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Sun W, Wang M, Shi Z, Wang P, Wang J, Du B, Wang S, Sun Z, Liu Z, Wei L, Yang D, He X, Wang J. VP2 mediates the release of the feline calicivirus RNA genome by puncturing the endosome membrane of infected cells. J Virol 2024; 98:e0035024. [PMID: 38591900 PMCID: PMC11092339 DOI: 10.1128/jvi.00350-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Accepted: 03/19/2024] [Indexed: 04/10/2024] Open
Abstract
Feline calicivirus (FCV) is one of the few members of the Caliciviridae family that grows well in cell lines and, therefore, serves as a surrogate to study the biology of other viruses in the family. Conley et al. (14) demonstrated that upon the receptor engagement to the capsid, FCV VP2 forms a portal-like assembly, which might provide a channel for RNA release. However, the process of calicivirus RNA release is not yet fully understood. Our findings suggest that the separation of the FCV capsid from its genome RNA (gRNA) occurs rapidly in the early endosomes of infected cells. Using a liposome model decorated with the FCV cell receptor fJAM-A, we demonstrate that FCV releases its gRNA into the liposomes by penetrating membranes under low pH conditions. Furthermore, we found that VP2, which is rich in hydrophobic residues at its N-terminus, functions as the pore-forming protein. When we substituted the VP2 N-terminal hydrophobic residues, the gRNA release efficacy of the FCV mutants decreased. In conclusion, our results suggest that in the acidic environment of early endosomes, FCV VP2 functions as the pore-forming protein to mediate gRNA release into the cytoplasm of infected cells. This provides insight into the mechanism of calicivirus genome release.IMPORTANCEResearch on the biology and pathogenicity of certain caliciviruses, such as Norovirus and Sapovirus, is hindered by the lack of easy-to-use cell culture system. Feline calicivirus (FCV), which grows effectively in cell lines, is used as a substitute. At present, there is limited understanding of the genome release mechanism in caliciviruses. Our findings suggest that FCV uses VP2 to pierce the endosome membrane for genome release and provide new insights into the calicivirus gRNA release mechanism.
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Affiliation(s)
- Weiyao Sun
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Ming Wang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Zhibin Shi
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Pengfei Wang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Jinhui Wang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Bingchen Du
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Shida Wang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Zhenzhao Sun
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Zaisi Liu
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Lili Wei
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Decheng Yang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Xijun He
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Jingfei Wang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
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Hiep NT, Nguyen MK, Nhut HT, Hung NTQ, Manh NC, Lin C, Chang SW, Um MJ, Nguyen DD. A review on sterilization methods of environmental decontamination to prevent the coronavirus SARS-CoV-2 (COVID-19 virus): A new challenge towards eco-friendly solutions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166021. [PMID: 37543323 DOI: 10.1016/j.scitotenv.2023.166021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 06/13/2023] [Accepted: 08/01/2023] [Indexed: 08/07/2023]
Abstract
In recent years, the COVID-19 pandemic is currently wreaking havoc on the planet. SARS-CoV-2, the Severe Acute Respiratory Syndrome Coronavirus, is the current term for this outbreak. Reports about this novel coronavirus have been presented since the pandemic's breakout, and they have demonstrated that it transmits rapidly from person to person, primarily by droplets in the air. Findings have illustrated that SARS-CoV-2 can survive on surfaces from hours to days. Therefore, it is essential to find practical solutions to reduce the virus's impact on human health and the environment. This work evaluated common sterilization methods that can decontaminate the environment and items. The goal is that healthcare facilities, disease prevention organizations, and local communities can overcome the new challenge of finding eco-friendly solutions. Further, a foundation of information encompassing various sterilization procedures and highlighting their limits to choose the most appropriate method to stop disease-causing viruses in the new context has been presented. The findings of this crucial investigation contribute to gaining insight into the comprehensive sterilization approaches against the coronavirus for human health protection and sustainable environmental development.
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Affiliation(s)
- Nguyen Trung Hiep
- Research Institute for Sustainable Development, Ho Chi Minh University of Natural Resources and Environment, 236B Le Van Sy, Ward 1, Tan Binh District, Ho Chi Minh City 700000, Viet Nam
| | - Minh-Ky Nguyen
- Faculty of Environment and Natural Resources, Nong Lam University, Linh Trung Ward, Thu Duc City, Ho Chi Minh City 700000, Viet Nam; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan
| | - Huynh Tan Nhut
- Faculty of Environment and Natural Resources, Nong Lam University, Linh Trung Ward, Thu Duc City, Ho Chi Minh City 700000, Viet Nam
| | - Nguyen Tri Quang Hung
- Faculty of Environment and Natural Resources, Nong Lam University, Linh Trung Ward, Thu Duc City, Ho Chi Minh City 700000, Viet Nam.
| | - Nguyen Cong Manh
- Department of Aquatic and Atmospheric Environment Research, Research Institute of Biotechnology and Environment, Nong Lam University, Ho Chi Minh City 700000, Viet Nam
| | - Chitsan Lin
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan
| | - S Woong Chang
- Department of Civil & Energy System Engineering, Kyonggi University, Suwon 16227, South Korea
| | - Myoung Jin Um
- Department of Civil & Energy System Engineering, Kyonggi University, Suwon 16227, South Korea
| | - D Duc Nguyen
- Department of Civil & Energy System Engineering, Kyonggi University, Suwon 16227, South Korea; Faculty of Environmental and Food Engineering, Nguyen Tat Thanh University, 300A Nguyen Tat Thanh, District 4, Ho Chi Minh City 755414, Viet Nam.
