Nasal carriage of Staphylococcus aureus in healthy humans with different levels of contact with animals in Tunisia: genetic lineages, methicillin resistance, and virulence factors

  • K. Ben Slama
  • H. Gharsa
  • N. Klibi
  • A. Jouini
  • C. Lozano
  • E. Gómez-Sanz
  • M. Zarazaga
  • A. Boudabous
  • C. Torres


Nasal swabs of 423 healthy humans who showed different levels of contact with animals (frequent, 168; sporadic, 94; no contact, 161) were obtained in Tunisia (2008–2009), and 99 of them presented other associated risk factors. Methicillin-resistant Staphylococcus aureus (MRSA) was detected in one of these 423 samples (0.24%), retrieved from a veterinarian. The MRSA isolate was mecA-positive, typed as ST80-t203-SCCmecIVc-agrIII, and contained tet(K), ant(6)-Ia, and aph(3′)-IIIa genes encoding tetracycline, streptomycin, and kanamycin resistance, respectively. This MRSA isolate also contained the lukF/lukS virulence gene encoding Panton–Valentine leukocidin. Fifty-four (12.8%) additional nasal samples contained methicillin-susceptible S. aureus (MSSA) and one isolate/sample was characterized. A high diversity of spa types (n = 43; 4 new) and pulsed-field gel electrophoresis (PFGE) types (n = 37) was detected among the 55 recovered S. aureus strains. The percentages of antimicrobial resistance/detected resistance genes were as follows: tetracycline [22%/tet(K)-tet(L)-tet(M)], erythromycin [5%/msrA], ciprofloxacin [14.5%], trimethoprim–sulfamethoxazole [2%/dfrA], streptomycin [11%/ant(6)-Ia], kanamycin [7%/aph(3′)-IIIa], amikacin [5%], and chloramphenicol [2%]. Four and two isolates carried the lukF/lukS and eta and/or etb genes, respectively, and always in individuals with contact with animals. Eleven isolates carried the tst gene and were recovered from individuals with different levels of contact with animals.


mecA Gene Aureus Isolate Toxic Shock Syndrome Toxin Inducible Clindamycin Resistance Oxacillin Resistance Screen Agar Base 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This study has been possible thanks to an Integrated Action and a Project financed by the Spanish Agency of International Development Cooperation (AECID) from the Ministerio de Asuntos Exteriores of Spain and from the Tunisian Ministry of Higher Education and Scientific Research. C. Lozano has a predoctoral fellowship from the Ministry of Science and Innovation and E. Gómez-Sanz has a predoctoral fellowship from Gobierno de La Rioja, Spain.

Part of the results of this manuscript has been presented at the 50th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC 2010), Boston, Massachusetts, USA, 12–15 September 2010.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • K. Ben Slama
    • 1
  • H. Gharsa
    • 1
  • N. Klibi
    • 1
  • A. Jouini
    • 1
  • C. Lozano
    • 2
  • E. Gómez-Sanz
    • 2
  • M. Zarazaga
    • 2
  • A. Boudabous
    • 1
  • C. Torres
    • 2
  1. 1.Laboratoire Microorganismes et Biomolécules Actives, Faculté des Sciences de TunisUniversité Tunis El ManarTunisTunisia
  2. 2.Área de Bioquímica y Biología MolecularUniversidad de La RiojaLogroñoSpain

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