Methicillin-resistant Staphylococcus aureus containing the Panton-Valentine leucocidin gene in Germany in 2005 and

Wolfgang Witte1, Birgit Strommenger, Christa Cuny

  • 1Robert Koch Institute, Wernigerode Branch, 38855 Wernigerode, Germany. wittew@rki.de

Abstract

Insights

Panton-Valentine leucocidin (PVL)-positive methicillin-resistant Staphylococcus aureus (MRSA) clonal lineages were identified. The USA300 clone, a community-associated MRSA (caMRSA), has arrived in Central Europe and is the second most frequent type.

Area of Science:

  • Microbiology
  • Molecular Epidemiology

Background:

  • Panton-Valentine leucocidin (PVL) is a toxin produced by some strains of Staphylococcus aureus.
  • Methicillin-resistant Staphylococcus aureus (MRSA) is a significant cause of healthcare-associated and community-associated infections.
  • Identifying the clonal lineages of PVL-positive MRSA is crucial for understanding its epidemiology.

Purpose of the Study:

  • To attribute PVL-positive MRSA to specific clonal lineages using molecular typing.
  • To investigate the presence and characteristics of the community-associated MRSA (caMRSA) USA300 clone in Central Europe.

Main Methods:

  • Analysis of 117 PVL-positive MRSA isolates from Germany using PFGE, spa typing, and multilocus sequence typing (MLST).
  • Characterization of SCCmec elements and PCR detection of specific genes (arcA, msr(A), mph(B)) and repeat units.

Main Results:

  • The predominant PVL-positive MRSA lineage was spa type t044/MLST ST80 (80 isolates).
  • Spa type t008/MLST ST8, characteristic of the USA300 caMRSA clone, was identified in 23 isolates, indicating its emergence in Central Europe.
  • Other spa types were found sporadically.

Conclusions:

  • PVL-positive MRSA ST80 remains the most frequent clone, but the USA300 clone (ST8) is emerging as the second most common.
  • Routine PCR detection methods can facilitate the identification of the USA300 clone in clinical settings.

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