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1.
Microbes Infect ; : 105150, 2023 May 11.
Article in English | MEDLINE | ID: covidwho-2315955

ABSTRACT

Viral infection treatment is a difficult task due to its complex structure and metabolism. Additionally, viruses can alter the metabolism of host cells, mutate, and readily adjust to harsh environments. Coronavirus stimulates glycolysis, weakens mitochondrial activity, and impairs infected cells. In this study, we investigated the efficacy of 2-DG in inhibiting coronavirus-induced metabolic processes and antiviral host defense systems, which have not been explored so far. 2-Deoxy-d-glucose (2-DG), a molecule restricting substrate availability, has recently gained attention as a potential antiviral drug. The results revealed that 229E human coronavirus promoted glycolysis, producing a significant increase in the concentration of fluorescent 2-NBDG, a glucose analog, particularly in the infected host cells. The addition of 2-DG decreased its viral replication and suppressed infection-induced cell death and cytopathic effects, thereby improving the antiviral host defense response. It was also observed that administration of low doses of 2-DG inhibited glucose uptake, indicating that 2-DG consumption in virus-infected host cells was mediated by high-affinity glucose transporters, whose levels were amplified upon coronavirus infection. Our findings indicated that 2-DG could be a potential drug to improve the host defense system in coronavirus-infected cells.

2.
ACS ES and T Engineering ; 2023.
Article in English | Scopus | ID: covidwho-2298950

ABSTRACT

As COVID-19 and other infectious diseases continue to spread globally, removing airborne pathogens from confined spaces such as buildings, transportation carriers, and stations is becoming increasingly crucial to curbing transmission and reducing human infection rates. Bioaerosols can act as vectors or media that could store and transport air pollutants and pathogens. To mitigate the adverse effects of bioaerosols and effectively control epidemics, this work reviews the current state-of-the-art air purification processes and technologies available on the market or demonstrated in laboratory and industrial settings, including ozone oxidation, UV disinfection, and photocatalysis. These reactive air purification processes can be used in conjunction with adsorption or filtration-based systems to enhance disinfection besides the physical capture of particulates or the removal of volatile organic compounds (VOCs). This review aims to provide a concise yet comprehensive overview of various reactive air purification technologies. Their principles, applications, and limitations are briefly discussed to provide insight and guidelines for further development of new air purification processes to address emerging airborne contaminant issues. © 2023 American Chemical Society.

3.
Biotechnol Lett ; 45(4): 551-561, 2023 Apr.
Article in English | MEDLINE | ID: covidwho-2271310

ABSTRACT

PURPOSE: We examined the inactivation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by a nitrogen-doped titanium dioxide (N-TiO2) visible-light photocatalyst that was activated via light irradiation in the natural environment and was safe for human use as a coating material. METHODS: The photocatalytic activity of glass slides coated with three types of N-TiO2 without metal or loaded with copper or silver and copper was investigated by measuring acetaldehyde degradation. The titer levels of infectious SARS-CoV-2 were measured using cell culture after exposing photocatalytically active coated glass slides to visible light for up to 60 min. RESULTS: N-TiO2 photoirradiation inactivated the SARS-CoV-2 Wuhan strain and this effect was enhanced by copper loading and further by the addition of silver. Hence, visible-light irradiation using silver and copper-loaded N-TiO2 inactivated the Delta, Omicron, and Wuhan strains. CONCLUSION: N-TiO2 could be used to inactivate SARS-CoV-2 variants, including emerging variants, in the environment.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , Nitrogen Dioxide , Silver , Copper , Light , Titanium/radiation effects , Nitrogen , Catalysis
4.
J Occup Environ Hyg ; : 1-20, 2022 Oct 18.
Article in English | MEDLINE | ID: covidwho-2281698

