Evaluation of a pulsed xenon ultraviolet light device for reduction of pathogens with biofilm-forming ability and impact on environmental bioburden in clinical laboratories

Photodiagnosis Photodyn Ther. 2020 Mar:29:101544. doi: 10.1016/j.pdpdt.2019.08.026. Epub 2019 Aug 24.

Abstract

Background: Biofilm-forming organisms can persist on surfaces in hospital clinical laboratories and potentially lead to nosocomial infections. Therefore, effective decontamination procedures are essential for reducing infections. In this study, we investigated an alternative to often ineffective manual cleaning methods, a pulsed xenon ultraviolet (PX-UV) light device. We evaluated PX-UV effect on biofilm formation ability of pathogens and also evaluated PX-UV effectiveness on environmental bioburden in clinical laboratories.

Methods: We selected and identified P. aeruginosa PA47, Staphylococcus aureus B1, and K. pnenumoniae CR52 from clinic isolates. Biofilm-forming ability and effectiveness of PX-UV in killing these biofilm forming strains on surfaces was evaluated. The central laboratory, the clinical microbiology laboratory, and the clinical immunology laboratory were chosen for testing environmental bioburden. Air samples and high-touch surface specimens in the three laboratories were obtained before and after routine manual cleaning, and after 6 min of PX-UV disinfection. The cultured microbes were then identified with MALDI- TOF-MS.

Results: We found that P. aeruginosa PA47, Staphylococcus aureus B1, and K. pnenumoniae CR52 were able to form robust biofilms, and that PX-UV significantly reduced colony counts of these strains on all surfaces tested. PX-UV reduced the bioburden of air samples and eliminated bioburden on surfaces. All microbes identified in the clinical laboratories were pathogenic and consisted of cocci, rods, and fungi.

Conclusions: The PX-UV device effectively reduced pathogens with biofilm-forming ability on surfaces, and the environmental bioburden was also significantly reduced by PX-UV. PX-UV is a viable option for protecting staff and decreasing rates of laboratory-acquired infections.

Keywords: Biofilm formation; Clinical laboratory; Laboratory-acquired infections; Pulsed xenon ultraviolet light.

MeSH terms

  • Biofilms / drug effects*
  • Cross Infection / prevention & control
  • Disinfection / methods*
  • Geobacillus stearothermophilus / drug effects
  • Humans
  • Klebsiella pneumoniae / drug effects
  • Laboratories, Hospital / standards*
  • Pseudomonas aeruginosa / drug effects
  • Staphylococcus aureus / drug effects
  • Ultraviolet Rays*
  • Xenon / administration & dosage*

Substances

  • Xenon