Asian Program

Japanese

Data

Former Fellows

Dissertation Abstracts

Thailand

  A description of SCCmec elements carried by 615 methicillin-resistant Staphylococcus aureus MRSA strains isolated in eleven Asian countries is reported, and a novel nomenclatural system based on their structures is proposed. The 615 strains were classified as type-3A (370 strains), type-2A (207), type-2B (32), type-1B (1), and nontypeable (5). The previously-reported type-III SCCmec (GenBank/EMBL/DDBJ accession No. AB037671) carried by the MRSA strain 85/2082 was ascertained to be composed of two SCC elements, type-3A SCCmec and SCCmercury. By PCR analysis indicated that 310 of 370 type-3A SCCmec strains carried both SCC elements. These strains were prevalent in eight countries: Thailand, Sri Lanka, Indonesia, Vietnam, Philippines, Saudi Arabia, India, and Singapore. The remailing 60 type-3A SCCmec strains differed with respect to the left extremity polymorphism or to the presence of ccrC.Among these, two were identified as carrying only type-3A SCCmec elements, but their left extremities differed. Type-2A SCCmec strains predominated in Korea and Japan, although the frequency of the presence of ant(4')-1 gene downstream of mecA varied (53 % for Korean strains ; 93 % for Japanese strains). Various SCCmec elements were identified in the tested strains, and limited number were identified in their MLST genotypes. These data suggest that numerous MRSA clones are disseminated in Asian hospitals, and these consist of minor clones that are presumed to have arisen locally and major clones that are presumed to have been introduced from other countries.