title: Molecular epidemiology of methicillin-resistant Staphylococcus aureus isolated from children in a community with low antimicrobial pressure in Japan.
abstract: Sado Island in Japan is an area with low antimicrobial pressure. A total of 41 community-onset methicillin-resistant Staphylococcus aureus (MRSA) isolates were obtained from pediatric outpatients and healthy children between August 2009 and January 2012, and genotyping and antimicrobial susceptibility testing of the MRSA isolates were performed. Additionally, the sources of MRSA isolated from healthy 1-month-old neonates were assessed. All isolates were negative for the Panton-Valentine leukocidin genes. Our data showed a lower prevalence of staphylococcal cassette chromosome (SCC)mecII on Sado Island (31.7% in total and 46.7% in healthy carriage) than that in the other areas of Japan, suggesting that a low level of antimicrobial use may be related to a low SCCmecII carriage rate in the community. To our knowledge, this is the first report of sequence type (ST)81/SCCmecIVg strains as well as the novel ST strain (ST2180/SCCmecIVa) in Japan. In addition, we detected an arginine catabolic mobile element (ACME)-arcA-positive ST764/SCCmecIIa clone that could disseminate successfully in the community. Intrafamilial transmission was observed in neonates identified with the SCCmecIV MRSA strains, and these strains were genetically typed as community-associated MRSA; the transmission routes of the remaining SCCmecIIa MRSA (genetically typed as healthcare-associated MRSA) strains could not be defined. In this study, we have shown that multiple MRSA strains can circulate in a community even under low antimicrobial pressure.
authors.affiliation: Department of Pediatrics, Sado General Hospital, Niigata, Japan. ootsukataketo＠hotmail.com
authors.forename: Taketo
authors.initials: T
authors.lastname: Otsuka
authors.forename: Hassan
authors.initials: H
authors.lastname: Zaraket
authors.forename: Koyata
authors.initials: K
authors.lastname: Fujii
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Masuda
authors.forename: Kenichi
authors.initials: K
authors.lastname: Komiyama
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Shirai
authors.forename: Atsushi
authors.initials: A
authors.lastname: Iwaya
authors.forename: Minoru
authors.initials: M
authors.lastname: Okazaki
mesh_terms: D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000382:microbiology* / Q000635:transmission; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007564:Japan / Q000453:epidemiology; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D058889:Molecular Typing; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology* / Q000635:transmission
chemical_list: D000900:Anti-Bacterial Agents