We quantified methicillin-resistant Staphylococcus aureus (MRSA) carriage. The greater the log 10 count in samples from the nares, the greater the likelihood that other body sites had been colonized. Log 10 counts among body sites were correlated. The greatest sensitivity value (98%) was determined for the combined results from 2 sites: the nares and the groin.

Nasal swab specimens positive for MRSA had a geometric mean quantity of 794 CFU per swab, with great diversity in the quantity of MRSA at this anatomic site. Outpatient populations at high risk for MRSA carriage were elderly residents of long-term care facilities, HIV-infected outpatients, and outpatients receiving hemodialysis.

No abstract