Quantitative analysis used in MRSA study

Scientists have used quantitative analysis processes to determine the genetic relatedness of Western Australian community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) clones within different multilocus sequence type (MLST) clonal clusters.

CA-MRSA is now the predominant strain of MRSA isolated in the state of Western Australia, with the team from Royal Perth Hospital aiming to gain insight into the frequency of S.aureus SCCmec acquisition within a region.

The study, published in BMC Microbiology, found that the CA-MRSA population in Western Australia is genetically diverse and has some 83 unique pulsed-field gel electrophoresis strains, 46 MLSTs of which have been characterised.

It determined that although SCCmec IV and V are the predominant SCCmec elements, SCCmec VIII and several novel and composite SCCmec elements are present.

"Only three clones have successfully adapted to the Western Australian community environment. These data suggest the successful evolution of a CA-MRSA clone may not only depend on the mobility of the SCCmec element but also on other genetic determinants," the report concluded.