1
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Raza S, Wdowiak M, Paczesny J. An Overview of Diverse Strategies To Inactivate Enterobacteriaceae-Targeting Bacteriophages. EcoSal Plus 2023; 11:eesp00192022. [PMID: 36651738 DOI: 10.1128/ecosalplus.esp-0019-2022] [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: 09/21/2022] [Accepted: 12/20/2022] [Indexed: 01/19/2023]
Abstract
Bacteriophages are viruses that infect bacteria and thus threaten industrial processes relying on the production executed by bacterial cells. Industries bear huge economic losses due to such recurring and resilient infections. Depending on the specificity of the process, there is a need for appropriate methods of bacteriophage inactivation, with an emphasis on being inexpensive and high efficiency. In this review, we summarize the reports on antiphagents, i.e., antibacteriophage agents on inactivation of bacteriophages. We focused on bacteriophages targeting the representatives of the Enterobacteriaceae family, as its representative, Escherichia coli, is most commonly used in the bio-industry. The review is divided into sections dealing with bacteriophage inactivation by physical factors, chemical factors, and nanotechnology-based solutions.
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Affiliation(s)
- Sada Raza
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
| | - Mateusz Wdowiak
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
| | - Jan Paczesny
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
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2
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Sinclair LG, Ilieva Z, Morris G, Anderson JG, MacGregor SJ, Maclean M. Viricidal Efficacy of a 405-nm Environmental Decontamination System for Inactivation of Bacteriophage Phi6: Surrogate for SARS-CoV-2. Photochem Photobiol 2023; 99:1493-1500. [PMID: 36872097 PMCID: PMC10952546 DOI: 10.1111/php.13798] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 11/01/2022] [Accepted: 03/01/2023] [Indexed: 03/07/2023]
Abstract
The highly transmittable nature of SARS-CoV-2 has increased the necessity for novel strategies to safely decontaminate public areas. This study investigates the efficacy of a low irradiance 405-nm light environmental decontamination system for the inactivation of bacteriophage phi6 as a surrogate for SARS-CoV-2. Bacteriophage phi6 was exposed to increasing doses of low irradiance (~0.5 mW cm-2 ) 405-nm light while suspended in SM buffer and artificial human saliva at low (~103-4 PFU mL-1 ) and high (~107-8 PFU mL-1 ) seeding densities, to determine system efficacy for SARS-CoV-2 inactivation and establish the influence of biologically relevant suspension media on viral susceptibility. Complete/near-complete (≥99.4%) inactivation was demonstrated in all cases, with significantly enhanced reductions observed in biologically relevant media (P < 0.05). Doses of 43.2 and 172.8 J cm-2 were required to achieve ~3 log10 reductions at low density, and 97.2 and 259.2 J cm-2 achieved ~6 log10 reductions at high density, in saliva and SM buffer, respectively: 2.6-4 times less dose was required when suspended in saliva compared to SM buffer. Comparative exposure to higher irradiance (~50 mW cm-2 ) 405-nm light indicated that, on a per unit dose basis, 0.5 mW cm-2 treatments were capable of achieving up to 5.8 greater log10 reductions with up to 28-fold greater germicidal efficiency than that of 50 mW cm-2 treatments. These findings establish the efficacy of low irradiance 405-nm light systems for inactivation of a SARS-CoV-2 surrogate and demonstrate the significant enhancement in susceptibility when suspended in saliva, which is a major vector in COVID-19 transmission.
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Affiliation(s)
- Lucy G. Sinclair
- Department of Electronic & Electrical Engineering, The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST)University of StrathclydeGlasgowUK
| | - Zornitsa Ilieva
- Department of Biomedical EngineeringUniversity of StrathclydeGlasgowUK
| | - Georgina Morris
- Department of Biomedical EngineeringUniversity of StrathclydeGlasgowUK
| | - John G. Anderson
- Department of Electronic & Electrical Engineering, The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST)University of StrathclydeGlasgowUK
| | - Scott J. MacGregor
- Department of Electronic & Electrical Engineering, The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST)University of StrathclydeGlasgowUK
| | - Michelle Maclean
- Department of Electronic & Electrical Engineering, The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST)University of StrathclydeGlasgowUK
- Department of Biomedical EngineeringUniversity of StrathclydeGlasgowUK
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3
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Hamilton AN, Chandran S, Baker CA, Gibson KE. Surface Inactivation of a SARS-CoV-2 Surrogate with Hypochlorous Acid is Impacted by Surface Type, Contact Time, Inoculum Matrix, and Concentration. Food Environ Virol 2023; 15:116-122. [PMID: 36680664 PMCID: PMC9862229 DOI: 10.1007/s12560-023-09549-0] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 01/13/2023] [Indexed: 06/13/2023]
Abstract
Indirect contact with contaminated surfaces is a potential transmission route for COVID-19. Therefore, it is necessary to investigate convenient and inexpensive surface sanitization methods, such as HOCl, against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 surrogate, Phi6 (~ 7 log PFU/mL), was prepared in artificial saliva and tripartite matrices, spot inoculated on coupons of either stainless steel or vinyl, and allowed to dry. The coupons were sprayed with either 500 ppm or 1000 ppm HOCl, and remained on the surface for 0 s (control), 5 s, 30 s, or 60 s. Samples were enumerated via the double agar overlay assay. Statistical analysis was completed in R using a generalized linear model with Quasipoisson error approximations. Time, concentration, surface type, and inoculum matrix were all significant contributors to log reduction at P = 0.05. Significant three-way interactions were observed for 1000 ppm, vinyl, and 60 s (P = 0.03) and 1000 ppm, tripartite, and 60 s (P = 0.0121). A significant two-way interaction between vinyl and 60 s was also observed (P = 0.0168). Overall, increased HOCl concentration and exposure time led to increased Phi6 reduction. Notably, the highest estimated mean log reduction was 3.31 (95% CI 3.14, 3.49) for stainless steel at 60 s and 1000 ppm HOCl in artificial saliva, indicating that this method of sanitization may not adequately reduce enveloped viruses to below infective thresholds.
