1
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Ahmad Wadi AFA, Onomura D, Funamori H, Khatun MM, Okada S, Iizasa H, Yoshiyama H. Effects of Strain Differences, Humidity Changes, and Saliva Contamination on the Inactivation of SARS-CoV-2 by Ion Irradiation. Viruses 2024; 16:520. [PMID: 38675863 DOI: 10.3390/v16040520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 03/22/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
One of the methods to inactivate viruses is to denature viral proteins using released ions. However, there have been no reports detailing the effects of changes in humidity or contamination with body fluids on the inactivation of viruses. This study investigated the effects of humidity changes and saliva contamination on the efficacy of SARS-CoV-2 inactivation with ions using multiple viral strains. Virus solutions with different infectious titers were dropped onto a circular nitrocellulose membrane and irradiated with ions from 10 cm above the membrane. After the irradiation of ions for 60, 90, and 120 min, changes in viral infectious titers were measured. The effect of ions on virus inactivation under different humidity conditions was also examined using virus solutions containing 90% mixtures of saliva collected from 10 people. A decrease in viral infectivity was observed over time for all strains, but ion irradiation further accelerated the decrease in viral infectivity. Ion irradiation can inactivate all viral strains, but at 80% humidity, the effect did not appear until 90 min after irradiation. The presence of saliva protected the virus from drying and maintained infectiousness for a longer period compared with no saliva. In particular, the Omicron strain retained its infectivity titer longer than the other strains. Ion irradiation demonstrated a consistent reduction in the number of infectious viruses when compared to the control across varying levels of humidity and irradiation periods. This underscores the notable effectiveness of irradiation, even when the reduction effect is as modest as 50%, thereby emphasizing its crucial role in mitigating the rapid dissemination of SARS-CoV-2.
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Affiliation(s)
- Afifah Fatimah Azzahra Ahmad Wadi
- Department of Microbiology, Faculty of Medicine, Shimane University, 89-1 Enya, Izumo 693-8504, Shimane, Japan
- Faculty of Medicine, University of Muslim Indonesia, Makassar 9023, South Sulawesi, Indonesia
| | - Daichi Onomura
- Division of Virology, Department of Infection and Immunity, Faculty of Medicine, Jichi Medical University, Shimotsuke 329-0498, Tochigi, Japan
| | | | - Mst Mahmuda Khatun
- Department of Microbiology, Faculty of Medicine, Shimane University, 89-1 Enya, Izumo 693-8504, Shimane, Japan
| | - Shunpei Okada
- Department of Microbiology, Faculty of Medicine, Shimane University, 89-1 Enya, Izumo 693-8504, Shimane, Japan
| | - Hisashi Iizasa
- Department of Microbiology, Faculty of Medicine, Shimane University, 89-1 Enya, Izumo 693-8504, Shimane, Japan
| | - Hironori Yoshiyama
- Department of Microbiology, Faculty of Medicine, Shimane University, 89-1 Enya, Izumo 693-8504, Shimane, Japan
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2
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Parker JE, Rodriguez RA. Development of a charged model of the SARS-CoV-2 viral surface. Biochim Biophys Acta Biomembr 2023; 1865:184136. [PMID: 36746311 PMCID: PMC9898061 DOI: 10.1016/j.bbamem.2023.184136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 01/12/2023] [Accepted: 01/31/2023] [Indexed: 02/06/2023]
Abstract
A recent study provided experimental evidence of inactivation of viral activity after radio-frequency (RF) exposures in the 6-12 GHz band that was hypothesized to be caused by vibrations of an acoustic dipole mode in the virus that excited the viral membrane to failure. Here, we develop an atomic-scale molecular dynamics (MD) model of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral surface to estimate the electric fields necessary to rupture the viral membrane via dipole shaking of the virus. We computed the absorption spectrum of the system via unbiased MD simulations and found no particular strong absorption in the GHz band. We investigated the mechanical resiliency of the viral membrane by introducing uniaxial strains in the system and observed no pore formation in the membrane for strains up to 50%. Because the computed absorption spectrum was found to be essentially flat, and the strain required to break the viral membrane was >0.5, the field strength associated with rupture of the virus was greater than the dielectric breakdown value of air. Thus, RF disinfection of enveloped viruses would occur only once sufficient heat was transferred to the virus via a thermal mechanism and not by direct action (shaking) of the RF field oscillations on the viral membrane.
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Affiliation(s)
- James E Parker
- General Dynamics Information Technology, 4141 Petroleum Road, JBSA Fort Sam Houston, TX, 78234-2644, United States.
| | - Roberto A Rodriguez
- General Dynamics Information Technology, 4141 Petroleum Road, JBSA Fort Sam Houston, TX, 78234-2644, United States.
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3
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Kaya K, Khalil M, Fetrow B, Fritz H, Jagadesan P, Bondu V, Ista L, Chi EY, Schanze KS, Whitten DG, Kell A. Rapid and Effective Inactivation of SARS-CoV-2 with a Cationic Conjugated Oligomer with Visible Light: Studies of Antiviral Activity in Solutions and on Supports. ACS Appl Mater Interfaces 2022; 14:4892-4898. [PMID: 35040619 PMCID: PMC8790820 DOI: 10.1021/acsami.1c19716] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 12/30/2021] [Indexed: 05/12/2023]
Abstract
This paper presents results of a study of a new cationic oligomer that contains end groups and a chromophore affording inactivation of SARS-CoV-2 by visible light irradiation in solution or as a solid coating on paper wipes and glass fiber filtration substrates. A key finding of this study is that the cationic oligomer with a central thiophene ring and imidazolium charged groups gives outstanding performance in both the killing of E. coli bacterial cells and inactivation of the virus at very short times. Our introduction of cationic N-methyl imidazolium groups enhances the light activation process for both E. coli and SARS-CoV-2 but dampens the killing of the bacteria and eliminates the inactivation of the virus in the dark. For the studies with this oligomer in solution at a concentration of 1 μg/mL and E. coli, we obtain 3 log killing of the bacteria with 10 min of irradiation with LuzChem cool white lights (mimicking indoor illumination). With the oligomer in solution at a concentration of 10 μg/mL, we observe 4 log inactivation (99.99%) in 5 min of irradiation and total inactivation after 10 min. The oligomer is quite active against E. coli on oligomer-coated paper wipes and glass fiber filter supports. The SARS-CoV-2 is also inactivated by oligomer-coated glass fiber filter papers. This study indicates that these oligomer-coated materials may be very useful as wipes and filtration materials.
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Affiliation(s)
- Kemal Kaya
- Department
of Chemistry and Chemical Biology, University
of New Mexico, Albuquerque, New Mexico 87131-0001, United States
- Department
of Biochemistry, Kutahya Dumlupinar University, Kutahya 43000, Turkey
| | - Mohammed Khalil
- Center
for Biomedical Engineering and Department of Chemical and Biological
Engineering, University of New Mexico, Albuquerque, New Mexico 87131-0001, United States
| | - Benjamin Fetrow
- Center
for Biomedical Engineering and Department of Chemical and Biological
Engineering, University of New Mexico, Albuquerque, New Mexico 87131-0001, United States
| | - Hugh Fritz
- Department
of Chemistry and Chemical Biology, University
of New Mexico, Albuquerque, New Mexico 87131-0001, United States
| | - Pradeepkumar Jagadesan
- Department
of Chemistry, University of Texas at San
Antonio, San Antonio, Texas 78249-1644, United States
| | - Virginie Bondu
- Department
of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131-0001, United States
| | - Linnea Ista
- Center
for Biomedical Engineering and Department of Chemical and Biological
Engineering, University of New Mexico, Albuquerque, New Mexico 87131-0001, United States
| | - Eva Y. Chi
- Center
for Biomedical Engineering and Department of Chemical and Biological
Engineering, University of New Mexico, Albuquerque, New Mexico 87131-0001, United States
| | - Kirk S. Schanze
- Department
of Chemistry, University of Texas at San
Antonio, San Antonio, Texas 78249-1644, United States
| | - David G. Whitten
- Center
for Biomedical Engineering, Department of Chemistry and Chemical Biology,
and Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, New Mexico 87131-0001, United States
| | - Alison Kell
- Department
of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131-0001, United States
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4
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Lesho E, Newhart D, Reno L, Sleeper S, Nary J, Gutowski J, Yu S, Walsh E, Vargas R, Riedy D, Mayo R. Effectiveness of various cleaning strategies in acute and long-term care facilities during novel corona virus 2019 disease pandemic-related staff shortages. PLoS One 2022; 17:e0261365. [PMID: 35061676 PMCID: PMC8782535 DOI: 10.1371/journal.pone.0261365] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 11/30/2021] [Indexed: 01/22/2023] Open
Abstract
Background
Cleanliness of hospital surfaces helps prevent healthcare-associated infections, but comparative evaluations of various cleaning strategies during COVID-19 pandemic surges and worker shortages are scarce.
Purpose and methods
To evaluate the effectiveness of daily, enhanced terminal, and contingency-based cleaning strategies in an acute care hospital (ACH) and a long-term care facility (LTCF), using SARS-CoV-2 RT-PCR and adenosine triphosphate (ATP) assays. Daily cleaning involved light dusting and removal of visible debris while a patient is in the room. Enhanced terminal cleaning involved wet moping and surface wiping with disinfectants after a patient is permanently moved out of a room followed by ultraviolet light (UV-C), electrostatic spraying, or room fogging. Contingency-based strategies, performed only at the LTCF, involved cleaning by a commercial environmental remediation company with proprietary chemicals and room fogging. Ambient surface contamination was also assessed randomly, without regard to cleaning times. Near-patient or high-touch stationary and non-stationary environmental surfaces were sampled with pre-moistened swabs in viral transport media.
Results
At the ACH, SARS-CoV-2 RNA was detected on 66% of surfaces before cleaning and on 23% of those surfaces immediately after terminal cleaning, for a 65% post-cleaning reduction (p = 0.001). UV-C enhancement resulted in an 83% reduction (p = 0.023), while enhancement with electrostatic bleach application resulted in a 50% reduction (p = 0.010). ATP levels on RNA positive surfaces were not significantly different from those of RNA negative surfaces. LTCF contamination rates differed between the dementia, rehabilitation, and residential units (p = 0.005). 67% of surfaces had RNA after room fogging without terminal-style wiping. Fogging with wiping led to a -11% change in the proportion of positive surfaces. At the LTCF, mean ATP levels were lower after terminal cleaning (p = 0.016).
Conclusion
Ambient surface contamination varied by type of unit and outbreak conditions, but not facility type. Removal of SARS-CoV-2 RNA varied according to cleaning strategy.
Implications
Previous reports have shown time spent cleaning by hospital employed environmental services staff did not correlate with cleaning thoroughness. However, time spent cleaning by a commercial remediation company in this study was associated with cleaning effectiveness. These findings may be useful for optimizing allocation of cleaning resources during staffing shortages.
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Affiliation(s)
- Emil Lesho
- Rochester Regional Health, Rochester, NY, United States of America
- * E-mail:
| | - Donna Newhart
- Rochester Regional Health, Rochester, NY, United States of America
| | - Lisa Reno
- Rochester Regional Health, Rochester, NY, United States of America
| | - Scott Sleeper
- Rochester Regional Health, Rochester, NY, United States of America
| | - Julia Nary
- Rochester Regional Health, Rochester, NY, United States of America
| | | | - Stephanie Yu
- Rochester Regional Health, Rochester, NY, United States of America
| | - Edward Walsh
- University of Rochester School of Medicine and Dentistry, Rochester, NY, United States of America
| | - Roberto Vargas
- Rochester Regional Health, Rochester, NY, United States of America
| | - Dawn Riedy
- Rochester Regional Health, Rochester, NY, United States of America
| | - Robert Mayo
- Rochester Regional Health, Rochester, NY, United States of America
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5
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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6
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Lai PY, Liu H, Ng RJH, Wint Hnin Thet B, Chu HS, Teo JWR, Ong Q, Liu Y, Png CE. Investigation of SARS-CoV-2 inactivation using UV-C LEDs in public environments via ray-tracing simulation. Sci Rep 2021; 11:22612. [PMID: 34799671 PMCID: PMC8605003 DOI: 10.1038/s41598-021-02156-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 11/08/2021] [Indexed: 11/08/2022] Open
Abstract
This paper proposes an investigating SARS-CoV-2 inactivation on surfaces with UV-C LED irradiation using our in-house-developed ray-tracing simulator. The results are benchmarked with experiments and Zemax OpticStudio commercial software simulation to demonstrate our simulator's easy accessibility and high reliability. The tool can input the radiant profile of the flexible LED source and accurately yield the irradiance distribution emitted from an LED-based system in 3D environments. The UV-C operating space can be divided into the safe, buffer, and germicidal zones for setting up a UV-C LED system. Based on the published measurement data, the level of SARS-CoV-2 inactivation has been defined as a function of UV-C irradiation. A realistic case of public space, i.e., a food court in Singapore, has been numerically investigated to demonstrate the relative impact of environmental UV-C attenuation on the SARS-CoV-2 inactivation. We optimise a specific UV-C LED germicidal system and its corresponding exposure time according to the simulation results. These ray-tracing-based simulations provide a useful guideline for safe deployment and efficient design for germicidal UV-C LED technology.
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Affiliation(s)
- Po-Yen Lai
- A*STAR Institute of High Performance Computing, Electronics and Photonics, 1 Fusionopolis Way, #16-16, Connexis, 138632, Singapore.
| | - Huizhe Liu
- A*STAR Institute of High Performance Computing, Electronics and Photonics, 1 Fusionopolis Way, #16-16, Connexis, 138632, Singapore
| | - Ray Jia Hong Ng
- A*STAR Institute of High Performance Computing, Electronics and Photonics, 1 Fusionopolis Way, #16-16, Connexis, 138632, Singapore
| | - Bianca Wint Hnin Thet
- A*STAR Institute of High Performance Computing, Electronics and Photonics, 1 Fusionopolis Way, #16-16, Connexis, 138632, Singapore
| | - Hong-Son Chu
- A*STAR Institute of High Performance Computing, Electronics and Photonics, 1 Fusionopolis Way, #16-16, Connexis, 138632, Singapore
| | - Jin Wah Ronnie Teo
- A*STAR Singapore Institute of Manufacturing Technology, 2 Fusionopolis Way, #08-04, Innovis, 138634, Singapore
| | - Qunxiang Ong
- A*STAR Singapore Bioimaging Consortium, 11 Biopolis Way, #02-02, Helios, 138667, Singapore
| | - Yuanjie Liu
- A*STAR National Metrology Centre, 2 Fusionopolis Way, #08-05, Innovis, 138634, Singapore
| | - Ching Eng Png
- A*STAR Institute of High Performance Computing, Electronics and Photonics, 1 Fusionopolis Way, #16-16, Connexis, 138632, Singapore
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7
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Wondrak GT, Jandova J, Williams SJ, Schenten D. Solar simulated ultraviolet radiation inactivates HCoV-NL63 and SARS-CoV-2 coronaviruses at environmentally relevant doses. J Photochem Photobiol B 2021; 224:112319. [PMID: 34598020 PMCID: PMC8463283 DOI: 10.1016/j.jphotobiol.2021.112319] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 09/08/2021] [Accepted: 09/18/2021] [Indexed: 12/23/2022]
Abstract
The germicidal properties of short wavelength ultraviolet C (UVC) light are well established and used to inactivate many viruses and other microbes. However, much less is known about germicidal effects of terrestrial solar UV light, confined exclusively to wavelengths in the UVA and UVB regions. Here, we have explored the sensitivity of the human coronaviruses HCoV-NL63 and SARS-CoV-2 to solar-simulated full spectrum ultraviolet light (sUV) delivered at environmentally relevant doses. First, HCoV-NL63 coronavirus inactivation by sUV-exposure was confirmed employing (i) viral plaque assays, (ii) RT-qPCR detection of viral genome replication, and (iii) infection-induced stress response gene expression array analysis. Next, a detailed dose-response relationship of SARS-CoV-2 coronavirus inactivation by sUV was elucidated, suggesting a half maximal suppression of viral infectivity at low sUV doses. Likewise, extended sUV exposure of SARS-CoV-2 blocked cellular infection as revealed by plaque assay and stress response gene expression array analysis. Moreover, comparative (HCoV-NL63 versus SARS-CoV-2) single gene expression analysis by RT-qPCR confirmed that sUV exposure blocks coronavirus-induced redox, inflammatory, and proteotoxic stress responses. Based on our findings, we estimate that solar ground level full spectrum UV light impairs coronavirus infectivity at environmentally relevant doses. Given the urgency and global scale of the unfolding SARS-CoV-2 pandemic, these prototype data suggest feasibility of solar UV-induced viral inactivation, an observation deserving further molecular exploration in more relevant exposure models.
