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Takamure K, Iwatani Y, Amano H, Yagi T, Uchiyama T. Inactivation characteristics of a 280 nm Deep-UV irradiation dose on aerosolized SARS-CoV-2. ENVIRONMENT INTERNATIONAL 2023; 177:108022. [PMID: 37301046 PMCID: PMC10241504 DOI: 10.1016/j.envint.2023.108022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 06/03/2023] [Accepted: 06/03/2023] [Indexed: 06/12/2023]
Abstract
A non-filter virus inactivation unit was developed that can control the irradiation dose of aerosolized viruses by controlling the lighting pattern of a 280 nm deep-UV (DUV)-LED and the air flowrate. In this study, the inactivation properties of aerosolized SARS-CoV-2 were quantitatively evaluated by controlling the irradiation dose to the virus inside the inactivation unit. The RNA concentration of SARS-CoV-2 remained constant when the total irradiation dose of DUV irradiation to the virus exceeded 16.5 mJ/cm2. This observation suggests that RNA damage may occur in regions below the detection threshold of RT-qPCR assay. However, when the total irradiation dose was less than 16.5 mJ/cm2, the RNA concentration monotonically increased with a decreasing LED irradiation dose. However, the nucleocapsid protein concentration of SARS-CoV-2 was not predominantly dependent on the LED irradiation dose. The plaque assay showed that 99.16% of the virus was inactivated at 8.1 mJ/cm2 of irradiation, and no virus was detected at 12.2 mJ/cm2 of irradiation, resulting in a 99.89% virus inactivation rate. Thus, an irradiation dose of 23% of the maximal irradiation capacity of the virus inactivation unit can activate more than 99% of SARS-CoV-2. These findings are expected to enhance versatility in various applications. The downsizing achieved in our study renders the technology apt for installation in narrow spaces, while the enhanced flowrates establish its viability for implementation in larger facilities.
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Affiliation(s)
- Kotaro Takamure
- Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya 464-8601, Japan.
| | - Yasumasa Iwatani
- Clinical Research Center, National Hospital Organization Nagoya Medical Center, Nagoya 460-0001, Japan
| | - Hiroshi Amano
- Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya 464-8601, Japan
| | - Tetsuya Yagi
- Department of Infectious Diseases, Nagoya University Hospital, Nagoya 466-0065, Japan
| | - Tomomi Uchiyama
- Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya 464-8601, Japan
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2
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Azuma T, Katagiri M, Sasaki N, Kuroda M, Watanabe M. Performance of a Pilot-Scale Continuous Flow Ozone-Based Hospital Wastewater Treatment System. Antibiotics (Basel) 2023; 12:antibiotics12050932. [PMID: 37237835 DOI: 10.3390/antibiotics12050932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/16/2023] [Accepted: 05/17/2023] [Indexed: 05/28/2023] Open
Abstract
Antimicrobial resistance (AMR) is becoming a global concern. Recently, research has emerged to evaluate the human and environmental health implications of wastewater from medical facilities and to identify acceptable wastewater treatment methods. In this study, a disinfection wastewater treatment system using an ozone-based continuous flow system was installed in a general hospital located in Japan. The effectiveness of antimicrobial-resistant bacteria (ARB) and antimicrobials in mitigating the environmental impact of hospital wastewater was evaluated. Metagenomic analysis was conducted to characterize the microorganisms in the wastewater before and after treatment. The results demonstrated that ozone treatment enables effective inactivation of general gut bacteria, including Bacteroides, Prevotella, Escherichia coli, Klebsiella, DNA molecules, and ARGs, as well as antimicrobials. Azithromycin and doxycycline removal rates were >99% immediately after treatment, and levofloxacin and vancomycin removal rates remained between 90% and 97% for approximately one month. Clarithromycin was more readily removed than the other antimicrobials (81-91%), and no clear removal trend was observed for ampicillin. Our findings provide a better understanding of the environmental management of hospital wastewater and enhance the effectiveness of disinfection wastewater treatment systems at medical facilities for mitigating the discharge of pollutants into aquatic environments.