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Affiliation(s)
- Allyson N Hamilton
- Department of Food Science, Center for Food Safety, University of Arkansas System Division of Agriculture, 1371 West Altheimer Dr., Fayetteville, AR, 72704, USA
| | - Sahaana Chandran
- Department of Food Science, Center for Food Safety, University of Arkansas System Division of Agriculture, 1371 West Altheimer Dr., Fayetteville, AR, 72704, USA
| | - Christopher A Baker
- Department of Food Science, Center for Food Safety, University of Arkansas System Division of Agriculture, 1371 West Altheimer Dr., Fayetteville, AR, 72704, USA
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, 5001 Campus Drive, College Park, MD, 20740, USA
| | - Kristen E Gibson
- Department of Food Science, Center for Food Safety, University of Arkansas System Division of Agriculture, 1371 West Altheimer Dr., Fayetteville, AR, 72704, USA.
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Bandara S, Oishi W, Kadoya SS, Sano D. Decay rate estimation of respiratory viruses in aerosols and on surfaces under different environmental conditions. Int J Hyg Environ Health 2023; 251:114187. [PMID: 37210848 DOI: 10.1016/j.ijheh.2023.114187] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/23/2023]
Abstract
Majority of the viral outbreaks are super-spreading events established within 2-10 h, dependent on a critical time interval for successful transmission between humans, which is governed by the decay rates of viruses. To evaluate the decay rates of respiratory viruses over a short span, we calculated their decay rate values for various surfaces and aerosols. We applied Bayesian regression and ridge regression and determined the best estimation for respiratory viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), severe acute respiratory syndrome coronavirus (SARS-CoV), middle east respiratory syndrome coronavirus (MERS-CoV), influenza viruses, and respiratory syncytial virus (RSV); the decay rate values in aerosols for these viruses were 4.83 ± 5.70, 0.40 ± 0.24, 0.11 ± 0.04, 2.43 ± 5.94, and 1.00 ± 0.50 h-1, respectively. The highest decay rate values for each virus type differed according to the surface type. According to the model performance criteria, the Bayesian regression model was better for SARS-CoV-2 and influenza viruses, whereas ridge regression was better for SARS-CoV and MERS-CoV. A simulation using a better estimation will help us find effective non-pharmaceutical interventions to control virus transmissions.
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Affiliation(s)
- Sewwandi Bandara
- Department of Frontier Science for Advanced Environment, Graduate School of Environment Studies, Tohoku University, Sendai, Miyagi, 980-8572, Japan
| | - Wakana Oishi
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Sendai, Miyagi, 980-8579, Japan
| | - Syun-Suke Kadoya
- Department of Urban Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8654, Japan
| | - Daisuke Sano
- Department of Frontier Science for Advanced Environment, Graduate School of Environment Studies, Tohoku University, Sendai, Miyagi, 980-8572, Japan; Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Sendai, Miyagi, 980-8579, Japan.
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5
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Karczewska M, Strzelecki P, Szalewska-Pałasz A, Nowicki D. How to Tackle Bacteriophages: The Review of Approaches with Mechanistic Insight. Int J Mol Sci 2023; 24:ijms24054447. [PMID: 36901878 PMCID: PMC10003480 DOI: 10.3390/ijms24054447] [Citation(s) in RCA: 4] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/21/2023] [Accepted: 02/22/2023] [Indexed: 02/26/2023] Open
Abstract
Bacteriophage-based applications have a renaissance today, increasingly marking their use in industry, medicine, food processing, biotechnology, and more. However, phages are considered resistant to various harsh environmental conditions; besides, they are characterized by high intra-group variability. Phage-related contaminations may therefore pose new challenges in the future due to the wider use of phages in industry and health care. Therefore, in this review, we summarize the current knowledge of bacteriophage disinfection methods, as well as highlight new technologies and approaches. We discuss the need for systematic solutions to improve bacteriophage control, taking into account their structural and environmental diversity.
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Affiliation(s)
- Monika Karczewska
- Department of Bacterial Molecular Genetics, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
| | - Patryk Strzelecki
- Department of Bacterial Molecular Genetics, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS, UMR7504, 23 rue du Loess, CEDEX 2, F-67034 Strasbourg, France
| | - Agnieszka Szalewska-Pałasz
- Department of Bacterial Molecular Genetics, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
| | - Dariusz Nowicki
- Department of Bacterial Molecular Genetics, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
- Correspondence: ; Tel.: +48-58-523-6065
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6
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Sanmark E, Kuula J, Laitinen S, Oksanen LMAH, Bamford DH, Atanasova NS. Safe use of PHI6 IN the experimental studies. Heliyon 2023; 9:e13565. [PMID: 36879750 PMCID: PMC9984441 DOI: 10.1016/j.heliyon.2023.e13565] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 02/02/2023] [Accepted: 02/02/2023] [Indexed: 02/09/2023] Open
Abstract
Surrogate viruses theoretically provide an opportunity to study the viral spread in an indoor environment, a highly needed understanding during the pandemic, in a safe manner to humans and the environment. However, the safety of surrogate viruses for humans as an aerosol at high concentrations has not been established. In this study, Phi6 surrogate was aerosolized at high concentration (Particulate matter2.5: ∼1018 μg m-3) in the studied indoor space. Participants were closely followed for any symptoms. We measured the bacterial endotoxin concentration of the virus solution used for aerosolization as well as the concentration in the room air containing the aerosolized viruses. In addition, we measured how the bacterial endotoxin concentration of the sample was affected by different traditional virus purification procedures. Despite the purification, bacterial endotoxin concentration of the Phi6 was high (350 EU/ml in solution used for aerosols) with both (two) purification protocols. Bacterial endotoxins were also detected in aerosolized form, but below the occupational exposure limit of 90 EU/m3. Despite these concerns, no symptoms were observed in exposed humans when they were using personal protective equipment. In the future, purification protocols should be developed to reduce associated bacterial endotoxin levels in enveloped bacterial virus specimens to ensure even safer research use of surrogate viruses.