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3
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Frippiat T, Dams L, Wielick C, Delguste C, Ludwig-Begall LF, Art T, Thiry E. In vitro virucidal activity of nebulized citrate-complexed silver nanoparticles against equine herpesvirus-1 and murine norovirus. Virology 2023; 585:232-239. [PMID: 37406580 DOI: 10.1016/j.virol.2023.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 05/25/2023] [Accepted: 06/05/2023] [Indexed: 07/07/2023]
Abstract
Viruses can be involved in respiratory disorders in horses, with limited therapeutic options. Citrate-complexed silver nanoparticles (C-AgNP) have shown bactericidal properties after in vitro nebulization. The aim of the present study was to assess the virucidal activity of C-AgNP after in vitro instillation or nebulization on equine herpesvirus-1 (EHV-1) and murine norovirus (MNV), the latter used as surrogate for small non-enveloped viruses. Both viruses were instilled or nebulized with C-AgNP of increasing concentrations, and titres were determined via TCID50 method. We demonstrated efficient inactivation of enveloped EHV-1 following instillation and nebulization of C-AgNP (infectivity losses of ≥ three orders of magnitude). While tenacious MNV was inactivated via 2000 ppm C-AgNP instillation, nebulized C-AgNP did not lead to reduction in MNV titres. Nebulization of C-AgNP may represent a novel virucidal therapeutic approach in horses. Further investigations are needed to assess its safety and effective concentrations for in vivo use.
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Affiliation(s)
- Thibault Frippiat
- Equine Sports Medicine Centre, Faculty of Veterinary Medicine, University of Liege, Belgium; Sportpaardenarts - Equine Sports Medicine, Laren, the Netherlands.
| | - Lorène Dams
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Constance Wielick
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Catherine Delguste
- General Services, FARAH Research Centre, Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Louisa F Ludwig-Begall
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Tatiana Art
- Equine Sports Medicine Centre, Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Etienne Thiry
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, University of Liege, Belgium
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van der Starre CM, Cremers-Pijpers SAJ, van Rossum C, Bowles EC, Tostmann A. The in situ efficacy of whole room disinfection devices: a literature review with practical recommendations for implementation. Antimicrob Resist Infect Control 2022; 11:149. [PMID: 36471395 PMCID: PMC9724435 DOI: 10.1186/s13756-022-01183-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 11/10/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Terminal cleaning and disinfection of hospital patient rooms must be performed after discharge of a patient with a multidrug resistant micro-organism to eliminate pathogens from the environment. Terminal disinfection is often performed manually, which is prone to human errors and therefore poses an increased infection risk for the next patients. Automated whole room disinfection (WRD) replaces or adds on to the manual process of disinfection and can contribute to the quality of terminal disinfection. While the in vitro efficacy of WRD devices has been extensively investigated and reviewed, little is known about the in situ efficacy in a real-life hospital setting. In this review, we summarize available literature on the in situ efficacy of WRD devices in a hospital setting and compare findings to the in vitro efficacy of WRD devices. Moreover, we offer practical recommendations for the implementation of WRD devices. METHODS The in situ efficacy was summarized for four commonly used types of WRD devices: aerosolized hydrogen peroxide, H2O2 vapour, ultraviolet C and pulsed xenon ultraviolet. The in situ efficacy was based on environmental and clinical outcome measures. A systematic literature search was performed in PubMed in September 2021 to identify available literature. For each disinfection system, we summarized the available devices, practical information, in vitro efficacy and in situ efficacy. RESULTS In total, 54 articles were included. Articles reporting environmental outcomes of WRD devices had large variation in methodology, reported outcome measures, preparation of the patient room prior to environmental sampling, the location of sampling within the room and the moment of sampling. For the clinical outcome measures, all included articles reported the infection rate. Overall, these studies consistently showed that automated disinfection using any of the four types of WRD is effective in reducing environmental and clinical outcomes. CONCLUSION Despite the large variation in the included studies, the four automated WRD systems are effective in reducing the amount of pathogens present in a hospital environment, which was also in line with conclusions from in vitro studies. Therefore, the assessment of what WRD device would be most suitable in a specific healthcare setting mostly depends on practical considerations.
