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1.
Proc Biol Sci ; 287(1931): 20200610, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-33043868

RESUMO

To harvest energy from chemical reactions, microbes engage in diverse catabolic interactions that drive material cycles in the environment. Here, we consider a simple mathematical model for cycling reactions between alternative forms of an element (A and Ae), where reaction 1 converts A to Ae and reaction 2 converts Ae to A. There are two types of microbes: type 1 microbes harness reaction 1, and type 2 microbes harness reaction 2. Each type receives its own catabolic resources from the other type and provides the other type with the by-products as the catabolic resources. Analyses of the model show that each type increases its steady-state abundance in the presence of the other type. The flux of material flow becomes faster in the presence of microbes. By coupling two catabolic reactions, types 1 and 2 can also expand their realized niches through the abundant resource premium, the effect of relative quantities of products and reactants on the available chemical energy, which is especially important for microbes under strong energetic limitations. The plausibility of mutually beneficial interactions is controlled by the available chemical energy (Gibbs energy) of the system. We conclude that mutualistic catabolic interactions can be an important factor that enables microbes in subsurface ecosystems to increase ecosystem productivity and expand the ecosystem.


Assuntos
Fenômenos Ecológicos e Ambientais , Ecossistema , Microbiologia Ambiental
2.
J Zhejiang Univ Sci B ; 21(9): 749-751, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32893532

RESUMO

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was found initially in Wuhan, China in early December 2019. The pandemic has spread to 216 countries and regions, infecting more than 23310 000 people and causing over 800 000 deaths globally by Aug. 24, 2020, according to World Health Organization (https://www.who.int/emergencies/diseases/ novel-coronavirus-2019). Fever, cough, and dyspnea are the three common symptoms of the condition, whereas the conventional transmission route for SARS-CoV-2 is through droplets entering the respiratory tract. To date, infection control measures for COVID-19 have been focusing on the involvement of the respiratory system. However, ignoring potential faecal transmission and the gastrointestinal involvement of SARS-CoV-2 may result in mistakes in attempts to control the pandemic.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Fezes/virologia , Gastroenteropatias/virologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Betacoronavirus/genética , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Microbiologia Ambiental , Humanos , Modelos Biológicos , Pandemias , Pneumonia Viral/epidemiologia , RNA Viral/análise , RNA Viral/genética , Eliminação de Partículas Virais
3.
Eur Rev Med Pharmacol Sci ; 24(17): 9202-9207, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32965015

RESUMO

OBJECTIVE: SARS-CoV-2 can reportedly exist on inanimate surfaces for a long duration, but there is limited data available from Italian COVID-19 hospital wards, especially for non-intensive care units hosting patients that do not require mechanical ventilation. Identification of the extent of environmental contamination can help in understanding possible virus transmission routes, limit hospital infections and protect healthcare workers. Thus, we investigated virus contamination on surfaces of the acute COVID-19 ward of an Italian hospital. MATERIALS AND METHODS: Ward surfaces, including four points inside and six points outside the patients' rooms were sampled by swabs, seven hours after routine sanitation. To minimize the risk of underestimation of virus detection, two different sensitive molecular methods were used comparatively, and specific internal controls were added to enhance the efficiency of all the analysis steps. RESULTS: SARS-CoV-2 contamination was detected in only three out of all the collected samples, i.e., on two floors and one-bathroom sink, likely reflecting aerosol and saliva contamination, respectively. The overall level of contamination was low, and the floors exhibited a very low level of SARS-CoV-2 presence, evidenced by only one of the two methods used. CONCLUSIONS: The existence of SARS-CoV-2 on hospital surfaces may be limited, although it was reported to persist for a longer duration on surfaces under controlled laboratory conditions. Thus, effective transmission of SARS-CoV-2 by surfaces/fomites within the hospital ward may be a rare event. However, the results highlight the importance of assessing method sensitivity and including controls when investigating low-level virus contamination so as to avoid the risk of underestimation of virus presence.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , RNA Viral/metabolismo , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Desinfecção , Microbiologia Ambiental , Contaminação de Equipamentos , Hospitais , Humanos , Itália , Pneumonia Viral/virologia , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real , Risco
4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(8): 1345-1351, 2020 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-32867448

RESUMO

Objective: To analyze the genomic characteristics of human infection with H9N2 avian influenza virus in Gansu province. Methods: The etiological analysis was conducted for human infection with H9N2 avian influenza virus detected in influenza like illness cases in northwestern China in 2016. Molecular bioinformatics Mega 7.0 software was used to analyze the full genomic sequences of the viral isolate. Results: The gene fragments of HA, NA, MP, NP, NS, PA, PB1 and PB2 of the isolate were highly similar (>90%) to those of H9N2 avian influenza virus strain isolated in external environment in Gansu from 2014 to 2019. The HA gene belonged to BJ/94-like branch, PB2 and MP belonged to G1/97-like branch, and the PB1, PA, NS, and NP genes belonged to F/98-like branch. MP and PB2 were closely related to H7N9, H10N8 and H5N6 viruses. Amino acid sequence alignment showed that the HA cleavage site was arranged in PSRSSR ↓ GLF, H183N and Q226L mutated which included 7 HA glycosylated sites; 62-64 sites of NA absented 3 amino acids (ITE); and M2-31N, NS1-42S, PA-356R, and PA-409N mutated. Conclusions: Apparently, this case of human infection with human infection with H9N2 avian influenza virus was an incidental. However, the isolates of H9N2 influenza virus in external environment of Gansu had a series of mammalian adaptive molecular markers, suggesting that the risk of human infection is higher. It is necessary to strengthen the surveillance by multi departments to deal with influenza pandemic.


