Deactivation of SARS-CoV-2 with pulsed-xenon ultraviolet light: Implications for environmental COVID-19 control

Abstract

Objective Prolonged survival of SARS-CoV-2 on environmental surfaces and personal protective equipment may lead to these surfaces transmitting disease to others. This article reports the effectiveness of a pulsed xenon ultraviolet disinfection system in reducing the load of SARS-CoV-2 on hard surfaces and N95 respirators. Methods Chamber slides and N95 respirator material were directly inoculated with SARS-CoV-2 and exposed to different durations of pulsed xenon ultraviolet disinfection. Results For hard surfaces, disinfection for 1, 2, and 5 minutes resulted in 3·53 Log10, >4·54 Log10, and >4·12 Log10 reductions in viral load, respectively. For N95 respirators, disinfection for 5 minutes resulted in >4·79 Log10 reduction in viral load. We found that pulsed xenon ultraviolet significantly reduces SARS-CoV-2 on hard surfaces and N95 respirators. Conclusion With the potential to rapidly disinfectant environmental surfaces and N95 respirators, pulsed xenon ultraviolet devices are a promising technology for the reduction of environmental and personal protective equipment bioburden and to enhance both healthcare worker and patient safety by reducing the risk of exposure to SARS-CoV-2.

Effectiveness of 222-nm ultraviolet light on disinfecting SARS-CoV-2 surface contamination

“…3 The decrease of the viral titer of the control plate by dry conditions may have resulted in the plateau of the virus killing at a very low UV dose of 3 mJ/cm 2 . A few previous reports showed the effectiveness of UV disinfection on SARS-CoV-2 16,17 ; however, it is difficult to compare the result of this study to that of previous studies because the wavelength of UV or the experimental conditions are different. In contrast to the viable SARS-CoV-2, the copy number of SARS-CoV-2 RNA determined by RT-qPCR was not reduced even after 30 mJ/cm 2 (0.1 mW/cm 2 for 300 seconds) of 222-nm UVC irradiation.…”

“…[9][10][11][12][13] In addition, previous studies have reported that low dose of 222-nm UVC inactivated aerosolized H1N1 influenza virus and human coronaviruses alpha HCoV-229E and beta HCoV-OC43. 14,15 Although there are a few reports about the effectiveness of UV disinfection on SARS-CoV-2, 16,17 the effect of 222-nm UVC on SARS-CoV-2 is poorly understood. The aim of this study was to investigate the in vitro efficacy of 222-nm UV disinfection of SARS-CoV-2 contamination.…”

Investigating the Potential for Ultraviolet Light to Modulate Morbidity and Mortality From COVID-19: A Narrative Review and Update

“…UVC deactivates SARS-CoV-2 directly. Broad spectrum UVC (200–280 nm) substantially reduced SARS-CoV-2 titers on glass surfaces or N95 respirators by >4-log ( 85 ). UV radiation (~280 nm, 37.5 mJ/cm 2 ) rapidly inactivated >99% of SARS-CoV-2 virions within 10 s when delivered from a light-emitting diode ( 86 ).…”

SARS-CoV-2 in the environment—Non-droplet spreading routes

“…50,000 times the intensity of sunlight on the contact area, within a few seconds ( Rowan, 2019 ; Rowan and Laffey, 2020 ). Simmons et al (2020) demonstrated the effectiveness of PX-UV (Pulsed‑xenon-ultraviolet light) in the reduction of SARS-CoV -2 on the hard surface and of N95 respirators. The efficacy of UV depends on the dose, time exposure, distance, topography of the contaminated surface, and the location of microorganisms, and is affected by shading ( Rowan, 2019 ) ( Table 7 ).…”