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Affiliation(s)
- Georg T Wondrak
- Department of Pharmacology and Toxicology, College of Pharmacy and UA Cancer Center, University of Arizona, Tucson, AZ, United States of America.
| | - Jana Jandova
- Department of Pharmacology and Toxicology, College of Pharmacy and UA Cancer Center, University of Arizona, Tucson, AZ, United States of America
| | - Spencer J Williams
- Department of Immunobiology, College of Medicine, University of Arizona, Tucson, AZ, United States of America
| | - Dominik Schenten
- Department of Immunobiology, College of Medicine, University of Arizona, Tucson, AZ, United States of America.
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8
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Boegel SJ, Gabriel M, Sasges M, Petri B, D’Agostino MR, Zhang A, Ang JC, Miller MS, Meunier SM, Aucoin MG. Robust Evaluation of Ultraviolet-C Sensitivity for SARS-CoV-2 and Surrogate Coronaviruses. Microbiol Spectr 2021; 9:e0053721. [PMID: 34668746 PMCID: PMC8528122 DOI: 10.1128/spectrum.00537-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 09/17/2021] [Indexed: 01/11/2023] Open
Abstract
UV light, more specifically UV-C light at a wavelength of 254 nm, is often used to disinfect surfaces, air, and liquids. In early 2020, at the cusp of the COVID-19 pandemic, UV light was identified as an efficient means of eliminating coronaviruses; however, the variability in published sensitivity data is evidence of the need for experimental rigor to accurately quantify the effectiveness of this technique. In the current study, reliable and reproducible UV techniques have been adopted, including accurate measurement of light intensity, consideration of fluid UV absorbance, and confirmation of uniform dose delivery, including dose verification using an established biological target (T1UV bacteriophage) and a resistant recombinant virus (baculovirus). The experimental results establish the UV sensitivity of SARS-CoV-2, HCoV-229E, HCoV-OC43, and mouse hepatitis virus (MHV) and highlight the potential for surrogate viruses for disinfection studies. All four coronaviruses were found to be easily inactivated by 254 nm irradiation, with UV sensitivities of 1.7, 1.8, 1.7, and 1.2 mJ/cm2/log10 reduction for SARS-CoV-2, HCoV-229E, HCoV-OC43, and MHV, respectively. Similar UV sensitivities for these species demonstrate the capacity for HCoV-OC43, HCoV-229E, and MHV to be considered surrogates for SARS-CoV-2 in UV-inactivation studies, greatly reducing hazards and simplifying procedures for future experimental studies. IMPORTANCE Disinfection of SARS-CoV-2 is of particular importance due to the global COVID-19 pandemic. UV-C irradiation is a compelling disinfection technique because it can be applied to surfaces, air, and water and is commonly used in drinking water and wastewater treatment facilities. UV inactivation depends on the dose received by an organism, regardless of the intensity of the light source or the optical properties of the medium in which it is suspended. The 254 nm irradiation sensitivity was accurately determined using benchmark methodology and a collimated beam apparatus for four coronaviruses (SARS-CoV-2, HCoV-229E, HCoV-OC43, and MHV), a surrogate indicator organism (T1UV), and a resistant recombinant virus (baculovirus vector). Considering the light distribution across the sample surface, the attenuation of light intensity with fluid depth, the optical absorbance of the fluid, and the sample uniformity due to mixing enable accurate measurement of the fundamental inactivation kinetics and UV sensitivity.
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Affiliation(s)
- S. J. Boegel
- Department of Chemical Engineering, University of Waterloo, Waterloo, Canada
| | | | | | - B. Petri
- Trojan Technologies, London, Canada
| | - M. R. D’Agostino
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster Immunology Research Centre, Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - A. Zhang
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster Immunology Research Centre, Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - J. C. Ang
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster Immunology Research Centre, Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - M. S. Miller
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster Immunology Research Centre, Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - S. M. Meunier
- Department of Chemical Engineering, University of Waterloo, Waterloo, Canada
| | - M. G. Aucoin
- Department of Chemical Engineering, University of Waterloo, Waterloo, Canada
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9
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Ma B, Gundy PM, Gerba CP, Sobsey MD, Linden KG. UV Inactivation of SARS-CoV-2 across the UVC Spectrum: KrCl* Excimer, Mercury-Vapor, and Light-Emitting-Diode (LED) Sources. Appl Environ Microbiol 2021; 87:e0153221. [PMID: 34495736 PMCID: PMC8552892 DOI: 10.1128/aem.01532-21] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 08/31/2021] [Indexed: 01/22/2023] Open
Abstract
Effective disinfection technology to combat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can help reduce viral transmission during the ongoing COVID-19 global pandemic and in the future. UV devices emitting UVC irradiation (200 to 280 nm) have proven to be effective for virus disinfection, but limited information is available for SARS-CoV-2 due to the safety requirements of testing, which is limited to biosafety level 3 (BSL3) laboratories. In this study, inactivation of SARS-CoV-2 in thin-film buffered aqueous solution (pH 7.4) was determined across UVC irradiation wavelengths of 222 to 282 nm from krypton chloride (KrCl*) excimers, a low-pressure mercury-vapor lamp, and two UVC light-emitting diodes. Our results show that all tested UVC devices can effectively inactivate SARS-CoV-2, among which the KrCl* excimer had the best disinfection performance (i.e., highest inactivation rate). The inactivation rate constants of SARS-CoV-2 across wavelengths are similar to those for murine hepatitis virus (MHV) from our previous investigation, suggesting that MHV can serve as a reliable surrogate of SARS-CoV-2 with a lower BSL requirement (BSL2) during UV disinfection tests. This study provides fundamental information on UVC's action on SARS-CoV-2 and guidance for achieving reliable disinfection performance with UVC devices. IMPORTANCE UV light is an effective tool to help stem the spread of respiratory viruses and protect public health in commercial, public, transportation, and health care settings. For effective use of UV, there is a need to determine the efficiency of different UV wavelengths in killing pathogens, specifically SARS-CoV-2, to support efforts to control the ongoing COVID-19 global pandemic and future coronavirus-caused respiratory virus pandemics. We found that SARS-CoV-2 can be inactivated effectively using a broad range of UVC wavelengths, and 222 nm provided the best disinfection performance. Interestingly, 222-nm irradiation has been found to be safe for human exposure up to thresholds that are beyond those effective for inactivating viruses. Therefore, applying UV light from KrCl* excimers in public spaces can effectively help reduce viral aerosol or surface-based transmissions.
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Affiliation(s)
- Ben Ma
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, Colorado, USA
| | - Patricia M. Gundy
- Department of Environmental Science, University of Arizona, Tucson, Arizona, USA
| | - Charles P. Gerba
- Department of Environmental Science, University of Arizona, Tucson, Arizona, USA
| | - Mark D. Sobsey
- Department of Environmental Science and Engineering, Gillings School of Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Karl G. Linden
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, Colorado, USA
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10
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Geldert A, Su A, Roberts AW, Golovkine G, Grist SM, Stanley SA, Herr AE. Mapping of UV-C dose and SARS-CoV-2 viral inactivation across N95 respirators during decontamination. Sci Rep 2021; 11:20341. [PMID: 34645859 PMCID: PMC8514565 DOI: 10.1038/s41598-021-98121-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/03/2021] [Indexed: 11/24/2022] Open
Abstract
During public health crises like the COVID-19 pandemic, ultraviolet-C (UV-C) decontamination of N95 respirators for emergency reuse has been implemented to mitigate shortages. Pathogen photoinactivation efficacy depends critically on UV-C dose, which is distance- and angle-dependent and thus varies substantially across N95 surfaces within a decontamination system. Due to nonuniform and system-dependent UV-C dose distributions, characterizing UV-C dose and resulting pathogen inactivation with sufficient spatial resolution on-N95 is key to designing and validating UV-C decontamination protocols. However, robust quantification of UV-C dose across N95 facepieces presents challenges, as few UV-C measurement tools have sufficient (1) small, flexible form factor, and (2) angular response. To address this gap, we combine optical modeling and quantitative photochromic indicator (PCI) dosimetry with viral inactivation assays to generate high-resolution maps of "on-N95" UV-C dose and concomitant SARS-CoV-2 viral inactivation across N95 facepieces within a commercial decontamination chamber. Using modeling to rapidly identify on-N95 locations of interest, in-situ measurements report a 17.4 ± 5.0-fold dose difference across N95 facepieces in the chamber, yielding 2.9 ± 0.2-log variation in SARS-CoV-2 inactivation. UV-C dose at several on-N95 locations was lower than the lowest-dose locations on the chamber floor, highlighting the importance of on-N95 dose validation. Overall, we integrate optical simulation with in-situ PCI dosimetry to relate UV-C dose and viral inactivation at specific on-N95 locations, establishing a versatile approach to characterize UV-C photoinactivation of pathogens contaminating complex substrates such as N95s.
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Affiliation(s)
- Alisha Geldert
- The UC Berkeley - UCSF Graduate Program in Bioengineering, University of California Berkeley, 308B Stanley Hall, Mailcode 1762, Berkeley, CA, 94720, USA
| | - Alison Su
- The UC Berkeley - UCSF Graduate Program in Bioengineering, University of California Berkeley, 308B Stanley Hall, Mailcode 1762, Berkeley, CA, 94720, USA
| | - Allison W Roberts
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Guillaume Golovkine
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Samantha M Grist
- Department of Bioengineering, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Sarah A Stanley
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, 94720, USA
- School of Public Health, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Amy E Herr
- The UC Berkeley - UCSF Graduate Program in Bioengineering, University of California Berkeley, 308B Stanley Hall, Mailcode 1762, Berkeley, CA, 94720, USA.
- Department of Bioengineering, University of California Berkeley, Berkeley, CA, 94720, USA.
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11
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Rathnasinghe R, Karlicek RF, Schotsaert M, Koffas M, Arduini BL, Jangra S, Wang B, Davis JL, Alnaggar M, Costa A, Vincent R, García-Sastre A, Vashishth D, Balchandani P. Scalable, effective, and rapid decontamination of SARS-CoV-2 contaminated N95 respirators using germicidal ultraviolet C (UVC) irradiation device. Sci Rep 2021; 11:19970. [PMID: 34620951 PMCID: PMC8497543 DOI: 10.1038/s41598-021-99431-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 09/16/2021] [Indexed: 01/17/2023] Open
Abstract
Particulate respirators such as N95s are an essential component of personal protective equipment (PPE) for front-line workers. This study describes a rapid and effective UVC irradiation system that would facilitate the safe re-use of N95 respirators and provides supporting information for deploying UVC for decontamination of SARS-CoV-2 during the COVID-19 pandemic. To assess the inactivation potential of the proposed UVC germicidal device as a function of time by using 3 M 8211-N95 particulate respirators inoculated with SARS-CoV-2. A germicidal UVC device to deliver tailored UVC dose was developed and test coupons (2.5 cm2) of the 3 M-N95 respirator were inoculated with 106 plaque-forming units (PFU) of SARS-CoV-2 and were UV irradiated. Different exposure times were tested (0-164 s) by fixing the distance between the lamp and the test coupon to 15.2 cm while providing an exposure of at least 5.43 mWcm-2. Primary measure of outcome was titration of infectious virus recovered from virus-inoculated respirator test coupons after UVC exposure. Other measures included the method validation of the irradiation protocol, using lentiviruses (biosafety level-2 agent) and establishment of the germicidal UVC exposure protocol. An average of 4.38 × 103 PFU ml-1 (SD 772.68) was recovered from untreated test coupons while 4.44 × 102 PFU ml-1 (SD 203.67), 4.00 × 102 PFU ml-1 (SD 115.47), 1.56 × 102 PFU ml-1 (SD 76.98) and 4.44 × 101 PFU ml-1 (SD 76.98) was recovered in exposures 2, 6, 18 and 54 s per side respectively. The germicidal device output and positioning was monitored and a minimum output of 5.43 mW cm-2 was maintained. Infectious SARS-CoV-2 was not detected by plaque assays (minimal level of detection is 67 PFU ml-1) on N95 respirator test coupons when irradiated for 120 s per side or longer suggesting 3.5 log reduction in 240 s of irradiation, 1.3 J cm-2. A scalable germicidal UVC device to deliver tailored UVC dose for rapid decontamination of SARS-CoV-2 was developed. UVC germicidal irradiation of N95 test coupons inoculated with SARS-CoV-2 for 120 s per side resulted in 3.5 log reduction of virus. These data support the reuse of N95 particle-filtrate apparatus upon irradiation with UVC and supports use of UVC-based decontamination of SARS-CoV-2 during the COVID-19 pandemic.
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Affiliation(s)
- Raveen Rathnasinghe
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Robert F Karlicek
- Smart Lighting Engineering Research Center, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
- Department of Electrical Computer and Systems Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Michael Schotsaert
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Mattheos Koffas
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Brigitte L Arduini
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Sonia Jangra
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Bowen Wang
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Jason L Davis
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Mohammed Alnaggar
- Department of Civil and Environmental Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Anthony Costa
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Richard Vincent
- Department of Medicine, Section of General Internal Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Adolfo García-Sastre
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Department of Medicine, Division of Infectious Diseases, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Deepak Vashishth
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA.
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA.
| | - Priti Balchandani
- BioMedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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12
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Cotman ZJ, Bowden MJ, Richter BP, Phelps JH, Dibble CJ. Factors affecting aerosol SARS-CoV-2 transmission via HVAC systems; a modeling study. PLoS Comput Biol 2021; 17:e1009474. [PMID: 34662342 PMCID: PMC8553169 DOI: 10.1371/journal.pcbi.1009474] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 10/28/2021] [Accepted: 09/23/2021] [Indexed: 12/11/2022] Open
Abstract
The role of heating, ventilation, and air-conditioning (HVAC) systems in the transmission of SARS-CoV-2 is unclear. To address this gap, we simulated the release of SARS-CoV-2 in a multistory office building and three social gathering settings (bar/restaurant, nightclub, wedding venue) using a well-mixed, multi-zone building model similar to those used by Wells, Riley, and others. We varied key factors of HVAC systems, such as the Air Changes Per Hour rate (ACH), Fraction of Outside Air (FOA), and Minimum Efficiency Reporting Values (MERV) to examine their effect on viral transmission, and additionally simulated the protective effects of in-unit ultraviolet light decontamination (UVC) and separate in-room air filtration. In all building types, increasing the ACH reduced simulated infections, and the effects were seen even with low aerosol emission rates. However, the benefits of increasing the fraction of outside air and filter efficiency rating were greatest when the aerosol emission rate was high. UVC filtration improved the performance of typical HVAC systems. In-room filtration in an office setting similarly reduced overall infections but worked better when placed in every room. Overall, we found little evidence that HVAC systems facilitate SARS-CoV-2 transmission; most infections in the simulated office occurred near the emission source, with some infections in individuals temporarily visiting the release zone. HVAC systems only increased infections in one scenario involving a marginal increase in airflow in a poorly ventilated space, which slightly increased the likelihood of transmission outside the release zone. We found that improving air circulation rates, increasing filter MERV rating, increasing the fraction of outside air, and applying UVC radiation and in-room filtration may reduce SARS-CoV-2 transmission indoors. However, these mitigation measures are unlikely to provide a protective benefit unless SARS-CoV-2 aerosol emission rates are high (>1,000 Plaque-forming units (PFU) / min).