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Affiliation(s)
- Enni Sanmark
- University of Helsinki, Faculty of Medicine, Helsinki, Finland.,Department of Otorhinolaryngology and Phoniatrics - Head and Neck Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Joel Kuula
- Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, Finland
| | - Sirpa Laitinen
- Finnish Institute of Occupational Health, Kuopio, Finland
| | - Lotta-Maria A H Oksanen
- University of Helsinki, Faculty of Medicine, Helsinki, Finland.,Department of Otorhinolaryngology and Phoniatrics - Head and Neck Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Dennis H Bamford
- Molecular and Integrative Biosciences Research Program, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Nina S Atanasova
- Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, Finland.,Molecular and Integrative Biosciences Research Program, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
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7
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Hessling M, Fehler N, Gierke A, Sicks B, Vatter P. Heat Inactivation of Influenza Viruses—Analysis of Published Data and Estimations for Required Decimal Reduction Times for Different Temperatures and Media. Microbiology Research 2022; 13:853-71. [DOI: 10.3390/microbiolres13040060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
(1) Background: Influenza is a viral infection that has claimed many millions of lives over the past 100 years, and there is always a risk that a new influenza virus will emerge and cause another pandemic. One way to reduce such a potential new influenza virus will be heat inactivation. The question in this study is how much the heat sensitivities of previous influenza viruses differ. If they are very similar, it is expected that a new influenza virus can be inactivated with the same heat parameters as previous influenza viruses. (2) Methods: Through a literature search, published heat inactivation results are compiled and analyzed using Arrhenius models and regression equations for decimal reduction times for different temperatures and media determined. (3) Results: There are about 50 studies on heat inactivation of human and avian influenza viruses so far, showing large differences in heat sensitivity of influenza viruses in different media. However, within a single medium the differences between viruses are rather small. (4) Conclusions: At a temperature of 60 °C, previous influenza viruses can be reduced by 4 or more orders of magnitude within approximately 30 min in almost all media, and this is likely to be true for a potential new influenza virus. Further studies, especially on human influenza viruses, would be desirable.
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8
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Derr TH, James MA, Kuny CV, Patel DR, Kandel PP, Field C, Beckman MD, Hockett KL, Bates MA, Sutton TC, Szpara ML. Aerosolized Hydrogen Peroxide Decontamination of N95 Respirators, with Fit-Testing and Viral Inactivation, Demonstrates Feasibility for Reuse during the COVID-19 Pandemic. mSphere 2022;:e0030322. [PMID: 36040048 DOI: 10.1128/msphere.00303-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
In response to the demand for N95 respirators by health care workers during the COVID-19 pandemic, we evaluated decontamination of N95 respirators using an aerosolized hydrogen peroxide (aHP) system. This system is designed to dispense a consistent atomized spray of aerosolized, 7% hydrogen peroxide (H2O2) solution over a treatment cycle. Multiple N95 respirator models were subjected to 10 or more cycles of respirator decontamination, with a select number periodically assessed for qualitative and quantitative fit testing. In parallel, we assessed the ability of aHP treatment to inactivate multiple viruses absorbed onto respirators, including phi6 bacteriophage, herpes simplex virus 1 (HSV-1), coxsackievirus B3 (CVB3), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). For pathogens transmitted via respiratory droplets and aerosols, it is critical to address respirator safety for reuse. This study provided experimental validation of an aHP treatment process that decontaminates the respirators while maintaining N95 function. External National Institute for Occupational Safety & Health (NIOSH) certification verified respirator structural integrity and filtration efficiency after 10 rounds of aHP treatment. Virus inactivation by aHP was comparable to the decontamination of commercial spore-based biological indicators. These data demonstrate that the aHP process is effective, with successful fit-testing of respirators after multiple aHP cycles, effective decontamination of multiple virus species, including SARS-CoV-2, successful decontamination of bacterial spores, and filtration efficiency maintained at or greater than 95%. While this study did not include extended or clinical use of N95 respirators between aHP cycles, these data provide proof of concept for aHP decontamination of N95 respirators before reuse in a crisis-capacity scenario. IMPORTANCE The COVID-19 pandemic led to unprecedented pressure on health care and research facilities to provide personal protective equipment. The respiratory nature of the SARS-CoV2 pathogen makes respirator facepieces a critical protective measure to limit inhalation of this virus. While respirator facepieces were designed for single use and disposal, the pandemic increased overall demand for N95 respirators, and corresponding manufacturing and supply chain limitations necessitated the safe reuse of respirators when necessary. In this study, we repurposed an aerosolized hydrogen peroxide (aHP) system that is regularly utilized to decontaminate materials in a biosafety level 3 (BSL3) facility, to develop a method for decontamination of N95 respirators. Results from viral inactivation, biological indicators, respirator fit testing, and filtration efficiency testing all indicated that the process was effective at rendering N95 respirators safe for reuse. This proof-of-concept study establishes baseline data for future testing of aHP in crisis-capacity respirator-reuse scenarios.
