title: Investigation of healthcare-acquired infections associated with Pseudomonas aeruginosa biofilms in taps in neonatal units in Northern Ireland.
abstract: BACKGROUND
  In December 2011 and early 2012 four neonates died from Pseudomonas aeruginosa bacteraemia in hospitals in Northern Ireland.
  
  
  OBJECTIVE
  To assess whether P. aeruginosa was associated with the neonatal unit taps and whether waterborne isolates were consistent with patient isolates.
  
  
  METHODS
  Thirty taps and eight flow straighteners from the relevant hospitals were categorized and dismantled into 494 components and assessed for aerobic colony and P. aeruginosa counts using non-selective and selective agars. P. aeruginosa isolates were typed by variable number tandem repeat (VNTR) analysis. Selected tap components were subjected to epifluorescence and scanning electron microscopy to visualize biofilm.
  
  
  RESULTS
  The highest P. aeruginosa counts were from the flow straighteners, metal support collars and the tap bodies surrounding these two components. Complex flow straighteners had a significantly higher P. aeruginosa count than other types of flow straighteners (P < 0.05). Highest aerobic colony counts were associated with integrated mixers and solenoids (P < 0.05), but there was not a strong correlation (r = 0.33) between the aerobic colony counts and P. aeruginosa counts. Representative P. aeruginosa tap isolates from two hospital neonatal units had VNTR profiles consistent with strains from the tap water and infected neonates.
  
  
  CONCLUSIONS
  P. aeruginosa was predominantly found in biofilms in flow straighteners and associated components in the tap outlets and was a possible source of the infections observed. Healthcare providers should be aware that water outlets can be a source of P. aeruginosa contamination and should take steps to reduce such contamination, monitor it and have strategies to minimize risk to susceptible patients.
authors.affiliation: Microbiology Services Division, Public Health England, Porton, Salisbury, UK. Electronic address: jimmy.walker@phe.gov.uk.
authors.forename: J T
authors.initials: JT
authors.lastname: Walker
authors.affiliation: Microbiology Services Division, Public Health England, Porton, Salisbury, UK.
authors.forename: A
authors.initials: A
authors.lastname: Jhutty
authors.affiliation: Microbiology Services Division, Public Health England, Porton, Salisbury, UK.
authors.forename: S
authors.initials: S
authors.lastname: Parks
authors.affiliation: Microbiology Services Division, Public Health England, Porton, Salisbury, UK.
authors.forename: C
authors.initials: C
authors.lastname: Willis
authors.affiliation: Microbiology Services Division, Public Health England, Porton, Salisbury, UK.
authors.forename: V
authors.initials: V
authors.lastname: Copley
authors.affiliation: Microbiology Services Division, Public Health England, Colindale, London, UK.
authors.forename: J F
authors.initials: JF
authors.lastname: Turton
authors.affiliation: Microbiology Services Division, Public Health England, Colindale, London, UK.
authors.forename: P N
authors.initials: PN
authors.lastname: Hoffman
authors.affiliation: Microbiology Services Division, Public Health England, Porton, Salisbury, UK.
authors.forename: A M
authors.initials: AM
authors.lastname: Bennett
mesh_terms: D058491:Bacterial Load; D018441:Biofilms / Q000254:growth & development*; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality; D060766:Drinking Water / Q000382:microbiology; D004783:Environmental Microbiology; D005453:Fluorescence; D005838:Genotype; D006268:Health Facilities; D006801:Humans; D008855:Microscopy, Electron, Scanning; D018598:Minisatellite Repeats; D058889:Molecular Typing; D009660:Northern Ireland / Q000453:epidemiology; D011552:Pseudomonas Infections / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality; D011550:Pseudomonas aeruginosa / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D013194:Staining and Labeling
chemical_list: D060766:Drinking Water
keywords: Flow straighteners; Neonatal units; Pseudomonas aeruginosa; Sensor taps