Characteristics of Staphylococcus aureus strains isolated in Poland in 1996 to 2004 that were deficient in species-specific proteins

Occurrence, distribution and pattern analysis of methicillin resistant (MRSA) and methicillin sensitive (MSSA) Staphylococcus aureus on fomites in public facilities

Methicillin-resistant Staphylococcus aureus (MRSA) is a human pathogen incriminated as a causative agent of hospital nosocomial infections as well as a wide range of diseases in communities. This study was conducted to assess the occurrence and distribution of MRSA and methicillin-sensitive (MSSA) on different fomites in public facilities in northern Jordan and to determine their antibiograms, toxin genes profiles, as well as identify their genetic relatedness. A total of 2600 swabs were collected from 14 fomite surfaces in a variety of public facilities including hospitals, universities, schools, transportation sites, and market places. The identity of the 380 S. aureus isolates was confirmed. Among them, 158 (41.6%) were MRSA while the rest of the isolates, 222 (58.4%) were MSSA. MRSA isolates were recovered from all fomites sites. However, among the total collected samples, the percentages of MRSA in public facilities were significantly higher in hospitals and transportation fomites, while percentages of MRSA among fomites sites were higher in public reception sites, chairs, and toilet seats. Antibiotic resistance profiles indicated that 24.5% of the isolates were resistant to cefoxitin, oxacillin, and oxytetracycline. In contrast, only 3.95% were resistant to trimethoprim-sulfamethoxazole, and 15.3% were resistant to ciprofloxacin. Multidrug-resistant patterns were higher in MRSA than in MSSA isolates. There was no apparent difference in toxin gene profiles between MRSA and MSSA. Molecular analysis revealed 85 patterns and 16 clusters at a 9% mean similarity level. In conclusion, this study provides evidence for the potential of MRSA transmission via inanimate surfaces.

Screening of virulence genes in Staphylococcus aureus isolates from rabbits

<p><em>Staphylococcus aureus</em> is a versatile pathogen able to cause disease in both humans and animals. In rabbits, this bacterium infects animals of different ages, producing several purulent lesions. The ability of <em>S. aureus</em> to cause disease depends on a combination of virulence factors. The aim of this study was therefore to investigate the distribution of bacterial virulence determinants in 69 <em>S. aureus</em> isolates from rabbits. Some virulence factors (7 adhesins, 1 toxin and 1 protease) were positive in all rabbit <em>S. aureus</em> isolates analysed, while others (1 adhesin and 10 toxins) were always negative. The remaining virulence factors were more variable among isolates. An association between genotype and the different profiles of virulence factors was observed, but not with the type of lesion (P&lt;0.05). One strain of each genotype was further analysed by multilocus sequence typing, generating ST121, ST96 and ST2951, determining a greater number of enterotoxins in ST121 isolates compared to ST96 and ST2951 isolates, which could justify the different pathogenicity between strains. </p>

Molecular surveillance of Staphylococcus aureus colonization in a neonatal intensive care unit

In a survey of staphylococcal colonization, Staphylococcus aureus was detected in 7 of 67 infants (10%). Two of the infants (3%) carried methicillin-resistant S aureus (MRSA), revealing an unsuspected transmission of MRSA within the neonatal intensive care unit. Molecular surveillance of S aureus provided useful information to improve infection control practices.

Countrywide molecular survey of methicillin-resistant Staphylococcus aureus strains in Poland

The present investigation was undertaken to assess the proportion of methicillin-resistant Staphylococcus aureus (MRSA) strains among hospital-acquired isolates and to determine the clones of MRSA currently circulating in Poland by using a number of molecular techniques. Between January and May 2005, methicillin resistance was investigated among a total of 915 S. aureus isolates collected from 39 hospitals. A total of 208 (22.7%) isolates were positive for the mecA gene by PCR. The molecular characterization of MRSA isolates was carried out by the multiple-locus variable-number tandem repeat fingerprinting, pulsed-field gel electrophoresis, multilocus sequence typing, and staphylococcal chromosomal cassette mec (SCCmec) typing methods. The Hungarian (PFGE B; ST239, SCCmec type III [ST239-III]), Iberian (ST247-I), and Berlin (ST45-IV) clones were predominant, representing approximately 52.9, 11.5, and 10.0% of the MRSA isolates, respectively. A decline in the proportion of earlier MRSA clones, such as ST5-IV (a Pediatric clone), ST80-IV) (a Mediterranean clone), ST239-III (a Polish and Brazilian clone), and ST30-IV (a southwest Pacific clone) was observed. Additionally, the emergence of an MRSA clone with SCCmec type V, possibly representing a community-acquired strain, was observed in two hospitals during this study.