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9
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Sorci M, Fink TD, Sharma V, Singh S, Chen R, Arduini BL, Dovidenko K, Heldt CL, Palermo EF, Zha RH. Virucidal N95 Respirator Face Masks via Ultrathin Surface-Grafted Quaternary Ammonium Polymer Coatings. ACS Appl Mater Interfaces 2022; 14:25135-25146. [PMID: 35613701 PMCID: PMC9185690 DOI: 10.1021/acsami.2c04165] [Citation(s) in RCA: 3] [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] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
N95 respirator face masks serve as effective physical barriers against airborne virus transmission, especially in a hospital setting. However, conventional filtration materials, such as nonwoven polypropylene fibers, have no inherent virucidal activity, and thus, the risk of surface contamination increases with wear time. The ability of face masks to protect against infection can be likely improved by incorporating components that deactivate viruses on contact. We present a facile method for covalently attaching antiviral quaternary ammonium polymers to the fiber surfaces of nonwoven polypropylene fabrics that are commonly used as filtration materials in N95 respirators via ultraviolet (UV)-initiated grafting of biocidal agents. Here, C12-quaternized benzophenone is simultaneously polymerized and grafted onto melt-blown or spunbond polypropylene fabric using 254 nm UV light. This grafting method generated ultrathin polymer coatings which imparted a permanent cationic charge without grossly changing fiber morphology or air resistance across the filter. For melt-blown polypropylene, which comprises the active filtration layer of N95 respirator masks, filtration efficiency was negatively impacted from 72.5 to 51.3% for uncoated and coated single-ply samples, respectively. Similarly, directly applying the antiviral polymer to full N95 masks decreased the filtration efficiency from 90.4 to 79.8%. This effect was due to the exposure of melt-blown polypropylene to organic solvents used in the coating process. However, N95-level filtration efficiency could be achieved by wearing coated spunbond polypropylene over an N95 mask or by fabricating N95 masks with coated spunbond as the exterior layer. Coated materials demonstrated broad-spectrum antimicrobial activity against several lipid-enveloped viruses, as well as Staphylococcus aureus and Escherichia coli bacteria. For example, a 4.3-log reduction in infectious MHV-A59 virus and a 3.3-log reduction in infectious SuHV-1 virus after contact with coated filters were observed, although the level of viral deactivation varied significantly depending on the virus strain and protocol for assaying infectivity.
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Affiliation(s)
- Mirco Sorci
- Department
of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
- Center
for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
| | - Tanner D. Fink
- Department
of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
- Center
for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
| | - Vaishali Sharma
- Department
of Biological Sciences, Michigan Technological
University, 1400 Townsend Drive, Houghton, Michigan 49931, United
States
- Health
Research Institute, Michigan Technological
University, 1400 Townsend Drive, Houghton, Michigan 49931, United
States
| | - Sneha Singh
- Health
Research Institute, Michigan Technological
University, 1400 Townsend Drive, Houghton, Michigan 49931, United
States
- Department
of Chemical Engineering, Michigan Technological
University, 1400 Townsend Drive, Houghton, Michigan 49931, United
States
| | - Ruiwen Chen
- Department
of Materials Science and Engineering, Rensselaer
Polytechnic Institute, 110 8th Street, Troy, New
York 12180, United
States
| | - Brigitte L. Arduini
- Center
for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
| | - Katharine Dovidenko
- Center
for Materials, Devices, and Integrated Systems, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
| | - Caryn L. Heldt
- Health
Research Institute, Michigan Technological
University, 1400 Townsend Drive, Houghton, Michigan 49931, United
States
- Department
of Chemical Engineering, Michigan Technological
University, 1400 Townsend Drive, Houghton, Michigan 49931, United
States
| | - Edmund F. Palermo
- Department
of Materials Science and Engineering, Rensselaer
Polytechnic Institute, 110 8th Street, Troy, New
York 12180, United
States
| | - R. Helen Zha
- Department
of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
- Center
for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
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10
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Skudra A, Revalde G, Zajakina A, Mezule L, Spunde K, Juhna T, Rancane K. UV inactivation of Semliki Forest virus and bacteria by alternative light sources. Journal of Photochemistry and Photobiology 2022; 10:100120. [PMID: 35437519 PMCID: PMC8994679 DOI: 10.1016/j.jpap.2022.100120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The quick spreading of the SARS-CoV-2 virus, initiating the global pandemic with a significant impact on economics and health, highlighted an urgent need for effective and sustainable restriction mechanisms of pathogenic microorganisms. UV-C radiation, causing inactivation of many viruses and bacteria, is one of the tools for disinfection of different surfaces, liquids, and air; however, mainly mercury 254 nm line is commonly used for it. In this paper, we report our results of the experiments with newly elaborated special type polychromatic non-mercury UV light sources, having spectral lines in the spectral region from 190 nm to 280 nm. Inactivation tests were performed with both Escherichia coli (E.coli) bacteria and Semliki Forest virus (SFV) as a representative of human enveloped RNA viruses. In addition, the effect of prepared lamps on virus samples in liquid and dry form (dried virus-containing solution) was tested. Reduction of 4 log10 of E.coli was obtained after 10 min of irradiation with both thallium-antimony and arsenic high-frequency electrodeless lamps. High reduction results for the arsenic light source demonstrated sensitivity of E. coli to wavelengths below 230 nm, including spectral lines around 200 nm. For the Semliki Forest virus, the thallium-antimony light source showed virus inactivation efficiency with a high virus reduction rate in the range of 3.10 to > 4.99 log10 within 5 min of exposure. Thus, the new thallium-antimony light source showed the most promising disinfection effect in bacteria and viruses, and arsenic light sources for bacteria inactivation, opening doors for many applications in disinfection systems, including for pathogenic human RNA viruses.
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11
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Chirisa I, Mavhima B, Nyevera T, Chigudu A, Makochekanwa A, Matai J, Masunda T, Chandaengerwa EK, Machingura F, Moyo S, Chirisa H, Mhloyi M, Murwira A, Mhandara L, Katsande R, Muchena K, Manjeya E, Nyika T, Mundau L. The impact and implications of COVID-19: Reflections on the Zimbabwean society. ACTA ACUST UNITED AC 2021; 4:100183. [PMID: 34746754 PMCID: PMC8558728 DOI: 10.1016/j.ssaho.2021.100183] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/16/2021] [Accepted: 06/29/2021] [Indexed: 01/10/2023]
Abstract
The article is an attempt to provide a kaleidoscopic interpretation of how social science scholarship views the socio-cultural terrain of Zimbabwe during and after the global health crisis, and the societal and business haemorrhage induced by the coronavirus (COVID-19). Built through a multi-perspective and triangulation involving a modified Delphic approach that engages archival methods involving document and literature review, content analysis and expert interpretation; the article unveils the various effects of COVID-19 on Zimbabwe. It is concluded that COVID-19 by its nature is disruptive to everyday life, restrictive to human-social relations and is an instigator to tradition, spirituality and intellectuality in the country. The challenge of the virus brings to society a deliberate consciousness that global processes and events are converging (borders are porous) while local embeddedness is being entrenched through practices like lockdowns and confinement.
