f Staphylococcus aureus bacteremia is common in both nosocomial and community settings, and the pathogenicity of the microbe depends upon a large repertoire of virulence factors. S. aureus bacteremia isolates (n ؍ 126) were characterized using DNA microarrays. Clonal complexes 5, 8, 15, 30, and 45 accounted for 74.6% of the isolates. We identified geographical differences in dominating clones and toxin gene profiles. One isolate was methicillin resistant. Potential associations between age and genotype were detected.