Inactivation of Bacillus anthracis Spores on Surfaces with Ultraviolet Light Produced with a Low Pressure Mercury Lamp or Light Emitting Diodes
Citation:
Wood, Joe, J. Archer, Vipin Rastogi, AND S. Hurst. Inactivation of Bacillus anthracis Spores on Surfaces with Ultraviolet Light Produced with a Low Pressure Mercury Lamp or Light Emitting Diodes. Seminar for Korea BioDefense Research Institute, SeoulS, December 12, 2019.
Impact/Purpose:
.Methods and Results: Spores were deposited onto test coupons and controls of four different materials, via liquid suspension or aerosol deposition. The test coupons were then exposed to UVC light from either a low-pressure mercury vapor lamp or a system comprised of light emitting diodes, with a range of dosages. Positive controls were held at ambient conditions and not exposed to UVC light. Following exposure to UVC, spores were recovered from the coupons and efficacy was quantified in terms of log10 reduction (LR) in number of viable spores compared to that from positive controls. Conclusions: Decontamination efficacy varied by material and UVC dosage (efficacy up to 5.7 LR was demonstrated). There was no statistical difference in efficacy between the two species or between inoculation methods. Efficacy improved for the LED lamp at lower relative humidity, but this effect was not observed with the mercury vapor lamp. Significance and Impact of Study: This study will be useful in selection of UVC option for decontamination of B. anthracis spores on different surface types. These results will help in choosing appropriate exposure parameters for UVC inactivation of other spore-forming infectious disease agents.
Description:
This Presentation Aims: To obtain quantitative efficacy data of two ultraviolet light (UVC) technologies for surface inactivation of Bacillus anthracis Ames and Bacillus atrophaeus spores.