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Affiliation(s)
- Takashi Azuma
- Department of Pharmaceutical Sciences, Osaka Medical and Pharmaceutical University, Takatsuki 569-1094, Japan
| | - Miwa Katagiri
- Department of Surgery, Toho University Ohashi Medical Center, Tokyo 153-8515, Japan
| | - Naobumi Sasaki
- Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Makoto Kuroda
- Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Manabu Watanabe
- Department of Surgery, Toho University Ohashi Medical Center, Tokyo 153-8515, Japan
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3
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Enaki NA, Paslari T, Bazgan S, Starodub E, Munteanu I, Turcan M, Eremeev V, Profir A, Mihailescu IN. UVC radiation intensity dependence of pathogen decontamination rate: semiclassical theory and experiment. EUROPEAN PHYSICAL JOURNAL PLUS 2022; 137:1047. [PMID: 36123970 PMCID: PMC9476412 DOI: 10.1140/epjp/s13360-022-03252-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 09/01/2022] [Indexed: 06/15/2023]
Abstract
A semiclassical (light classical and molecule quantum) model describing the dependence of DNA/RNA dimerization rate as function of the ultraviolet C (UVC) radiation's intensity is proposed. Particularly, a nonlinear model is developed based on the Raman-like processes in quantum optics. The main result of the theory shows that the process of dimerization in the DNA/RNA depends strongly on the UVC light's intensity, thus proving a possible quantum microscopical mechanism of the interaction of UV light with the DNA. To corroborate the theoretical findings, we realize some experiments, by which want to investigate how the inactivation rate of the yeast colonies depends on the intensity of the UVC irradiation. The experimental results evidence a nonlinear decreasing of the residual yeast colonies as a function of the intensity in the irradiation process. The possibilities to optimize the intensity of UVC radiation in the considered decontamination equipment by using metamaterials are studied. The application of such equipment in disinfection of fluids (air, water, droplets, etc.), as well for the SARS-CoV-2-infected aerosols, is discussed.
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Affiliation(s)
- Nicolae A. Enaki
- Quantum Optics and Kinetic Processes Lab of Institute of Applied Physics of Moldova, Chisinau, MD 2028 Republic of Moldova
| | - Tatiana Paslari
- Quantum Optics and Kinetic Processes Lab of Institute of Applied Physics of Moldova, Chisinau, MD 2028 Republic of Moldova
| | - Sergiu Bazgan
- Quantum Optics and Kinetic Processes Lab of Institute of Applied Physics of Moldova, Chisinau, MD 2028 Republic of Moldova
| | - Elena Starodub
- Quantum Optics and Kinetic Processes Lab of Institute of Applied Physics of Moldova, Chisinau, MD 2028 Republic of Moldova
| | - Ion Munteanu
- Quantum Optics and Kinetic Processes Lab of Institute of Applied Physics of Moldova, Chisinau, MD 2028 Republic of Moldova
| | - Marina Turcan
- Quantum Optics and Kinetic Processes Lab of Institute of Applied Physics of Moldova, Chisinau, MD 2028 Republic of Moldova
| | - Vitalie Eremeev
- Quantum Optics and Kinetic Processes Lab of Institute of Applied Physics of Moldova, Chisinau, MD 2028 Republic of Moldova
- Instituto de Ciencias Básicas, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile
| | - Aurelia Profir
- Quantum Optics and Kinetic Processes Lab of Institute of Applied Physics of Moldova, Chisinau, MD 2028 Republic of Moldova
- Moldova State University Department of Computer Science, 60 Alexei Mateevici str., Chisinau, MD-2009 Republic of Moldova
| | - Ion N. Mihailescu
- National Institute for Lasers, Plasma and Radiation Physics, P.O. Box MG 36, 77125 Bucharest-Magurele, Romania
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Sayidmarie KH, Mohammed B, Mohammed AJ, Abbosh A. Combating Coronavirus Using Resonant Electromagnetic Irradiation. IEEE JOURNAL OF ELECTROMAGNETICS, RF AND MICROWAVES IN MEDICINE AND BIOLOGY 2022; 6:477-484. [PMID: 36514675 PMCID: PMC9728540 DOI: 10.1109/jerm.2022.3194727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 07/10/2022] [Accepted: 07/24/2022] [Indexed: 12/16/2022]
Abstract
The interaction of electromagnetic (EM) waves with the COVID-19 virus is studied to define the frequencies that cause maximum energy absorption by the virus and the power level needed to cause a lethal temperature rise. The full-wave EM simulator is used to model the virus and study the effects of its size and dielectric properties on the absorbed power across a wide range of frequencies. The results confirm potential resonance conditions, where specific frequencies produce maximum absorption and subsequent temperature rise that can destroy the virus. Furthermore, the study confirms that maximum power deposition in the virus occurs at specific wavelengths depending on its size. Also, the simulation is used to find the power required to destroy the virus and determine the total power required to destroy it in an oral activity, such as coughing, made by infected individuals. Furthermore, the study explained why irradiation by UV-C band is effective to decrease virus activity or even eradicate it.
