Prevalence of decreased susceptibility to triclosan in isolates from animals and humans and association with multiple drug resistance

Justin L. Copitch (1) , Rebekah N. Whitehead (1) , Mark A. Webber (1)

1 University of Birmingham [Birmingham]

Previous laboratory studies have implicated triclosan as a possible selective force driving resistance to multiple antibiotics and have identified a number of triclosan resistance mechanisms in . The aim of this work was to determine the prevalence of decreased susceptibility to triclosan in a panel of human and animal isolates of and to identify the mechanisms of triclosan resistance in these strains. Over 400 animal and human isolates of non-typhoidal were screened for decreased susceptibility to triclosan and a panel of antibiotics. The prevalence of decreased susceptibility to triclosan was ca. 4%. Of the isolates with decreased triclosan susceptibility, 56% were multidrug-resistant (MDR) compared with 12% of triclosan-sensitive isolates. MDR and triclosan-resistant strains showed increased efflux activity compared with strains with reduced susceptibility to triclosan alone. No high-level triclosan resistance was seen in this panel of isolates. A reservoir of strains with low-level decreased triclosan susceptibility is present in animals and humans. These isolates are MDR as a result of generic mechanisms of antimicrobial resistance and do not carry specific mutations within .

Mots clés: Efflux; biocides; Salmonellosis

Justin L. Copitch, Rebekah N. Whitehead, Mark A. Webber. Prevalence of decreased susceptibility to triclosan in isolates from animals and humans and association with multiple drug resistance. International Journal of Antimicrobial Agents, 2010, 36 (3), pp.247. ⟨10.1016/j.ijantimicag.2010.04.012⟩. ⟨hal-00608995⟩