Epidemiological typing of methicillin-resistant Staphylococcus aureus (MRSA): spa typing versus pulsed-field gel electrophoresis.
Molecular methods based on sequencing, such as spa typing, have facilitated epidemiological typing of bacterial isolates compared to the gold standard pulsed-field gel electrophoresis (PFGE), a technically more demanding method. We studied methicillin-resistant Staphylococcus aureus (MRSA) in 4 Swedish counties from 2003 through 2005, and compared spa typing and PFGE results to epidemiological data. Of 280 MRSA isolates, 91 were from sporadic cases and 189 were associated with 35 outbreaks. A total of 50 spa types and 74 PFGE patterns were detected. 60 (21%) of the MRSA isolates carried the Panton-Valentine leukocidin (PVL) genes. 12 of the PVL-positive MRSA were healthcare associated. 25 of the spa types and 31 of the PFGE patterns were associated with outbreaks. In 1 of the outbreaks we found isolates with different but closely related spa types, and in 6 of the outbreaks we observed isolates with different but related PFGE patterns. In this low-endemic setting, with outbreaks limited in time and place, we found spa typing to be a useful tool for epidemiological typing of MRSA, due to its rapidity, accessibility, ease of use, and standardized nomenclature.
Department of Clinical Microbiology, Division of Laboratory Medicine, County Hospital Ryhov, Jönköping, Sweden.
Sara
S
Melin
Sara
S
Melin
Sara
S
Haeggman
Sara
S
Melin
Sara
S
Haeggman
Barbro
B
Olsson-Liljequist
Maria
M
Sjölund
Peter A
PA
Nilsson
Barbro
B
Isaksson
Sture
S
Löfgren
Andreas
A
Matussek
D001427:Bacterial Toxins / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field / Q000379:methods*; D019353:Endemic Diseases; D005098:Exotoxins / Q000235:genetics; D005798:Genes, Bacterial; D006801:Humans; D007956:Leukocidins / Q000235:genetics; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology / Q000379:methods*; D017422:Sequence Analysis, DNA / Q000379:methods*; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D013205:Staphylococcal Protein A / Q000235:genetics; D013548:Sweden / Q000453:epidemiology
D001427:Bacterial Toxins; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin; D013205:Staphylococcal Protein A