Antimicrobial efficacy of 405nm light against Clostridium difficile: evidence of enhanced sporicidal activity when combined with disinfectants

Sian Moorhead, Michelle MacLean, John Coia, John Anderson

Research output: Contribution to conferencePoster

Abstract

Clostridium difficile can cause major contamination problems due to its ability to form highly infectious and resilient spores which can survive in the environment for prolonged periods. Recent work has demonstrated the use of antimicrobial 405nm light for environmental decontamination within hospitals, however further information relating to efficacy against spores is required.
The aim of this investigation was to establish the efficacy of 405nm light for inactivation of C. difficile vegetative cells and spores, and to establish whether spore susceptibility can be enhanced by the combined use of 405nm light with low concentration chlorinated and non-chlorinated disinfectants.
C. difficile vegetative cells and spore suspensions were exposed to increasing doses of 405nm light (70-225mW/cm2) to establish sensitivity. Exposures were repeated with spores suspended in a range of routine hospital disinfectants at varying concentrations.
A 99.9% reduction in vegetative cell population was demonstrated with a dose of 252J/cm2, however spores demonstrated higher resilience, with a 10-fold increase in dose required. Enhanced sporicidal activity was achieved when spores were exposed in the presence of low concentration disinfectant
s, with 50% increase in susceptibility when exposed in the presence of 0.1% sodium hypochlorite.
C. difficile vegetative cells and spores can be successfully inactivated using 405nm light, and the sporicidal efficacy can be significantly enhanc
ed when exposed in the presence of low concentrations of disinfectants. Further research may lead to potential use of 405nm light decontamination in combination with hospital disinfectants to enhance C. difficile cleaning and
infection control procedures.

Conference

ConferenceThe 9th Healthcare Infection Society International Conference 2014
Abbreviated titleHIS2014
CountryFrance
CityLyon
Period16/11/1418/11/14
Internet address

Fingerprint

Disinfectants
Clostridium
Clostridium difficile
Spores
Light
Decontamination
Dosimetry
Sodium Hypochlorite
Cleaning
Contamination
Cells
Sodium
Suspensions

Keywords

  • Clostridium difficile
  • antimicrobial efficacy
  • spores
  • 405nm light
  • decontamination

Cite this

Moorhead, S., MacLean, M., Coia, J., & Anderson, J. (2014). Antimicrobial efficacy of 405nm light against Clostridium difficile: evidence of enhanced sporicidal activity when combined with disinfectants. Poster session presented at The 9th Healthcare Infection Society International Conference 2014, Lyon, France.
Moorhead, Sian ; MacLean, Michelle ; Coia, John ; Anderson, John. / Antimicrobial efficacy of 405nm light against Clostridium difficile : evidence of enhanced sporicidal activity when combined with disinfectants. Poster session presented at The 9th Healthcare Infection Society International Conference 2014, Lyon, France.
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abstract = "Clostridium difficile can cause major contamination problems due to its ability to form highly infectious and resilient spores which can survive in the environment for prolonged periods. Recent work has demonstrated the use of antimicrobial 405nm light for environmental decontamination within hospitals, however further information relating to efficacy against spores is required.The aim of this investigation was to establish the efficacy of 405nm light for inactivation of C. difficile vegetative cells and spores, and to establish whether spore susceptibility can be enhanced by the combined use of 405nm light with low concentration chlorinated and non-chlorinated disinfectants.C. difficile vegetative cells and spore suspensions were exposed to increasing doses of 405nm light (70-225mW/cm2) to establish sensitivity. Exposures were repeated with spores suspended in a range of routine hospital disinfectants at varying concentrations.A 99.9{\%} reduction in vegetative cell population was demonstrated with a dose of 252J/cm2, however spores demonstrated higher resilience, with a 10-fold increase in dose required. Enhanced sporicidal activity was achieved when spores were exposed in the presence of low concentration disinfectants, with 50{\%} increase in susceptibility when exposed in the presence of 0.1{\%} sodium hypochlorite.C. difficile vegetative cells and spores can be successfully inactivated using 405nm light, and the sporicidal efficacy can be significantly enhanced when exposed in the presence of low concentrations of disinfectants. Further research may lead to potential use of 405nm light decontamination in combination with hospital disinfectants to enhance C. difficile cleaning andinfection control procedures.",
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author = "Sian Moorhead and Michelle MacLean and John Coia and John Anderson",
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language = "English",
note = "The 9th Healthcare Infection Society International Conference 2014, HIS2014 ; Conference date: 16-11-2014 Through 18-11-2014",
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Moorhead, S, MacLean, M, Coia, J & Anderson, J 2014, 'Antimicrobial efficacy of 405nm light against Clostridium difficile: evidence of enhanced sporicidal activity when combined with disinfectants' The 9th Healthcare Infection Society International Conference 2014, Lyon, France, 16/11/14 - 18/11/14, .

