title: Commercial mouthwashes are ineffective against oral MRSA biofilms.
abstract: OBJECTIVE
  The aim of this study was to evaluate and compare the activity of oral mouthwashes against biofilm forms of MRSA isolated from the oral cavity and the bloodstream.
  
  
  METHODS
  The time-kill kinetics efficacy of 7 over-the-counter mouthwashes were tested against 28 clinical MRSA biofilm isolates for 0.5, 1 and 2 min.
  
  
  RESULTS
  Treatments of MRSA biofilms formed by oral and bloodstream isolates were not significantly different, with mouthwashes displaying a rapid and modest anti-biofilm effect. None of the biofilm isolates were completely eradicated by the compounds tested, with a maximal killing of only approximately 70% shown by Corsodyl and Peroxyl. Maximum activity of all compounds tested was observed after 0.5 min. Fluorigard showed the poorest overall activity (57% reduction).
  
  
  CONCLUSIONS
  MRSA colonize the oral cavity, and are more prevalent in institutionalized persons and the elderly. Over-the-counter mouthwashes are ineffective at killing MRSA biofilms, which has infection control implications.
authors.affiliation: Institute of Healthcare Associated Infection, University of the West of Scotland, Ayr, UK.
authors.forename: Karen
authors.initials: K
authors.lastname: Smith
authors.forename: Douglas P
authors.initials: DP
authors.lastname: Robertson
authors.forename: David F
authors.initials: DF
authors.lastname: Lappin
authors.forename: Gordon
authors.initials: G
authors.lastname: Ramage
mesh_terms: D000504:Aloe; D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D016470:Bacteremia / Q000382:microbiology; D001431:Bacteriological Techniques; D001565:Benzoates / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D002594:Cetylpyridinium / Q000494:pharmacology; D002710:Chlorhexidine / Q000031:analogs & derivatives / Q000494:pharmacology; D004338:Drug Combinations; D024881:Drug Resistance, Bacterial; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007202:Indicators and Reagents; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D009055:Mouth / Q000382:microbiology*; D009067:Mouthwashes / Q000494:pharmacology*; D028321:Plant Preparations / Q000494:pharmacology; D012459:Salicylates / Q000494:pharmacology; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology; D020947:Tea Tree Oil / Q000494:pharmacology; D013729:Terpenes / Q000494:pharmacology; D013778:Tetrazolium Salts; D013997:Time Factors; D014260:Triclosan / Q000494:pharmacology
chemical_list: D000891:Anti-Infective Agents, Local; D001565:Benzoates; D004338:Drug Combinations; D007202:Indicators and Reagents; D009067:Mouthwashes; D028321:Plant Preparations; C070868:Plax; D012459:Salicylates; D013729:Terpenes; D013778:Tetrazolium Salts; C059087:2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-((phenylamino)carbonyl)-2H-tetrazolium hydroxide; D012967:Sodium Dodecyl Sulfate; D014260:Triclosan; C057473:Listerine; D020947:Tea Tree Oil; D006861:Hydrogen Peroxide; D002594:Cetylpyridinium; C010882:chlorhexidine gluconate; D002710:Chlorhexidine