One-year surveillance of methicillin-resistant Staphylococcus aureus nasal colonization and skin and soft tissue infections in collegiate athletes.

Objective: To determine the frequency and clinical importance of methicillin-resistant Staphylococcus aureus (MRSA) colonization in student athletes.

Design: Prospective observational cohort study.

Setting: A major university in the southeastern United States.

Participants: Student athletes participating in the men's football and women's lacrosse programs (N = 126). Main Exposure Monthly assessment of S aureus nasal colonization.

Main Outcome Measures: Trends in S aureus colonization over time and the occurrence of skin and soft tissue infections.

Results: Methicillin-resistant S aureus nasal colonization varied significantly through the athletic season (4%-23%), peaking during times of highest athletic activity. This increase in colonization was not associated with the development of an outbreak of skin and soft tissue infections, and no single MRSA clone emerged as a dominant isolate.

Conclusions: During the athletic season, there is a considerable burden of MRSA colonization in student athletes; however, colonization alone appears to be insufficient to trigger an outbreak of staphylococcal infections. A combination of distinct molecular characteristics in the organism and specific host factors may govern the development of staphylococcal disease.