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Affiliation(s)
- Caroline M. van der Starre
- grid.10417.330000 0004 0444 9382Unit of Hygiene and Infection Prevention, Department of Medical Microbiology, Radboud Center for Infectious Diseases (RCI), Radboudumc, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands
| | - Suzan A. J. Cremers-Pijpers
- grid.10417.330000 0004 0444 9382Unit of Hygiene and Infection Prevention, Department of Medical Microbiology, Radboud Center for Infectious Diseases (RCI), Radboudumc, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands
| | - Carsten van Rossum
- grid.10417.330000 0004 0444 9382Unit of Hygiene and Infection Prevention, Department of Medical Microbiology, Radboud Center for Infectious Diseases (RCI), Radboudumc, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands
| | - Edmée C. Bowles
- grid.10417.330000 0004 0444 9382Unit of Hygiene and Infection Prevention, Department of Medical Microbiology, Radboud Center for Infectious Diseases (RCI), Radboudumc, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands
| | - Alma Tostmann
- grid.10417.330000 0004 0444 9382Unit of Hygiene and Infection Prevention, Department of Medical Microbiology, Radboud Center for Infectious Diseases (RCI), Radboudumc, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands
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Ezzatpanah H, Gómez‐López VM, Koutchma T, Lavafpour F, Moerman F, Mohammadi M, Raheem D. New food safety challenges of viral contamination from a global perspective: Conventional, emerging, and novel methods of viral control. Compr Rev Food Sci Food Saf 2022; 21:904-941. [DOI: 10.1111/1541-4337.12909] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 12/13/2021] [Accepted: 12/16/2021] [Indexed: 12/11/2022]
Affiliation(s)
- Hamid Ezzatpanah
- Department of Food Science and Technology, Science and Research Branch Islamic Azad University Tehran Iran
| | | | - Tatiana Koutchma
- Guelph Research and Development Center Agriculture and Agri‐Food Canada Guelph Ontario Canada
| | | | - Frank Moerman
- Department of Chemistry Catholic University of Leuven ‐ KU Leuven Leuven Belgium
| | | | - Dele Raheem
- Arctic Centre (NIEM) University of Lapland Rovaniemi Finland
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Moon Y, Han S, Son JW, Park SH, Ha SD. Impact of ultraviolet-C and peroxyacetic acid against murine norovirus on stainless steel and lettuce. Food Control 2021. [DOI: 10.1016/j.foodcont.2021.108378] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Song WJ, Kang DH. Inactivation of Escherichia coli O157:H7 and Salmonella Typhimurium in black and red pepper by vacuumed hydrogen peroxide vapour. J Appl Microbiol 2021; 132:290-297. [PMID: 34310828 DOI: 10.1111/jam.15230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 06/14/2021] [Accepted: 07/14/2021] [Indexed: 11/29/2022]
Abstract
AIMS In this study, the efficacy of using vacuumed hydrogen peroxide vapour (VHPV) to inactivate foodborne pathogens in whole dried black pepper (Piper nigrum) and powdered dried red pepper (Capsicum annuum) was evaluated. METHODS AND RESULTS Black and red pepper inoculated with Escherichia coli O157:H7 and Salmonella Typhimurium were subjected to 3.81, 7.93, 12.33, 17.04 and 21.67 mg l-1 VHPV for 1 min, and the change in pepper colour was evaluated after treatment. Pathogen quantities decreased with increasing hydrogen peroxide concentration. For black pepper, the 21.67 mg l-1 VHPV treatment decreased E. coli O157:H7 and S. Typhimurium quantities by >6.12 and 4.52 log CFU per gram, respectively, without causing colour change. In addition, the 21.67 mg l-1 VHPV treatment caused 4.35 and 2.36 log CFU per gram reductions in these two pathogen quantities in red pepper, respectively. During the VHPV treatment, colour values of peppers did not significantly change. CONCLUSIONS VHPV effectively reduced the levels of foodborne pathogens in black and red pepper while inducing minimal colour changes. SIGNIFICANCE AND IMPACT OF THE STUDY Hydrogen peroxide vapour (HPV) is typically used as a sterilization method for medical devices, and many studies have confirmed the effectiveness of HPV or the gaseous phase of hydrogen peroxide on the inactivation of micro-organisms. However, using HPV for food pasteurization has rarely been studied. In the present study, we confirmed that VHPV effectively reduced the levels of pathogens in black and red pepper without colour changes.
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Affiliation(s)
- Won-Jae Song
- Department of Food Science and Biotechnology, Kyonggi University, Suwon, Republic of Korea
| | - Dong-Hyun Kang
- Department of Agricultural Biotechnology, Center for Food and Bioconvergence, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea.,Institutes of Green Bio Science & Technology, Seoul National University, Gangwon-do, Republic of Korea
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Cervantes Trejo A, Castañeda ID, Rodríguez AC, Andrade Carmona VR, Mercado MDPC, Vale LS, Cruz M, Barrero Castillero S, Consuelo LC, Di Silvio M. Hydrogen Peroxide as an Adjuvant Therapy for COVID-19: A Case Series of Patients and Caregivers in the Mexico City Metropolitan Area. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2021; 2021:5592042. [PMID: 34335827 PMCID: PMC8289588 DOI: 10.1155/2021/5592042] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/12/2021] [Accepted: 05/18/2021] [Indexed: 12/17/2022]
Abstract
Knowledge of the antiseptic effects of hydrogen peroxide (H2O2) dates back to the late 19th century, and its mechanisms of action has been amply described. Globally, many physicians have reported using H2O2 successfully, in different modalities, against COVID-19. Given its anti-infective and oxygenating properties, hydrogen peroxide may offer prophylactic and therapeutic applications for responding to the COVID-19 pandemic. We report a consecutive case series of twenty-three COVID-19 patients (of 36 initially enrolled) who had been diagnosed by their primary care physician (mean age: 39, range: 8 months-70 years; 74% male) and twenty-eight caregivers in the Mexico City Metropolitan Area who received a complementary and alternative medicine (CAM) telemedicine treatment with H2O2 taken by mouth (PO, at a concentration of 0.06%), oral rinse (mouthwash, 1.5%), and/or nebulization (0.2%). We describe the treatment program and report the response of the COVID-19 patients and their caregivers. The patients mainly recovered well, reporting feeling "completely better" at 9.5 days on average. Two (9%) were hospitalized prior to joining the study, and one did not fully recover. Patients frequently reported nausea and sometimes dizziness or vomiting related to the oral treatment. None of the twenty-eight caregivers in close contact with the patients reported contracting COVID-19. Given its low cost and medical potential and considering its relative safety if used properly, we suggest that randomized controlled trials should be conducted. These should include both SARS-CoV-2-positive and SARS-CoV-2-negative participants, with single or combined modes of administration of H2O2, to study the benefits of this simple molecule and offer safe guidance regarding its use by health professionals.