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Affiliation(s)
- Innocent Chirisa
- Department of Architecture and Real Estate, University of Zimbabwe, Zimbabwe.,Department of Urban and Regional Planning, University of the Free State, Zimbabwe
| | - Brilliant Mavhima
- Department of Architecture and Real Estate, University of Zimbabwe, Zimbabwe
| | - Tariro Nyevera
- Department of Architecture and Real Estate, University of Zimbabwe, Zimbabwe
| | - Andrew Chigudu
- Department of Architecture and Real Estate, University of Zimbabwe, Zimbabwe
| | | | - Joefrey Matai
- Department of Architecture and Real Estate, University of Zimbabwe, Zimbabwe
| | | | - Eve K Chandaengerwa
- Department of Community & Social Development, University of Zimbabwe, Zimbabwe
| | | | - Stanzia Moyo
- Demography Settlement and Development, University of Zimbabwe, Zimbabwe
| | - Halleluah Chirisa
- Population Services International & National AIDS Council Zimbabwe, Zimbabwe
| | - Marvellous Mhloyi
- Demography Settlement and Development, University of Zimbabwe, Zimbabwe
| | - Ashton Murwira
- Department of Governance and Public Management, University of Zimbabwe, Zimbabwe
| | - Lawrence Mhandara
- Department of Governance and Public Management, University of Zimbabwe, Zimbabwe
| | | | | | - Elton Manjeya
- Department of Architecture and Real Estate, University of Zimbabwe, Zimbabwe
| | - Teresa Nyika
- Department of Economics & Development, University of Zimbabwe, Zimbabwe
| | - Langton Mundau
- Department of Social Work, University of Zimbabwe, Zimbabwe
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12
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Viana Martins CP, Xavier CSF, Cobrado L. Disinfection methods against SARS-CoV-2: a systematic review. J Hosp Infect 2021; 119:84-117. [PMID: 34673114 PMCID: PMC8522489 DOI: 10.1016/j.jhin.2021.07.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [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: 04/14/2021] [Revised: 07/01/2021] [Accepted: 07/26/2021] [Indexed: 12/20/2022]
Abstract
Background Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of coronavirus disease 2019, has caused millions of deaths worldwide. The virus is transmitted by inhalation of infectious particles suspended in the air, direct deposition on mucous membranes and indirect contact via contaminated surfaces. Disinfection methods that can halt such transmission are important in this pandemic and in future viral infections. Aim To highlight the efficacy of several disinfection methods against SARS-CoV-2 based on up-to-date evidence found in the literature. Methods Two databases were searched to identify studies that assessed disinfection methods used against SARS-CoV-2. In total, 1229 studies were identified and 60 of these were included in this review. Quality assessment was evaluated by the Office of Health Assessment and Translation's risk-of-bias tool. Findings Twenty-eight studies investigated disinfection methods on environmental surfaces, 16 studies investigated disinfection methods on biological surfaces, four studies investigated disinfection methods for airborne coronavirus, and 16 studies investigated methods used to recondition personal protective equipment (PPE). Conclusions Several household and hospital disinfection agents and ultraviolet-C (UV-C) irradiation were effective for inactivation of SARS-CoV-2 on environmental surfaces. Formulations containing povidone-iodine can provide virucidal action on the skin and mucous membranes. In the case of hand hygiene, typical soap bars and alcohols can inactivate SARS-CoV-2. Air filtration systems incorporated with materials that possess catalytic properties, UV-C devices and heating systems can reduce airborne viral particles effectively. The decontamination of PPE can be conducted safely by heat and ozone treatment.
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Affiliation(s)
| | - C S F Xavier
- Faculty of Medicine, University of Porto, Porto, Portugal
| | - L Cobrado
- Division of Microbiology, Department of Pathology, Faculty of Medicine, University of Porto, Porto, Portugal; CINTESIS, Centre for Health Technology and Science Research, Porto, Portugal; Burn Unit and Department of Plastic and Reconstructive Surgery, University Hospital Centre of São João, Porto, Portugal
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13
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Doshi S, Banavar SP, Flaum E, Kulkarni S, Vaidya U, Kumar S, Chen T, Bhattacharya A, Prakash M. Applying heat and humidity using stove boiled water for decontamination of N95 respirators in low resource settings. PLoS One 2021; 16:e0255338. [PMID: 34591858 PMCID: PMC8483377 DOI: 10.1371/journal.pone.0255338] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 07/14/2021] [Indexed: 11/27/2022] Open
Abstract
Global shortages of N95 respirators have led to an urgent need of N95 decontamination and reuse methods that are scientifically validated and available world-wide. Although several large scale decontamination methods have been proposed (hydrogen peroxide vapor, UV-C); many of them are not applicable in remote and low-resource settings. Heat with humidity has been demonstrated as a promising decontamination approach, but care must be taken when implementing this method at a grassroots level. Here we present a simple, scalable method to provide controlled humidity and temperature for individual N95 respirators which is easily applicable in low-resource settings. N95 respirators were subjected to moist heat (>50% relative humidity, 65-80°C temperature) for over 30 minutes by placing them in a sealed container immersed in water that had been brought to a rolling boil and removed from heat, and then allowing the containers to sit for over 45 minutes. Filtration efficiency of 0.3-4.99 μm incense particles remained above 97% after 5 treatment cycles across all particle size sub-ranges. This method was then repeated at a higher ambient temperature and humidity in Mumbai, using standard utensils commonly found in South Asia. Similar temperature and humidity profiles were achieved with no degradation in filtration efficiencies after 6 cycles. Higher temperatures (>70°C) and longer treatment times (>40 minutes) were obtained by insulating the outer vessel. We also showed that the same method can be applied for the decontamination of surgical masks. This simple yet reliable method can be performed even without electricity access using any heat source to boil water, from open-flame stoves to solar heating, and provides a low-cost route for N95 decontamination globally applicable in resource-constrained settings.