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Affiliation(s)
| | - Beadaa Mohammed
- School of Information Technology and Electrical EngineeringThe University of Queensland Brisbane QLD 4103 Australia
| | - Asmaa J Mohammed
- College of Environmental Science and TechnologyMosul University Mosul 41001 Iraq
| | - Amin Abbosh
- School of Information Technology and Electrical EngineeringThe University of Queensland Brisbane QLD 4103 Australia
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5
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Weyersberg L, Klemens E, Buehler J, Vatter P, Hessling M. UVC, UVB and UVA susceptibility of Phi6 and its suitability as a SARS-CoV-2 surrogate. AIMS Microbiol 2022; 8:278-291. [PMID: 36317004 PMCID: PMC9576498 DOI: 10.3934/microbiol.2022020] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/07/2022] [Accepted: 07/03/2022] [Indexed: 11/19/2022] Open
Abstract
For SARS-CoV-2 disinfection systems or applications that are based on UVC, UVB or UVA irradiation, it would be desirable to have a SARS-CoV-2 surrogate for tests and development, which does not require a laboratory with a high biosafety level. The bacteriophage Phi 6, an enveloped RNA virus like coronaviruses, is an obvious candidate for such a surrogate. In this study, UVC, UVB and UVA log-reduction doses for Phi6 are determined by plaque assay. Log-reduction doses for SARS-CoV-2 are retrieved from a literature research. Because of a high variability of the published results, median log-reduction doses are determined for defined spectral ranges and compared to Phi6 data in the same intervals. The measured Phi6 log-reduction doses for UVC (254 nm), UVB (311 nm) and UVA (365 nm) are 31.7, 980 and 14 684 mJ/cm2, respectively. The determined median log-reduction doses for SARS-CoV-2 are much lower, only about 1.7 mJ/cm2 within the spectral interval 251-270 nm. Therefore, Phi6 can be photoinactivated by all UV wavelengths but it is much less UV sensitive compared to SARS-CoV-2 in all UV spectral ranges. Thus, Phi6 is no convincing SARS-CoV-2 surrogate in UV applications.
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Affiliation(s)
| | | | | | | | - Martin Hessling
- Ulm University of Applied Sciences, Department of Medical Engineering and Mechatronics, Albert Einstein-Allee 55, D-89081 Ulm, Germany
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Biasin M, Strizzi S, Bianco A, Macchi A, Utyro O, Pareschi G, Loffreda A, Cavalleri A, Lualdi M, Trabattoni D, Tacchetti C, Mazza D, Clerici M. UV and violet light can Neutralize SARS-CoV-2 Infectivity. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY 2022; 10:100107. [PMID: 35036965 PMCID: PMC8741330 DOI: 10.1016/j.jpap.2021.100107] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 12/31/2021] [Accepted: 12/31/2021] [Indexed: 12/15/2022] Open
Abstract
We performed an in-depth analysis of the virucidal effect of discrete wavelengths: UV-C (278 nm), UV-B (308 nm), UV-A (366 nm) and violet (405 nm) on SARS-CoV-2. By using a highly infectious titer of SARS-CoV-2 we observed that the violet light-dose resulting in a 2-log viral inactivation is only 104 times less efficient than UV-C light. Moreover, by qPCR (quantitative Polymerase chain reaction) and fluorescence in situ hybridization (FISH) approach we verified that the viral titer typically found in the sputum of COVID-19 patients can be completely inactivated by the long UV-wavelengths corresponding to UV-A and UV-B solar irradiation. The comparison of the UV action spectrum on SARS-CoV-2 to previous results obtained on other pathogens suggests that RNA viruses might be particularly sensitive to long UV wavelengths. Our data extend previous results showing that SARS-CoV-2 is highly susceptible to UV light and offer an explanation to the reduced incidence of SARS-CoV-2 infection seen in the summer season.