ABSTRACT

In emergencies like the COVID-19 pandemic, reuse or reprocessing of filtering facepiece respirators (FFRs) may be required to mitigate exposure risk. Research gap: Only a few studies evaluated decontamination effectiveness against SARS-CoV-2 that are practical for low-resource settings. This study aimed to determine the effectiveness of a relatively inexpensive ultraviolet germicidal irradiation chamber to decontaminate FFRs contaminated with SARS-CoV-2. A custom design UVGI chamber was constructed to determine the ability to decontaminate seven FFR models including N95s, KN95 and FFP2s inoculated with SARS-CoV-2. Vflex was excluded due to design folds/pleats and UVGI shadowing inside the chamber. Structural and functional integrity tolerated by each FFR model on repeated decontamination cycles was assessed. Twenty-seven participants were fit tested over 30 cycles for each model and passed if the fit factor was ≥100. Of the FFR models included for testing, only the KN95 model failed filtration. The 3M™ 3M 1860 and Halyard™ duckbill 46727 (formerly Kimberly Clark) models performed better on fit testing than other models for both pre-and-post decontaminations. Fewer participants (0.3 and 0.7%, respectively) passed fit testing for Makrite 9500 N95 and Greenline 5200 FFP2 and only two for the KN95 model post decontamination. Fit testing appeared to be more affected by donning & doffing, as some passed with adjustment and repeat fit testing. A ≥ 3 log reduction of SARS-CoV-2 was achieved for worn-in FFRs namely Greenline 5200 FFP2. Conclusion: The study showed that not all FFRs tested could withstand 30 cycles of UVGI decontamination without diminishing filtration efficiency or facial fit. In addition, SARS-CoV-2 log reduction varied across the FFRs, implying that the decontamination efficacy largely depends on the decontamination protocol and selection of FFRs. We demonstrated the effectiveness of a low-cost and scalable decontamination method for SARS-CoV-2 and the effect on fit testing using people instead of manikins. It is recognised that extensive experimental evidence for the reuse of decontaminated FFRs is lacking, and thus this study would be relevant and of interest in crisis-capacity settings, particularly in low-resource facilities.

5.
Biometals ; 2022 Dec 07.
Article in English | MEDLINE | ID: covidwho-2260756

ABSTRACT

SARS-CoV-2 is a highly infectious virus and etiologic agent of COVID-19, which is spread by respiratory droplets, aerosols, and contaminated surfaces. Copper is a known antiviral agent, and has resulted in successful reduction of pathogens and infections by 83-99.9% when coated on surfaces in intensive care units. Additionally, copper has been shown to inactivate pathogens such as Coronavirus 226E, a close relative of SARS-CoV-2. Here, we examine the ability of two copper blends with differing compositions to inactivate SARS-CoV-2 virus at different time points. Copper Blend 2 (75.07% pure copper) was found to significantly reduce (over 50%) the viability of SARS-CoV-2 at 5 min of contact, with at least 98% reduction in recovered virus at 20 min (vs. plastic control). However, Copper Blend 1 (48.26% pure copper), was not found to significantly reduce viability of SARS-CoV-2 at any time point when compared to plastic. This may indicate that there is an important percentage of copper content in materials that is needed to effectively inactivate SARS-CoV-2. Overall, this study shows that over the course of 20 min, coatings made of copper materials can significantly reduce the recovery of infectious SARS-CoV-2 compared to uncoated controls, indicating the effective use of copper for viral inactivation on surfaces. Furthermore, it may suggest higher copper content has stronger antiviral properties. This could have important implications when short turnaround times are needed for cleaning and disinfecting rooms or equipment, especially in strained healthcare settings which are struggling to keep up with demand.

