Katherine Ratliff, Michael Worth Calfee, Ahmed Abdel-Hady, Mariela Monge, Denise Aslett, Lukas Oudejans
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引用次数: 0
Abstract
Using technologies that emit ultraviolet-C (UVC) radiation to inactivate pathogens has gained increasing interest as a strategy for reducing the risk of disease transmission, but it can be difficult to predict their performance in applied settings. Directly irradiating occupied spaces with emerging far-UVC has been proposed, as its shorter wavelength (200-230 nm) is reportedly less damaging to human eyes and skin than longer wavelengths. In this study, we conducted surface tests to evaluate the impact of different inoculum compositions (with and without soil loads) and conditions (wet vs. dried droplets) to determine how these factors affect efficacy of UVC sources with peak emissions at 254 nm and 222 nm against five bacteria and two bacteriophages. The presence of a soil load reduced 222 nm UVC efficacy more than 254 nm, and both UVC sources were generally less effective against microbes in dried (vs. wet) inoculum. Given that pathogens will often be exposed to UVC in the presence of proteins, salts, and other constituents depending on how they are emitted, it is important to consider these challenges when quantifying efficacy.
期刊介绍:
Journal of & Letters in Applied Microbiology are two of the flagship research journals of the Society for Applied Microbiology (SfAM). For more than 75 years they have been publishing top quality research and reviews in the broad field of applied microbiology. The journals are provided to all SfAM members as well as having a global online readership totalling more than 500,000 downloads per year in more than 200 countries. Submitting authors can expect fast decision and publication times, averaging 33 days to first decision and 34 days from acceptance to online publication. There are no page charges.