title: Elimination of biofilm and microbial contamination reservoirs in hospital washbasin U-bends by automated cleaning and disinfection with electrochemically activated solutions.
abstract: BACKGROUND
  Washbasin U-bends are reservoirs of microbial contamination in healthcare environments. U-Bends are constantly full of water and harbour microbial biofilm.
  
  
  OBJECTIVE
  To develop an effective automated cleaning and disinfection system for U-bends using two solutions generated by electrochemical activation of brine including the disinfectant anolyte (predominantly hypochlorous acid) and catholyte (predominantly sodium hydroxide) with detergent properties.
  
  
  METHODS
  Initially three washbasin U-bends were manually filled with catholyte followed by anolyte for 5min each once weekly for five weeks. A programmable system was then developed with one washbasin that automated this process. This U-bend had three cycles of 5min catholyte followed by 5min anolyte treatment per week for three months. Quantitative bacterial counts from treated and control U-bends were determined on blood agar (CBA), R2A, PAS, and PA agars following automated treatment and on CBA and R2A following manual treatment.
  
  
  RESULTS
  The average bacterial density from untreated U-bends throughout the study was >1×10(5) cfu/swab on all media with Pseudomonas aeruginosa accounting for ∼50% of counts. Manual U-bend electrochemically activated (ECA) solution treatment reduced counts significantly (<100cfu/swab) (P<0.01 for CBA; P<0.005 for R2A). Similarly, counts from the automated ECA-treatment U-bend were significantly reduced with average counts for 35 cycles on CBA, R2A, PAS, and PA of 2.1±4.5 (P<0.0001), 13.1±30.1 (P<0.05), 0.7±2.8 (P<0.001), and 0 (P<0.05) cfu/swab, respectively. P. aeruginosa was eliminated from all treated U-bends.
  
  
  CONCLUSIONS
  Automated ECA treatment of washbasin U-bends consistently minimizes microbial contamination.
authors.affiliation: Facilities Department, Dublin Dental University Hospital, Lincoln Place, Dublin 2, Ireland.
authors.forename: J S
authors.initials: JS
authors.lastname: Swan
authors.affiliation: Microbiology Research Unit, Division of Oral Biosciences, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Lincoln Place, Dublin 2, Ireland.
authors.forename: E C
authors.initials: EC
authors.lastname: Deasy
authors.affiliation: Microbiology Research Unit, Division of Oral Biosciences, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Lincoln Place, Dublin 2, Ireland.
authors.forename: M A
authors.initials: MA
authors.lastname: Boyle
authors.affiliation: Department of Microbiology, University of Dublin, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: R J
authors.initials: RJ
authors.lastname: Russell
authors.affiliation: Microbiology Research Unit, Division of Oral Biosciences, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Lincoln Place, Dublin 2, Ireland.
authors.forename: M J
authors.initials: MJ
authors.lastname: O'Donnell
authors.affiliation: Microbiology Research Unit, Division of Oral Biosciences, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Lincoln Place, Dublin 2, Ireland. Electronic address: david.coleman@dental.tcd.ie.
authors.forename: D C
authors.initials: DC
authors.lastname: Coleman
mesh_terms: D001331:Automation / Q000379:methods; D001419:Bacteria / Q000187:drug effects*; D058491:Bacterial Load; D018441:Biofilms / Q000187:drug effects*; D004202:Disinfectants / Q000494:pharmacology*; D004203:Disinfection / Q000379:methods*; D055664:Electrochemical Techniques / Q000379:methods*; D006761:Hospitals; D006997:Hypochlorous Acid / Q000494:pharmacology; D012972:Sodium Hydroxide / Q000494:pharmacology; D012996:Solutions / Q000494:pharmacology*; D014871:Water Microbiology
chemical_list: D004202:Disinfectants; D012996:Solutions; D012972:Sodium Hydroxide; D006997:Hypochlorous Acid
keywords: Anolyte; Biofilm; Catholyte; Electrochemically activated solutions; Pseudomonas aeruginosa; Washbasin U-bends