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Affiliation(s)
- Arturo Cervantes Trejo
- Carlos Peralta Professor and Chair of Public Health, Anahuac Institute of Public Health, Faculty of Health Sciences, Anahuac University Mexico, Naucalpan de Juárez 52786, Mexico
| | - Isaac D. Castañeda
- Carlos Peralta Chair of Public Health, Anahuac Institute of Public Health, Faculty of Health Sciences, Anahuac University Mexico, Naucalpan de Juárez 52786, Mexico
| | - Alejandra Cortés Rodríguez
- Bursary Scholar of Medicine, Anahuac Institute of Public Health, Faculty of Health Sciences, Anahuac University Mexico, Naucalpan de Juárez 52786, Mexico
| | - Victor R. Andrade Carmona
- Bursary Scholar of Medicine, Anahuac Institute of Public Health, Faculty of Health Sciences, Anahuac University Mexico, Naucalpan de Juárez 52786, Mexico
| | - M. del Pilar Calva Mercado
- Faculty of Bioethics and Faculty of Health Sciences, Anahuac University Mexico, Naucalpan de Juárez 52786, Mexico
| | - Liliana Salgado Vale
- Bursary Scholar of Medicine, Anahuac Institute of Public Health, Faculty of Health Sciences, Anahuac University Mexico, Naucalpan de Juárez 52786, Mexico
| | - Montserrat Cruz
- School of Medicine, Universidad de Monterrey, San Pedro Garza García, Mexico
| | | | - Lucero Chavez Consuelo
- Bursary Scholar of Medicine, Anahuac Institute of Public Health, Faculty of Health Sciences, Anahuac University Mexico, Naucalpan de Juárez 52786, Mexico
| | - Mauricio Di Silvio
- Fellow of the American College of Surgeons (FACS), Medical Director of Hospital Mac Periferico Sur, Mexico City, Coyoacan 04700, Mexico
- Faculty of Health Sciences, Anahuac University Mexico, Naucalpan de Juárez 52786, Mexico
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Thaper R, Fagen B, Oh J. Decontamination of respirators amid shortages due to SARS-CoV-2. Photochem Photobiol Sci 2021; 20:955-965. [PMID: 34118013 PMCID: PMC8196272 DOI: 10.1007/s43630-021-00064-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 05/31/2021] [Indexed: 01/08/2023]
Abstract
The pandemic created by SARS-CoV-2 has caused a shortage in the supplies of N95 filtering facepiece respirators (FFRs), disposable respirators with at least 95% efficiency to remove non-oily airborne particles, due to increasing cases all over the world. The current article reviewed various possible decontamination methods for FFR reuse including ultraviolet germicidal irradiation (UVGI), hydrogen peroxide vapor (HPV), microwave-generated steam (MGS), hydrogen peroxide gas plasma (HPGP), and 70% or higher ethanol solution. HPV decontamination was effective against bacterial spores (6 log10 reduction of Geobacillus stearothermophilus spores) on FFRs and viruses (> 4 log10 reduction of various types of viruses) on inanimate surfaces, and no degradation of respirator materials and fit has been reported. 70% or higher ethanol decontamination showed high efficacy in inactivation of coronaviruses on inanimate surfaces (> 3.9 log10 reduction) but it was lower on FFRs which filtration efficiency was also decreased. UVGI method had good biocidal efficacy on FFRs (> 3 log10 reduction of H1N1 virus) combined with inexpensive, readily available equipment; however, it was more time-consuming to ensure sufficient reduction in SARS-CoV-2. MGS treatment also provided good viral decontamination on FFRs (> 4 log10 reduction of H1N1 virus) along with less time-intensive process and readily available equipment while inconsistent disinfection on the treated surfaces and deterioration of nose cushion of FFRs were observed. HPGP was a good virucidal system (> 6 log10 reduction of Vesicular stomatitis virus) but filtration efficiency after decontamination was inconsistent. Overall, HPV appeared to be one of the most promising methods based on the high biocidal efficacy on FFRs, preservation of respirator performance after multiple cycles, and no residual chemical toxicity. Nonetheless, equipment cost and time of the HPV process and a suitable operating room need to be considered.
