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Home Eurosurveillance Weekly Release  2007: Volume 12/ Issue 43 Article 1
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Eurosurveillance, Volume 12, Issue 43, 25 October 2007

Citation style for this article: Ruppitsch W, Stöger A, Schmid D, Fretz R, Indra A, Allerberger F, Witte W. Occurrence of the USA300 community-acquired Staphylococcus aureus clone in Austria. Euro Surveill. 2007;12(43):pii=3294. Available online:

Occurrence of the USA300 community-acquired Staphylococcus aureus clone in Austria

W Ruppitsch1, A Stöger1, D Schmid1, R Fretz1, A Indra1, F Allerberger (, W Witte2

1. Österreichische Agentur für Gesundheit und Ernährungssicherheit (Austrian Agency for Health and Food Safety - AGES), Vienna, Austria
2. Robert Koch-Institut, Berlin, Germany

Methicillin-resistant Staphylococcus aureus isolates are emerging as significant pathogens in the community. There are substantial differences between community-associated MRSA (CA-MRSA) and healthcare-associated MRSA (HA-MRSA) in terms of staphylococcal chromosome cassette (SCC) mec types, distribution of toxin genes and antimicrobial susceptibility [2]. CA-MRSA strains often carry a smaller methicillin resistance cassette (i.e. SCCmecIV or SCCmecV) and the Panton–Valentine leukocidin (PVL) genes lukS-lukV, and are commonly more susceptible to non-beta-lactam antibiotics [1]. PVL-producing MRSA cause mostly skin and soft tissue infections, but can also cause severe invasive disease, including necrotizing pneumonia [3,4]. Data indicate a higher prevalence of CA-MRSA in young people, and several cases in children have been described [2]. In Europe, the frequency of Panton-Valentine leukocidin (PVL)-positive CA-MRSA is about 3% of all isolates tested, with ST80 (spa type t044) being the most frequent CA-MRSA [5]. In the United States, clone "USA300" ST8 (spa type t008) as designated by the Centers for Disease Control and Prevention (CDC), is responsible for the majority of community-acquired infections causing major public health problems [6]. The occurrence of USA300 ST8 (t008) has recently been reported in several European countries [7-13]. Due to the pronounced spreading capacity of the USA 300 clone, early detection is essential for preventing its further diffusion in Europe.
This paper reports nine USA300 isolates found to date in Austria.

Since 2005, the National Reference Laboratory for Staphylococci at the Austrian Agency for Health and Food Safety has offered typing of MRSA isolates free of charge. To date, sequence analysis of the variable X-region of the protein A gene (spa), and testing for the Panton-Valentine leukocidin genes lukS-lukF (PVL) and for mecA have been performed on approximately 1,500 MRSA isolates. Detection of the mecA gene and of the PVL gene was performed in a duplex PCR as described by Stöger et al. [14]. The SCCmec type was determined by a multiplex PCR protocol as described by Oliveira et al. [15]. Molecular typing of the isolates by Multilocus Sequence Typing (MLST) was done as described by Enright et al. [16] and spa typing as described by Ruppitsch et al. [17]. Multiplex PCR-based agr grouping was performed as described by Moore and Lindsay [18]. The presence of the ACME gene cluster, another USA 300 associated genetic marker, was detected by PCR as described by Diep et al. [19]. SmaI macrorestriction analysis was performed according to the harmonised pulsed-field gel electrophoresis protocol using the proposed guidelines for gel image analysis as described by Murchan et al. [20].

Antimicrobial susceptibility patterns against gentamicin, erythromycin, clindamycin, tetracycline, chloramphenicol, vancomycin, teicoplanin, ciprofloxacin, sulfamethoxazole, rifampin, quinupristin-dalfopristin, and linezolid were determined by disk diffusion test applying CLSI-criteria and against mupirocin, fosfomycin, and fusidic acid according to instructions provided by the drug producers [21].

Of the approximately 1,500 MRSA isolates tested, nine were of spa type t008, harboured the PVL gene and the SCCmec IVa genetic element, and yielded the USA300 PFGE pattern. In accordance with the USA300 genotype, all nine isolates belonged to the agrI group and seven harbored the ACME gene cluster. Two isolates have lost the ACME gene cluster as determined by detection of the arcA gene by PCR [19].

