Genetic Characterization of , , and Coagulase-Negative Staphylococci Colonizing Oral Cavity and Hand of Healthy Adults in Northern Japan.

The spread of methicillin resistance and virulence among staphylococci in the community poses a public health concern. In this study, we investigated the prevalence of species colonizing the oral cavity and hand (skin) of healthy university students and their phenotypic and genetic characteristics in northern Japan. Among a total of 332 subjects, 6 and 110 methicillin-resistant and susceptible (MRSA and MSSA, respectively) isolates were recovered from 105 subjects. MRSA isolates were genotyped as CC5, CC8, CC45, and CC59 with SCC-IIa or IV, among which an isolate of ST6562 (single-locus variant of ST8) harbored SCC-IVa, PVL genes and ACME-I, which are the same traits as the USA300 clone. ST1223 was isolated from the oral cavity and hand of a single student. Coagulase-negative (CoNS) was recovered from 154 subjects (172 isolates), and classified into 17 species, with being the most common (38%), followed by (24%) and (15%), including nine -positive isolates. was differentiated into seven clusters/subclusters, and genetic factors associated with the NRCS-A clone (, , ) were detected in 10-21% of isolates. The colonization of the USA300-like MRSA variant and with the traits of the NRCS-A clone in healthy individuals was noteworthy.