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Affiliation(s)
- Ravinder Thaper
- Samuel Ginn College of Engineering, Auburn University, Auburn, AL, 36849, USA
| | - Brendan Fagen
- Samuel Ginn College of Engineering, Auburn University, Auburn, AL, 36849, USA
| | - Jonghwa Oh
- Department of Environmental Health Sciences, University of Alabama at Birmingham, Birmingham, AL, 35294-0022, USA.
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Ludwig-Begall LF, Wielick C, Jolois O, Dams L, Razafimahefa RM, Nauwynck H, Demeuldre PF, Napp A, Laperre J, Thiry E, Haubruge E. "Don, doff, discard" to "don, doff, decontaminate"-FFR and mask integrity and inactivation of a SARS-CoV-2 surrogate and a norovirus following multiple vaporised hydrogen peroxide-, ultraviolet germicidal irradiation-, and dry heat decontaminations. PLoS One 2021; 16:e0251872. [PMID: 34010337 PMCID: PMC8133425 DOI: 10.1371/journal.pone.0251872] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 05/04/2021] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND As the SARS-CoV-2 pandemic accelerates, the supply of personal protective equipment remains under strain. To combat shortages, re-use of surgical masks and filtering facepiece respirators has been recommended. Prior decontamination is paramount to the re-use of these typically single-use only items and, without compromising their integrity, must guarantee inactivation of SARS-CoV-2 and other contaminating pathogens. AIM We provide information on the effect of time-dependent passive decontamination (infectivity loss over time during room temperature storage in a breathable bag) and evaluate inactivation of a SARS-CoV-2 surrogate and a non-enveloped model virus as well as mask and respirator integrity following active multiple-cycle vaporised hydrogen peroxide (VHP), ultraviolet germicidal irradiation (UVGI), and dry heat (DH) decontamination. METHODS Masks and respirators, inoculated with infectious porcine respiratory coronavirus or murine norovirus, were submitted to passive decontamination or single or multiple active decontamination cycles; viruses were recovered from sample materials and viral titres were measured via TCID50 assay. In parallel, filtration efficiency tests and breathability tests were performed according to EN standard 14683 and NIOSH regulations. RESULTS AND DISCUSSION Infectious porcine respiratory coronavirus and murine norovirus remained detectable on masks and respirators up to five and seven days of passive decontamination. Single and multiple cycles of VHP-, UVGI-, and DH were shown to not adversely affect bacterial filtration efficiency of masks. Single- and multiple UVGI did not adversely affect respirator filtration efficiency, while VHP and DH induced a decrease in filtration efficiency after one or three decontamination cycles. Multiple cycles of VHP-, UVGI-, and DH slightly decreased airflow resistance of masks but did not adversely affect respirator breathability. VHP and UVGI efficiently inactivated both viruses after five, DH after three, decontamination cycles, permitting demonstration of a loss of infectivity by more than three orders of magnitude. This multi-disciplinal approach provides important information on how often a given PPE item may be safely reused.
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Affiliation(s)
- Louisa F. Ludwig-Begall
- Department of Infectious and Parasitic Diseases, Veterinary Virology and Animal Viral Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, Liège, Belgium
| | - Constance Wielick
- Department of Infectious and Parasitic Diseases, Veterinary Virology and Animal Viral Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, Liège, Belgium
| | - Olivier Jolois
- Centexbel Textile Research Centre, Grace-Hollogne, Belgium
| | - Lorène Dams
- Department of Infectious and Parasitic Diseases, Veterinary Virology and Animal Viral Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, Liège, Belgium
| | - Ravo M. Razafimahefa
- Department of Infectious and Parasitic Diseases, Veterinary Virology and Animal Viral Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, Liège, Belgium
| | - Hans Nauwynck
- Laboratory of Virology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | | | - Aurore Napp
- Department of Hospital Pharmacy, The University Hospital Center, Liège University, Liège, Belgium
| | - Jan Laperre
- Centexbel Textile Research Centre, Grace-Hollogne, Belgium
| | - Etienne Thiry
- Department of Infectious and Parasitic Diseases, Veterinary Virology and Animal Viral Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, Liège, Belgium
| | - Eric Haubruge
- TERRA Research Centre, Gembloux Agro-Bio Tech, Liège University, Gembloux, Belgium
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Nasheri N, Harlow J, Chen A, Corneau N, Bidawid S. Survival and Inactivation by Advanced Oxidative Process of Foodborne Viruses in Model Low-Moisture Foods. FOOD AND ENVIRONMENTAL VIROLOGY 2021; 13:107-116. [PMID: 33501613 PMCID: PMC7882587 DOI: 10.1007/s12560-020-09457-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/20/2020] [Indexed: 06/12/2023]
Abstract
Enteric viruses, such as human norovirus (NoV) and hepatitis A virus (HAV), are the major causes of foodborne illnesses worldwide. These viruses have low infectious dose, and may remain infectious for weeks in the environment and food. Limited information is available regarding viral survival and transmission in low-moisture foods (LMF). LMFs are generally considered as ready-to-eat products, which undergo no or minimal pathogen reduction steps. However, numerous foodborne viral outbreaks associated with LMFs have been reported in recent years. The objective of this study was to examine the survival of foodborne viruses in LMFs during 4-week storage at ambient temperature and to evaluate the efficacy of advanced oxidative process (AOP) treatment in the inactivation of these viruses. For this purpose, select LMFs such as pistachios, chocolate, and cereal were inoculated with HAV and the norovirus surrogates, murine norovirus (MNV) and feline calicivirus (FCV), then viral survival on these food matrices was measured over a four-week incubation at ambient temperature, by both plaque assay and droplet-digital RT-PCR (ddRT-PCR) using the modified ISO-15216 method as well as the magnetic bead assay for viral recovery. We observed an approximately 0.5 log reduction in viral genome copies, and 1 log reduction in viral infectivity for all three tested viruses following storage of select inoculated LMFs for 4 weeks. Therefore, the present study shows that the examined foodborne viruses can persist for a long time in LMFs. Next, we examined the inactivation efficacy of AOP treatment, which combines UV-C, ozone, and hydrogen peroxide vapor, and observed that while approximately 100% (4 log) inactivation can be achieved for FCV, and MNV in chocolate, the inactivation efficiency diminishes to approximately 90% (1 log) in pistachios and 70% (< 1 log) in cereal. AOP treatment could therefore be a good candidate for risk reduction of foodborne viruses from certain LMFs depending on the food matrix and surface of treatment.