6.
Biochim Biophys Acta Biomembr ; 1865(4): 184136, 2023 04.
Article in English | MEDLINE | ID: covidwho-2234188

ABSTRACT

A recent study provided experimental evidence of inactivation of viral activity after radio-frequency (RF) exposures in the 6-12 GHz band that was hypothesized to be caused by vibrations of an acoustic dipole mode in the virus that excited the viral membrane to failure. Here, we develop an atomic-scale molecular dynamics (MD) model of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral surface to estimate the electric fields necessary to rupture the viral membrane via dipole shaking of the virus. We computed the absorption spectrum of the system via unbiased MD simulations and found no particular strong absorption in the GHz band. We investigated the mechanical resiliency of the viral membrane by introducing uniaxial strains in the system and observed no pore formation in the membrane for strains up to 50%. Because the computed absorption spectrum was found to be essentially flat, and the strain required to break the viral membrane was >0.5, the field strength associated with rupture of the virus was greater than the dielectric breakdown value of air. Thus, RF disinfection of enveloped viruses would occur only once sufficient heat was transferred to the virus via a thermal mechanism and not by direct action (shaking) of the RF field oscillations on the viral membrane.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Models, Molecular
7.
Journal of Hazardous Materials Advances ; : 100217, 2022.
Article in English | ScienceDirect | ID: covidwho-2158889

ABSTRACT

The unprecedented situation of the COVID-19 pandemic heavily polluted water bodies whereas the presence of SARS-CoV-2, even in treated wastewater in every corner of the world is reported. The main aim of the present study is to show the effectiveness and feasibility of some well-known desalination technologies which are reverse osmosis (RO), Electrodialysis (ED), Membrane Distillation (MD), multi effect distillation (MED), and multi stage flashing (MSF) during the COVID-19 pandemic. Systems' effectiveness against the novel coronavirus based on three parameters of nasopharynx/nasal saline-irrigation, temperature of operation and pretreatment methods are evaluated. First, based on previous clinical studies, it showed that using saline solution (hypertonic saline >0.9% concentration) for gargling/irrigating of nasal/nasopharynx/throat results in reducing and replication of the viral in patients, subsequently the feed water of desalination plants which has concentration higher than 3.5% (35000ppm) is preventive against the SARS-CoV-2 virus. Second, the temperature operation of thermally-driven desalination;MSF and MED (70-120°C) and MD (55-85°C) is high enough to inhibit the contamination of plant structure and viral survival in feed water. The third factor is utilizing various pretreatment process such as chlorination, filtration, thermal/precipitation softening, ultrafiltration (mostly for RO, but also for MD, MED and MSF), which are powerful treatment methods against biologically-contaminated feed water particularly the SARS-CoV-2. Eventually, it can be concluded that large-scale desalination plants during COVID-19 and similar situation are completely reliable for providing safe drinking water.

8.
Revista Cubana de Medicina Tropical ; 74(2) (no pagination), 2022.
Article in Spanish | EMBASE | ID: covidwho-2147758

ABSTRACT

Introduction: Collection media of clinical samples with the capacity to denature viruses reduce the risk of contagion during transportation and processing. Objective(s): To use the nucleic acids transport media (NATM) in nasopharyngeal swab samples collected for the diagnosis of SARS-CoV-2. Method(s): An experimental study was conducted to demonstrate the medium capacity to inactivate viral infectivity. Zika virus (ZIKV), of biosafety level 2, was used as an enveloped virus model. The clinical performance of the NATM for the diagnosis of SARS-CoV-2 was evaluated. A ZIKV strain propagated in the Vero cell line was used and, prior to cells infection, ZIKV was in contact at different intervals (2;15, and 30 min) with pure NATM;subsequently, serial dilutions (10-1-10-4) were performed. Viral inactivation was evaluated by RT-PCR in the supernatant and the collected cells when the propagation period was completed. CITOSWAB VTM was used as reference to estimate the clinical performance of the NATM in 30 nasopharyngeal swabs collected for the diagnosis of SARS-CoV-2 infection. Result(s): ZIKV remained infectious at inoculum dilutions of >= 10-2, regardless of contact time. Clinical specificity and sensitivity of the NATM for the diagnosis of SARS-CoV-2 were 100%, respectively. Conclusion(s): Results suggest that ZIKV positive clinical samples at dilutions <= 10-1 of the NATM can be safely handled, which could potentially be applied to the molecular diagnosis of SARS-CoV-2. Copyright © 2022, Editorial Ciencias Medicas. All rights reserved.

