title: Effect of treatment with an overheated dry-saturated steam vapour disinfection system on multidrug and extensively drug-resistant nosocomial pathogens and comparison with sodium hypochlorite activity.
abstract: BACKGROUND
  The development of portable steam generators has made disinfection of the environment more practical. This study assessed the "in vitro" ability of an overheated dry-saturated steam vapour system to kill multidrug and extensively-drug resistant nosocomial pathogens, defining the antimicrobial spectrum and the contact times compared with the activity of sodium hypochlorite.
  
  
  METHODS
  The antibacterial efficacy of the overheated dry-saturated steam vapour system and of sodium hypochlorite against nosocomial pathogen isolates: extensively drug-resistant Acinetobacter baumannii, Pseudomonas aeruginosa, carbapenemase-producing Klebsiella pneumoniae, methicillin-resistant Staphylococcus aureus, high-level aminoglycoside-resistant Enterococcus faecalis, Candida parapsilosis and Aspergillus fumigatus were assessed using a surface time-kill test carried out on glass surfaces, with or without bovine serum albumin (BSA).
  
  
  RESULTS
  The bactericidal activity of the overheated dry-saturated steam vapour system was observed at 180 °C after 5 min contact with or without BSA, using an initial inoculum of 10(9) CFU/mL. To reduce C. parapsilosis and A. fumigatus counts (from 10(7) CFU/mL), a longer contact time was necessary (7 min). In vitro tests with sodium hypochlorite at 5 % in the absence of an organic substance also resulted in an overall reduction in bacterial counts (from 10(9) CFU/mL) after 5 min of treatment. For mycotic challenge (10(7) CFU/mL), a longer contact time was necessary (7 min). In the presence of an organic substance, after 5 min, the hypochlorite reduced the viable count from 10(9) to 10(5) CFU/mL for all bacterial strains except E. faecalis that showed a reduction of 2 log units (10(9) to 10(7) CFU/mL). For C. parapsilosis and A. fumigatus, a 2 log unit reduction was observed after 7 min.
  
  
  CONCLUSIONS
  Steam disinfection of environmental surfaces using a portable steam generator is a practical and effective method that is not affected by the presence of organic matter.
authors.affiliation: Dipartimento di Sanità Pubblica, Università degli Studi di Napoli "Federico II", Via S. Pansini n.5, 80131, Naples, Italy. maria.bagattini@unina.it.
authors.forename: Maria
authors.initials: M
authors.lastname: Bagattini
authors.affiliation: Dipartimento di Sanità Pubblica, Università degli Studi di Napoli "Federico II", Via S. Pansini n.5, 80131, Naples, Italy. raffaellabuonocore@alice.it.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Buonocore
authors.affiliation: Dipartimento di Sanità Pubblica, Università degli Studi di Napoli "Federico II", Via S. Pansini n.5, 80131, Naples, Italy. mgiannou@libero.it.
authors.forename: Maria
authors.initials: M
authors.lastname: Giannouli
authors.affiliation: Dipartimento di Sanità Pubblica, Università degli Studi di Napoli "Federico II", Via S. Pansini n.5, 80131, Naples, Italy. mofima@tin.it.|Anestesia, Rianimazione e Terapia Intensiva, Seconda Università degli Studi di Napoli, Naples, Italy. mofima@tin.it.
authors.forename: Dario
authors.initials: D
authors.lastname: Mattiacci
authors.affiliation: Dipartimento di Sanità Pubblica, Università degli Studi di Napoli "Federico II", Via S. Pansini n.5, 80131, Naples, Italy. rossellabellopede@libero.it.
authors.forename: Rossella
authors.initials: R
authors.lastname: Bellopede
authors.affiliation: Dipartimento di Sanità Pubblica, Università degli Studi di Napoli "Federico II", Via S. Pansini n.5, 80131, Naples, Italy. nikgrim@libero.it.
authors.forename: Nicola
authors.initials: N
authors.lastname: Grimaldi
authors.affiliation: Dipartimento di Sanità Pubblica, Università degli Studi di Napoli "Federico II", Via S. Pansini n.5, 80131, Naples, Italy. avvnardone@gmail.com.
authors.forename: Antonio
authors.initials: A
authors.lastname: Nardone
authors.affiliation: Dipartimento di Sanità Pubblica, Università degli Studi di Napoli "Federico II", Via S. Pansini n.5, 80131, Naples, Italy. rafzarri@unina.it.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Zarrilli
authors.affiliation: Dipartimento di Sanità Pubblica, Università degli Studi di Napoli "Federico II", Via S. Pansini n.5, 80131, Naples, Italy. triassi@unina.it.
authors.forename: Maria
authors.initials: M
authors.lastname: Triassi
mesh_terms: D001419:Bacteria / Q000187:drug effects*; D003428:Cross Infection / Q000382:microbiology*; D003890:Desiccation; D004203:Disinfection / Q000379:methods*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D012973:Sodium Hypochlorite / Q000494:pharmacology*; D013227:Steam
chemical_list: D013227:Steam; D012973:Sodium Hypochlorite