Universal decontamination of hospital surfaces in an occupied inpatient room with a continuous 405 nm light source

作者：Bache S E^*; Maclean M; Gettinby G; Anderson J G; MacGregor S J; Taggart I

来源：Journal of Hospital Infection, 2018, 98(1): 67-73.

DOI：10.1016/j.jhin.2017.07.010

• Infection control
• Environment
• Decontamination
• Bacterial contamination
• Burns unit
• 405 nm light

Background: Previous work has shown that a ceiling-mounted, 405 nm high-intensity narrow-spectrum light environmental decontamination system (HINS-light EDS) reduces bacterial contamination of environmental surfaces in a burns unit by between 27% and 75%. Examination of the efficacy of the light over extended exposure times and its probable mode of action was performed.
Aim: To ascertain the correlation between bacterial kill achieved on sampled surface sites around the burns unit and both irradiance levels of the 405 nm light, and exposure time.
Methods: Seventy samples were taken using contact agar plates from surfaces within an occupied side-room in the burns unit before, during, and after a seven-day use of the HIN Slight EDS. This was repeated in three separate studies. Statistical analysis determined whether there was significant decrease in environmental contamination during prolonged periods of HINS-light treatment, and whether there was an association between irradiance and bacterial kill.
Findings: A decrease of between 22% and 86% in the mean number of surface bacteria was shown during the use of the HINS-light EDS. When the light ceased to be used, increases of between 78% and 309% occurred. There was no correlation between bacterial kill and irradiance levels at each sampling site but strong correlation between bacterial kill and exposure time.
Conclusion: Prolonged exposure to the HINS-light EDS causes a cumulative decontamination of the surfaces within a burns unit. The importance of exposure time and possible airborne effect over irradiance levels is emphasized.

• 出版日期2018-1