Variability of SCCmec elements in livestock-associated CC398 MRSA.

The most common livestock-associated lineage of methicillin-resistant Staphylococcus aureus (MRSA) in Western Europe is currently clonal complex (CC) 398. CC398-MRSA spread extensively across livestock populations in several Western European countries, and livestock-derived CC398-MRSA strains can also be detected in humans. Based on their SCCmec elements, different CC398 strains can be distinguished.

In vitro activity of ceftaroline against mecC-positive MRSA isolates.

Ceftaroline is a new cephalosporin with activity against methicillin-resistant Staphylococcus aureus (MRSA). A collection of 17 clinical and veterinary mecC-positive MRSA isolates was tested to evaluate the in vitro efficacy of ceftaroline against recently emerged mecC-MRSA isolates. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of ceftaroline for the 17 isolates were determined by broth microdilution using the methodology and interpretive criteria of the Clinical and Laboratory Standards Institute (CLSI).

[Phenotyping and microarray based genotyping of the antibiotic resistance of MRSA and MSSA from quarter milk samples of clinically healthy dairy cows].

The aim of this investigation was the comprehensive characterization of the in vitro antibiotic resistance profile and of the detectable resistance determinants in a systematic sampling of Staphylococcus aureus isolates from raw milk from clinically healthy cows. Quarter milk samples from all asymptomatic, milk producing cows from 34 Thuringian dairy herds were taken twice (n = 10421 and 10 417 respectively) and investigated bacteriologically. 189 out of the 1902 detected Staphylococcus aureus isolates were selected and established in terms of their resistance pattern using DNA-microarray analysis and agar diffusion test (AVID 1998) for the determination of the genotypic and phenotypic resistance, respectively.

Leukocidin genes lukF-P83 and lukM are associated with Taphylococcus aureus clonal complexes 151, 479 and 133 isolated from bovine udder infections in Thuringia, Germany.

Staphylococcus aureus is one of the most important causal agents of bovine mastitis. Population studies on bovine Staphylococcus aureus isolates have identified considerable genetic heterogeneity among strains causing mastitis. The aim of this study was to investigate the contribution of different clonal complexes and the occurrence of virulence factors and resistance determinants within bovine Staphylococcus aureus isolates.