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Affiliation(s)
- Mara Biasin
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
| | - Sergio Strizzi
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
| | - Andrea Bianco
- Italian National Institute for Astrophysics (INAF) - Brera Astronomical Observatory, Merate, Italy
| | - Alberto Macchi
- Italian National Institute for Astrophysics (INAF) - Brera Astronomical Observatory, Merate, Italy
| | - Olga Utyro
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
| | - Giovanni Pareschi
- Italian National Institute for Astrophysics (INAF) - Brera Astronomical Observatory, Merate, Italy
| | - Alessia Loffreda
- Experimental Imaging Center, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Adalberto Cavalleri
- Epidemiology and Prevention Unit, IRCCS Foundation, Istituto Nazionale dei Tumori, Milan, Italy
| | - Manuela Lualdi
- Department of Imaging Diagnostic and Radioterapy, IRCCS Foundation, Istituto Nazionale dei Tumori, Milan, Italy
| | - Daria Trabattoni
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
| | - Carlo Tacchetti
- Experimental Imaging Center, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Davide Mazza
- Experimental Imaging Center, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Mario Clerici
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Don C. Gnocchi Foundation, IRCCS Foundation, Milan, Italy
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7
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Nambu T, Yano T, Umeda S, Yokoyama N, Honda H, Tanaka Y, Maegaki Y, Mori Y, Yoshimura M, Kobayashi S, Ichikawa S, Fujiwara Y, Ishii R, Kawakami Y, Uemukai M, Tanikawa T, Katayama R. DUV coherent light emission from ultracompact microcavity wavelength conversion device. OPTICS EXPRESS 2022; 30:18628-18637. [PMID: 36221660 DOI: 10.1364/oe.457538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 04/29/2022] [Indexed: 06/16/2023]
Abstract
A unique design of our ultracompact microcavity wavelength conversion device exploits the simple principle that the wavelength conversion efficiency is proportional to the square of the electric field amplitude of enhanced pump light in the microcavity, and expands the range of suitable device materials to include crystals that do not exhibit birefringence or ferroelectricity. Here, as a first step toward practical applications of all-solid-state ultracompact deep-ultraviolet coherent light sources, we adopted a low-birefringence paraelectric SrB4O7 crystal with great potential for wavelength conversion and high transparency down to 130 nm as our device material, and demonstrated 234 nm deep-ultraviolet coherent light generation, whose wavelength band is expected to be used for on-demand disinfection tools that can irradiate the human body.
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8
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Action Spectra of Bacteria and Purification of Pollutant Water at Faucets Using a Water Waveguide Method. WATER 2022. [DOI: 10.3390/w14091394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ultraviolet (UV) radiation treatment is an effective method for purifying pollutant water contaminated with bacteria and/or chemicals. As an emerging technology, purification by deep ultraviolet light-emitting diodes (DUV-LEDs) is promising. Few studies have used the point-source characteristics of LEDs and have instead replaced mercury vapor lamps with LEDs. Here, we show our recent progress in the instantaneous purification of contaminated water by combining the point-source characteristics of DUV-LEDs with a water waveguide (WW). Before the demonstration, we determined the efficacy of disinfection as a function of irradiation wavelength (action spectra) by constructing a wavelength tunable DUV light source. We found that, as a function of irradiation wavelength, there is a strong correlation between the dose-based inactivation rate constants and deoxyribonucleic acid (DNA) absorbance. Based on this correlation, the emission wavelength of 265 nm was determined as the most effective wavelength for disinfecting water contaminated with bacteria. Instantaneous 2-log disinfection levels of water contaminated with Escherichia coli O1 or Pseudomonas aeruginosa were demonstrated by using the DUV-LED WW method. We also discuss how far-UVC radiation shorter than 230 nm, which has recently been attracting attention and is known as a safe and effective disinfection wavelength for the human body, cannot give a higher-dose-based inactivation rate constant compared to that of 265 nm irradiation due to the larger absorption coefficient of water with a wavelength shorter than 230 nm.