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Affiliation(s)
- Zachary J. Cotman
- Battelle Memorial Institute, Columbus, Ohio, United States of America
| | - Michael J. Bowden
- Battelle Memorial Institute, Columbus, Ohio, United States of America
| | | | - Joseph H. Phelps
- Battelle Memorial Institute, Columbus, Ohio, United States of America
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13
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Abstract
This review examines the beneficial effects of ultraviolet radiation on systemic autoimmune diseases, including multiple sclerosis and type I diabetes, where the epidemiological evidence for the vitamin D-independent effects of sunlight is most apparent. Ultraviolet radiation, in addition to its role in the synthesis of vitamin D, stimulates anti-inflammatory pathways, alters the composition of dendritic cells, T cells, and T regulatory cells, and induces nitric oxide synthase and heme oxygenase metabolic pathways, which may directly or indirectly mitigate disease progression and susceptibility. Recent work has also explored how the immune-modulating functions of ultraviolet radiation affect type II diabetes, cancer, and the current global pandemic caused by SARS-CoV-2. These diseases are particularly important amidst global changes in lifestyle that result in unhealthy eating, increased sedentary habits, and alcohol and tobacco consumption. Compelling epidemiological data shows increased ultraviolet radiation associated with reduced rates of certain cancers, such as colorectal cancer, breast cancer, non-Hodgkins lymphoma, and ultraviolet radiation exposure correlated with susceptibility and mortality rates of COVID-19. Therefore, understanding the effects of ultraviolet radiation on both vitamin D-dependent and -independent pathways is necessary to understand how they influence the course of many human diseases.
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Affiliation(s)
- Anna S Erem
- Department of Pathology, Emory University School of Medicine, Atlanta, GA, USA
| | - Mohammed S Razzaque
- Department of Pathology, Lake Erie College of Osteopathic Medicine, Erie, PA, USA.
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14
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Rathnasinghe R, Jangra S, Miorin L, Schotsaert M, Yahnke C, Garcίa-Sastre A. The virucidal effects of 405 nm visible light on SARS-CoV-2 and influenza A virus. Sci Rep 2021; 11:19470. [PMID: 34593848 PMCID: PMC8484654 DOI: 10.1038/s41598-021-97797-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 08/26/2021] [Indexed: 12/23/2022] Open
Abstract
The germicidal potential of specific wavelengths within the electromagnetic spectrum is an area of growing interest. While ultra-violet (UV) based technologies have shown satisfactory virucidal potential, the photo-toxicity in humans coupled with UV associated polymer degradation limit their use in occupied spaces. Alternatively, longer wavelengths with less irradiation energy such as visible light (405 nm) have largely been explored in the context of bactericidal and fungicidal applications. Such studies indicated that 405 nm mediated inactivation is caused by the absorbance of porphyrins within the organism creating reactive oxygen species which result in free radical damage to its DNA and disruption of cellular functions. The virucidal potential of visible-light based technologies has been largely unexplored and speculated to be ineffective given the lack of porphyrins in viruses. The current study demonstrated increased susceptibility of lipid-enveloped respiratory pathogens of importance such as SARS-CoV-2 (causative agent of COVID-19) and influenza A virus to 405 nm, visible light in the absence of exogenous photosensitizers thereby indicating a potential alternative porphyrin-independent mechanism of visible light mediated viral inactivation. These results were obtained using less than expected irradiance levels which are considered safe for humans and commercially achievable. Our results support further exploration of the use of visible light technology for the application of continuous decontamination in occupied areas within hospitals and/or infectious disease laboratories, specifically for the inactivation of respiratory pathogens such as SARS-CoV-2 and Influenza A.
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Affiliation(s)
- Raveen Rathnasinghe
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Sonia Jangra
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Lisa Miorin
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Michael Schotsaert
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | | | - Adolfo Garcίa-Sastre
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- Division of Infectious Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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15
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Cuthbert TJ, Ennis S, Musolino SF, Buckley HL, Niikura M, Wulff JE, Menon C. Covalent functionalization of polypropylene filters with diazirine-photosensitizer conjugates producing visible light driven virus inactivating materials. Sci Rep 2021; 11:19029. [PMID: 34561486 PMCID: PMC8463589 DOI: 10.1038/s41598-021-98280-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 08/25/2021] [Indexed: 11/17/2022] Open
Abstract
The SARS-CoV-2 pandemic has highlighted the weaknesses of relying on single-use mask and respirator personal protective equipment (PPE) and the global supply chain that supports this market. There have been no major innovations in filter technology for PPE in the past two decades. Non-woven textiles used for filtering PPE are single-use products in the healthcare environment; use and protection is focused on preventing infection from airborne or aerosolized pathogens such as Influenza A virus or SARS-CoV-2. Recently, C-H bond activation under mild and controllable conditions was reported for crosslinking commodity aliphatic polymers such as polyethylene and polypropylene. Significantly, these are the same types of polymers used in PPE filtration systems. In this report, we take advantage of this C-H insertion method to covalently attach a photosensitizing zinc-porphyrin to the surface of a melt-blow non-woven textile filter material. With the photosensitizer covalently attached to the surface of the textile, illumination with visible light was expected to produce oxidizing 1O2/ROS at the surface of the material that would result in pathogen inactivation. The filter was tested for its ability to inactivate Influenza A virus, an enveloped RNA virus similar to SARS-CoV-2, over a period of four hours with illumination of high intensity visible light. The photosensitizer-functionalized polypropylene filter inactivated our model virus by 99.99% in comparison to a control.
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Affiliation(s)
- T J Cuthbert
- Department of Health Sciences and Technology, ETH Zürich, 8008, Zürich, Switzerland.
- Schools of Mechatronic Systems Engineering and Engineering Science, Simon Fraser University, Metro Vancouver, BC, V5A 1S6, Canada.
| | - S Ennis
- Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
| | - S F Musolino
- Department of Chemistry, University of Victoria, Victoria, BC, V8W 3V6, Canada
| | - H L Buckley
- Department of Civil Engineering, University of Victoria, Victoria, BC, V8W 3V6, Canada
| | - M Niikura
- Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
| | - J E Wulff
- Department of Chemistry, University of Victoria, Victoria, BC, V8W 3V6, Canada
| | - C Menon
- Department of Health Sciences and Technology, ETH Zürich, 8008, Zürich, Switzerland
- Schools of Mechatronic Systems Engineering and Engineering Science, Simon Fraser University, Metro Vancouver, BC, V5A 1S6, Canada
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16
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Crawford MJ, Ramezani S, Jabbari R, Pathak P, Cho HJ, Kim BN, Choi H. Development of a novel self-sanitizing mask prototype to combat the spread of infectious disease and reduce unnecessary waste. Sci Rep 2021; 11:18213. [PMID: 34521866 PMCID: PMC8440541 DOI: 10.1038/s41598-021-97357-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 08/23/2021] [Indexed: 12/04/2022] Open
Abstract
With the spread of COVID-19, significant emphasis has been placed on mitigation techniques such as mask wearing to slow infectious disease transmission. Widespread use of face coverings has revealed challenges such as mask contamination and waste, presenting an opportunity to improve the current technologies. In response, we have developed the Auto-sanitizing Retractable Mask Optimized for Reusability (ARMOR). ARMOR is a novel, reusable face covering that can be quickly disinfected using an array of ultraviolet C lamps contained within a wearable case. A nanomembrane UVC sensor was used to quantify the intensity of germicidal radiation at 18 different locations on the face covering and determine the necessary exposure time to inactivate SARS-CoV-2 in addition to other viruses and bacteria. After experimentation, it was found that ARMOR successfully provided germicidal radiation to all areas of the mask and will inactivate SARS-CoV-2 in approximately 180 s, H1N1 Influenza in 130 s, and Mycobacterium tuberculosis in 113 s, proving that this design is effective at eliminating a variety of pathogens and can serve as an alternative to traditional waste-producing disposable face masks. The accessibility, ease of use, and speed of sanitization supports the wide application of ARMOR in both clinical and public settings.
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Affiliation(s)
- Matthew J Crawford
- Department of Biomedical Sciences, University of Central Florida, Orlando, 32816, USA
| | - Sepehr Ramezani
- Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, 32816, USA
| | | | - Pawan Pathak
- Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, 32816, USA
| | - Hyoung J Cho
- Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, 32816, USA
| | - Brian N Kim
- Department of Electrical and Computer Engineering, University of Central Florida, Orlando, 32816, USA
| | - Hwan Choi
- Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, 32816, USA.
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17
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Raiteux J, Eschlimann M, Marangon A, Rogée S, Dadvisard M, Taysse L, Larigauderie G. Inactivation of SARS-CoV-2 by Simulated Sunlight on Contaminated Surfaces. Microbiol Spectr 2021; 9:e0033321. [PMID: 34287031 PMCID: PMC8552605 DOI: 10.1128/spectrum.00333-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 06/30/2021] [Indexed: 12/21/2022] Open
Abstract
We studied the stability of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) under different simulated outdoor conditions by changing the temperature (20°C and 35°C), the illuminance (darkness, 10 klx, and 56 klx), and/or the cleanness of the surfaces at 50% relative humidity (RH). In darkness, the loss of viability of the virus on stainless steel is temperature dependent, but this is hidden by the effect of the sunlight from the first minutes of exposure. The virus shows a sensitivity to sunlight proportional to the illuminance intensity of the sunlight. The presence of interfering substances has a moderate effect on virus viability even with an elevated illuminance. Thus, SARS-CoV-2 is rapidly inactivated by simulated sunlight in the presence or absence of high levels of interfering substances at 20°C or 35°C and 50% relative humidity. IMPORTANCE Clinical matrix contains high levels of interfering substances. This study is the first to reveal that the presence of high levels of interfering substances had little impact on the persistence of SARS-CoV-2 on stainless steel following exposure to simulated sunlight. Thus, SARS-CoV-2 should be rapidly inactivated in outdoor environments in the presence or absence of interfering substances. Our results indicate that transmission of SARS-CoV-2 is unlikely to occur through outdoor surfaces, dependent on illuminance intensity. Moreover, most studies are interested in lineage S of SARS-CoV-2. In our experiments, we studied the stability of L-type strains, which comprise the majority of strains isolated from worldwide patients. Nevertheless, the effect of sunlight seems to be similar regardless of the strain studied, suggesting that the greater spread of certain variants is not correlated with better survival in outdoor conditions.
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18
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Djellabi R, Basilico N, Delbue S, D’Alessandro S, Parapini S, Cerrato G, Laurenti E, Falletta E, Bianchi CL. Oxidative Inactivation of SARS-CoV-2 on Photoactive AgNPs@TiO 2 Ceramic Tiles. Int J Mol Sci 2021; 22:ijms22168836. [PMID: 34445543 PMCID: PMC8396237 DOI: 10.3390/ijms22168836] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 08/13/2021] [Accepted: 08/15/2021] [Indexed: 12/29/2022] Open
Abstract
The current SARS-CoV-2 pandemic causes serious public health, social, and economic issues all over the globe. Surface transmission has been claimed as a possible SARS-CoV-2 infection route, especially in heavy contaminated environmental surfaces, including hospitals and crowded public places. Herein, we studied the deactivation of SARS-CoV-2 on photoactive AgNPs@TiO2 coated on industrial ceramic tiles under dark, UVA, and LED light irradiations. SARS-CoV-2 inactivation is effective under any light/dark conditions. The presence of AgNPs has an important key to limit the survival of SARS-CoV-2 in the dark; moreover, there is a synergistic action when TiO2 is decorated with Ag to enhance the virus photocatalytic inactivation even under LED. The radical oxidation was confirmed as the the central mechanism behind SARS-CoV-2 damage/inactivation by ESR analysis under LED light. Therefore, photoactive AgNPs@TiO2 ceramic tiles could be exploited to fight surface infections, especially during viral severe pandemics.
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Affiliation(s)
- Ridha Djellabi
- Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milan, Italy;
- Correspondence: (R.D.); (C.L.B.)
| | - Nicoletta Basilico
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Via Carlo Pascal 36, 20133 Milan, Italy; (N.B.); (S.D.)
| | - Serena Delbue
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Via Carlo Pascal 36, 20133 Milan, Italy; (N.B.); (S.D.)
| | - Sarah D’Alessandro
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Carlo Pascal 36, 20133 Milan, Italy;
| | - Silvia Parapini
- Department of Biomedical Sciences for Health, University of Milan, Via Carlo Pascal 36, 20133 Milan, Italy;
| | - Giuseppina Cerrato
- Department of Chemistry, University of Turin, Via Pietro Giuria 7, 10125 Turin, Italy; (G.C.); (E.L.)
| | - Enzo Laurenti
- Department of Chemistry, University of Turin, Via Pietro Giuria 7, 10125 Turin, Italy; (G.C.); (E.L.)
| | - Ermelinda Falletta
- Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milan, Italy;
| | - Claudia Letizia Bianchi
- Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milan, Italy;
- Correspondence: (R.D.); (C.L.B.)
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19
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Hill SC, Mackowski DW, Doughty DC. Shielding of viruses such as SARS-Cov-2 from ultraviolet radiation in particles generated by sneezing or coughing: Numerical simulations of survival fractions. J Occup Environ Hyg 2021; 18:394-408. [PMID: 34161194 DOI: 10.1080/15459624.2021.1939877] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
SARS-CoV-2 and other microbes within aerosol particles can be partially shielded from UV radiation. The particles refract and absorb light, and thereby reduce the UV intensity at various locations within the particle. Previously, we demonstrated shielding in calculations of UV intensities within spherical approximations of SARS-CoV-2 virions within spherical particles approximating dried-to-equilibrium respiratory fluids. The purpose of this paper is to extend that work to survival fractions of virions (i.e., fractions of virions that can infect cells) within spherical particles approximating dried respiratory fluids, and to investigate the implications of these calculations for using UV light for disinfection. The particles may be on a surface or in air. Here, the survival fraction (S) of a set of individual virions illuminated with a UV fluence (F, in J/m2) is assumed described by S(kF) = exp(-kF), where k is the UV inactivation rate constant (m2/J). The average survival fraction (Sp) of the simulated virions in a group of particles is calculated using the energy absorbed by each virion in the particles. The results show that virions within particles of dried respiratory fluids can have larger Sp than do individual virions. For individual virions, and virions within 1-, 5-, and 9-µm particles illuminated (normal incidence) on a surface with 260-nm UV light, the Sp = 0.00005, 0.0155, 0.22, and 0.28, respectively, when kF = 10. The Sp decrease to <10-7, <10-7, 0.077, and 0.15, respectively, for kF = 100. Results also show that illuminating particles with UV beams from widely separated directions can strongly reduce the Sp. These results suggest that the size distributions and optical properties of the dried particles of virion-containing respiratory fluids are likely important to effectively designing and using UV germicidal irradiation systems for microbes in particles. The results suggest the use of reflective surfaces to increase the angles of illumination and decrease the Sp. The results suggest the need for measurements of the Sp of SARS-CoV-2 in particles having compositions and sizes relevant to the modes of disease transmission.
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20
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Martínez-Antón JC, Brun A, Vázquez D, Moreno S, Fernández-Balbuena AA, Alda J. Determination of the characteristic inactivation fluence for SARS-CoV-2 under UV-C radiation considering light absorption in culture media. Sci Rep 2021; 11:15293. [PMID: 34315976 PMCID: PMC8316444 DOI: 10.1038/s41598-021-94648-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 07/14/2021] [Indexed: 01/21/2023] Open
Abstract
The optical absorption coefficient of culture media is critical for the survival analysis of pathogens under optical irradiation. The quality of the results obtained from experiments relies on the optical analysis of the spatial distribution of fluence which also depends on the geometry of the sample. In this contribution, we consider both the geometrical shape and the culture medium's absorption coefficient to evaluate how the spatial distribution of optical radiation affects pathogens/viruses. In this work, we exposed SARS-CoV-2 to UV-C radiation ([Formula: see text] = 254 nm) and we calculated-considering the influence of the optical absorption of the culture medium-a characteristic inactivation fluence of [Formula: see text] = 4.7 J/m2, or an equivalent 10% survival (D90 dose) of 10.8 J/m2. Experimentally, we diluted the virus into sessile drops of Dulbecco's Modified Eagle Medium to evaluate pathogen activity after controlled doses of UV irradiation. To validate the optical absorption mode, we carried out an additional experiment where we varied droplet size. Our model-including optical absorption and geometrical considerations-provides robust results among a variety of experimental situations, and represents our experimental conditions more accurately. These results will help to evaluate the capability of UV disinfecting strategies applied to a variety of everyday situations, including the case of micro-droplets generated by respiratory functions.
