We found that clinical and epidemiological risk factors in persons hospitalized for CA S. aureus infection cannot reliably distinguish between MRSA and MSSA. Our findings have important implications for the choice of empirical antibiotic therapy for suspected S. aureus infections and for infection control.

Although it is believed patients with CA-MRSA skin infection may have more serious outcomes than those with CA-MSSA skin infection, we found similar outcomes in these 2 groups after hospital discharge. Clinical nonresponse at day 30 was associated with a lack of receipt of incision and drainage. Our data also suggest that close contacts of persons with CA-MRSA skin infection may have a higher likelihood of acquiring an infection.