9.
Viruses ; 14(12)2022 11 30.
Article in English | MEDLINE | ID: covidwho-2143725

ABSTRACT

The coronavirus disease (COVID-19) pandemic has placed a massive impact on global civilization. Finding effective treatments and drugs for these viral diseases was crucial. This paper outlined and highlighted key elements of recent advances in nonthermal biocompatible plasma (NBP) technology for antiviral applications. We searched for papers on NBP virus inactivation in PubMed ePubs, Scopus, and Web of Science databases. The data and relevant information were gathered in order to establish a mechanism for NBP-based viral inactivation. NBP has been developed as a new, effective, and safe strategy for viral inactivation. NBP may be used to inactivate viruses in an ecologically friendly way as well as activate animal and plant viruses in a number of matrices. The reactive species have been shown to be the cause of viral inactivation. NBP-based disinfection techniques provide an interesting solution to many of the problems since they are simply deployable and do not require the resource-constrained consumables and reagents required for traditional decontamination treatments. Scientists are developing NBP technology solutions to assist the medical community in dealing with the present COVID-19 outbreak. NBP is predicted to be the most promising strategy for battling COVID-19 and other viruses in the future.


Subject(s)
COVID-19 , Plant Viruses , Virus Diseases , Animals , SARS-CoV-2 , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Virus Diseases/drug therapy , Virus Inactivation
10.
Curr Issues Mol Biol ; 44(11): 5666-5690, 2022 Nov 15.
Article in English | MEDLINE | ID: covidwho-2116060

ABSTRACT

Global society has been highly pressured by the COVID-19 pandemic, which has exposed vulnerabilities in supply chains for disinfection products, personal protective equipment, and medical resources worldwide. It is critically necessary to find effective treatments and medications for these viral infections. This review summarizes and emphasizes critical features of recent breakthroughs in vaccines, inhibitors, radiations, and innovative nonthermal atmospheric plasma (NTAP) technologies to inactivate COVID-19. NTAP has emerged as an effective, efficient, and safe method of viral inactivation. NTAP can be used to inactivate viruses in an environmentally friendly manner, as well as activate animal and plant viruses in a variety of matrices. Researchers and engineers desire to help the medical world deal with the ongoing COVID-19 epidemic by establishing techniques that make use of widely available NTAP technologies. NTAP technology is not dependent on viral strain, and it does not necessitate months or years of research to develop specific vaccines for each novel or arising viral disease. We believe the NTAP is a highly promising technique for combating COVID-19 and other viruses. Thus, NTAP technology could be a significant breakthrough in the near future in assisting humans in combating COVID-19 infections. We hope that this review provides a platform for readers to examine the progress made in the fight against COVID-19 through the use of vaccines, inhibitors, radiation, and NTAP.

11.
Journal of Molecular Liquids ; 366, 2022.
Article in English | Scopus | ID: covidwho-2049679

ABSTRACT

An innovative sonication method has been developed to produce inclusion complexes (ICs) of Oseltamivir (OTV) which is a potentially water-soluble anti-viral agent with lesser cytotoxicity. Proton signals and chemical shifts of OTV without any ambiguity confirm the formation of ICs with β-Cyclodextrin (B-CD) and Hydroxypropyl-β-cyclodextrin (H-CD). ICs are also supported by their atomic percentages as secondary evidence using XPS analysis. Analysis of drug release at three pH levels revealed the slow release of the OTV from ICs and also suitable for viral inactivation. A very less cytotoxic ability on cancer cell lines and enhanced the viral inactivation of OTV after being made into water-soluble ICs. © 2022 Elsevier B.V.

