RESUMO
Staphylococcus aureus is one of the most common causes of skin and soft tissue infections in health-care and community settings, but transmission of S. aureus in community-based populations is incompletely understood. S. aureus carriage phenotypes (persistent, intermittent, and non-carriers) were determined for households from Starr County, TX. Nasal swabs were collected from a cohort of 901 residents and screened for the presence of S. aureus. Isolated strains were spa-typed and assigned to clonal complexes. Of the 901 participants there were 134 pairs, 28 trios, 11 quartets, 3 quintets and 1 septet residing in the same household. There was a significant increase in "ever" carriers (persistent and intermittent carriers combined) in these households over that expected based on population frequencies (p = 0.029). There were 42 ever carrier pairs of individuals with 21 concordant for clonal complex type whereas only 4.7 were expected to be so (p = 6.9E-11). These results demonstrated clear aggregation of S. aureus carriage and concordance for strain types within households. As antibiotic-resistant S. aureus strains increase in community settings, it is important to better understand risk factors for colonization, mechanisms of transmission, clonal complexes present, and the role of household concordance/transmission.