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Affiliation(s)
- Siddharth Doshi
- Department of Materials Science and Engineering, Stanford University, Stanford, California, United States of America
| | - Samhita P. Banavar
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Eliott Flaum
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
- Graduate Program in Biophysics, Stanford University, Stanford, California, United States of America
| | | | - Ulhas Vaidya
- Tata Institute of Fundamental Research, Mumbai, India
| | - Shailabh Kumar
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Tyler Chen
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | | | - Manu Prakash
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
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14
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Gamble A, Fischer RJ, Morris DH, Yinda CK, Munster VJ, Lloyd-Smith JO. Heat-Treated Virus Inactivation Rate Depends Strongly on Treatment Procedure: Illustration with SARS-CoV-2. Appl Environ Microbiol 2021; 87:e0031421. [PMID: 34288702 PMCID: PMC8432576 DOI: 10.1128/aem.00314-21] [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: 03/23/2021] [Accepted: 07/12/2021] [Indexed: 12/05/2022] Open
Abstract
Decontamination helps limit environmental transmission of infectious agents. It is required for the safe reuse of contaminated medical, laboratory, and personal protective equipment, and for the safe handling of biological samples. Heat treatment is a common decontamination method, notably used for viruses. We show that for liquid specimens (here, solution of SARS-CoV-2 in cell culture medium), the virus inactivation rate under heat treatment at 70°C can vary by almost two orders of magnitude depending on the treatment procedure, from a half-life of 0.86 min (95% credible interval [CI] 0.09, 1.77) in closed vials in a heat block to 37.04 min (95% CI 12.64, 869.82) in uncovered plates in a dry oven. These findings suggest a critical role of evaporation in virus inactivation via dry heat. Placing samples in open or uncovered containers may dramatically reduce the speed and efficacy of heat treatment for virus inactivation. Given these findings, we reviewed the literature on temperature-dependent coronavirus stability and found that specimen container types, along with whether they are closed, covered, or uncovered, are rarely reported in the scientific literature. Heat-treatment procedures must be fully specified when reporting experimental studies to facilitate result interpretation and reproducibility, and must be carefully considered when developing decontamination guidelines. IMPORTANCE Heat is a powerful weapon against most infectious agents. It is widely used for decontamination of medical, laboratory, and personal protective equipment, and for biological samples. There are many methods of heat treatment, and methodological details can affect speed and efficacy of decontamination. We applied four different heat-treatment procedures to liquid specimens containing SARS-CoV-2. Our results show that the container used to store specimens during decontamination can substantially affect inactivation rate; for a given initial level of contamination, decontamination time can vary from a few minutes in closed vials to several hours in uncovered plates. Reviewing the literature, we found that container choices and heat treatment methods are only rarely reported explicitly in methods sections. Our study shows that careful consideration of heat-treatment procedure-in particular the choice of specimen container and whether it is covered-can make results more consistent across studies, improve decontamination practice, and provide insight into the mechanisms of virus inactivation.
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Affiliation(s)
- Amandine Gamble
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, California, USA
| | - Robert J. Fischer
- Laboratory of Virology, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, USA
| | - Dylan H. Morris
- Department of Ecology & Evolutionary Biology, Princeton University, New Jersey, USA
| | - Claude Kwe Yinda
- Laboratory of Virology, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, USA
| | - Vincent J. Munster
- Laboratory of Virology, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, USA
| | - James O. Lloyd-Smith
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, California, USA
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15
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Singh G, Jorgenson J, Pringle T, Nelson T, Ramamoorthy S. Monitoring SARS-CoV-2 decontamination by dry heat and ultraviolet treatment with a swine coronavirus as a surrogate. Infect Prev Pract 2021; 3:100103. [PMID: 34316570 PMCID: PMC7694467 DOI: 10.1016/j.infpip.2020.100103] [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] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 11/18/2020] [Indexed: 01/17/2023] Open
Abstract
The critical need for reliable methods to validate decontamination protocols for personal protective equipment (PPE) for re-use during the SARS-CoV-2 pandemic is limited by the need for specialized containment facilities to handle the virus. Hence, we have herein validated the use of a swine coronavirus as a surrogate, and tested the effectiveness of dry heat and ultraviolet (UV) rays for PPE decontamination. Exposure of experimentally contaminated N95 masks and hospital gowns to 60°C for 20 min, and UVC at 1800 mJ/cm2 resulted in a 4-log reduction and inactivation of the surrogate virus. This study provides a novel alternative to validate PPE reprocessing methods.
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Affiliation(s)
- G Singh
- Department of Microbiological Sciences, North Dakota State University, Fargo, ND, USA
| | - J Jorgenson
- Blue Water Resolute (BWR) Innovations, Fargo, ND, USA
| | | | - T Nelson
- Blue Water Resolute (BWR) Innovations, Fargo, ND, USA
| | - S Ramamoorthy
- Department of Microbiological Sciences, North Dakota State University, Fargo, ND, USA
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16
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Gamble A, Fischer RJ, Morris DH, Yinda KC, Munster VJ, Lloyd-Smith JO. Heat-treated virus inactivation rate depends strongly on treatment procedure: illustration with SARS-CoV-2. bioRxiv 2021:2020.08.10.242206. [PMID: 32793913 PMCID: PMC7425175 DOI: 10.1101/2020.08.10.242206] [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] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Decontamination helps limit environmental transmission of infectious agents. It is required for the safe re-use of contaminated medical, laboratory and personal protective equipment, and for the safe handling of biological samples. Heat treatment is a common decontamination method, notably used for viruses. We show that for liquid specimens (here, solution of SARS-CoV-2 in cell culture medium), virus inactivation rate under heat treatment at 70°C can vary by almost two orders of magnitude depending on the treatment procedure, from a half-life of 0.86 min (95% credible interval: [0.09, 1.77]) in closed vials in a heat block to 37.00 min ([12.65, 869.82]) in uncovered plates in a dry oven. These findings suggest a critical role of evaporation in virus inactivation via dry heat. Placing samples in open or uncovered containers may dramatically reduce the speed and efficacy of heat treatment for virus inactivation. Given these findings, we reviewed the literature temperature-dependent coronavirus stability and found that specimen containers, and whether they are closed, covered, or uncovered, are rarely reported in the scientific literature. Heat-treatment procedures must be fully specified when reporting experimental studies to facilitate result interpretation and reproducibility, and must be carefully considered when developing decontamination guidelines.
