ABSTRACT
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important nosocomial pathogens worldwide. This study was performed to investigate the characterization of MRSA isolated from healthy persons in Gwangju area. A total of 404 nasal swab samples was collected during October 2011 and May 2012 in Gwangu, Korea. A survey on MRSA was conducted with meat distributors (n=230), pre-school children (n=108), officers (n=66), respectively. To confirm the MRSA, polymerase chain reaction (PCR) for the S. aureus specific gene and mecA gene was performed. A total of 34 (8.4%) MRSA isolates was isolated from 404 nasal swab samples: 6.1% (14/230) from meat distributors, 16.7% (18/108) from pre-school children, and 3.0% (2/66) from officers samples, respectively. The most prevalent antimicrobial resistance observed in the MRSA isolates was to ampicillin 100% (34/34), followed by penicillin 97.1% (33/34), oxacillin 94.1% (32/34) and erythromycin 52.9% (18/34). All MRSA isolates were then characterized by panton-valentine leukocidin (pvl) gene detected by PCR, staphylococcal cassette chromosome mec (SCCmec) typing, and pulsed-field gel electrophoresis (PFGE) with Sma I digestion. 34 MRSA isolates from nasal carriage were pvl gene negative, SCCmec type IV; 73.5% (25/34), type II; 17.6% (6/34), type III; 2.9% (1/34), and untypable; 5.9% (2/34), respectively. 34 MRSA isolates showed 16 PFGE patterns. These results indicated that isolation rates of community-associated methicillin-resistant S. aureus (CA-MRSA) from healthy persons were low (8.4%), but continuous surveillance and monitoring should be performed to prevent the spread of MRSA in the community.
Subject(s)
Child , Humans , Adenosine , Ampicillin , Bacterial Toxins , Digestion , Electrophoresis, Gel, Pulsed-Field , Erythromycin , Exotoxins , Korea , Leukocidins , Meat , Methicillin Resistance , Methicillin-Resistant Staphylococcus aureus , Oxacillin , Penicillins , Polymerase Chain ReactionABSTRACT
Objective To investigate the drug resistance,source and molecular epidemiology of methicillin-resistant Staphyloccus aureus(MRSA)causing nosocomial infection. Methods Fifty-seven pathogenic MRSA strains were isolated from Beijing Tongren Hospital during 2007 and 2008.K-B method,MIC assay,multiple PCR,automatic repetitive element sequence-based PCR(REP-PCR)typing platform and DL MRSA Library were used to identify the resistant phenotypes,Panton-Valentine leukocidin gene (pvl)and REP-PCR types of the MRSA.Results All strains were classified as 6 antibiotic resistant phenotypes(a-f)based on the resistance to rifampin,clindamycin,levofloxacin and cotrimoxazole.The MRSAs with Staphylococcal cassette chromosome mec(SCCmec)Ⅲ and SCCmec Ⅱ accounted for 91.23% (52/57)and 5.26%(3/57)of all strains,respectively.Only one strain was pvl positive.All strains were typed as REP-A-F(6 types)and three single clones by automatic REP-PCR typing platform,in which REP-C was predominant(30/57,52.63%).Three out of 6 REP-D strains were from laryngology wards.The REP-C-SCCmec Ⅲ were genetically most close to the Brazilian clone-SCCmec Ⅲ in DL MRSA Library.Conclusion s REP-C-SCCmec Ⅲ-a type are the major epidemic hospital-associated MRSA and the REP-D-SCCmec Ⅲ-d is usually isolated from patients received laryngeal surgery. Automatic REP-PCR typingplatform combined with DL MRSA Library database is an effective approach to study the nosocomial infection.
ABSTRACT
Staphylococcal cassette chromosome mec (SCCmec) type and coagulase serotype are important epidemiologic factors in methicillin-resistant Staphylococcus aureus (MRSA). To investigate correlation between SCCmec type and coagulase serotype of MRSA, we analyzed SCCmec types of MRSA strains isolated from clinical sources and compared the results to coagulase serotypes and antimicrobial susceptibility patterns. A total of 108 MRSA isolates were classified into four SCCmec types: II (55.6%), IV (21.3%) III (13.0%) and IIIA (8.3%), and five coagulase serotypes: II (54.6%), IV (21.3%), V (18.5%) and VII (2.8%). All of coagulase type II, IV and V strains belonged to SCCmec type II, III/IIIA and IV, respectively. SCCmec types II, III and IIIA were multidrug resistant, whereas SCCmec type IV strains were non-multidrug resistant except beta-lactams and erythromycin. The data provide that there is a significant correlation between SCCmec types and phenotypic characteristic of coagulase serotypes.