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Affiliation(s)
- Juan Carlos Martínez-Antón
- Applied Optics Complutense Group, Faculty of Optics and Optometry, University Complutense of Madrid, Av. Arcos de Jalón, 118, 28037, Madrid, Spain
| | - Alejandro Brun
- Centro de Investigación en Sanidad Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Carretera Algete-El Casar de Talamanca, Km 8.1, 28130, Valdeolmos, Madrid, Spain
| | - Daniel Vázquez
- Applied Optics Complutense Group, Faculty of Optics and Optometry, University Complutense of Madrid, Av. Arcos de Jalón, 118, 28037, Madrid, Spain
| | - Sandra Moreno
- Centro de Investigación en Sanidad Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Carretera Algete-El Casar de Talamanca, Km 8.1, 28130, Valdeolmos, Madrid, Spain
| | - Antonio A Fernández-Balbuena
- Applied Optics Complutense Group, Faculty of Optics and Optometry, University Complutense of Madrid, Av. Arcos de Jalón, 118, 28037, Madrid, Spain
| | - Javier Alda
- Applied Optics Complutense Group, Faculty of Optics and Optometry, University Complutense of Madrid, Av. Arcos de Jalón, 118, 28037, Madrid, Spain.
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21
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Weaver DT, McElvany BD, Gopalakrishnan V, Card KJ, Crozier D, Dhawan A, Dinh MN, Dolson E, Farrokhian N, Hitomi M, Ho E, Jagdish T, King ES, Cadnum JL, Donskey CJ, Krishnan N, Kuzmin G, Li J, Maltas J, Mo J, Pelesko J, Scarborough JA, Sedor G, Tian E, An GC, Diehl SA, Scott JG. UV decontamination of personal protective equipment with idle laboratory biosafety cabinets during the COVID-19 pandemic. PLoS One 2021; 16:e0241734. [PMID: 34310599 PMCID: PMC8312969 DOI: 10.1371/journal.pone.0241734] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 06/19/2021] [Indexed: 11/22/2022] Open
Abstract
Personal protective equipment (PPE) is crucially important to the safety of both patients and medical personnel, particularly in the event of an infectious pandemic. As the incidence of Coronavirus Disease 2019 (COVID-19) increases exponentially in the United States and many parts of the world, healthcare provider demand for these necessities is currently outpacing supply. In the midst of the current pandemic, there has been a concerted effort to identify viable ways to conserve PPE, including decontamination after use. In this study, we outline a procedure by which PPE may be decontaminated using ultraviolet (UV) radiation in biosafety cabinets (BSCs), a common element of many academic, public health, and hospital laboratories. According to the literature, effective decontamination of N95 respirator masks or surgical masks requires UV-C doses of greater than 1 Jcm−2, which was achieved after 4.3 hours per side when placing the N95 at the bottom of the BSCs tested in this study. We then demonstrated complete inactivation of the human coronavirus NL63 on N95 mask material after 15 minutes of UV-C exposure at 61 cm (232 μWcm−2). Our results provide support to healthcare organizations looking for methods to extend their reserves of PPE.
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Affiliation(s)
- Davis T. Weaver
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | | | - Vishhvaan Gopalakrishnan
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Kyle J. Card
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- Michigan State University, East Lansing, MI, United States of America
| | - Dena Crozier
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Andrew Dhawan
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- Cleveland Clinic, Division of Neurology, Cleveland, OH, United States of America
| | - Mina N. Dinh
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Emily Dolson
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Nathan Farrokhian
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Masahiro Hitomi
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Emily Ho
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Tanush Jagdish
- Dana Farber Cancer Insitute, Harvard University, Boston, MA, United States of America
| | - Eshan S. King
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | | | | | - Nikhil Krishnan
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Gleb Kuzmin
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Ju Li
- Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Jeff Maltas
- University of Michigan, Ann Arbor, MI, United States of America
| | | | - Julia Pelesko
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Jessica A. Scarborough
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Geoff Sedor
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Enze Tian
- Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Gary C. An
- University of Vermont Medical Center, Burlington, VT, United States of America
| | - Sean A. Diehl
- University of Vermont Medical Center, Burlington, VT, United States of America
- * E-mail: (SAD); (JGS)
| | - Jacob G. Scott
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- * E-mail: (SAD); (JGS)
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22
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Gardner A, Ghosh S, Dunowska M, Brightwell G. Virucidal Efficacy of Blue LED and Far-UVC Light Disinfection against Feline Infectious Peritonitis Virus as a Model for SARS-CoV-2. Viruses 2021; 13:1436. [PMID: 34452302 PMCID: PMC8402852 DOI: 10.3390/v13081436] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 07/16/2021] [Accepted: 07/19/2021] [Indexed: 12/17/2022] Open
Abstract
Transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occurs through respiratory droplets passed directly from person to person or indirectly through fomites, such as common use surfaces or objects. The aim of this study was to determine the virucidal efficacy of blue LED (405 nm) and far-UVC (222 nm) light in comparison to standard UVC (254 nm) irradiation for the inactivation of feline infectious peritonitis virus (FIPV) on different matrices as a model for SARS-CoV-2. Wet or dried FIPV on stainless steel, plastic, or paper discs, in the presence or absence of artificial saliva, were exposed to various wavelengths of light for different time periods (1-90 min). Dual activity of blue LED and far-UVC lights were virucidal for most wet and dried FIPV within 4 to 16 min on all matrices. Individual action of blue LED and far-UVC lights were virucidal for wet FIPV but required longer irradiation times (8-90 min) to reach a 4-log reduction. In comparison, LED (265 nm) and germicidal UVC (254 nm) were virucidal on almost all matrices for both wet and dried FIPV within 1 min exposure. UVC was more effective for the disinfection of surfaces as compared to blue LED and far-UVC individually or together. However, dual action of blue LED and far-UVC was virucidal. This combination of lights could be used as a safer alternative to traditional UVC.
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Affiliation(s)
- Amanda Gardner
- AgResearch Ltd., Hopkirk Research Institute, Massey University, Corner University Ave and Library Road, Palmerston North 4442, New Zealand;
| | - Sayani Ghosh
- School of Veterinary Science, Massey University Manawatu (Turitea), Tennent Drive, Palmerston North 4474, New Zealand; (S.G.); (M.D.)
| | - Magdalena Dunowska
- School of Veterinary Science, Massey University Manawatu (Turitea), Tennent Drive, Palmerston North 4474, New Zealand; (S.G.); (M.D.)
| | - Gale Brightwell
- AgResearch Ltd., Hopkirk Research Institute, Massey University, Corner University Ave and Library Road, Palmerston North 4442, New Zealand;
- New Zealand Food Safety Science and Research Centre, Massey University Manawatu (Turitea), Tennent Drive, Palmerston North 4474, New Zealand
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23
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Lo CW, Matsuura R, Iimura K, Wada S, Shinjo A, Benno Y, Nakagawa M, Takei M, Aida Y. UVC disinfects SARS-CoV-2 by induction of viral genome damage without apparent effects on viral morphology and proteins. Sci Rep 2021; 11:13804. [PMID: 34226623 PMCID: PMC8257663 DOI: 10.1038/s41598-021-93231-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 06/22/2021] [Indexed: 12/20/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a pandemic threat worldwide and causes severe health and economic burdens. Contaminated environments, such as personal items and room surfaces, are considered to have virus transmission potential. Ultraviolet C (UVC) light has demonstrated germicidal ability and removes environmental contamination. UVC has inactivated SARS-CoV-2; however, the underlying mechanisms are not clear. It was confirmed here that UVC 253.7 nm, with a dose of 500 μW/cm2, completely inactivated SARS-CoV-2 in a time-dependent manner and reduced virus infectivity by 10-4.9-fold within 30 s. Immunoblotting analysis for viral spike and nucleocapsid proteins showed that UVC treatment did not damage viral proteins. The viral particle morphology remained intact even when the virus completely lost infectivity after UVC irradiation, as observed by transmission electronic microscopy. In contrast, UVC irradiation-induced genome damage was identified using the newly developed long reverse-transcription quantitative-polymerase chain reaction (RT-qPCR) assay, but not conventional RT-qPCR. The six developed long RT-PCR assays that covered the full-length viral genome clearly indicated a negative correlation between virus infectivity and UVC irradiation-induced genome damage (R2 ranging from 0.75 to 0.96). Altogether, these results provide evidence that UVC inactivates SARS-CoV-2 through the induction of viral genome damage.
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Affiliation(s)
- Chieh-Wen Lo
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, the University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
- Division of Hematology and Rheumatology, Department of Medicine, Nihon University School of Medicine, 30-1 Oyaguchi, Kami-Cho, Itabashi, Tokyo, 173-8610, Japan
| | - Ryosuke Matsuura
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, the University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
- Division of Hematology and Rheumatology, Department of Medicine, Nihon University School of Medicine, 30-1 Oyaguchi, Kami-Cho, Itabashi, Tokyo, 173-8610, Japan
| | - Kazuki Iimura
- Division of Hematology and Rheumatology, Department of Medicine, Nihon University School of Medicine, 30-1 Oyaguchi, Kami-Cho, Itabashi, Tokyo, 173-8610, Japan
- Farmroid Co.,Ltd., 3-22-4 Funado, Itabashi-ku, Tokyo, 174-0041, Japan
| | - Satoshi Wada
- Division of Hematology and Rheumatology, Department of Medicine, Nihon University School of Medicine, 30-1 Oyaguchi, Kami-Cho, Itabashi, Tokyo, 173-8610, Japan
- Photonics Control Technology Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Atsushi Shinjo
- Photonics Control Technology Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Yoshimi Benno
- Benno Laboratory, Baton Zone Program, RIKEN Cluster for Science, Technology and Innovation Hub, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Masaru Nakagawa
- Division of Hematology and Rheumatology, Department of Medicine, Nihon University School of Medicine, 30-1 Oyaguchi, Kami-Cho, Itabashi, Tokyo, 173-8610, Japan
| | - Masami Takei
- Division of Hematology and Rheumatology, Department of Medicine, Nihon University School of Medicine, 30-1 Oyaguchi, Kami-Cho, Itabashi, Tokyo, 173-8610, Japan
| | - Yoko Aida
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, the University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
- Division of Hematology and Rheumatology, Department of Medicine, Nihon University School of Medicine, 30-1 Oyaguchi, Kami-Cho, Itabashi, Tokyo, 173-8610, Japan.
- Benno Laboratory, Baton Zone Program, RIKEN Cluster for Science, Technology and Innovation Hub, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
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24
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Ulloa S, Bravo C, Ramirez E, Fasce R, Fernandez J. Inactivation of SARS-CoV-2 isolates from lineages B.1.1.7 (Alpha), P.1 (Gamma) and B.1.110 by heating and UV irradiation. J Virol Methods 2021; 295:114216. [PMID: 34171342 PMCID: PMC8219296 DOI: 10.1016/j.jviromet.2021.114216] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 06/19/2021] [Accepted: 06/20/2021] [Indexed: 12/24/2022]
Abstract
Currently, the rapid global spread of SARS-CoV-2 is related to G clade (including GH, GR, GRY and GV clades), which are associated with more than 98 % of sequenced viral isolates worldwide. The unprecedented velocity of spread of SARS-CoV-2 outbreak represents a critical need for prevention strategies. Vaccines are recently being available and antiviral drugs have shown limited efficacy in COVID-19 patients. Thus, it is needed to know how to reduce the infectivity of the virus by different physicochemical conditions in order to prevent exposure to contaminated material. This work describes heating and irradiating UV-C light procedures to reduce the infectivity of SARS-CoV-2 belonging to different three lineages. Results of physicochemical treatment showed no differences among viral lineages. Analytical conditions for efficient inactivation of SARS-CoV-2 were determined.
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Affiliation(s)
- S Ulloa
- Molecular Genetics Sub Department, Institute of Public Health of Chile, Santiago, Chile
| | - C Bravo
- Molecular Genetics Sub Department, Institute of Public Health of Chile, Santiago, Chile
| | - E Ramirez
- Viral Diseases Sub Department, Institute of Public Health of Chile, Santiago, Chile
| | - R Fasce
- Viral Diseases Sub Department, Institute of Public Health of Chile, Santiago, Chile
| | - J Fernandez
- Molecular Genetics Sub Department, Institute of Public Health of Chile, Santiago, Chile.
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25
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Peters A, Palomo R, Ney H, Lotfinejad N, Zingg W, Parneix P, Pittet D. The COVID-19 pandemic and N95 masks: reusability and decontamination methods. Antimicrob Resist Infect Control 2021; 10:83. [PMID: 34051855 PMCID: PMC8164050 DOI: 10.1186/s13756-021-00921-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 03/02/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND With the current SARS-CoV-2 pandemic, many healthcare facilities are lacking a steady supply of masks worldwide. This emergency situation warrants the taking of extraordinary measures to minimize the negative health impact from an insufficient supply of masks. The decontamination, and reuse of healthcare workers' N95/FFP2 masks is a promising solution which needs to overcome several pitfalls to become a reality. AIM The overall aim of this article is to provide the reader with a quick overview of the various methods for decontamination and the potential issues to be taken into account when deciding to reuse masks. Ultraviolet germicidal irradiation (UVGI), hydrogen peroxide, steam, ozone, ethylene oxide, dry heat and moist heat have all been methods studied in the context of the pandemic. The article first focuses on the logistical implementation of a decontamination system in its entirety, and then aims to summarize and analyze the different available methods for decontamination. METHODS In order to have a clear understanding of the research that has already been done, we conducted a systematic literature review for the questions: what are the tested methods for decontaminating N95/FFP2 masks, and what impact do those methods have on the microbiological contamination and physical integrity of the masks? We used the results of a systematic review on the methods of microbiological decontamination of masks to make sure we covered all of the recommended methods for mask reuse. To this systematic review we added articles and studies relevant to the subject, but that were outside the limits of the systematic review. These include a number of studies that performed important fit and function tests on the masks but took their microbiological outcomes from the existing literature and were thus excluded from the systematic review, but useful for this paper. We also used additional unpublished studies and internal communication from the University of Geneva Hospitals and partner institutions. RESULTS This paper analyzes the acceptable methods for respirator decontamination and reuse, and scores them according to a number of variables that we have defined as being crucial (including cost, risk, complexity, time, etc.) to help healthcare facilities decide which method of decontamination is right for them. CONCLUSION We provide a resource for healthcare institutions looking at making informed decisions about respirator decontamination. This informed decision making will help to improve infection prevention and control measures, and protect healthcare workers during this crucial time. The overall take home message is that institutions should not reuse respirators unless they have to. In the case of an emergency situation, there are some safe ways to decontaminate them.
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Affiliation(s)
- Alexandra Peters
- Infection Control Programme, University of Geneva Hospitals and Faculty of Medicine, 4 Rue Gabrielle-Perret-Gentil, 1211, Geneva 14, Switzerland
| | | | - Hervé Ney
- Infection Control Programme, University of Geneva Hospitals and Faculty of Medicine, 4 Rue Gabrielle-Perret-Gentil, 1211, Geneva 14, Switzerland
| | - Nasim Lotfinejad
- Department of Research, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Walter Zingg
- Infection Control Programme, University of Geneva Hospitals and Faculty of Medicine, 4 Rue Gabrielle-Perret-Gentil, 1211, Geneva 14, Switzerland
| | - Pierre Parneix
- Nouvelle Aquitaine Healthcare-Associated Infection Control Centre, Bordeaux University Hospital, Bordeaux, France
| | - Didier Pittet
- Infection Control Programme, University of Geneva Hospitals and Faculty of Medicine, 4 Rue Gabrielle-Perret-Gentil, 1211, Geneva 14, Switzerland.
