Background: We characterized 100 USA100 epidemic MRSA from individuals in the community with no known healthcare-associated risk factors.
Findings: Molecular epidemiology demonstrated 21 pulsed-field types and six spa types. SCCmec typing demonstrated that all of the strains possess the type II cassette. The staphylococcal enterotoxin D virulence gene was also present.
Conclusion: Characterization of USA100 MRSA in the community illustrated the importance of nasal carriage, and the genetic diversity of the USA100 clone.
Keywords: MRSA; PFGE; Spa; Staphylococcus; USA100.