MRSA colonization is presumed to precede infection. However, although MRSA is now a frequent cause of skin and soft-tissue infection, the point prevalence of colonization in the general population is low. Of 9004 persons in the United States who were screened with the use of nasal cultures in 2004, only 1.5% were found to be colonized with MRSA, with community-associated strains accounting for only 19.7% of the MRSA isolates; 28.6% of the screened persons were colonized with methicillin-susceptible S. aureus.