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26
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Chiappa F, Frascella B, Vigezzi GP, Moro M, Diamanti L, Gentile L, Lago P, Clementi N, Signorelli C, Mancini N, Odone A. The efficacy of ultraviolet light-emitting technology against coronaviruses: a systematic review. J Hosp Infect 2021; 114:63-78. [PMID: 34029626 PMCID: PMC8139389 DOI: 10.1016/j.jhin.2021.05.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/11/2021] [Accepted: 05/13/2021] [Indexed: 12/13/2022]
Abstract
The ongoing pandemic of COVID-19 has underlined the importance of adopting effective infection prevention and control (IPC) measures in hospital and community settings. Ultraviolet (UV)-based technologies represent promising IPC tools: their effective application for sanitation has been extensively evaluated in the past but scant, heterogeneous and inconclusive evidence is available on their effect on SARS-CoV-2 transmission. With the aim of pooling the available evidence on the efficacy of UV technologies against coronaviruses, we conducted a systematic review following PRISMA guidelines, searching Medline, Embase and the Cochrane Library, and the main clinical trials' registries (WHO ICTRP, ClinicalTrials.gov, Cochrane and EU Clinical Trial Register). Quantitative data on studies' interventions were summarized in tables, pooled by different coronavirus species and strain, UV source, characteristics of UV light exposure and outcomes. Eighteen papers met our inclusion criteria, published between 1972 and 2020. Six focused on SARS-CoV-2, four on SARS-CoV-1, one on MERS-CoV, three on seasonal coronaviruses, and four on animal coronaviruses. All were experimental studies. Overall, despite wide heterogenicity within included studies, complete inactivation of coronaviruses on surfaces or aerosolized, including SARS-CoV-2, was reported to take a maximum exposure time of 15 min and to need a maximum distance from the UV emitter of up to 1 m. Advances in UV-based technologies in the field of sanitation and their proved high virucidal potential against SARS-CoV-2 support their use for IPC in hospital and community settings and their contribution towards ending the COVID-19 pandemic. National and international guidelines are to be updated and parameters and conditions of use need to be identified to ensure both efficacy and safety of UV technology application for effective infection prevention and control in both healthcare and non-healthcare settings.
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Affiliation(s)
- F Chiappa
- School of Public Health, University Vita-Salute San Raffaele, Milan, Italy
| | - B Frascella
- School of Public Health, University Vita-Salute San Raffaele, Milan, Italy
| | - G P Vigezzi
- School of Public Health, University Vita-Salute San Raffaele, Milan, Italy
| | - M Moro
- Infection Control Committee, IRCCS San Raffaele Hospital, Milan, Italy
| | - L Diamanti
- Clinical Engineering Unit, IRCCS San Raffaele Hospital, Milan, Italy; HTA Committee, IRCCS San Raffaele Hospital, Milan, Italy
| | - L Gentile
- Clinical Engineering Unit, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - P Lago
- Clinical Engineering Unit, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - N Clementi
- Laboratory of Microbiology and Virology, University Vita-Salute San Raffaele, Milan, Italy
| | - C Signorelli
- School of Medicine, University Vita-Salute San Raffaele, Milan, Italy
| | - N Mancini
- Laboratory of Microbiology and Virology, University Vita-Salute San Raffaele, Milan, Italy
| | - A Odone
- HTA Committee, IRCCS San Raffaele Hospital, Milan, Italy; Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy.
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Goldberg LA, Jorritsma J, Komjáthy J, Lapinskas J. Increasing efficacy of contact-tracing applications by user referrals and stricter quarantining. PLoS One 2021; 16:e0250435. [PMID: 34010333 PMCID: PMC8133478 DOI: 10.1371/journal.pone.0250435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 04/07/2021] [Indexed: 12/22/2022] Open
Abstract
We study the effects of two mechanisms which increase the efficacy of contact-tracing applications (CTAs) such as the mobile phone contact-tracing applications that have been used during the COVID-19 epidemic. The first mechanism is the introduction of user referrals. We compare four scenarios for the uptake of CTAs-(1) the p% of individuals that use the CTA are chosen randomly, (2) a smaller initial set of randomly-chosen users each refer a contact to use the CTA, achieving p% in total, (3) a small initial set of randomly-chosen users each refer around half of their contacts to use the CTA, achieving p% in total, and (4) for comparison, an idealised scenario in which the p% of the population that uses the CTA is the p% with the most contacts. Using agent-based epidemiological models incorporating a geometric space, we find that, even when the uptake percentage p% is small, CTAs are an effective tool for mitigating the spread of the epidemic in all scenarios. Moreover, user referrals significantly improve efficacy. In addition, it turns out that user referrals reduce the quarantine load. The second mechanism for increasing the efficacy of CTAs is tuning the severity of quarantine measures. Our modelling shows that using CTAs with mild quarantine measures is effective in reducing the maximum hospital load and the number of people who become ill, but leads to a relatively high quarantine load, which may cause economic disruption. Fortunately, under stricter quarantine measures, the advantages are maintained but the quarantine load is reduced. Our models incorporate geometric inhomogeneous random graphs to study the effects of the presence of super-spreaders and of the absence of long-distant contacts (e.g., through travel restrictions) on our conclusions.
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Affiliation(s)
- Leslie Ann Goldberg
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Joost Jorritsma
- Department of Mathematics and Computer Science, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Júlia Komjáthy
- Department of Mathematics and Computer Science, Eindhoven University of Technology, Eindhoven, Netherlands
| | - John Lapinskas
- Department of Computer Science, University of Bristol, Bristol, United Kingdom
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Barbora A, Minnes R. Targeted antiviral treatment using non-ionizing radiation therapy for SARS-CoV-2 and viral pandemics preparedness: Technique, methods and practical notes for clinical application. PLoS One 2021; 16:e0251780. [PMID: 33989354 PMCID: PMC8121356 DOI: 10.1371/journal.pone.0251780] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 05/04/2021] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE Pandemic outbreaks necessitate effective responses to rapidly mitigate and control the spread of disease and eliminate the causative organism(s). While conventional chemical and biological solutions to these challenges are characteristically slow to develop and reach public availability; recent advances in device components operating at Super High Frequency (SHF) bands (3-30 GHz) of the electromagnetic spectrum enable novel approaches to such problems. METHODS Based on experimentally documented evidence, a clinically relevant in situ radiation procedure to reduce viral loads in patients is devised and presented. Adapted to the currently available medical device technology to cause viral membrane fracture, this procedure selectively inactivates virus particles by forced oscillations arising from Structure Resonant Energy Transfer (SRET) thereby reducing infectivity and disease progression. RESULTS Effective resonant frequencies for pleiomorphic Coronavirus SARS-CoV-2 is calculated to be in the 10-17 GHz range. Using the relation y = -3.308x + 42.9 with x and y representing log10 number of virus particles and the clinical throat swab Ct value respectively; in situ patient-specific exposure duration of ~15x minutes can be utilized to inactivate up to 100% of virus particles in the throat-lung lining, using an irradiation dose of 14.5 ± 1 W/m2; which is within the 200 W/m2 safety standard stipulated by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). CONCLUSIONS The treatment is designed to make patients less contagious enhancing faster recoveries and enabling timely control of a spreading pandemic. ADVANCES IN KNOWLEDGE The article provides practically applicable parameters for effective clinical adaptation of this technique to the current pandemic at different levels of healthcare infrastructure and disease prevention besides enabling rapid future viral pandemics response.
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Affiliation(s)
- Ayan Barbora
- Department of Physics, Faculty of Natural Sciences, Ariel University, Ariel, Israel
- * E-mail: (AB); (RM)
| | - Refael Minnes
- Department of Physics, Faculty of Natural Sciences, Ariel University, Ariel, Israel
- * E-mail: (AB); (RM)
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Ailioaie LM, Litscher G. Probiotics, Photobiomodulation, and Disease Management: Controversies and Challenges. Int J Mol Sci 2021; 22:ijms22094942. [PMID: 34066560 PMCID: PMC8124384 DOI: 10.3390/ijms22094942] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 04/26/2021] [Accepted: 04/29/2021] [Indexed: 02/06/2023] Open
Abstract
In recent decades, researchers around the world have been studying intensively how micro-organisms that are present inside living organisms could affect the main processes of life, namely health and pathological conditions of mind or body. They discovered a relationship between the whole microbial colonization and the initiation and development of different medical disorders. Besides already known probiotics, novel products such as postbiotics and paraprobiotics have been developed in recent years to create new non-viable micro-organisms or bacterial-free extracts, which can provide benefits to the host with additional bioactivity to probiotics, but without the risk of side effects. The best alternatives in the use of probiotics and postbiotics to maintain the health of the intestinal microbiota and to prevent the attachment of pathogens to children and adults are highlighted and discussed as controversies and challenges. Updated knowledge of the molecular and cellular mechanisms involved in the balance between microbiota and immune system for the introspection on the gut-lung-brain axis could reveal the latest benefits and perspectives of applied photobiomics for health. Multiple interconditioning between photobiomodulation (PBM), probiotics, and the human microbiota, their effects on the human body, and their implications for the management of viral infectious diseases is essential. Coupled complex PBM and probiotic interventions can control the microbiome, improve the activity of the immune system, and save the lives of people with immune imbalances. There is an urgent need to seek and develop innovative treatments to successfully interact with the microbiota and the human immune system in the coronavirus crisis. In the near future, photobiomics and metabolomics should be applied innovatively in the SARS-CoV-2 crisis (to study and design new therapies for COVID-19 immediately), to discover how bacteria can help us through adequate energy biostimulation to combat this pandemic, so that we can find the key to the hidden code of communication between RNA viruses, bacteria, and our body.
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Affiliation(s)
- Laura Marinela Ailioaie
- Department of Medical Physics, Alexandru Ioan Cuza University, 11 Carol I Boulevard, 700506 Iasi, Romania;
- Ultramedical & Laser Clinic, 83 Arcu Street, 700135 Iasi, Romania
| | - Gerhard Litscher
- Research Unit of Biomedical Engineering in Anesthesia and Intensive Care Medicine, Research Unit for Complementary and Integrative Laser Medicine, and Traditional Chinese Medicine (TCM) Research Center Graz, Medical University of Graz, Auenbruggerplatz 39, 8036 Graz, Austria
- Correspondence: ; Tel.: +43-316-385-83907
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Zupin L, Gratton R, Fontana F, Clemente L, Pascolo L, Ruscio M, Crovella S. Blue photobiomodulation LED therapy impacts SARS-CoV-2 by limiting its replication in Vero cells. J Biophotonics 2021; 14:e202000496. [PMID: 33619888 PMCID: PMC7995021 DOI: 10.1002/jbio.202000496] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 05/24/2023]
Abstract
The study of any intervention able to counteract SARS-CoV-2 pandemic is considerably envisaged. It was previously shown, in in vitro models of infections, that the LED blue light is able to decrease the viral load of HSV-1 and ZIKV. In our study, LED photobiomodulation therapy (PBMT) at blue wavelengths (450, 454 and 470 nm) was tested in an in vitro model of SARS-CoV-2 infection, employing three experimental settings: SARS-CoV-2 was irradiated and then transferred to cells; already infected cells were irradiated; cells were irradiated prior to infection. A decrement of the viral load was observed when previously infected cells were irradiated with all three tested wavelengths and relevant effects were registered especially at 48 hours post-infection, possibly suggesting that the blue light could interfere with the intracellular viral replication machinery. Our in vitro findings could represent the starting point for translational applications of PBMT as a supportive approach to fight SARS-CoV-2.
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Affiliation(s)
- Luisa Zupin
- Medical Genetics, Institute for Maternal and Child Health—IRCCS “Burlo Garofolo”TriesteItaly
| | - Rossella Gratton
- Medical Genetics, Institute for Maternal and Child Health—IRCCS “Burlo Garofolo”TriesteItaly
| | - Francesco Fontana
- Division of Laboratory MedicineUniversity Hospital Giuliano Isontina (ASU GI)TriesteItaly
| | - Libera Clemente
- Division of Laboratory MedicineUniversity Hospital Giuliano Isontina (ASU GI)TriesteItaly
| | - Lorella Pascolo
- Obstetrics and GynecologyInstitute for Maternal and Child Health—IRCCS “Burlo Garofolo”TriesteItaly
| | - Maurizio Ruscio
- Division of Laboratory MedicineUniversity Hospital Giuliano Isontina (ASU GI)TriesteItaly
| | - Sergio Crovella
- Department of Biological and Environmental Sciences, College of Arts and SciencesUniversity of QatarDohaQatar
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Bormann M, Alt M, Schipper L, van de Sand L, Otte M, Meister TL, Dittmer U, Witzke O, Steinmann E, Krawczyk A. Disinfection of SARS-CoV-2 Contaminated Surfaces of Personal Items with UVC-LED Disinfection Boxes. Viruses 2021; 13:v13040598. [PMID: 33807470 PMCID: PMC8065986 DOI: 10.3390/v13040598] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/24/2021] [Accepted: 03/29/2021] [Indexed: 01/08/2023] Open
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted from person to person by close contact, small aerosol respiratory droplets, and potentially via contact with contaminated surfaces. Herein, we investigated the effectiveness of commercial UVC-LED disinfection boxes in inactivating SARS-CoV-2-contaminated surfaces of personal items. We contaminated glass, metal, and plastic samples representing the surfaces of personal items such as smartphones, coins, or credit cards with SARS-CoV-2 formulated in an organic matrix mimicking human respiratory secretions. For disinfection, the samples were placed at different distances from UVC emitting LEDs inside commercial UVC-LED disinfection boxes and irradiated for different time periods (up to 10 min). High viral loads of SARS-CoV-2 were effectively inactivated on all surfaces after 3 min of irradiation. Even 10 s of UVC-exposure strongly reduced viral loads. Thus, UVC-LED boxes proved to be an effective method for disinfecting SARS-CoV-2-contaminated surfaces that are typically found on personal items.
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Affiliation(s)
- Maren Bormann
- West German Centre of Infectious Diseases, Department of Infectious Diseases, Universitätsmedizin Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Mira Alt
- West German Centre of Infectious Diseases, Department of Infectious Diseases, Universitätsmedizin Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Leonie Schipper
- West German Centre of Infectious Diseases, Department of Infectious Diseases, Universitätsmedizin Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Lukas van de Sand
- West German Centre of Infectious Diseases, Department of Infectious Diseases, Universitätsmedizin Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Mona Otte
- West German Centre of Infectious Diseases, Department of Infectious Diseases, Universitätsmedizin Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Toni Luise Meister
- Department of Molecular and Medical Virology, Faculty of Medicine, Ruhr University Bochum, 44801 Bochum, Germany
| | - Ulf Dittmer
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Oliver Witzke
- West German Centre of Infectious Diseases, Department of Infectious Diseases, Universitätsmedizin Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Eike Steinmann
- Department of Molecular and Medical Virology, Faculty of Medicine, Ruhr University Bochum, 44801 Bochum, Germany
| | - Adalbert Krawczyk
- West German Centre of Infectious Diseases, Department of Infectious Diseases, Universitätsmedizin Essen, University Duisburg-Essen, 45147 Essen, Germany
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany
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Karapiperis C, Kouklis P, Papastratos S, Chasapi A, Danchin A, Angelis L, Ouzounis CA. A Strong Seasonality Pattern for Covid-19 Incidence Rates Modulated by UV Radiation Levels. Viruses 2021; 13:v13040574. [PMID: 33805449 PMCID: PMC8067063 DOI: 10.3390/v13040574] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 01/04/2023] Open
Abstract
The Covid-19 pandemic has required nonpharmaceutical interventions, primarily physical distancing, personal hygiene and face mask use, to limit community transmission, irrespective of seasons. In fact, the seasonality attributes of this pandemic remain one of its biggest unknowns. Early studies based on past experience from respiratory diseases focused on temperature or humidity, with disappointing results. Our hypothesis that ultraviolet (UV) radiation levels might be a factor and a more appropriate parameter has emerged as an alternative to assess seasonality and exploit it for public health policies. Using geographical, socioeconomic and epidemiological criteria, we selected twelve North-equatorial-South countries with similar characteristics. We then obtained UV levels, mobility and Covid-19 daily incidence rates for nearly the entire 2020. Using machine learning, we demonstrated that UV radiation strongly associated with incidence rates, more so than mobility did, indicating that UV is a key seasonality indicator for Covid-19, irrespective of the initial conditions of the epidemic. Our findings can inform the implementation of public health emergency measures, partly based on seasons in the Northern and Southern Hemispheres, as the pandemic unfolds into 2021.