These nine Austrian isolates of USA300 were submitted by five hospital laboratories and obtained from samples taken from eight patients with community-acquired infections and from one nasal swab taken from an asymptomatic carrier during contact tracing. The eight patients (five of them male) had a median age of 49 years (range 20-76) and suffered from various soft tissue infections (Table). None of the cases was lethal.

Epidemiological links to America could be shown for three of the eight patients: Isolate D was obtained from a 52-year-old Austrian postal worker employed in a parcel centre processing the incoming mail from the United States. Isolate G was taken from a 20-year-old US citizen who attended university courses in Austria. Isolate I belonged to a 26-year-old Austrian who suffered a cutaneous infection after he had been bitten by an insect during his vacation in Central America.

Besides general resistance to the beta-lactam antibiotics, the nine isolates showed in vitro resistance against erythromycin. Five isolates were resistant to ciprofloxacin and moxifloxacin, four other isolates showed intermediate resistance to ciprofloxacin. The isolate G obtained from the American student was also resistant to tetracycline (Table).

As a result of the pronounced capacity of USA300 to spread, early detection may be essential for preventing its diffusion in Europe. We have demonstrated the occurrence of USA300 in seven Austrian patients and one asymptomatic carrier, resident in Vienna, Lower Austria, and Salzburg, i.e. in three of the nine Austrian provinces.

CA-MRSA infections are not currently covered by Austria’s infectious disease control laws; there is no mandatory reporting and public health officers have no legal mandate to investigate occurrences of CA-MRSA infections. We feel that public health authorities should be prepared for CA-MRSA outbreaks and make ready the legal requirements necessary for outbreak control. A successful termination of a large furunculosis outbreak in Germany due to lukS-lukF-positive S. aureus by decolonisation strategy, including mupirocin nasal ointment and disinfecting wash solution, has been recently described by Wiese-Posselt et al. [22].