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Affiliation(s)
- Neda Nasheri
- National Food Virology Reference Centre, Bureau of Microbial Hazards, Food Directorate, Health Canada 251 Sir Frederick Banting Driveway, Ottawa, ON, K1A 0K9, Canada.
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.
| | - Jennifer Harlow
- National Food Virology Reference Centre, Bureau of Microbial Hazards, Food Directorate, Health Canada 251 Sir Frederick Banting Driveway, Ottawa, ON, K1A 0K9, Canada
| | - Angela Chen
- National Food Virology Reference Centre, Bureau of Microbial Hazards, Food Directorate, Health Canada 251 Sir Frederick Banting Driveway, Ottawa, ON, K1A 0K9, Canada
| | - Nathalie Corneau
- National Food Virology Reference Centre, Bureau of Microbial Hazards, Food Directorate, Health Canada 251 Sir Frederick Banting Driveway, Ottawa, ON, K1A 0K9, Canada
| | - Sabah Bidawid
- National Food Virology Reference Centre, Bureau of Microbial Hazards, Food Directorate, Health Canada 251 Sir Frederick Banting Driveway, Ottawa, ON, K1A 0K9, Canada
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12
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Wang Z, Kowal SF, Carslaw N, Kahan TF. Photolysis-driven indoor air chemistry following cleaning of hospital wards. INDOOR AIR 2020; 30:1241-1255. [PMID: 32485006 DOI: 10.1111/ina.12702] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 04/17/2020] [Accepted: 05/19/2020] [Indexed: 05/25/2023]
Abstract
Effective cleaning techniques are essential for the sterilization of rooms in hospitals and industry. No-touch devices (NTDs) that use fumigants such as hydrogen peroxide (H2 O2 ), formaldehyde (HCHO), ozone (O3 ), and chlorine dioxide (OClO) are a recent innovation. This paper reports a previously unconsidered potential consequence of such cleaning technologies: the photochemical formation of high concentrations of hydroxyl radicals (OH), hydroperoxy radicals (HO2 ), organic peroxy radicals (RO2 ), and chlorine radicals (Cl) which can form harmful reaction products when exposed to chemicals commonly found in indoor air. This risk was evaluated by calculating radical production rates and concentrations based on measured indoor photon fluxes and typical fumigant concentrations during and after cleaning events. Sunlight and fluorescent tubes without covers initiated photolysis of all fumigants, and plastic-covered fluorescent tubes initiated photolysis of only some fumigants. Radical formation was often dominated by photolysis of fumigants during and after decontamination processes. Radical concentrations were predicted to be orders of magnitude greater than background levels during and immediately following cleaning events with each fumigant under one or more illumination condition. Maximum predicted radical concentrations (1.3 × 107 molecule cm-3 OH, 2.4 ppb HO2 , 6.8 ppb RO2 and 2.2 × 108 molecule cm-3 Cl) were much higher than baseline concentrations. Maximum OH concentrations occurred with O3 photolysis, HO2 with HCHO photolysis, and RO2 and Cl with OClO photolysis. Elevated concentrations may persist for hours after NTD use, depending on the air change rate and air composition. Products from reactions involving radicals could significantly decrease air quality when disinfectants are used, leading to adverse health effects for occupants.