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Affiliation(s)
- Christos Karapiperis
- School of Informatics, Aristotle University of Thessaloniki, GR-54124 Thessalonica, Greece; (C.K.); (L.A.)
- Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas (CERTH), Thermi, GR-57001 Thessalonica, Greece; (S.P.); (A.C.)
| | - Panos Kouklis
- Laboratory of Biology, Medical School, University of Ioannina, GR-45110 Ioannina, Greece;
- Department of Biomedical Research, Institute of Molecular Biology & Biotechnology, Foundation for Research & Technology Hellas (FORTH), GR-45115 Ioannina, Greece
| | - Stelios Papastratos
- Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas (CERTH), Thermi, GR-57001 Thessalonica, Greece; (S.P.); (A.C.)
| | - Anastasia Chasapi
- Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas (CERTH), Thermi, GR-57001 Thessalonica, Greece; (S.P.); (A.C.)
| | - Antoine Danchin
- Kodikos Labs, F-69007 Lyon, France;
- Institut Cochin, F-75013 Paris, France
| | - Lefteris Angelis
- School of Informatics, Aristotle University of Thessaloniki, GR-54124 Thessalonica, Greece; (C.K.); (L.A.)
| | - Christos A. Ouzounis
- School of Informatics, Aristotle University of Thessaloniki, GR-54124 Thessalonica, Greece; (C.K.); (L.A.)
- Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas (CERTH), Thermi, GR-57001 Thessalonica, Greece; (S.P.); (A.C.)
- Correspondence:
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Loveday EK, Hain KS, Kochetkova I, Hedges JF, Robison A, Snyder DT, Brumfield SK, Young MJ, Jutila MA, Chang CB, Taylor MP. Effect of Inactivation Methods on SARS-CoV-2 Virion Protein and Structure. Viruses 2021; 13:562. [PMID: 33810401 PMCID: PMC8066162 DOI: 10.3390/v13040562] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 03/22/2021] [Indexed: 12/31/2022] Open
Abstract
The risk posed by Severe Acute Respiratory Syndrome Coronavirus -2 (SARS-CoV-2) dictates that live-virus research is conducted in a biosafety level 3 (BSL3) facility. Working with SARS-CoV-2 at lower biosafety levels can expedite research yet requires the virus to be fully inactivated. In this study, we validated and compared two protocols for inactivating SARS-CoV-2: heat treatment and ultraviolet irradiation. The two methods were optimized to render the virus completely incapable of infection while limiting the destructive effects of inactivation. We observed that 15 min of incubation at 65 °C completely inactivates high titer viral stocks. Complete inactivation was also achieved with minimal amounts of UV power (70,000 µJ/cm2), which is 100-fold less power than comparable studies. Once validated, the two methods were then compared for viral RNA quantification, virion purification, and antibody detection assays. We observed that UV irradiation resulted in a 2-log reduction of detectable genomes compared to heat inactivation. Protein yield following virion enrichment was equivalent for all inactivation conditions, but the quality of resulting viral proteins and virions were differentially impacted depending on inactivation method and time. Here, we outline the strengths and weaknesses of each method so that investigators might choose the one which best meets their research goals.
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Affiliation(s)
- Emma K. Loveday
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, MT 59717, USA; (E.K.L.); (C.B.C.)
| | - Kyle S. Hain
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Irina Kochetkova
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Jodi F. Hedges
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Amanda Robison
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Deann T. Snyder
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Susan K. Brumfield
- Department of Plant Science and Plant Pathology, Montana State University; Bozeman, MT 59717, USA; (S.K.B.); (M.J.Y.)
| | - Mark J. Young
- Department of Plant Science and Plant Pathology, Montana State University; Bozeman, MT 59717, USA; (S.K.B.); (M.J.Y.)
| | - Mark A. Jutila
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Connie B. Chang
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, MT 59717, USA; (E.K.L.); (C.B.C.)
| | - Matthew P. Taylor
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
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Biasin M, Bianco A, Pareschi G, Cavalleri A, Cavatorta C, Fenizia C, Galli P, Lessio L, Lualdi M, Tombetti E, Ambrosi A, Redaelli EMA, Saulle I, Trabattoni D, Zanutta A, Clerici M. UV-C irradiation is highly effective in inactivating SARS-CoV-2 replication. Sci Rep 2021; 11:6260. [PMID: 33737536 PMCID: PMC7973506 DOI: 10.1038/s41598-021-85425-w] [Citation(s) in RCA: 135] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 02/22/2021] [Indexed: 12/18/2022] Open
Abstract
The potential virucidal effects of UV-C irradiation on SARS-CoV-2 were experimentally evaluated for different illumination doses and virus concentrations (1000, 5, 0.05 MOI). At a virus density comparable to that observed in SARS-CoV-2 infection, an UV-C dose of just 3.7 mJ/cm2 was sufficient to achieve a more than 3-log inactivation without any sign of viral replication. Moreover, a complete inactivation at all viral concentrations was observed with 16.9 mJ/cm2. These results could explain the epidemiological trends of COVID-19 and are important for the development of novel sterilizing methods to contain SARS-CoV-2 infection.
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Affiliation(s)
- Mara Biasin
- 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
| | - Giovanni Pareschi
- Italian National Institute for Astrophysics (INAF)-Brera Astronomical Observatory, Merate, Italy
| | - Adalberto Cavalleri
- Epidemiology and Prevention Unit, IRCCS Foundation, Istituto Nazionale dei Tumori, Milan, Italy
| | - Claudia Cavatorta
- Epidemiology and Prevention Unit, IRCCS Foundation, Istituto Nazionale dei Tumori, Milan, Italy
| | - Claudio Fenizia
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
- University Life and Health San Raffaele, Milan, Italy
| | - Paola Galli
- Italian National Institute for Astrophysics (INAF)-Brera Astronomical Observatory, Merate, Italy
| | - Luigi Lessio
- Italian National Institute for Astrophysics (INAF)-Padova Astronomical Observatory, Padova, Italy
| | - Manuela Lualdi
- Department of Imaging Diagnostic and Radioterapy, IRCCS Foundation, Istituto Nazionale dei Tumori, Milan, Italy
| | - Enrico Tombetti
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
| | | | | | - Irma Saulle
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Daria Trabattoni
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
| | - Alessio Zanutta
- Italian National Institute for Astrophysics (INAF)-Brera Astronomical Observatory, Merate, 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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Biasin M, Bianco A, Pareschi G, Cavalleri A, Cavatorta C, Fenizia C, Galli P, Lessio L, Lualdi M, Tombetti E, Ambrosi A, Redaelli EMA, Saulle I, Trabattoni D, Zanutta A, Clerici M. UV-C irradiation is highly effective in inactivating SARS-CoV-2 replication. Sci Rep 2021. [PMID: 33737536 DOI: 10.1101/2020.06.05.20123463] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023] Open
Abstract
The potential virucidal effects of UV-C irradiation on SARS-CoV-2 were experimentally evaluated for different illumination doses and virus concentrations (1000, 5, 0.05 MOI). At a virus density comparable to that observed in SARS-CoV-2 infection, an UV-C dose of just 3.7 mJ/cm2 was sufficient to achieve a more than 3-log inactivation without any sign of viral replication. Moreover, a complete inactivation at all viral concentrations was observed with 16.9 mJ/cm2. These results could explain the epidemiological trends of COVID-19 and are important for the development of novel sterilizing methods to contain SARS-CoV-2 infection.
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Affiliation(s)
- Mara Biasin
- 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
| | - Giovanni Pareschi
- Italian National Institute for Astrophysics (INAF)-Brera Astronomical Observatory, Merate, Italy
| | - Adalberto Cavalleri
- Epidemiology and Prevention Unit, IRCCS Foundation, Istituto Nazionale dei Tumori, Milan, Italy
| | - Claudia Cavatorta
- Epidemiology and Prevention Unit, IRCCS Foundation, Istituto Nazionale dei Tumori, Milan, Italy
| | - Claudio Fenizia
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
- University Life and Health San Raffaele, Milan, Italy
| | - Paola Galli
- Italian National Institute for Astrophysics (INAF)-Brera Astronomical Observatory, Merate, Italy
| | - Luigi Lessio
- Italian National Institute for Astrophysics (INAF)-Padova Astronomical Observatory, Padova, Italy
| | - Manuela Lualdi
- Department of Imaging Diagnostic and Radioterapy, IRCCS Foundation, Istituto Nazionale dei Tumori, Milan, Italy
| | - Enrico Tombetti
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
| | | | | | - Irma Saulle
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Daria Trabattoni
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, Milan, Italy
| | - Alessio Zanutta
- Italian National Institute for Astrophysics (INAF)-Brera Astronomical Observatory, Merate, 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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Jureka AS, Williams CG, Basler CF. Pulsed Broad-Spectrum UV Light Effectively Inactivates SARS-CoV-2 on Multiple Surfaces and N95 Material. Viruses 2021; 13:460. [PMID: 33799842 PMCID: PMC7998866 DOI: 10.3390/v13030460] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/02/2021] [Accepted: 03/09/2021] [Indexed: 12/11/2022] Open
Abstract
The ongoing SARS-CoV-2 pandemic has resulted in an increased need for technologies capable of efficiently disinfecting public spaces as well as personal protective equipment. UV light disinfection is a well-established method for inactivating respiratory viruses. Here, we have determined that broad-spectrum, pulsed UV light is effective at inactivating SARS-CoV-2 on multiple surfaces in vitro. For hard, non-porous surfaces, we observed that SARS-CoV-2 was inactivated to undetectable levels on plastic and glass with a UV dose of 34.9 mJ/cm2 and stainless steel with a dose of 52.5 mJ/cm2. We also observed that broad-spectrum, pulsed UV light is effective at reducing SARS-CoV-2 on N95 respirator material to undetectable levels with a dose of 103 mJ/cm2. We included UV dosimeter cards that provide a colorimetric readout of UV dose and demonstrated their utility as a means to confirm desired levels of exposure were reached. Together, the results presented here demonstrate that broad-spectrum, pulsed UV light is an effective technology for the in vitro inactivation of SARS-CoV-2 on multiple surfaces.
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Affiliation(s)
| | | | - Christopher F. Basler
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA; (A.S.J.); (C.G.W.)
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Gidari A, Sabbatini S, Bastianelli S, Pierucci S, Busti C, Bartolini D, Stabile AM, Monari C, Galli F, Rende M, Cruciani G, Francisci D. SARS-CoV-2 Survival on Surfaces and the Effect of UV-C Light. Viruses 2021; 13:v13030408. [PMID: 33807521 PMCID: PMC7998261 DOI: 10.3390/v13030408] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/24/2021] [Accepted: 03/02/2021] [Indexed: 12/23/2022] Open
Abstract
The aim of this study was to establish the persistence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on inanimate surfaces such as plastic, stainless steel, and glass during UV-C irradiation which is a physical means commonly utilized in sanitization procedures. The viral inactivation rate, virus half-life, and percentage of titer reduction after UV-C irradiation were assessed. Infectivity was maintained on plastic and glass until 120 h and on stainless steel until 72 h. The virus half-life was 5.3, 4.4, and 4.2 h on plastic, stainless steel, and glass, respectively. In all cases, titer decay was >99% after drop drying. UV-C irradiation efficiently reduced virus titer (99.99%), with doses ranging from 10.25 to 23.71 mJ/cm2. Plastic and stainless steel needed higher doses to achieve target reduction. The total inactivation of SARS-CoV-2 on glass was obtained with the lower dose applied. SARS-CoV-2 survival can be long lasting on inanimate surfaces. It is worth recommending efficient disinfection protocols as a measure of prevention of viral spread. UV-C can provide rapid, efficient and sustainable sanitization procedures of different materials and surfaces. The dosages and mode of irradiation are important parameters to consider in their implementation as an important means to fight the SARS-CoV-2 pandemic.
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Affiliation(s)
- Anna Gidari
- Department of Medicine and Surgery, Clinic of Infectious Diseases, “Santa Maria della Misericordia” Hospital, University of Perugia, 06129 Perugia, Italy; (S.B.); (S.P.); (C.B.); (D.F.)
- Correspondence:
| | - Samuele Sabbatini
- Department of Medicine and Surgery, Medical Microbiology Section, University of Perugia, 06129 Perugia, Italy; (S.S.); (C.M.)
| | - Sabrina Bastianelli
- Department of Medicine and Surgery, Clinic of Infectious Diseases, “Santa Maria della Misericordia” Hospital, University of Perugia, 06129 Perugia, Italy; (S.B.); (S.P.); (C.B.); (D.F.)
| | - Sara Pierucci
- Department of Medicine and Surgery, Clinic of Infectious Diseases, “Santa Maria della Misericordia” Hospital, University of Perugia, 06129 Perugia, Italy; (S.B.); (S.P.); (C.B.); (D.F.)
| | - Chiara Busti
- Department of Medicine and Surgery, Clinic of Infectious Diseases, “Santa Maria della Misericordia” Hospital, University of Perugia, 06129 Perugia, Italy; (S.B.); (S.P.); (C.B.); (D.F.)
| | - Desirée Bartolini
- Department of Pharmaceutical Sciences, Unit of Nutrition and Clinical Biochemistry, University of Perugia, 06122 Perugia, Italy; (D.B.); (F.G.)
| | - Anna Maria Stabile
- Department of Medicine and Surgery, Unit of Human, Clinical and Forensic Anatomy, University of Perugia, 06129 Perugia, Italy; (A.M.S.); (M.R.)
| | - Claudia Monari
- Department of Medicine and Surgery, Medical Microbiology Section, University of Perugia, 06129 Perugia, Italy; (S.S.); (C.M.)
| | - Francesco Galli
- Department of Pharmaceutical Sciences, Unit of Nutrition and Clinical Biochemistry, University of Perugia, 06122 Perugia, Italy; (D.B.); (F.G.)
| | - Mario Rende
- Department of Medicine and Surgery, Unit of Human, Clinical and Forensic Anatomy, University of Perugia, 06129 Perugia, Italy; (A.M.S.); (M.R.)
| | - Gabriele Cruciani
- Department of Chemistry, Biology and Biotechnology, University of Perugia, 06123 Perugia, Italy;
| | - Daniela Francisci
- Department of Medicine and Surgery, Clinic of Infectious Diseases, “Santa Maria della Misericordia” Hospital, University of Perugia, 06129 Perugia, Italy; (S.B.); (S.P.); (C.B.); (D.F.)
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Minamikawa T, Koma T, Suzuki A, Mizuno T, Nagamatsu K, Arimochi H, Tsuchiya K, Matsuoka K, Yasui T, Yasutomo K, Nomaguchi M. Quantitative evaluation of SARS-CoV-2 inactivation using a deep ultraviolet light-emitting diode. Sci Rep 2021; 11:5070. [PMID: 33658595 PMCID: PMC7930116 DOI: 10.1038/s41598-021-84592-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 02/18/2021] [Indexed: 12/19/2022] Open
Abstract
Inactivation technology for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is certainly a critical measure to mitigate the spread of coronavirus disease 2019 (COVID-19). A deep ultraviolet light-emitting diode (DUV-LED) would be a promising candidate to inactivate SARS-CoV-2, based on the well-known antiviral effects of DUV on microorganisms and viruses. However, due to variations in the inactivation effects across different viruses, quantitative evaluations of the inactivation profile of SARS-CoV-2 by DUV-LED irradiation need to be performed. In the present study, we quantify the irradiation dose of DUV-LED necessary to inactivate SARS-CoV-2. For this purpose, we determined the culture media suitable for the irradiation of SARS-CoV-2 and optimized the irradiation apparatus using commercially available DUV-LEDs that operate at a center wavelength of 265, 280, or 300 nm. Under these conditions, we successfully analyzed the relationship between SARS-CoV-2 infectivity and the irradiation dose of the DUV-LEDs at each wavelength without irrelevant biological effects. In conclusion, total doses of 1.8 mJ/cm2 for 265 nm, 3.0 mJ/cm2 for 280 nm, and 23 mJ/cm2 for 300 nm are required to inactivate 99.9% of SARS-CoV-2. Our results provide quantitative antiviral effects of DUV irradiation on SARS-CoV-2, serving as basic knowledge of inactivation technologies against SARS-CoV-2.
