title: Unusual spread of a penicillin-susceptible methicillin-resistant Staphylococcus aureus clone in a geographic area of low incidence.
abstract: We describe the unusual spread of a penicillin-susceptible methicillin-resistant Staphylococcus aureus (MRSA) clone in hospitals in western Switzerland, where the incidence of MRSA is usually low. During a 2-year period, this clone had been responsible for several outbreaks and had been isolated from >156 persons in 21 institutions. Molecular typing by pulsed-field gel electrophoresis (PFGE) demonstrated that all of these isolates belonged to the same clone. In 1 of the outbreaks, involving 30 cases, the clone was responsible for at least 17 secondary cases. In contrast, during the period of the latter outbreak, 9 other patients harboring different MRSA strains, as assessed by PFGE, were hospitalized in the same wards, but no secondary cases occurred. These observations suggest that this clone, compared with other MRSA strains, had some intrinsic factor(s) that contributed to its ability to disseminate and could thus be considered epidemic.
authors.affiliation: Division Autonome de Médecine Préventive Hospitalière, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland. Dominique.Blanc@chuv.hospvd.ch.
authors.forename: D S
authors.initials: DS
authors.lastname: Blanc
authors.forename: C
authors.initials: C
authors.lastname: Petignat
authors.forename: P
authors.initials: P
authors.lastname: Moreillon
authors.forename: J M
authors.initials: JM
authors.lastname: Entenza
authors.forename: M
authors.initials: M
authors.lastname: Eisenring
authors.forename: H
authors.initials: H
authors.lastname: Kleiber
authors.forename: A
authors.initials: A
authors.lastname: Wenger
authors.forename: N
authors.initials: N
authors.lastname: Troillet
authors.forename: C
authors.initials: C
authors.lastname: Blanc
authors.forename: P
authors.initials: P
authors.lastname: Francioli
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003428:Cross Infection / Q000382:microbiology*; D004269:DNA, Bacterial / Q000032:analysis; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D005843:Geography; D006785:Hospitals, University; D006801:Humans; D015994:Incidence; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D010406:Penicillins / Q000494:pharmacology*; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics; D013557:Switzerland / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D010406:Penicillins