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Affiliation(s)
- Zixu Wang
- Department of Environment and Geography, University of York, York, UK
| | - Shawn F Kowal
- Department of Chemistry, Syracuse University, Syracuse, NY, USA
| | - Nicola Carslaw
- Department of Environment and Geography, University of York, York, UK
| | - Tara F Kahan
- Department of Chemistry, Syracuse University, Syracuse, NY, USA
- Department of Chemistry, University of Saskatchewan, Saskatoon, SK, Canada
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13
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Caruso AA, Del Prete A, Lazzarino AI. Hydrogen peroxide and viral infections: A literature review with research hypothesis definition in relation to the current covid-19 pandemic. Med Hypotheses 2020; 144:109910. [PMID: 32505069 PMCID: PMC7262503 DOI: 10.1016/j.mehy.2020.109910] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/15/2020] [Accepted: 05/28/2020] [Indexed: 01/10/2023]
Abstract
We reviewed the literature concerning the innate response from nasal and oral epithelial cells and their reaction to hydrogen peroxide (H2O2). Hydrogen peroxide is produced physiologically by oral bacteria and plays a significant role in the balance of oral microecology since it is an important antimicrobial agent. In the epithelial cells, the enzyme superoxide dismutase catalyzes a reaction leading from hydrogen peroxide to the ion superoxide. The induced oxidative stress stimulates a local innate response via activation of the toll-like receptors and the NF-κB. Those kinds of reactions are also activated by viral infections. Virus-induced oxidative stress plays an important role in the regulation of the host immune system and the specific oxidant-sensitive pathway is one of the effective strategies against viral infections. Therefore, nose/mouth/throat washing with hydrogen peroxide may enhance those local innate responses to viral infections and help protect against the current coronavirus pandemic. We strongly encourage the rapid development of randomized controlled trials in both SARS-CoV-2 positive and negative subjects to test the preliminary findings from the in-vitro and in-vivo observational studies that we identified.
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Affiliation(s)
| | - Antonio Del Prete
- Department of Ophthalmology, Università degli studi di Napoli Federico II, Naples, Italy
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14
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Ludwig-Begall LF, Wielick C, Dams L, Nauwynck H, Demeuldre PF, Napp A, Laperre J, Haubruge E, Thiry E. The use of germicidal ultraviolet light, vaporized hydrogen peroxide and dry heat to decontaminate face masks and filtering respirators contaminated with a SARS-CoV-2 surrogate virus. J Hosp Infect 2020; 106:577-584. [PMID: 32889029 PMCID: PMC7462546 DOI: 10.1016/j.jhin.2020.08.025] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 08/26/2020] [Indexed: 01/31/2023]
Abstract
BACKGROUND In the context of the ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, the supply of personal protective equipment remains under severe strain. To address this issue, re-use of surgical face masks and filtering facepiece respirators has been recommended; prior decontamination is paramount to their re-use. AIM We aim to provide information on the effects of three decontamination procedures on porcine respiratory coronavirus (PRCV)-contaminated masks and respirators, presenting a stable model for infectious coronavirus decontamination of these typically single-use-only products. METHODS Surgical masks and filtering facepiece respirator coupons and straps were inoculated with infectious PRCV and submitted to three decontamination treatments, ultraviolet (UV) irradiation, vaporized H2O2, and dry heat treatment. Viruses were recovered from sample materials and viral titres were measured in swine testicle cells. FINDINGS UV irradiation, vaporized H2O2 and dry heat reduced infectious PRCV by more than three orders of magnitude on mask and respirator coupons and rendered it undetectable in all decontamination assays. CONCLUSION This is the first description of stable disinfection of face masks and filtering facepiece respirators contaminated with an infectious SARS-CoV-2 surrogate using UV irradiation, vaporized H2O2 and dry heat treatment. The three methods permit demonstration of a loss of infectivity by more than three orders of magnitude of an infectious coronavirus in line with the United States Food and Drug Administration policy regarding face masks and respirators. It presents advantages of uncomplicated manipulation and utilization in a BSL2 facility, therefore being easily adaptable to other respirator and mask types.
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Affiliation(s)
- L F Ludwig-Begall
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, Liège, Belgium
| | - C Wielick
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, Liège, Belgium
| | - L Dams
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, Liège, Belgium
| | - H Nauwynck
- Laboratory of Virology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - P-F Demeuldre
- Department of Hospital Pharmacy, The University Hospital Center, University of Liège, Liège, Belgium
| | - A Napp
- Department of Hospital Pharmacy, The University Hospital Center, University of Liège, Liège, Belgium
| | - J Laperre
- Centexbel Textile Research Centre, Grace-Hollogne, Belgium
| | - E Haubruge
- TERRA Research Centre, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - E Thiry
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, Liège, Belgium.
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15
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Ortega KL, Rech BDO, Ferreira Costa AL, Perez Sayans M, Braz-Silva PH. Is 0.5% hydrogen peroxide effective against SARS-CoV-2? Oral Dis 2020; 28 Suppl 1:937-939. [PMID: 32564413 PMCID: PMC7323093 DOI: 10.1111/odi.13503] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 12/20/2022]
Affiliation(s)
- Karem López Ortega
- Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil
| | - Bruna de Oliveira Rech
- Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil
| | | | - Mario Perez Sayans
- Oral Medicine Unit, Faculty of Dentistry, Universidad de Santiago de Compostela - Instituto de Investigación Sanitaria (IDIS), Santiago, Spain
| | - Paulo Henrique Braz-Silva
- Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil.,Laboratory of Virology, Institute of Tropical Medicine of São Paulo, School of Medicine, University of São Paulo, São Paulo, Brazil
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16
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Khan MH, Yadav H. Sanitization During and After COVID-19 Pandemic: A Short Review. TRANSACTIONS OF THE INDIAN NATIONAL ACADEMY OF ENGINEERING 2020; 5. [PMCID: PMC7603432 DOI: 10.1007/s41403-020-00177-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Sanitization is a preventive and strategic method to contain the spread of SARS-CoV2. Since there is no foolproof method to tackle the present COVID-19 pandemic, sanitization has a central role to play. The present article briefly reviews various methods of sanitization for individuals, surfaces and ambience. The article reviews different approaches toward sanitization and examines the historicity of the methods employed.