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Affiliation(s)
- Takeo Minamikawa
- Department of Post-LED Photonics Research, Institute of Post-LED Photonics, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan.
- Department of Mechanical Science, Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan.
- PRESTO, Japan Science and Technology Agency (JST), 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan.
- Research Cluster on "Multi-Scale Vibrational Microscopy for Comprehensive Diagnosis and Treatment of Cancer", Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan.
| | - Takaaki Koma
- Department of Microbiology, Graduate School of Biomedical Sciences, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Akihiro Suzuki
- Department of Post-LED Photonics Research, Institute of Post-LED Photonics, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Takahiko Mizuno
- Department of Post-LED Photonics Research, Institute of Post-LED Photonics, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Kentaro Nagamatsu
- Department of Post-LED Photonics Research, Institute of Post-LED Photonics, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
- Department of Electrical and Electronic Engineering, Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Hideki Arimochi
- Department of Immunology and Parasitology, Graduate School of Biomedical Sciences, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Koichiro Tsuchiya
- Department of Medical Pharmacology, Graduate School of Biomedical Sciences, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Kaoru Matsuoka
- Department of Post-LED Photonics Research, Institute of Post-LED Photonics, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Takeshi Yasui
- Department of Post-LED Photonics Research, Institute of Post-LED Photonics, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
- Department of Mechanical Science, Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
- Research Cluster on "Multi-Scale Vibrational Microscopy for Comprehensive Diagnosis and Treatment of Cancer", Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Koji Yasutomo
- Department of Immunology and Parasitology, Graduate School of Biomedical Sciences, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
- Department of Interdisciplinary Researches for Medicine and Photonics, Institute of Post-LED Photonics, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
- Research Cluster On "Immunological Diseases", Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Masako Nomaguchi
- Department of Microbiology, Graduate School of Biomedical Sciences, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan.
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Arines J. Suitability of DIALux for designing UVC disinfection cabins. Appl Opt 2021; 60:1821-1826. [PMID: 33690269 DOI: 10.1364/ao.418371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 01/25/2021] [Indexed: 05/24/2023]
Abstract
During the present Sars-CoV-2 pandemic, there has been an increase in the development of UVC disinfection systems. Researchers and members of the lighting community shifted their interests to this new field to help develop systems for disinfecting facemasks and other small equipment. In this paper we show that it is possible to use DIALux to simulate the irradiance distribution provided by a lamp emitting in the UVC range. We will compare the results provided by DIALux with those obtained from Zemax OpticStudio in three different scenarios. We compared the minimum, maximum, and mean irradiance at the detection plane. The differences between the two software were less than 12%, 2%, and 6%, respectively. We also compared the contour maps of isoirradiance lines. We conclude that DIALux is well suited for UVC lighting design in the UVC range. We think that this finding will contribute to increasing the design and manufacturing of new UVC disinfection systems needed to fight against the Sars-CoV-2 pandemic.
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40
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Kitagawa H, Nomura T, Nazmul T, Omori K, Shigemoto N, Sakaguchi T, Ohge H. Effectiveness of 222-nm ultraviolet light on disinfecting SARS-CoV-2 surface contamination. Am J Infect Control 2021; 49:299-301. [PMID: 32896604 PMCID: PMC7473342 DOI: 10.1016/j.ajic.2020.08.022] [Citation(s) in RCA: 117] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 08/13/2020] [Accepted: 08/14/2020] [Indexed: 12/16/2022]
Abstract
Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), has emerged as a serious threat to human health worldwide. Efficient disinfection of surfaces contaminated with SARS-CoV-2 may help prevent its spread. This study aimed to investigate the in vitro efficacy of 222-nm far-ultraviolet light (UVC) on the disinfection of SARS-CoV-2 surface contamination. Methods We investigated the titer of SARS-CoV-2 after UV irradiation (0.1 mW/cm2) at 222 nm for 10-300 seconds using the 50% tissue culture infectious dose (TCID50). In addition, we used quantitative reverse transcription polymerase chain reaction to quantify SARS-CoV-2 RNA under the same conditions. Results One and 3 mJ/cm2 of 222-nm UVC irradiation (0.1 mW/cm2 for 10 and 30 seconds) resulted in 88.5 and 99.7% reduction of viable SARS-CoV-2 based on the TCID50 assay, respectively. In contrast, the copy number of SARS-CoV-2 RNA did not change after UVC irradiation even after a 5-minute irradiation. Conclusions This study shows the efficacy of 222-nm UVC irradiation against SARS-CoV-2 contamination in an in vitro experiment. Further evaluation of the safety and efficacy of 222-nm UVC irradiation in reducing the contamination of real-world surfaces and the potential transmission of SARS-CoV-2 is needed.
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Affiliation(s)
- Hiroki Kitagawa
- Project Research Center for Nosocomial Infectious Diseases, Hiroshima University, Hiroshima, Japan; Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan; Department of Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
| | - Toshihito Nomura
- Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan; Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Tanuza Nazmul
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Keitaro Omori
- Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan
| | - Norifumi Shigemoto
- Project Research Center for Nosocomial Infectious Diseases, Hiroshima University, Hiroshima, Japan; Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan; Department of Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan; Translational Research Center, Hiroshima University, Hiroshima, Japan
| | - Takemasa Sakaguchi
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Hiroki Ohge
- Project Research Center for Nosocomial Infectious Diseases, Hiroshima University, Hiroshima, Japan; Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan
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Venkatesulu BP, Lester S, Hsieh CE, Verma V, Sharon E, Ahmed M, Krishnan S. Low-Dose Radiation Therapy for COVID-19: Promises and Pitfalls. JNCI Cancer Spectr 2021; 5:pkaa103. [PMID: 33437924 PMCID: PMC7717342 DOI: 10.1093/jncics/pkaa103] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 12/24/2022] Open
Abstract
The coronavirus disease-2019 (COVID-19) pandemic caused by SARS-CoV-2 has exacted an enormous toll on healthcare systems worldwide. The cytokine storm that follows pulmonary infection is causally linked to respiratory compromise and mortality in the majority of patients. The sparsity of viable treatment options for this viral infection and the sequelae of pulmonary complications have fueled the quest for new therapeutic considerations. One such option, the long-forgotten idea of using low-dose radiation therapy, has recently found renewed interest in many academic centers. We outline the scientific and logistical rationale for consideration of this option and the mechanistic underpinnings of any potential therapeutic value, particularly as viewed from an immunological perspective. We also discuss the preliminary and/or published results of prospective trials examining low-dose radiation therapy for COVID-19.
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Affiliation(s)
- Bhanu P Venkatesulu
- Department of Radiation Oncology, Loyola University Stritch School of Medicine, Chicago, IL, USA
| | - Scott Lester
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA
| | - Cheng-En Hsieh
- Department of Immunology, MD Anderson Cancer Center, Houston, TX, USA
| | - Vivek Verma
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX, USA
| | - Elad Sharon
- Radiation Research Program, Division Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD, USA
| | - Mansoor Ahmed
- Cancer Therapy Evaluation Program, Division Cancer Treatment and Diagnosis National Cancer Institute, Bethesda, MD, USA
| | - Sunil Krishnan
- Department of Radiation Oncology, Mayo Clinic Florida, Jacksonville, FL, USA
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Muñoz M, Comtois-Bona M, Cortes D, Cimenci CE, Du Q, Thompson C, Figueroa JD, Franklin V, Liu P, Alarcon EI. Integrated photothermal decontamination device for N95 respirators. Sci Rep 2021; 11:1822. [PMID: 33469049 PMCID: PMC7815715 DOI: 10.1038/s41598-020-80908-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/24/2020] [Indexed: 02/07/2023] Open
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for the COVID-19 global pandemic has infected over 25 million people worldwide and resulted in the death of millions. The COVID-19 pandemic has also resulted in a shortage of personal protective equipment (PPE) in many regions around the world, particularly in middle- and low-income countries. The shortages of PPE, such as N95 respirators, is something that will persist until an effective vaccine is made available. Thus, devices that while being easy to operate can also be rapidly deployed in health centers, and long-term residences without the need for major structural overhaul are instrumental to sustainably use N95 respirators. In this report, we present the design and validation of a decontamination device that combines UV-C & B irradiation with mild-temperature treatment. The device can decontaminate up to 20 masks in a cycle of < 30 min. The decontamination process did not damage or reduce the filtering capacity of the masks. Further, the efficacy of the device to eliminate microbes and viruses from the masks was also evaluated. The photothermal treatment of our device was capable of eradicating > 99.9999% of the bacteria and > 99.99% of the virus tested.
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Affiliation(s)
- Marcelo Muñoz
- Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y4W7, Canada
- Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, 451 Smyth Road, Ottawa, ON, K1H8M5, Canada
| | - Maxime Comtois-Bona
- Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y4W7, Canada
- Biomedical Mechanical Engineering, University of Ottawa, 800 King Edward Ave, Ottawa, ON, K1N6N5, Canada
| | - David Cortes
- Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y4W7, Canada
- Biomedical Mechanical Engineering, University of Ottawa, 800 King Edward Ave, Ottawa, ON, K1N6N5, Canada
| | - Cagla Eren Cimenci
- Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y4W7, Canada
- Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, K1H8M5, Canada
| | - Qiujiang Du
- Cardiac Function Laboratory, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y4W7, Canada
| | - Collin Thompson
- Occupational Health, Safety and Biosafety, University of Ottawa Heart Institute, 40 Ruskin street, Ottawa, ON, K1Y4W7, Canada
| | - Juan David Figueroa
- Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y4W7, Canada
| | - Vivian Franklin
- Laboratory Research Resources, Office of Research Services, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y4W7, Canada
| | - Peter Liu
- Cardiac Function Laboratory, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y4W7, Canada
| | - Emilio I Alarcon
- Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y4W7, Canada.
- Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, 451 Smyth Road, Ottawa, ON, K1H8M5, Canada.
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Abstract
With nearly every country combating the 2019 novel coronavirus (COVID-19), there is a need to understand how local environmental conditions may modify transmission. To date, quantifying seasonality of the disease has been limited by scarce data and the difficulty of isolating climatological variables from other drivers of transmission in observational studies. We combine a spatially resolved dataset of confirmed COVID-19 cases, composed of 3,235 regions across 173 countries, with local environmental conditions and a statistical approach developed to quantify causal effects of environmental conditions in observational data settings. We find that ultraviolet (UV) radiation has a statistically significant effect on daily COVID-19 growth rates: a SD increase in UV lowers the daily growth rate of COVID-19 cases by ∼1 percentage point over the subsequent 2.5 wk, relative to an average in-sample growth rate of 13.2%. The time pattern of lagged effects peaks 9 to 11 d after UV exposure, consistent with the combined timescale of incubation, testing, and reporting. Cumulative effects of temperature and humidity are not statistically significant. Simulations illustrate how seasonal changes in UV have influenced regional patterns of COVID-19 growth rates from January to June, indicating that UV has a substantially smaller effect on the spread of the disease than social distancing policies. Furthermore, total COVID-19 seasonality has indeterminate sign for most regions during this period due to uncertain effects of other environmental variables. Our findings indicate UV exposure influences COVID-19 cases, but a comprehensive understanding of seasonality awaits further analysis.
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Affiliation(s)
- Tamma Carleton
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106-3151
| | - Jules Cornetet
- Département de Sciences Sociales, École Normale Supérieure Paris-Saclay, 94235 Cachan Cedex, France
| | - Peter Huybers
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138
| | - Kyle C Meng
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106-3151;
- Department of Economics, University of California, Santa Barbara, CA 93106-3151
- National Bureau of Economic Research, Cambridge, MA 02138
| | - Jonathan Proctor
- Center for the Environment, Harvard University, Cambridge, MA 02138
- Data Science Initiative, Harvard University, Cambridge, MA 02138
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Weaver DT, McElvany BD, Gopalakrishnan V, Card KJ, Crozier D, Dhawan A, Dinh MN, Dolson E, Farrokhian N, Hitomi M, Ho E, Jagdish T, King ES, Cadnum JL, Donskey CJ, Krishnan N, Kuzmin G, Li J, Maltas J, Mo J, Pelesko J, Scarborough JA, Sedor G, Tian E, An GC, Diehl SA, Scott JG. UV decontamination of personal protective equipment with idle laboratory biosafety cabinets during the COVID-19 pandemic. PLoS One 2021; 16:e0241734. [PMID: 34310599 DOI: 10.1101/2020.03.25.20043489] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 06/19/2021] [Indexed: 05/21/2023] Open
Abstract
Personal protective equipment (PPE) is crucially important to the safety of both patients and medical personnel, particularly in the event of an infectious pandemic. As the incidence of Coronavirus Disease 2019 (COVID-19) increases exponentially in the United States and many parts of the world, healthcare provider demand for these necessities is currently outpacing supply. In the midst of the current pandemic, there has been a concerted effort to identify viable ways to conserve PPE, including decontamination after use. In this study, we outline a procedure by which PPE may be decontaminated using ultraviolet (UV) radiation in biosafety cabinets (BSCs), a common element of many academic, public health, and hospital laboratories. According to the literature, effective decontamination of N95 respirator masks or surgical masks requires UV-C doses of greater than 1 Jcm-2, which was achieved after 4.3 hours per side when placing the N95 at the bottom of the BSCs tested in this study. We then demonstrated complete inactivation of the human coronavirus NL63 on N95 mask material after 15 minutes of UV-C exposure at 61 cm (232 μWcm-2). Our results provide support to healthcare organizations looking for methods to extend their reserves of PPE.
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Affiliation(s)
- Davis T Weaver
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Benjamin D McElvany
- University of Vermont Medical Center, Burlington, VT, United States of America
| | - Vishhvaan Gopalakrishnan
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Kyle J Card
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- Michigan State University, East Lansing, MI, United States of America
| | - Dena Crozier
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Andrew Dhawan
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- Cleveland Clinic, Division of Neurology, Cleveland, OH, United States of America
| | - Mina N Dinh
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Emily Dolson
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Nathan Farrokhian
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Masahiro Hitomi
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Emily Ho
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Tanush Jagdish
- Dana Farber Cancer Insitute, Harvard University, Boston, MA, United States of America
| | - Eshan S King
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | | | | | - Nikhil Krishnan
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Gleb Kuzmin
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Ju Li
- Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Jeff Maltas
- University of Michigan, Ann Arbor, MI, United States of America
| | | | - Julia Pelesko
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Jessica A Scarborough
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Geoff Sedor
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Enze Tian
- Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Gary C An
- University of Vermont Medical Center, Burlington, VT, United States of America
| | - Sean A Diehl
- University of Vermont Medical Center, Burlington, VT, United States of America
| | - Jacob G Scott
- Cleveland Clinic Lerner Research Institute and Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
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45
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Khaiboullina S, Uppal T, Dhabarde N, Subramanian VR, Verma SC. Inactivation of Human Coronavirus by Titania Nanoparticle Coatings and UVC Radiation: Throwing Light on SARS-CoV-2. Viruses 2020. [PMID: 33374195 DOI: 10.1101/2020.08.25.265223] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023] Open
Abstract
The newly identified pathogenic human coronavirus, SARS-CoV-2, led to an atypical pneumonia-like severe acute respiratory syndrome (SARS) outbreak called coronavirus disease 2019 (abbreviated as COVID-19). Currently, nearly 77 million cases have been confirmed worldwide with the highest numbers of COVID-19 cases in the United States. Individuals are getting vaccinated with recently approved vaccines, which are highly protective in suppressing COVID-19 symptoms but there will be a long way before the majority of individuals get vaccinated. In the meantime, safety precautions and effective disease control strategies appear to be vital for preventing the virus spread in public places. Due to the longevity of the virus on smooth surfaces, photocatalytic properties of "self-disinfecting/cleaning" surfaces appear to be a promising tool to help guide disinfection policies for controlling SARS-CoV-2 spread in high-traffic areas such as hospitals, grocery stores, airports, schools, and stadiums. Here, we explored the photocatalytic properties of nanosized TiO2 (TNPs) as induced by the UV radiation, towards virus deactivation. Our preliminary results using a close genetic relative of SAR-CoV-2, HCoV-NL63, showed the virucidal efficacy of photoactive TNPs deposited on glass coverslips, as examined by quantitative RT-qPCR and virus infectivity assays. Efforts to extrapolate the underlying concepts described in this study to SARS-CoV-2 are currently underway.