12.
Reference Module in Food Science ; 2023.
Article in English | ScienceDirect | ID: covidwho-2041388

ABSTRACT

Concerns over whether people can be infected with SARS-CoV-2 from food and packaging have caused significant disruption to global food trade. SARS-CoV-2, the virus that causes COVID-19, can remain infectious and detectable on packaging or some foods under certain cold-chain conditions. However, there is minimal evidence that people have been infected with SARS-CoV-2 from packaging or from foodborne transmission. Cooking of food will inactivate the virus. Any infectious SARS-CoV-2 present in consumed food would likely be inactivated by stomach acid. Nonetheless, good food hygiene practices are sensible precautions to minimize any possibility of food or packaging acting as a vector for SARS-CoV-2.

13.
Drug Discov Today ; 27(10): 103330, 2022 Oct.
Article in English | MEDLINE | ID: covidwho-1966493

ABSTRACT

Among explored nanomaterials, nanosponge-based systems have exhibited inhibitory effects for the biological neutralization of, and antiviral delivery against, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More studies could pave the path for clarification of their biological neutralization mechanisms as well as the assessment of their long-term biocompatibility and biosafety issues before clinical translational studies. In this review, we discuss recent advances pertaining to antiviral delivery and inhibitory effects of nanosponges against SARS-CoV-2, focusing on important challenges and opportunities. Finally, as promising approaches for recapitulating the complex structure of different organs/tissues of the body, we discuss the use of 3D in vitro models to investigate the mechanism of SARS-CoV-2 infection and to find therapeutic targets to better manage and eradicate coronavirus 2019 (COVID-19).


Subject(s)
COVID-19 Drug Treatment , SARS-CoV-2 , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Humans
14.
J Photochem Photobiol B ; 234: 112531, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-1956241

ABSTRACT

The SARS-CoV-2 pandemic emphasized effective cleaning and disinfection of common spaces as an essential tool to mitigate viral transmission. To address this problem, decontamination technologies based on UV-C light are being used. Our aim was to generate coherent and translational datasets of effective UV-C-based SARS-CoV-2 inactivation protocols for the application on surfaces with different compositions. Virus infectivity after UV-C exposure of several porous (bed linen, various types of upholstery, synthetic leather, clothing) and non-porous (types of plastic, stainless steel, glass, ceramics, wood, vinyl) materials was assessed through plaque assay using a SARS-CoV-2 clinical isolate. Studies were conducted under controlled environmental conditions with a 254-nm UV-C lamp and irradiance values quantified using a 254 nm-calibrated sensor. From each material type (porous/non-porous), a product was selected as a reference to assess the decrease of infectious virus particles as a function of UV-C dose, before testing the remaining surfaces with selected critical doses. Our data show that UV-C irradiation is effectively inactivating SARS-CoV-2 on both material types. However, an efficient reduction in the number of infectious viral particles was achieved much faster and at lower doses on non-porous surfaces. The treatment effectiveness on porous surfaces was demonstrated to be highly variable and composition-dependent. Our findings will support the optimization of UV-C-based technologies, enabling the adoption of effective customizable protocols that will help to ensure higher antiviral efficiencies.


Subject(s)
COVID-19 , SARS-CoV-2 , Disinfection/methods , Humans , Pandemics , Ultraviolet Rays , Virus Inactivation
15.
Life (Basel) ; 12(7)2022 Jun 30.
Article in English | MEDLINE | ID: covidwho-1917599