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Mariita RM, Davis JH, Randive RV. Illuminating Human Norovirus: A Perspective on Disinfection of Water and Surfaces Using UVC, Norovirus Model Organisms, and Radiation Safety Considerations. Pathogens 2022; 11:226. [PMID: 35215169 PMCID: PMC8879714 DOI: 10.3390/pathogens11020226] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/22/2022] [Accepted: 02/03/2022] [Indexed: 02/04/2023] Open
Abstract
Human noroviruses (HuNoVs) are a major cause of gastroenteritis and are associated with high morbidity because of their ability to survive in the environment and small inoculum size required for infection. Norovirus is transmitted through water, food, high touch-surfaces, and human-to-human contact. Ultraviolet Subtype C (UVC) light-emitting diodes (LEDs) can disrupt the norovirus transmission chain for water, food, and surfaces. Here, we illuminate considerations to be adhered to when picking norovirus surrogates for disinfection studies and shine light on effective use of UVC for norovirus infection control in water and air and validation for such systems and explore the blind spot of radiation safety considerations when using UVC disinfection strategies. This perspective also discusses the promise of UVC for norovirus mitigation to save and ease life.
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Affiliation(s)
- Richard M. Mariita
- Crystal IS Inc., an Asahi Kasei Company, 70 Cohoes Avenue, Green Island, NY 12183, USA; (J.H.D.); (R.V.R.)
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10
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Vlaskin MS. Review of air disinfection approaches and proposal for thermal inactivation of airborne viruses as a life-style and an instrument to fight pandemics. APPLIED THERMAL ENGINEERING 2022; 202:117855. [PMID: 34867067 PMCID: PMC8628600 DOI: 10.1016/j.applthermaleng.2021.117855] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 10/20/2021] [Accepted: 11/24/2021] [Indexed: 05/02/2023]
Abstract
COVID-19 (Coronavirus Disease 2019) pandemic highlighted the importance of air biosecurity because SARS-CoV-2 is mainly transmitted from person to person via airborne droplets. Preventing infectious droplets from entering the body is one of the best ways to protect against infection. This paper reviews the transmission patterns of airborne pathogens and air disinfection methods. A particular emphasis is put on studies devoted to the thermal inactivation of viruses. These reviews reveal that air heat treatment has not been seriously considered as a possible air disinfection approach. Simple calculations show that the energy input required for thermal disinfection of human's air daily consumption is almost the same as for daily water consumption (by heat treatment from room temperature to 100 °C). Moreover, it is possible to organize a continuous heat recovery from the air already heated during disinfection to the inlet air, thus significantly increasing the energy efficiency. Therefore, I propose a solution for the thermal inactivation of airborne pathogens based on air heating and its subsequent cooling in a heat exchanger with heat recovery. Such a solution could be used to create mobile personal and stationary indoor air disinfectors, as well as heating, ventilation, and air conditioning systems. Thermal disinfection of air to breathe might one day be part of people's daily life like thermal disinfection of drinking water. Aside from limiting infectious disease transmission, thermal inactivation might be the basis for developing inhaled vaccines using thermally inactivated whole pathogens.