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Affiliation(s)
- Amandine Gamble
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, CA, USA
| | - Robert J. Fischer
- Laboratory of Virology, National Institute of Allergy and Infectious Diseases, Hamilton, MT, USA
| | - Dylan H. Morris
- Department of Ecology & Evolutionary Biology, Princeton University, NJ, USA
| | - Kwe Claude Yinda
- Laboratory of Virology, National Institute of Allergy and Infectious Diseases, Hamilton, MT, USA
| | - Vincent J. Munster
- Laboratory of Virology, National Institute of Allergy and Infectious Diseases, Hamilton, MT, USA
| | - James O. Lloyd-Smith
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, CA, USA
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17
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Anderegg L, Doyle J, Gardel ML, Gupta A, Hallas C, Lensky Y, Love NG, Lucas BA, Mazenc E, Meisenhelder C, Pillarisetti A, Ranard D, Squires AH, Vechakul J, Vilas NB, Williams S, Wilson D, Chen TN. Heat and Humidity for Bioburden Reduction of N95 Filtering Facepiece Respirators. Applied Biosafety 2021; 26:80-89. [DOI: 10.1089/apb.20.0053] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Loïc Anderegg
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Harvard/MIT Center for Ultracold Atoms, Cambridge, Massachusetts, USA
| | - John Doyle
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Harvard/MIT Center for Ultracold Atoms, Cambridge, Massachusetts, USA
| | - Margaret L. Gardel
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois, USA
- Department of Physics, The University of Chicago, Chicago, Illinois, USA
| | - Amit Gupta
- Consolidated Sterilizer Systems, Billerica, Massachusetts, USA
| | - Christian Hallas
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Harvard/MIT Center for Ultracold Atoms, Cambridge, Massachusetts, USA
| | - Yuri Lensky
- Department of Physics, Stanford University, Stanford, California, USA
| | - Nancy G. Love
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Edward Mazenc
- Department of Physics, Stanford University, Stanford, California, USA
| | - Cole Meisenhelder
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Harvard/MIT Center for Ultracold Atoms, Cambridge, Massachusetts, USA
| | - Ajay Pillarisetti
- PPE Sanitizer Group, Vallejo, California, USA
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Daniel Ranard
- Department of Physics, Stanford University, Stanford, California, USA
| | - Allison H. Squires
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois, USA
| | | | - Nathaniel B. Vilas
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Harvard/MIT Center for Ultracold Atoms, Cambridge, Massachusetts, USA
| | | | | | - Tyler N. Chen
- Department of Bioengineering, Stanford University, Stanford, California, USA
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18
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Perkins DJ, Nofchissey RA, Ye C, Donart N, Kell A, Foo-Hurwitz I, Muller T, Bradfute SB. COVID-19 global pandemic planning: Dry heat incubation and ambient temperature fail to consistently inactivate SARS-CoV-2 on N95 respirators. Exp Biol Med (Maywood) 2021; 246:952-959. [PMID: 33342283 PMCID: PMC7750684 DOI: 10.1177/1535370220977819] [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: 10/20/2020] [Accepted: 11/10/2020] [Indexed: 11/25/2022] Open
Abstract
The ongoing pandemic of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has placed a substantial strain on the supply of personal protective equipment, particularly the availability of N95 respirators for frontline healthcare personnel. These shortages have led to the creation of protocols to disinfect and reuse potentially contaminated personal protective equipment. A simple and inexpensive decontamination procedure that does not rely on the use of consumable supplies is dry heat incubation. Although reprocessing with this method has been shown to maintain the integrity of N95 respirators after multiple decontamination procedures, information on the ability of dry heat incubation to inactivate SARS-CoV-2 is largely unreported. Here, we show that dry heat incubation does not consistently inactivate SARS-CoV-2-contaminated N95 respirators, and that variation in experimental conditions can dramatically affect viability of the virus. Furthermore, we show that SARS-CoV-2 can survive on N95 respirators that remain at room temperature for at least five days. Collectively, our findings demonstrate that dry heat incubation procedures and ambient temperature for five days are not viable methods for inactivating SARS-CoV-2 on N95 respirators for potential reuse. We recommend that decontamination procedures being considered for the reuse of N95 respirators be validated at each individual site and that validation of the process must be thoroughly conducted using a defined protocol.