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is evolving, with emergence of mutational variants due to the error-prone replication process of RNA viruses, in general. More recently, the Delta and Omicron variants (including sub-variants BA.1-5) predominate globally, and a Delta-Omicron recombinant termed Deltacron has emerged. The emergence of variants of concern (VOC) demonstrating immune evasion and potentially greater transmissibility and virulence naturally raises concern in both the infection control communities and the public at large, as to the continued suitability of interventions intended to mitigate the risk of viral dissemination and acquisition of the associated disease COVID-19. We evaluated the virucidal efficacy of targeted surface hygiene products (an ethanol/quaternary ammonium compound (QAC)-containing disinfectant spray, a QAC disinfectant wipe, a lactic acid disinfectant wipe, and a citric acid disinfectant wipe) through both theoretical arguments and empirical testing using international standard methodologies (ASTM E1053-20 hard surface test and EN14476:2013+A2:2019 suspension test) in the presence of soil loads simulating patients' bodily secretions/excretions containing shed virus. The results demonstrate, as expected, complete infectious viral inactivation (≥3.0 to ≥4.7 log10 reduction in infectious virus titer after as little as 15 s contact time at room temperature) by these surface hygiene agents of the original SARS-CoV-2 isolate and its Beta and Delta VOC. Through appropriate practices of targeted surface hygiene, it is expected that irrespective of the SARS-CoV-2 VOC encountered as the current pandemic unfolds (and, for that matter, any emerging and/or re-emerging enveloped virus), the chain of infection from virus-contaminated fomites to the hand and mucous membranes of a susceptible person may be disrupted.

16.
Bioactive Materials ; 2022.
Article in English | ScienceDirect | ID: covidwho-1821146

ABSTRACT

The ongoing pandemic caused by the novel coronavirus, SARS-CoV-2, is influencing global health. Moreover, there is a major threat of future coronaviruses affecting the entire world in a similar, or even more dreadful, manner. Therefore, effective and biocompatible therapeutic options against coronaviruses are urgently needed. To address this challenge, medical specialists require a well-informed and safe approach to treating human coronaviruses (HCoVs). Herein, an environmental friendly approach for viral inactivation, based on plasma technology, was considered. A microwave plasma system was employed for the generation of the high amount of gaseous nitric oxide to prepare nitric oxide enriched plasma-activated water (NO-PAW), the effects of which on coronaviruses, have not been reported to date. To determine these effects, alpha-HCoV-229E was used in an experimental model. We found that NO-PAW treatment effectively inhibited coronavirus infection in host lung cells, visualized by evaluating the cytopathic effect and expression level of spike proteins. Interestingly, NO-PAW showed minimal toxicity towards lung host cells, suggesting its potential for therapeutic application. Moreover, this new approach resulted in viral inactivation and greatly improved the gene levels involved in host antiviral responses. Together, our findings provide evidence of an initiation point for further progress toward the clinical development of antiviral treatments, including such coronaviruses.

17.
Pharmaceutics ; 14(3)2022 Mar 21.
Article in English | MEDLINE | ID: covidwho-1753663

ABSTRACT

Different light-based strategies have been investigated to inactivate viruses. Herein, we developed an HIV-based pseudotyped model of SARS-CoV-2 (SC2) to study the mechanisms of virus inactivation by using two different strategies; photoinactivation (PI) by UV-C light and photodynamic inactivation (PDI) by Photodithazine photosensitizer (PDZ). We used two pseudoviral particles harboring the Luciferase-IRES-ZsGreen reporter gene with either a SC2 spike on the membrane or without a spike as a naked control pseudovirus. The mechanism of viral inactivation by UV-C and PDZ-based PDI were studied via biochemical characterizations and quantitative PCR on four levels; free-cell viral damage; viral cell entry; DNA integration; and expression of reporter genes. Both UV-C and PDZ treatments could destroy single stranded RNA (ssRNA) and the spike protein of the virus, with different ratios. However, the virus was still capable of binding and entering into the HEK 293T cells expressing angiotensin-converting enzyme 2 (ACE-2). A dose-dependent manner of UV-C irradiation mostly damages the ssRNA, while PDZ-based PDI mostly destroys the spike and viral membrane in concentration and dose-dependent manners. We observed that the cells infected by the virus and treated with either UV-C or PDZ-based PDI could not express the luciferase reporter gene, signifying the viral inactivation, despite the presence of RNA and DNA intact genes.