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Affiliation(s)
- Mikhail S Vlaskin
- Joint Institute for High Temperatures of the Russian Academy of Sciences, 13/2 Izhorskaya St, Moscow 125412, Russia
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Su WL, Lin CP, Huang HC, Wu YK, Yang MC, Chiu SK, Peng MY, Chan MC, Chao YC. Clinical Application of Ultraviolet C Inactivation of Severe Acute Respiratory Syndrome Coronavirus 2 in Contaminated Hospital Environments. Viruses 2021; 13:v13122367. [PMID: 34960637 PMCID: PMC8706350 DOI: 10.3390/v13122367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 11/18/2021] [Accepted: 11/22/2021] [Indexed: 01/25/2023] Open
Abstract
To overcome the ongoing coronavirus disease 2019 (COVID-19) pandemic, transmission routes, such as healthcare worker infection, must be effectively prevented. Ultraviolet C (UVC) (254 nm) has recently been demonstrated to prevent environmental contamination by infected patients; however, studies on its application in contaminated hospital settings are limited. Herein, we explored the clinical application of UVC and determined its optimal dose. Environmental samples (n = 267) collected in 2021 were analyzed by a reverse transcription-polymerase chain reaction and subjected to UVC irradiation for different durations (minutes). We found that washbasins had a high contamination rate (45.5%). SARS-CoV-2 was inactivated after 15 min (estimated dose: 126 mJ/cm2) of UVC irradiation, and the contamination decreased from 41.7% before irradiation to 16.7%, 8.3%, and 0% after 5, 10, and 15 min of irradiation, respectively (p = 0.005). However, SARS-CoV-2 was still detected in washbasins after irradiation for 20 min but not after 30 min (252 mJ/cm2). Thus, 15 min of 254-nm UVC irradiation was effective in cleaning plastic, steel, and wood surfaces in the isolation ward. For silicon items, such as washbasins, 30 min was suggested; however, further studies using hospital environmental samples are needed to confirm the effective UVC inactivation of SARS-CoV-2.
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Affiliation(s)
- Wen-Lin Su
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan; (Y.-K.W.); (M.-C.Y.)
- School of Medicine, Tzu Chi University, Hualien 970, Taiwan; (C.-P.L.); (S.-K.C.); (Y.-C.C.)
- Correspondence: ; Tel.: +886-2-6628-9779
| | - Chih-Pei Lin
- School of Medicine, Tzu Chi University, Hualien 970, Taiwan; (C.-P.L.); (S.-K.C.); (Y.-C.C.)
- Department of Pathology and Laboratory Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan;
| | - Hui-Ching Huang
- Department of Pathology and Laboratory Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan;
| | - Yao-Kuang Wu
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan; (Y.-K.W.); (M.-C.Y.)
- School of Medicine, Tzu Chi University, Hualien 970, Taiwan; (C.-P.L.); (S.-K.C.); (Y.-C.C.)
| | - Mei-Chen Yang
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan; (Y.-K.W.); (M.-C.Y.)
- School of Medicine, Tzu Chi University, Hualien 970, Taiwan; (C.-P.L.); (S.-K.C.); (Y.-C.C.)
| | - Sheg-Kang Chiu
- School of Medicine, Tzu Chi University, Hualien 970, Taiwan; (C.-P.L.); (S.-K.C.); (Y.-C.C.)
- Division of Infectious Disease, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan;
- Infection Control Center, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan;
| | - Ming-Yieh Peng
- Division of Infectious Disease, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan;
- Infection Control Center, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan;
| | - Ming-Chin Chan
- Infection Control Center, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan;
| | - You-Chen Chao
- School of Medicine, Tzu Chi University, Hualien 970, Taiwan; (C.-P.L.); (S.-K.C.); (Y.-C.C.)
- Division of Gastroenterology, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei 23142, Taiwan
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12
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High Intensity Violet Light (405 nm) Inactivates Coronaviruses in Phosphate Buffered Saline (PBS) and on Surfaces. PHOTONICS 2021. [DOI: 10.3390/photonics8100414] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
It has been proven that visible light with a wavelength of about 405 nm exhibits an antimicrobial effect on bacteria and fungi if the irradiation doses are high enough. Hence, the question arises as to whether this violet light would also be suitable to inactivate SARS-CoV-2 coronaviruses. Therefore, a high-intensity light source was developed and applied to irradiate bovine coronaviruses (BCoV), which are employed as SARS-CoV-2 surrogates for safety reasons. Irradiation is performed in virus solutions diluted with phosphate buffered saline and on steel surfaces. Significant virus reduction by several log levels was observed both in the liquid and on the surface within half an hour with average log reduction doses of 57.5 and 96 J/cm2, respectively. Therefore, it can be concluded that 405 nm irradiation has an antiviral effect on coronaviruses, but special attention should be paid to the presence of photosensitizers in the virus environment in future experiments. Technically, visible violet radiation is therefore suitable for coronavirus reduction, but the required radiation doses are difficult to achieve rapidly.
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