title: High diversity of genetic lineages and virulence genes in nasal Staphylococcus aureus isolates from donkeys destined to food consumption in Tunisia with predominance of the ruminant associated CC133 lineage.
abstract: BACKGROUND
  The objective of this study was to determine the genetic lineages and the incidence of antibiotic resistance and virulence determinants of nasal Staphylococcus aureus isolates of healthy donkeys destined to food consumption in Tunisia.
  
  
  RESULTS
  Nasal swabs of 100 donkeys obtained in a large slaughterhouse in 2010 were inoculated in specific media for S. aureus and methicillin-resistant S. aureus (MRSA) recovery. S. aureus was obtained in 50% of the samples, being all of isolates methicillin-susceptible (MSSA). Genetic lineages, toxin gene profile, and antibiotic resistance mechanisms were determined in recovered isolates. Twenty-five different spa-types were detected among the 50 MSSA with 9 novel spa-types. S. aureus isolates were ascribed to agr type I (37 isolates), III (7), II (4), and IV (2). Sixteen different sequence-types (STs) were revealed by MLST, with seven new ones. STs belonging to clonal clomplex CC133 were majority. The gene tst was detected in 6 isolates and the gene etb in one isolate. Different combinations of enterotoxin, leukocidin and haemolysin genes were identified among S. aureus isolates. The egc-cluster-like and an incomplete egc-cluster-like were detected. Isolates resistant to penicillin, erythromycin, fusidic acid, streptomycin, ciprofloxacin, clindamycin, tetracycline, or chloramphenicol were found and the genes blaZ, erm(A), erm(C), tet(M), fusC were identified.
  
  
  CONCLUSIONS
  The nares of donkeys frequently harbor MSSA. They could be reservoirs of the ruminant-associated CC133 lineage and of toxin genes encoding TSST-1 and other virulence traits with potential implications in public health. CC133 seems to have a broader host distribution than expected.
authors.affiliation: Laboratoire des Microorganismes et Biomolécules Actives, Faculté desSciences de Tunis, Université Tunis-El Manar, Tunis 2092, Tunisia.
authors.forename: Haythem
authors.initials: H
authors.lastname: Gharsa
authors.forename: Rym
authors.initials: R
authors.lastname: Ben Sallem
authors.forename: Karim
authors.initials: K
authors.lastname: Ben Slama
authors.forename: Elena
authors.initials: E
authors.lastname: Gómez-Sanz
authors.forename: Carmen
authors.initials: C
authors.lastname: Lozano
authors.forename: Ahlem
authors.initials: A
authors.lastname: Jouini
authors.forename: Naouel
authors.initials: N
authors.lastname: Klibi
authors.forename: Myriam
authors.initials: M
authors.lastname: Zarazaga
authors.forename: Abdellatif
authors.initials: A
authors.lastname: Boudabous
authors.forename: Carmen
authors.initials: C
authors.lastname: Torres
mesh_terms: D000003:Abattoirs; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004197:Disease Reservoirs / Q000382:microbiology / Q000662:veterinary; D024881:Drug Resistance, Bacterial; D018397:Equidae; D014644:Genetic Variation; D009666:Nose / Q000382:microbiology; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D013211:Staphylococcus aureus / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*; D014416:Tunisia / Q000453:epidemiology; D014774:Virulence
chemical_list: D000900:Anti-Bacterial Agents