Identification and molecular epidemiological analysis of emerging clones of community-acquired MRSA obtained from odontogenic infection disease

2015 Fiscal Year Final Research Report

• Project/Area Number: 25463260
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Social dentistry
• Research Institution: Health Sciences University of Hokkaido
• Principal Investigator: HIROSE MINA 北海道医療大学, 歯学部, 准教授 (10265077)
• Co-Investigator(Kenkyū-buntansha): FUKUDA ATSUSHI 北海道医療大学, 歯学部, 助教 (10453276) ; MURATA YUKIE 北海道医療大学, 歯学部, 助教 (90455676)
• Co-Investigator(Renkei-kenkyūsha): KOBAYASHI NOBUMICHI 札幌医科大学, 医学部, 教授 (80186759)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: MRSA / 小児 / 唾液 / MLST

Outline of Final Research Achievements

A total of 254 staphylococcal isolates were collected from oral cavity of 526 healthy children were analysed. Multiplex PCR was performed to detect mecA, PVL genes and ACME-arcA gene. SCCmec typing was determined for all isolates, and coagulase gene (coa) genotype was assigned to all S. aureus. ST (sequence type) based on MLST scheme, agr type, prevalence of virulence factors, antibiotic susceptibility were analysed for the selected 20 S. aureus isolates.
The most prevalent species was S. aureus (n=147), followed by S. epidermidis (n=89), S. warneri (n=12), S. haemolyticus (n=4), and S. hominis (n=2). The mecA was detected in 6.1% of S. aureus, 60.7% of S. epidermidis, and 8.3% in S. warneri, and SCCmec was typed as IV (75%) or V, with IVa subtype being dominant. MRSA were classified into ST1, ST5, ST8, ST89, ST120. Two ST8 were SCCmec IVl, coa-IIIa, and had sec, sei, sel, tst-1, and spj/sasL gene which is characteristic trait for an emerging Japanese MRSA clone.

Free Research Field

小児歯科学