ABSTRACT
Objective To investigate the molecular epidemiology of Staphylococcus aureus in Yanbian area .Methods From March 2011 to June 2012 ,a total of 101 consecutive and non-duplicate strains of Staphylococcus aureus were collected from Yanbian Hospital .Genotypes of SCCmec ,spa,and multilocus sequence typing (MLST) were determined by PCR combined with DNA sequencing analysis .The pvl gene was detected by PCR .Results The most prevalent SCCmec type was type II (65 .0% ,39/60) ,followed by SCCmec type III (26 .7% ,16/60) .A total of 11 Spa types were identified for the MRSA strains ,including t2460 (55 .0% ,33/60) ,t030 (18 .3% ,11/60) ,t002 ,t324 ,and t632 (5 .0% ,3/60 each) .A total of 29 Spa types were identified for MSSA strains ,including t796 (14 .6% ,6/41) ,t309 (9 .8% ,4/41) ,and t126 (7 .3% ,3/41) . The pvl gene was identified in 5 stains .MRSA strains were classified into three types based on multilocus sequence typing (MLST) ,namely ST5 ,ST239 and ST72 .MLST-based MSSA types were more diverse ,including ST5 ,ST 25 ,ST 15 ,ST 59 ,ST 1 ,ST 7 ,ST 45 ,ST 22 ,and ST 188 .Conclusions ST5-MRSA-SCCmecII-t2460 and ST239-MRSA-SCCmecIII-t030 are the most prevalent MRSA clones in Yanbian area .Multiple prevalent MSSA clones are identified.
ABSTRACT
Objective To investigate the source and genetic background of methicillin-resistant Staphylococcus aureus in the year of 2006,in China. Methods From January to December 2006,a total number of 302 consecutive and non-repetitive methicillin-resistant Staphylococcus aureus were collected from 17 Teaching hospitals in 15 areas. Genotypes of SCCmec were determined by multiplex PCR and multilocus sequence typing (MLST) was used to type the house-keeping genes. The implementation of the spa typing method was straightforward,and the results obtained were reproducible,unambiguous,and easily interpreted. Results All areas but Dalian harbored SCCmec Ⅲ while Dalian harbored SCCmec Ⅱ most. There were two strains in Guangzhou,harboring SCCmec Ⅳ. There were four strains of sequence type(ST),with ST239 accounted for 46.7% and ST5 accounted for 44.4%. ST59 accounted for 6.7% and ST88 accounted for 2.2%. There were fourteen strains of Spa typing,with t30 accounted for 52.6% ; t37 accounted for 27.2% ; t2 accounted for 12.9% ; t632 accounted for 2.3% ; t437 accounted for 1.3% ; t570,t601 accounted for 0.7% ; t377,t459,t796,t899,t1152,t2649 accounted for 0.3% ; no-typing accounted for 0.3%,respectively,pvl gene was not detected. Conclusion The main clone strains were ST239-MRSA-SCCmec Ⅲ-t30,ST5-MRSA-SCCmec Ⅱ-t2,with unique geographic distributions across the whole nation.