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Affiliation(s)
- Majid Hassan Khan
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, 400076 India
| | - Harekrishna Yadav
- Discipline of Mechanical Engineering, Indian Institute of Technology Indore, Simrol, 453552 India
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17
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Otter J, Yezli S, Barbut F, Perl T. An overview of automated room disinfection systems: When to use them and how to choose them. DECONTAMINATION IN HOSPITALS AND HEALTHCARE 2020. [PMCID: PMC7153347 DOI: 10.1016/b978-0-08-102565-9.00015-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Conventional disinfection methods are limited by reliance on the operator to ensure appropriate selection, formulation, distribution, and contact time of the agent. Automated room disinfection (ARD) systems remove or reduce reliance on operators and so they have the potential to improve the efficacy of terminal disinfection. The most commonly used systems are hydrogen peroxide vapor (H2O2 vapor), aerosolized hydrogen peroxide (aHP), and ultraviolet (UV) light. These systems have important differences in their active agent, delivery mechanism, efficacy, process time, and ease of use. The choice of ARD system should be influenced by the intended application, the evidence base for effectiveness, practicalities of implementation, and cost considerations.
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Affiliation(s)
- J.A. Otter
- NIHR Health Protection Research Unit (HPRU) in HCAIs and AMR at Imperial College London, and Imperial College Healthcare NHS Trust, Infection Prevention and Control, London, United Kingdom
| | - S. Yezli
- Global Centre for Mass Gatherings Medicine, WHO Collaborating Centre for Mass Gatherings Medicine, Ministry of Health-Public Health Directorate, Riyadh, Kingdom of Saudi Arabia
| | - F. Barbut
- National Reference Laboratory for C. difficile, Infection Control Unit, Hôpital Saint Antoine, Paris, France,INSERM S-1139, Faculté de Pharmacie de Paris, Université de Paris, Paris, France
| | - T.M. Perl
- Infectious Diseases and Geographic Medicine, UT Southwestern Medical Center, Dallas, TX, United States
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Holmdahl T, Odenholt I, Riesbeck K, Medstrand P, Widell A. Hydrogen peroxide vapour treatment inactivates norovirus but has limited effect on post-treatment viral RNA levels. Infect Dis (Lond) 2019; 51:197-205. [PMID: 30646786 DOI: 10.1080/23744235.2018.1546056] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
BACKGROUND Hydrogen peroxide vapour is used as a room disinfectant. Its activity against murine norovirus, a surrogate viability marker for human norovirus, indicates that it is also active against human norovirus. AIM The aim of this study is to assess how this effect on viability is reflected in measurements of RNA by quantitative PCR (qPCR). METHODS Faeces suspensions of two human norovirus field strains, genogroup I and II and one cultured murine norovirus strain, (genogroup V) were dried on plastic plates, and underwent hydrogen peroxide vapour treatment or were mock treated. The influence of hydrogen peroxide on RNA was measured on genogroups I, II and V by qPCRs and for the cultivable murine norovirus also for viability by cell culture. Virucidal activity on murine norovirus was measured by endpoint titrations as the 50% tissue culture infectious dose, based both on cytopathic effect and on presence of replicating intracellular minus strand RNA. RESULTS The mean impact on the human norovirus qPCRs was 0.4 log10. The murine norovirus qPCR changed by 1.7 log10 but by an alternative qPCR only by 0.4 log10. These minor changes contrasted the 4.5-5.0 log10 murine norovirus viability reduction after treatment measured by cytopathic effect or intracellular negative-strand RNA. CONCLUSION Inactivation of murine norovirus viability by hydrogen peroxide vapour was not reflected in qPCR levels. This finding might be extrapolated to the related human norovirus genogroups. We further found that cellular minus strand murine norovirus PCR was an observer-independent marker to study reduction of murine norovirus viability.
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Affiliation(s)
- Torsten Holmdahl
- a Infectious Diseases Unit, Department of Translational Medicine , Lund University , Malmö , Sweden
| | - Inga Odenholt
- a Infectious Diseases Unit, Department of Translational Medicine , Lund University , Malmö , Sweden
| | - Kristian Riesbeck
- b Clinical Microbiology, Department of Translational Medicine , Lund University , Malmö , Sweden
| | - Patrik Medstrand
- c Clinical Virology, Department of Translational Medicine , Lund University , Lund , Sweden
| | - Anders Widell
- c Clinical Virology, Department of Translational Medicine , Lund University , Lund , Sweden
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