title: Classifying spa types in complexes improves interpretation of typing results for methicillin-resistant Staphylococcus aureus.
abstract: A total of 382 isolates of methicillin-resistant Staphylococcus aureus originating from three Austrian regions and one adjacent Italian region (Vienna, Lower Austria, North Tyrol, and South Tyrol) were typed by DNA sequence analysis of the variable repeat region of the protein A gene (spa typing). The strain collection consisted of arbitrarily chosen isolates originating from clinical specimens taken in the years 2003 to 2005 at 17 hospitals. The most common spa types found were t001 (28.8% of all isolates), t190 (27.0%), t008 (14.1%), and t041 (11.3%). The 42 remaining spa types accounted for <or=2.4% each. The dominating spa types varied between the different regions. As short sequence DNA repeat units are unstable entities, the 46 spa types were classified into seven spa complexes with respect to short sequence repeat unit composition and organization. Such classification into complexes can provide additional information for the hospital epidemiologist, empowering one to differentiate the introduction of a new strain from mere variation of endemic spa types.
authors.affiliation: Austrian Agency for Health and Food Safety, Institute of Medical Microbiology and Hygiene, Spargelfeldstrasse 191, A-1226 Vienna, Austria. werner.ruppitsch@ages.at
authors.forename: Werner
authors.initials: W
authors.lastname: Ruppitsch
authors.forename: Alexander
authors.initials: A
authors.lastname: Indra
authors.forename: Anna
authors.initials: A
authors.lastname: Stöger
authors.forename: Barbara
authors.initials: B
authors.lastname: Mayer
authors.forename: Silke
authors.initials: S
authors.lastname: Stadlbauer
authors.forename: Günther
authors.initials: G
authors.lastname: Wewalka
authors.forename: Franz
authors.initials: F
authors.lastname: Allerberger
mesh_terms: D001317:Austria; D015373:Bacterial Typing Techniques / Q000379:methods*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D007558:Italy; D016106:Methicillin Resistance; D017720:Molecular Epidemiology; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics; D017422:Sequence Analysis, DNA; D013203:Staphylococcal Infections / Q000382:microbiology*; D013205:Staphylococcal Protein A / Q000235:genetics*; D013211:Staphylococcus aureus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D004269:DNA, Bacterial; D013205:Staphylococcal Protein A