RESEARCH emerge as a community-acquired pathogen as a consequence of horizontal acquisition of the mecA gene by a previously sus- ceptible S. aureus strain type. Acknowledgments We thank Ritva Scotford and Elina Siren for their excellent tech- nical assistance, Marja Ratia for collecting the patient identity infor- mation and sending the questionnaires, and Teemu Möttönen for assistance in data management. We also thank the infection control nurses in Finnish hospitals for their contribution in gathering the patient background data and continuous cooperation in the field of Methicillin-resistant Staphylococcus aureus research. The recognition of UK EMRSA-16, UK EMRSA-15, and Iberian clone in Finland was achieved by the Harmony Project (www.phls.org.uk/Interna- tional/Harmony/Harmony.htm). Ms. Salmenlinna works as a scientist in the laboratory of Hospital Bacteriology at the National Public Health Institute (KTL) in Helsinki, Finland. 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