  1. Vandenesch F, Naimi T, Enright MC, Lina G, Nimmo GR, Heffernan H, et al. Community-acquired methicillin-resistant Staphylococcus aureus carrying Panton-Valentine leukocidin genes: worldwide emergence. Emerg Infect Dis 2003;9:978-984.
  2. Naimi TS, LeDell KH, Como-Sabetti K et al. Comparison of community- and healthcare-associated methicillin-resistant Staphylococcus aureus infection. JAMA 2003; 290: 2976–2984.
  3. Lina G, Piemont Y, Godail-Gamot F, Bes M, Peter MO, Vandenesch F, et al. Involvement of Panton-Valentine leukocidin–producing Staphylococcus aureus in primary skin infections and pneumonia. Clin Infect Dis 1999; 29:1128–1132
  4. King MD, Humphrey BJ, Wang YF, Kourbatova EV, Ray SM and Blumberg HM. Emergence of Community-Acquired Methicillin-Resistant Staphylococcus Aureus USA 300 Clone as the Predominant Cause of Skin and Soft-Tissue Infections. Annals of Int Med 2006;144:309-317
  5. Witte W, Braulke C, Cuny C, Strommenger B, Werner G, Heuck D, et al. Emergence of methicillin-resistant Staphylococcus aureus with Panton-Valentine leukocidin genes in central Europe. Eur J Clin Microbiol Infect Dis 2005; 24:1-5
  6. McDougal LK, Steward CD, Killgore GE, Chaitram JM, McAllister SK, Tenover FC. Pulsed-field gel electrophoresis typing of oxacillin-resistant Staphylococcus aureus isolates from the United States: establishing a national database. J Clin Microbiol 2003; 41:5113-5120
  7. Witte W, Cuny C, Strommenger B, Nübel U. Community MRSA ST8 (“USA300”) has arrived in Central Europe. Abstract 0119, 25th ECCMID, Munich, 31 March – 3 April, 2007
  8. Larsen AR, Stegger M, Goering RV, Sørum M, Skov R. Emergence and dissemination of the methicillin resistant Staphylococcus aureus USA300 clone in Denmark (2000-2005). Euro Surveill 2007; 20; 12(2). Available from:
  9. Wannet WJB, Heck MEOC, Pluister GN, Spalburg E, van Santen MG, et al. Panton-Valentine leukocidin positive MRSA in 2003: the Dutch situation. Euro Surveill 2004; 9:28-29. Available from:
  10. Kearns AM, Ganner M, Hill RLR, East C, McCormick Smith I, et al. Community-associated MRSA ST8-SCCmecIVa (USA-300): experience in England and Wales. Abstract 0118, 25th ECCMID, Munich, 31 March – 3 April, 2007
  11. Tietz A, Frei R, Widmer AF. Transatlantic spread of the USA300 clone of MRSA. N Engl J Med 2000; 353:532-533 15.
  12. Krziwanek K, Luger C, Sammer B, Stumvoll S, Stammler M, Metz-Gercek S, et al. PVL-positive MRSA in Austria. Eur J Clin Microbiol Infect Dis 2007
  13. Denis O, Deplano A, De Beenhouwer H, Hallin M, Huysmans G, Garrino M, et al. Polyclonal emergence and importation of community-acquired methicillin-resistant Staphylococcus aureus strains harbouring Panton-Valentine leukocidin genes in Belgium. J Antimicrob Chemother 2005; 56:1103
  14. Stoeger A, Gonano M, Pietzka A, Allerberger F, Wagner M, Ruppitsch W Comparative molecular analysis of veterinary, dairy, and clinical Staphylococcus aureus isolates by spa typing and amplification of the mecA and the PVL genes. Abstract P1301, 25th ECCMID, Munich, 31 March – 3 April, 2007
  15. Oliveira DC, de Lencastre H. Multiplex PCR strategy for rapid identification of structural types and variants of the mec element in methicillin-resistant Staphylococcus aureus. Antimicrob Agents Chemother 2002;46:2155-2161
  16. Enright MC, Day NPJ, Davies CE, Peacock SJ, Spratt BJ. Multilocus sequence typing for the characterization of methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) clones of Staphylococcus aureus. J. Clin. Microbiol. 2000;38:1008-15.
  17. Ruppitsch W, Indra A, Stoeger A, Mayer B, Stadlbauer S, Wewalka G, et al. Classifying spa types in complexes improves interpretation of typing results for methicillin-resistant Staphylococcus aureus. J Clin Microbiol 2006; 44:2442-2448
  18. Moore PC, Lindsay JA. Genetic variation among hospital isolates of methicillin-sensitive Staphylococcus aureus: evidence for horizontal transfer of virulence genes.J Clin Microbiol 2001; 39:2760-2767
  19. Diep BA, Gill SR, Chang RF, Phan TH, Chen JH, Davidson MG, et al. Complete genome sequence of USA300, an epidemic clone of community-acquired methicillin-resistant Staphylococcus aureus. Lancet 2006; 367:731-739
  20. Murchan S, Kaufmann ME, Deplano A, de Ryck R, Struelens M, Zinn CE, et al. Harmonization of pulsed-field gel electrophoresis protocols for epidemiological typing of strains of methicillin-resistant Staphylococcus aureus: a single approach developed by consensus in 10 European laboratories and its application for tracing the spread of related strains. J Clin Microbiol 2003;41:1574-1585
  21. Clinical and Laboratory Standards Institute. Performance Standards for Antimicrobial Susceptibility Testing; Sixteenth Informational Supplement. CLSI document M100-S16 (ISBN 1-56238-588-7). Clinical and Laboratory Standards Institute, 940 West Valley Road, Pennsylvania 19087-1898 USA 2006.
  22. Wiese-Posselt M, Heuck D, Draeger A, Mielke M, Witte W, Ammon A, et al. Successful termination of a furunculosis outbreak due to lukS-lukF-positive, methicillin-susceptible Staphylococcus aureus in a German village by stringent decolonization, 2002-2005. Clin Infect Dis 2007; 44:e88-95.

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