18.
J Environ Chem Eng ; 10(3): 107527, 2022 Jun.
Article in English | MEDLINE | ID: covidwho-1729898

ABSTRACT

Coronavirus disease-2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been one of the most challenging worldwide epidemics of recent times. Semiconducting materials (photocatalysts) could prove effectual solar-light-driven technology on account of variant reactive oxidative species (ROS), including superoxide (•O2 - ) and hydroxyl (•OH) radicals either by degradation of proteins, DNA, RNA, or preventing cell development by terminating cellular membrane. Graphene-based materials have been exquisitely explored for antiviral applications due to their extraordinary physicochemical features including large specific surface area, robust mechanical strength, tunable structural features, and high electrical conductivity. Considering that, the present study highlights a perspective on the potentials of graphene based materials for photocatalytic antiviral activity. The interaction of virus with the surface of graphene based nanomaterials and the consequent physical, as well as ROS induced inactivation process, has been highlighted and discussed. It is highly anticipated that the present review article emphasizing mechanistic antiviral insights could accelerate further research in this field.

19.
Pathogens ; 10(12)2021 Dec 08.
Article in English | MEDLINE | ID: covidwho-1554997

ABSTRACT

Blue LED light has proven to have a powerful bacteria-killing ability; however, little is known about its mechanism of virucidal activity. Therefore, we analyzed the effect of blue light on different respiratory viruses, such as adenovirus, respiratory syncytial virus and SARS-CoV-2. The exposure of samples to a blue LED light with a wavelength of 420 nm (i.e., in the visible range) at 20 mW/cm2 of irradiance for 15 min appeared optimal and resulted in the complete inactivation of the viral load. These results were similar for all the three viruses, demonstrating that both enveloped and naked viruses could be efficiently inactivated with blue LED light, regardless of the presence of envelope and of the viral genome nature (DNA or RNA). Moreover, we provided some explanations to the mechanisms by which the blue LED light could exert its antiviral activity. The development of such safe and low-cost light-based devices appears to be of fundamental utility for limiting viral spread and for sanitizing small environments, objects and surfaces, especially in the pandemic era.

20.
mSystems ; 6(5): e0067421, 2021 Oct 26.
Article in English | MEDLINE | ID: covidwho-1508358

ABSTRACT

The global emergence of novel pathogenic viruses presents an important challenge for research, as high biosafety levels are required to process samples. While inactivation of infectious agents facilitates the use of less stringent safety conditions, its effect on other biological entities of interest present in the sample is generally unknown. Here, we analyzed the effect of five inactivation methods (heat, ethanol, formaldehyde, psoralen, and TRIzol) on microbiome composition and diversity in samples collected from four different body sites (gut, nasal, oral, and skin) and compared them against untreated samples from the same tissues. We performed 16S rRNA gene sequencing and estimated abundance and diversity of bacterial taxa present in all samples. Nasal and skin samples were the most affected by inactivation, with ethanol and TRIzol inducing the largest changes in composition, and heat, formaldehyde, TRIzol, and psoralen inducing the largest changes in diversity. Oral and stool microbiomes were more robust to inactivation, with no significant changes in diversity and only moderate changes in composition. Firmicutes was the taxonomic group least affected by inactivation, while Bacteroidetes had a notable enrichment in nasal samples and moderate enrichment in fecal and oral samples. Actinobacteria were more notably depleted in fecal and skin samples, and Proteobacteria exhibited a more variable behavior depending on sample type and inactivation method. Overall, our results demonstrate that inactivation methods can alter the microbiome in a tissue-specific manner and that careful consideration should be given to the choice of method based on the sample type under study. IMPORTANCE Understanding how viral infections impact and are modulated by the microbiome is an important problem in basic research but is also of high clinical relevance under the current pandemic. To facilitate the study of interactions between microbial communities and pathogenic viruses under safe conditions, the infectious agent is generally inactivated prior to processing samples. The effect of this inactivation process in the microbiome is, however, unknown. Further, it is unclear whether biases introduced by inactivation methods are dependent on the sample type under study. Estimating the magnitude and nature of the changes induced by different methods in samples collected from various body sites thus provides important information for current and future studies that require inactivation of pathogenic agents.

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