aureus isolates from dogs and their owners.

Ten methicillin-resistant Staphylococcus aureus (MRSA) isolates from healthy owners and their pets were characterised by susceptibility testing, staphylococcal chromosome cassette (SCC)mec and agr typing, and detection of the Panton-Valentine leukocidin (PVL) genes. Two human and three dog isolates harbouring SCCmec type III appeared to be of hospital origin. The five remaining isolates carried SCCmec type IV, with three being multidrug-resistant. One type IV isolate was PVL-positive and a prototypic agr type 3, typified by strain MW2. This is the first report of this type in association with nasal carriage. Drug resistance may be increasing among community isolates of MRSA.