Antimicrobial efficacy of 405nm light against Clostridium difficile : evidence of enhanced sporicidal activity when combined with disinfectants. / Moorhead, Sian; MacLean, Michelle; Coia, John; Anderson, John.

2014. Poster session presented at The 9th Healthcare Infection Society International Conference 2014, Lyon, France.

Research output: Contribution to conferencePoster

TY - CONF

T1 - Antimicrobial efficacy of 405nm light against Clostridium difficile

T2 - evidence of enhanced sporicidal activity when combined with disinfectants

AU - Moorhead, Sian

AU - MacLean, Michelle

AU - Coia, John

AU - Anderson, John

PY - 2014/11

Y1 - 2014/11

N2 - Clostridium difficile can cause major contamination problems due to its ability to form highly infectious and resilient spores which can survive in the environment for prolonged periods. Recent work has demonstrated the use of antimicrobial 405nm light for environmental decontamination within hospitals, however further information relating to efficacy against spores is required.The aim of this investigation was to establish the efficacy of 405nm light for inactivation of C. difficile vegetative cells and spores, and to establish whether spore susceptibility can be enhanced by the combined use of 405nm light with low concentration chlorinated and non-chlorinated disinfectants.C. difficile vegetative cells and spore suspensions were exposed to increasing doses of 405nm light (70-225mW/cm2) to establish sensitivity. Exposures were repeated with spores suspended in a range of routine hospital disinfectants at varying concentrations.A 99.9% reduction in vegetative cell population was demonstrated with a dose of 252J/cm2, however spores demonstrated higher resilience, with a 10-fold increase in dose required. Enhanced sporicidal activity was achieved when spores were exposed in the presence of low concentration disinfectants, with 50% increase in susceptibility when exposed in the presence of 0.1% sodium hypochlorite.C. difficile vegetative cells and spores can be successfully inactivated using 405nm light, and the sporicidal efficacy can be significantly enhanced when exposed in the presence of low concentrations of disinfectants. Further research may lead to potential use of 405nm light decontamination in combination with hospital disinfectants to enhance C. difficile cleaning andinfection control procedures.

AB - Clostridium difficile can cause major contamination problems due to its ability to form highly infectious and resilient spores which can survive in the environment for prolonged periods. Recent work has demonstrated the use of antimicrobial 405nm light for environmental decontamination within hospitals, however further information relating to efficacy against spores is required.The aim of this investigation was to establish the efficacy of 405nm light for inactivation of C. difficile vegetative cells and spores, and to establish whether spore susceptibility can be enhanced by the combined use of 405nm light with low concentration chlorinated and non-chlorinated disinfectants.C. difficile vegetative cells and spore suspensions were exposed to increasing doses of 405nm light (70-225mW/cm2) to establish sensitivity. Exposures were repeated with spores suspended in a range of routine hospital disinfectants at varying concentrations.A 99.9% reduction in vegetative cell population was demonstrated with a dose of 252J/cm2, however spores demonstrated higher resilience, with a 10-fold increase in dose required. Enhanced sporicidal activity was achieved when spores were exposed in the presence of low concentration disinfectants, with 50% increase in susceptibility when exposed in the presence of 0.1% sodium hypochlorite.C. difficile vegetative cells and spores can be successfully inactivated using 405nm light, and the sporicidal efficacy can be significantly enhanced when exposed in the presence of low concentrations of disinfectants. Further research may lead to potential use of 405nm light decontamination in combination with hospital disinfectants to enhance C. difficile cleaning andinfection control procedures.

KW - Clostridium difficile

KW - antimicrobial efficacy

KW - spores

KW - 405nm light

KW - decontamination

UR - http://www.his.org.uk/events/his2014

UR - http://www.his.org.uk/files/7414/1535/3959/Poster_abstracts_for_HIS_Website_Nov_2014.pdf

M3 - Poster

ER -

Moorhead S, MacLean M, Coia J, Anderson J. Antimicrobial efficacy of 405nm light against Clostridium difficile: evidence of enhanced sporicidal activity when combined with disinfectants. 2014. Poster session presented at The 9th Healthcare Infection Society International Conference 2014, Lyon, France.