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Affiliation(s)
- Douglas J Perkins
- Center for Global Health, Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Robert A Nofchissey
- Center for Global Health, Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Chunyan Ye
- Center for Global Health, Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Nathan Donart
- Office of Research, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Alison Kell
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Ivy Foo-Hurwitz
- Center for Global Health, Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Timothy Muller
- Office of Research, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Steven B Bradfute
- Center for Global Health, Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
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19
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Wigginton KR, Arts PJ, Clack HL, Fitzsimmons WJ, Gamba M, Harrison KR, LeBar W, Lauring AS, Li L, Roberts WW, Rockey NC, Torreblanca J, Young C, Anderegg LG, Cohn AM, Doyle JM, Meisenhelder CM, Raskin L, Love NG, Kaye KS. Validation of N95 Filtering Facepiece Respirator Decontamination Methods Available at a Large University Hospital. Open Forum Infect Dis 2021; 8:ofaa610. [PMID: 33575418 DOI: 10.1101/2020.04.28.20084038] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/09/2020] [Indexed: 05/26/2023] Open
Abstract
BACKGROUND Due to unprecedented shortages in N95 filtering facepiece respirators, healthcare systems have explored N95 reprocessing. No single, full-scale reprocessing publication has reported an evaluation including multiple viruses, bacteria, and fungi along with respirator filtration and fit. METHODS We explored reprocessing methods using new 3M 1860 N95 respirators, including moist (50%-75% relative humidity [RH]) heat (80-82°C for 30 minutes), ethylene oxide (EtO), pulsed xenon UV-C (UV-PX), hydrogen peroxide gas plasma (HPGP), and hydrogen peroxide vapor (HPV). Respirator samples were analyzed using 4 viruses (MS2, phi6, influenza A virus [IAV], murine hepatitis virus [MHV)]), 3 bacteria (Escherichia coli, Staphylococcus aureus, Geobacillus stearothermophilus spores, and vegetative bacteria), and Aspergillus niger. Different application media were tested. Decontaminated respirators were evaluated for filtration integrity and fit. RESULTS Heat with moderate RH most effectively inactivated virus, resulting in reductions of >6.6-log10 MS2, >6.7-log10 Phi6, >2.7-log10 MHV, and >3.9-log10 IAV and prokaryotes, except for G stearothermohphilus. Hydrogen peroxide vapor was moderately effective at inactivating tested viruses, resulting in 1.5- to >4-log10 observable inactivation. Staphylococcus aureus inactivation by HPV was limited. Filtration efficiency and proper fit were maintained after 5 cycles of heat with moderate RH and HPV. Although it was effective at decontamination, HPGP resulted in decreased filtration efficiency, and EtO treatment raised toxicity concerns. Observed virus inactivation varied depending upon the application media used. CONCLUSIONS Both moist heat and HPV are scalable N95 reprocessing options because they achieve high levels of biological indicator inactivation while maintaining respirator fit and integrity.
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Affiliation(s)
- Krista R Wigginton
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Peter J Arts
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Herek L Clack
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - William J Fitzsimmons
- Division of Infectious Diseases, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Mirko Gamba
- Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Katherine R Harrison
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - William LeBar
- Department of Pathology, Clinical Microbiology, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Adam S Lauring
- Division of Infectious Diseases, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Lucinda Li
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - William W Roberts
- Department of Urology, University of Michigan Health System, Ann Arbor, Michigan, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Nicole C Rockey
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Jania Torreblanca
- Department of Pathology, Clinical Microbiology, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Carol Young
- Department of Pathology, Clinical Microbiology, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Loïc G Anderegg
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts, USA
| | - Amy M Cohn
- Department of Industrial & Operations Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - John M Doyle
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts, USA
| | | | - Lutgarde Raskin
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Nancy G Love
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Keith S Kaye
- Division of Infectious Diseases, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, Michigan, USA
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20
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Wigginton KR, Arts PJ, Clack HL, Fitzsimmons WJ, Gamba M, Harrison KR, LeBar W, Lauring AS, Li L, Roberts WW, Rockey NC, Torreblanca J, Young C, Anderegg LG, Cohn AM, Doyle JM, Meisenhelder CM, Raskin L, Love NG, Kaye KS. Validation of N95 Filtering Facepiece Respirator Decontamination Methods Available at a Large University Hospital. Open Forum Infect Dis 2021; 8:ofaa610. [PMID: 33575418 PMCID: PMC7863868 DOI: 10.1093/ofid/ofaa610] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/09/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Due to unprecedented shortages in N95 filtering facepiece respirators, healthcare systems have explored N95 reprocessing. No single, full-scale reprocessing publication has reported an evaluation including multiple viruses, bacteria, and fungi along with respirator filtration and fit. METHODS We explored reprocessing methods using new 3M 1860 N95 respirators, including moist (50%-75% relative humidity [RH]) heat (80-82°C for 30 minutes), ethylene oxide (EtO), pulsed xenon UV-C (UV-PX), hydrogen peroxide gas plasma (HPGP), and hydrogen peroxide vapor (HPV). Respirator samples were analyzed using 4 viruses (MS2, phi6, influenza A virus [IAV], murine hepatitis virus [MHV)]), 3 bacteria (Escherichia coli, Staphylococcus aureus, Geobacillus stearothermophilus spores, and vegetative bacteria), and Aspergillus niger. Different application media were tested. Decontaminated respirators were evaluated for filtration integrity and fit. RESULTS Heat with moderate RH most effectively inactivated virus, resulting in reductions of >6.6-log10 MS2, >6.7-log10 Phi6, >2.7-log10 MHV, and >3.9-log10 IAV and prokaryotes, except for G stearothermohphilus. Hydrogen peroxide vapor was moderately effective at inactivating tested viruses, resulting in 1.5- to >4-log10 observable inactivation. Staphylococcus aureus inactivation by HPV was limited. Filtration efficiency and proper fit were maintained after 5 cycles of heat with moderate RH and HPV. Although it was effective at decontamination, HPGP resulted in decreased filtration efficiency, and EtO treatment raised toxicity concerns. Observed virus inactivation varied depending upon the application media used. CONCLUSIONS Both moist heat and HPV are scalable N95 reprocessing options because they achieve high levels of biological indicator inactivation while maintaining respirator fit and integrity.
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Affiliation(s)
- Krista R Wigginton
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Peter J Arts
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Herek L Clack
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - William J Fitzsimmons
- Division of Infectious Diseases, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Mirko Gamba
- Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Katherine R Harrison
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - William LeBar
- Department of Pathology, Clinical Microbiology, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Adam S Lauring
- Division of Infectious Diseases, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Lucinda Li
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - William W Roberts
- Department of Urology, University of Michigan Health System, Ann Arbor, Michigan, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Nicole C Rockey
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Jania Torreblanca
- Department of Pathology, Clinical Microbiology, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Carol Young
- Department of Pathology, Clinical Microbiology, University of Michigan Health System, Ann Arbor, Michigan, USA
| | - Loïc G Anderegg
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts, USA
| | - Amy M Cohn
- Department of Industrial & Operations Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - John M Doyle
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts, USA
| | | | - Lutgarde Raskin
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Nancy G Love
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Keith S Kaye
- Division of Infectious Diseases, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, Michigan, USA
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