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Affiliation(s)
- Svetlana Khaiboullina
- Department of Microbiology and Immunology, Reno School of Medicine, University of Nevada, 1664 N Virginia Street, Reno, NV 89557, USA
| | - Timsy Uppal
- Department of Microbiology and Immunology, Reno School of Medicine, University of Nevada, 1664 N Virginia Street, Reno, NV 89557, USA
| | - Nikhil Dhabarde
- Chemical and Materials Engineering Department, University of Nevada, LME 309, MS 388, Reno, NV 89557, USA
| | - Vaidyanathan Ravi Subramanian
- Chemical and Materials Engineering Department, University of Nevada, LME 309, MS 388, Reno, NV 89557, USA
- GenNEXT Materials and Technologies, LLC., Reno, NV 89511, USA
| | - Subhash C Verma
- Department of Microbiology and Immunology, Reno School of Medicine, University of Nevada, 1664 N Virginia Street, Reno, NV 89557, USA
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46
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Khaiboullina S, Uppal T, Dhabarde N, Subramanian VR, Verma SC. Inactivation of Human Coronavirus by Titania Nanoparticle Coatings and UVC Radiation: Throwing Light on SARS-CoV-2. Viruses 2020; 13:E19. [PMID: 33374195 PMCID: PMC7824386 DOI: 10.3390/v13010019] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 12/17/2020] [Accepted: 12/19/2020] [Indexed: 12/27/2022] Open
Abstract
The newly identified pathogenic human coronavirus, SARS-CoV-2, led to an atypical pneumonia-like severe acute respiratory syndrome (SARS) outbreak called coronavirus disease 2019 (abbreviated as COVID-19). Currently, nearly 77 million cases have been confirmed worldwide with the highest numbers of COVID-19 cases in the United States. Individuals are getting vaccinated with recently approved vaccines, which are highly protective in suppressing COVID-19 symptoms but there will be a long way before the majority of individuals get vaccinated. In the meantime, safety precautions and effective disease control strategies appear to be vital for preventing the virus spread in public places. Due to the longevity of the virus on smooth surfaces, photocatalytic properties of "self-disinfecting/cleaning" surfaces appear to be a promising tool to help guide disinfection policies for controlling SARS-CoV-2 spread in high-traffic areas such as hospitals, grocery stores, airports, schools, and stadiums. Here, we explored the photocatalytic properties of nanosized TiO2 (TNPs) as induced by the UV radiation, towards virus deactivation. Our preliminary results using a close genetic relative of SAR-CoV-2, HCoV-NL63, showed the virucidal efficacy of photoactive TNPs deposited on glass coverslips, as examined by quantitative RT-qPCR and virus infectivity assays. Efforts to extrapolate the underlying concepts described in this study to SARS-CoV-2 are currently underway.
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Affiliation(s)
- Svetlana Khaiboullina
- Department of Microbiology and Immunology, Reno School of Medicine, University of Nevada, 1664 N Virginia Street, Reno, NV 89557, USA; (S.K.); (T.U.)
| | - Timsy Uppal
- Department of Microbiology and Immunology, Reno School of Medicine, University of Nevada, 1664 N Virginia Street, Reno, NV 89557, USA; (S.K.); (T.U.)
| | - Nikhil Dhabarde
- Chemical and Materials Engineering Department, University of Nevada, LME 309, MS 388, Reno, NV 89557, USA;
| | - Vaidyanathan Ravi Subramanian
- Chemical and Materials Engineering Department, University of Nevada, LME 309, MS 388, Reno, NV 89557, USA;
- GenNEXT Materials and Technologies, LLC., Reno, NV 89511, USA
| | - Subhash C. Verma
- Department of Microbiology and Immunology, Reno School of Medicine, University of Nevada, 1664 N Virginia Street, Reno, NV 89557, USA; (S.K.); (T.U.)
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47
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Fervers P, Kottlors J, Zopfs D, Bremm J, Maintz D, Safarov O, Tritt S, Abdullayev N, Persigehl T. Calcification of the thoracic aorta on low-dose chest CT predicts severe COVID-19. PLoS One 2020; 15:e0244267. [PMID: 33362199 PMCID: PMC7757863 DOI: 10.1371/journal.pone.0244267] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 12/08/2020] [Indexed: 12/29/2022] Open
Abstract
Background Cardiovascular comorbidity anticipates poor prognosis of SARS-CoV-2 disease (COVID-19) and correlates with the systemic atherosclerotic transformation of the arterial vessels. The amount of aortic wall calcification (AWC) can be estimated on low-dose chest CT. We suggest quantification of AWC on the low-dose chest CT, which is initially performed for the diagnosis of COVID-19, to screen for patients at risk of severe COVID-19. Methods Seventy consecutive patients (46 in center 1, 24 in center 2) with parallel low-dose chest CT and positive RT-PCR for SARS-CoV-2 were included in our multi-center, multi-vendor study. The outcome was rated moderate (no hospitalization, hospitalization) and severe (ICU, tracheal intubation, death), the latter implying a requirement for intensive care treatment. The amount of AWC was quantified with the CT vendor's software. Results Of 70 included patients, 38 developed a moderate, and 32 a severe COVID-19. The average volume of AWC was significantly higher throughout the subgroup with severe COVID-19, when compared to moderate cases (771.7 mm3 (Q1 = 49.8 mm3, Q3 = 3065.5 mm3) vs. 0 mm3 (Q1 = 0 mm3, Q3 = 57.3 mm3)). Within multivariate regression analysis, including AWC, patient age and sex, as well as a cardiovascular comorbidity score, the volume of AWC was the only significant regressor for severe COVID-19 (p = 0.004). For AWC > 3000 mm3, the logistic regression predicts risk for a severe progression of 0.78. If there are no visually detectable AWC risk for severe progression is 0.13, only. Conclusion AWC seems to be an independent biomarker for the prediction of severe progression and intensive care treatment of COVID-19 already at the time of patient admission to the hospital; verification in a larger multi-center, multi-vendor study is desired.
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Affiliation(s)
- Philipp Fervers
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
- * E-mail:
| | - Jonathan Kottlors
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - David Zopfs
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Johannes Bremm
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - David Maintz
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Orkhan Safarov
- Department of Radiology, Helios Dr. Horst Schmidt Kliniken Wiesbaden, Wiesbaden, Germany
| | - Stephanie Tritt
- Department of Radiology, Helios Dr. Horst Schmidt Kliniken Wiesbaden, Wiesbaden, Germany
| | - Nuran Abdullayev
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Thorsten Persigehl
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
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Kumar A, Kasloff SB, Leung A, Cutts T, Strong JE, Hills K, Gu FX, Chen P, Vazquez-Grande G, Rush B, Lother S, Malo K, Zarychanski R, Krishnan J. Decontamination of N95 masks for re-use employing 7 widely available sterilization methods. PLoS One 2020; 15:e0243965. [PMID: 33326504 PMCID: PMC7744046 DOI: 10.1371/journal.pone.0243965] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 12/01/2020] [Indexed: 11/19/2022] Open
Abstract
The response to the COVID-19 epidemic is generating severe shortages of personal protective equipment around the world. In particular, the supply of N95 respirator masks has become severely depleted, with supplies having to be rationed and health care workers having to use masks for prolonged periods in many countries. We sought to test the ability of 7 different decontamination methods: autoclave treatment, ethylene oxide gassing (ETO), low temperature hydrogen peroxide gas plasma (LT-HPGP) treatment, vaporous hydrogen peroxide (VHP) exposure, peracetic acid dry fogging (PAF), ultraviolet C irradiation (UVCI) and moist heat (MH) treatment to decontaminate a variety of different N95 masks following experimental contamination with SARS-CoV-2 or vesicular stomatitis virus as a surrogate. In addition, we sought to determine whether masks would tolerate repeated cycles of decontamination while maintaining structural and functional integrity. All methods except for UVCI were effective in total elimination of viable virus from treated masks. We found that all respirator masks tolerated at least one cycle of all treatment modalities without structural or functional deterioration as assessed by fit testing; filtration efficiency testing results were mostly similar except that a single cycle of LT-HPGP was associated with failures in 3 of 6 masks assessed. VHP, PAF, UVCI, and MH were associated with preserved mask integrity to a minimum of 10 cycles by both fit and filtration testing. A similar result was shown with ethylene oxide gassing to the maximum 3 cycles tested. Pleated, layered non-woven fabric N95 masks retained integrity in fit testing for at least 10 cycles of autoclaving but the molded N95 masks failed after 1 cycle; filtration testing however was intact to 5 cycles for all masks. The successful application of autoclaving for layered, pleated masks may be of particular use to institutions globally due to the virtually universal accessibility of autoclaves in health care settings. Given the ability to modify widely available heating cabinets on hospital wards in well-resourced settings, the application of moist heat may allow local processing of N95 masks.
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Affiliation(s)
- Anand Kumar
- Sections of Critical Care Medicine and Infectious Diseases, Departments of Medicine, Medical Microbiology and Pharmacology, University of Manitoba, Winnipeg, Canada
| | - Samantha B. Kasloff
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Anders Leung
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Todd Cutts
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - James E. Strong
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Kevin Hills
- National Centre for Foreign Animal Diseases, Canadian Food Inspection Agency, Winnipeg, Canada
| | | | - Paul Chen
- University of Toronto, Toronto, Canada
| | - Gloria Vazquez-Grande
- Section of Critical Care Medicine, Department of Medicine, University of Manitoba, Winnipeg, Canada
| | - Barret Rush
- Section of Critical Care Medicine, Department of Medicine, University of Manitoba, Winnipeg, Canada
| | - Sylvain Lother
- Section of Critical Care Medicine, Department of Medicine, University of Manitoba, Winnipeg, Canada
| | - Kimberly Malo
- Occupational & Environmental Safety and Health, Winnipeg Regional Health Authority, Winnipeg, Canada
| | - Ryan Zarychanski
- Sections of Critical Care and Hematology, Departments of Medicine and Community Health Sciences, University of Manitoba, Winnipeg, Canada
| | - Jay Krishnan
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
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49
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Monge F, Jagadesan P, Bondu V, Donabedian PL, Ista L, Chi EY, Schanze KS, Whitten DG, Kell AM. Highly Effective Inactivation of SARS-CoV-2 by Conjugated Polymers and Oligomers. ACS Appl Mater Interfaces 2020; 12:55688-55695. [PMID: 33267577 PMCID: PMC7724758 DOI: 10.1021/acsami.0c17445] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 11/18/2020] [Indexed: 05/08/2023]
Abstract
In the present study, we examined the inactivation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by synthetic conjugated polymers and oligomers developed in our laboratories as antimicrobials for bacteria, fungi, and nonenveloped viruses. The results show highly effective light-induced inactivation with several of these oligomers and polymers including irradiation with near-UV and visible light. In the best case, one oligomer induced a 5-log reduction in pfu/mL within 10 min. In general, the oligomers are more active than the polymers; however, the polymers are active with longer wavelength visible irradiation. Although not studied quantitatively, the results show that in the presence of the agents at concentrations similar to those used in the light studies, there is essentially no dark inactivation of the virus. Because three of the five materials/compounds examined are quaternary ammonium derivatives, this study indicates that conventional quaternary ammonium antimicrobials may not be active against SARS-CoV-2. Our results suggest several applications involving the incorporation of these materials in wipes, sprays, masks, and clothing and other personal protection equipment that can be useful in preventing infections and the spreading of this deadly virus and future outbreaks from similar viruses.
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Affiliation(s)
- Florencia
A. Monge
- Center
for Biomedical Engineering, University of
New Mexico, Albuquerque 87131-0001, New Mexico, United States
- Biomedical
Engineering Graduate Program, University
of New Mexico, Albuquerque 87131-0001, New Mexico, United States
| | - Pradeepkumar Jagadesan
- Department
of Chemistry, University of Texas at San
Antonio, San Antonio 78249-1644, Texas, United States
| | - Virginie Bondu
- Department
of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque 87131-0001, New Mexico, United States
| | - Patrick L. Donabedian
- Center
for Biomedical Engineering, University of
New Mexico, Albuquerque 87131-0001, New Mexico, United States
- Nanoscience
and Microsystems Engineering Graduate Program, University of New Mexico, Albuquerque 87131-0001, New Mexico, United States
| | - Linnea Ista
- Center
for Biomedical Engineering, University of
New Mexico, Albuquerque 87131-0001, New Mexico, United States
- Department
of Chemical and Biological Engineering, University of New Mexico, Albuquerque 87131, New Mexico, United States
| | - Eva Y. Chi
- Center
for Biomedical Engineering, University of
New Mexico, Albuquerque 87131-0001, New Mexico, United States
- Department
of Chemical and Biological Engineering, University of New Mexico, Albuquerque 87131, New Mexico, United States
| | - Kirk S. Schanze
- Department
of Chemistry, University of Texas at San
Antonio, San Antonio 78249-1644, Texas, United States
| | - David G. Whitten
- Center
for Biomedical Engineering, University of
New Mexico, Albuquerque 87131-0001, New Mexico, United States
- Department
of Chemical and Biological Engineering, University of New Mexico, Albuquerque 87131, New Mexico, United States
- Department
of Chemistry and Chemical Biology, University
of New Mexico, Albuquerque 87131-0001, New Mexico, United States
| | - Alison M. Kell
- Department
of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque 87131-0001, New Mexico, United States
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50
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Buchan AG, Yang L, Atkinson KD. Predicting airborne coronavirus inactivation by far-UVC in populated rooms using a high-fidelity coupled radiation-CFD model. Sci Rep 2020; 10:19659. [PMID: 33184316 PMCID: PMC7665067 DOI: 10.1038/s41598-020-76597-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 10/25/2020] [Indexed: 01/05/2023] Open
Abstract
There are increased risks of contracting COVID-19 in hospitals and long-term care facilities, particularly for vulnerable groups. In these environments aerosolised coronavirus released through breathing increases the chance of spreading the disease. To reduce aerosol transmissions, the use of low dose far-UVC lighting to disinfect in-room air has been proposed. Unlike typical UVC, which has been used to kill microorganisms for decades but is carcinogenic and cataractogenic, recent evidence has shown that far-UVC is safe to use around humans. A high-fidelity, fully-coupled radiation transport and fluid dynamics model has been developed to quantify disinfection rates within a typical ventilated room. The model shows that disinfection rates are increased by a further 50-85% when using far-UVC within currently recommended exposure levels compared to the room's ventilation alone. With these magnitudes of reduction, far-UVC lighting could be employed to mitigate SARS-CoV-2 transmission before the onset of future waves, or the start of winter when risks of infection are higher. This is particularly significant in poorly-ventilated spaces where other means of reduction are not practical, in addition social distancing can be reduced without increasing the risk.
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Affiliation(s)
- Andrew G Buchan
- School of Engineering and Materials Science, Queen Mary University of London, London, E1 4NS, UK
| | - Liang Yang
- School of Water, Energy and Environment (SWEE), Cranfield University, Bedford, MK43 0AL, UK
| | - Kirk D Atkinson
- Faculty of Energy Systems and Nuclear Science, Ontario Tech University, Oshawa, Ontario, L1G 0C5, Canada.
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