title: A new UV-LED device for automatic disinfection of stethoscope membranes.
abstract: BACKGROUND
  Stethoscopes are widely used by doctors and nurses. Poor stethoscope hygiene is a potential source of nosocomial infection. This study aimed to propose an innovative solution, based on the latest advances in ultraviolet (UV) light-emitting diodes (LEDs), for disinfecting stethoscope membranes automatically and efficiently.
  
  
  METHODS
  Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis were sown on 28 stethoscope membranes and then transferred to Petri dishes. Treatment involved illuminating exposed Petri dishes with a UVC LED for 1 minute. For each microbe, the number of colony-forming units (cfu) at 36°C was compared in control and treated dishes using the Wilcoxon signed-rank test. The Kruskal-Wallis test was used to assess percent reductions in bacteria. Statistical significance was set at 99%.
  
  
  RESULTS
  A significant reduction in cfu counts after UV treatment (P < .01) was found for all bacteria: 85.5% for E faecalis, 87.5% for S aureus, 94.3% for E coli, and 94.9% for P aeruginosa . No significant differences in percent reduction in cfu were found between bacteria (P > .01).
  
  
  CONCLUSIONS
  The stethoscope, symbol of medicine and health care professionals, has been demonstrated to be a carrier of microorganisms. The treatment technique was effective and efficient in disinfecting the membranes. These promising results represent a step forward toward eliminating stethoscope membrane contamination with an innovative approach.
authors.affiliation: Laboratory of Environmental Hygiene, Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy. Electronic address: gabriele.messina@unisi.it.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Messina
authors.affiliation: Laboratory of Environmental Hygiene, Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy.
authors.forename: Sandra
authors.initials: S
authors.lastname: Burgassi
authors.affiliation: Monte dei Paschi Foundation of Siena, Siena, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Messina
authors.affiliation: Automatic Speech Recognition - Research (ASR-R), Siena, Italy.
authors.forename: Valerio
authors.initials: V
authors.lastname: Montagnani
authors.affiliation: Department of Medical Biotechnology, University of Siena, Siena, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Cevenini
mesh_terms: D001419:Bacteria / Q000302:isolation & purification* / Q000528:radiation effects*; D015169:Colony Count, Microbial; D004203:Disinfection / Q000379:methods*; D006801:Humans; D019023:Stethoscopes / Q000382:microbiology*; D013696:Temperature; D014466:Ultraviolet Rays
keywords: Biotechnology; Disinfection; Health care–associated infection; Stethoscope; UV-LED