Molecular typing of methicillin-resistant staphylococci isolated from cats and dogs

Objectives: Methicillin-resistant staphylococci (MRS) isolates from healthy and diseased cats and dogs were characterized by staphylococcal cassette chromosome mec (SCCmec), multilocus sequence typing (MLST) and cassette chromosome recombinase gene (ccrAB) sequencing. Methods: PCR-directed SCCmec typing was carried out for all MRS isolates and two Staphylococcus aureus and two Staphylococcus epidermidis strains were analysed by MLST. Strains belonging to SCCmec type III and IV were sequenced for their ccrAB gene of allotypes 3 and 2, respectively. Results: Five types of SCCmec, types I, III, IV, IV (paediatric) and V SCCmec, were found. The S. aureus strains belonged to sequence type (ST) 239 and the two S. epidermidis belonged to ST43 and ST60 respectively. High sequence conservation was observed for the ccrAB gene of allotypes 2 and 3. Conclusions: MRS isolates from cats and dogs demonstrate a similar diversity of SCCmec types to those found in human staphylococci and ST239-MRSA-III, a widely dispersed strain in human hospitals, was identified in diseased dogs.