Assuntos
Vírus da Influenza A Subtipo H9N2/genética , Influenza Humana/virologia , China/epidemiologia , Microbiologia Ambiental , Humanos , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Influenza Humana/epidemiologia
5.
BMC Public Health ; 20(1): 1202, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32758198

RESUMO

BACKGROUND: More than 2 months have passed since the novel coronavirus disease 2019 (COVID-19) first emerged in Wuhan, China. With the migration of people, the epidemic has rapidly spread within China and throughout the world. Due to the severity of the epidemic, undiscovered transmission of COVID-19 deserves further investigation. The aim of our study hypothesized possible modes of SARS-CoV-2 transmission and how the virus may have spread between two family clusters within a residential building in Guangzhou, China. METHODS: In a cross-sectional study, we monitored and traced confirmed patients and their close contacts from January 11 to February 5, 2020 in Guangzhou, China, including 2 family cluster cases and 61 residents within one residential building. The environmental samples of the building and the throat swabs from the patients and from their related individuals were collected for SARS-CoV-2 and tested with real-time reverse transcriptase polymerase chain reaction (RT-PCR). The relevant information was collected and reported using big data tools. RESULTS: There were two notable family cluster cases in Guangzhou, which included 3 confirmed patients (family No.1: patient A, B, C) and 2 confirmed patients (family No.2: patient D, E), respectively. None of patients had contact with other confirmed patients before the onset of symptoms, and only patient A and patient B made a short stop in Wuhan by train. Home environment inspection results showed that the door handle of family No.1 was positive of SARS-CoV-2. The close contacts of the 5 patients all tested negative of SARS-CoV-2 and in good health, and therefore were released after the official medical observation period of 14-days. Finally, according to the traceability investigation through applying big data analysis, we found an epidemiological association between family No.1 and family No.2, in which patient D (family No.2) was infected through touching an elevator button contaminated by snot with virus from patient A (family No.1) on the same day. CONCLUSIONS: Contaminants with virus from confirmed patients can pollute the environment of public places, and the virus can survive on the surface of objects for a short period of time. Therefore, in addition to the conventional droplet transmission, there is also indirect contact transmission such as snot-oral transmission that plays a crucial role in community spread of the virus.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Família , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Adulto , Idoso , China/epidemiologia , Análise por Conglomerados , Busca de Comunicante , Estudos Transversais , Microbiologia Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Reação em Cadeia da Polimerase em Tempo Real , Características de Residência
6.
PLoS One ; 15(8): e0233325, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756562

RESUMO

Antibiotics discovery was a significant breakthrough in the field of therapeutic medicines, but the over (mis)use of such antibiotics (in parallel) caused the increasing number of resistant bacterial species at an ever-higher rate. This study was thus devised to assess the multi-drug resistant bacteria present in sanitation-related facilities in human workplaces. In this regard, samples were collected from different gender, location, and source-based facilities, and subsequent antibiotic sensitivity testing was performed on isolated bacterial strains. Four classes of the most commonly used antibiotics i.e., ß-lactam, Aminoglycosides, Macrolides, and Sulphonamides, were evaluated against the isolated bacteria. The antibiotic resistance profile of different (70) bacterial strains showed that the antibiotic resistance-based clusters also followed the grouping based on their isolation sources, mainly the gender. Twenty-three bacterial strains were further selected for their 16s rRNA gene based molecular identification and for phylogenetic analysis to evaluate the taxonomic evolution of antibiotic resistant bacteria (ARB). Moreover, the bacterial resistance to Sulphonamides and beta lactam was observed to be the most and to Aminoglycosides and macrolides as the least. Plasmid curing was also performed for multidrug resistant (MDR) bacterial strains, which significantly abolished the resistance potential of bacterial strains for different antibiotics. These curing results suggested that the antibiotic resistance determinants in these purified bacterial strains are present on respective plasmids. Altogether, the data suggested that the human workplaces are the hotspot for the prevalence of MDR bacteria and thus may serve as the source of horizontal gene transfer and further transmission to other environments.


Assuntos
Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Farmacorresistência Bacteriana Múltipla , Toaletes , Local de Trabalho , Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética , Microbiologia Ambiental , Feminino , Humanos , Higiene , Masculino , Exposição Ocupacional , Paquistão , Filogenia , Plasmídeos , Prevalência , Fatores R , RNA Ribossômico 16S/genética , Saneamento
7.
Proc Natl Acad Sci U S A ; 117(33): 20202-20210, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747578

RESUMO

In biology, it is often critical to determine the identity of an organism and phenotypic traits of interest. Whole-genome sequencing can be useful for this but has limited power for trait prediction. However, we can take advantage of the inherent information content of phenotypes to bypass these limitations. We demonstrate, in clinical and environmental bacterial isolates, that growth dynamics in standardized conditions can differentiate between genotypes, even among strains from the same species. We find that for pairs of isolates, there is little correlation between genetic distance, according to phylogenetic analysis, and phenotypic distance, as determined by growth dynamics. This absence of correlation underscores the challenge in using genomics to infer phenotypes and vice versa. Bypassing this complexity, we show that growth dynamics alone can robustly predict antibiotic responses. These findings are a foundation for a method to identify traits not easily traced to a genetic mechanism.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/genética , Antibacterianos/farmacologia , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla , Enterobacteriaceae/efeitos dos fármacos , Microbiologia Ambiental , Regulação Bacteriana da Expressão Gênica , Polimorfismo de Nucleotídeo Único , Especificidade da Espécie , Fatores de Tempo
8.
Math Biosci ; 328: 108441, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32763338

RESUMO

Since its emergence late in 2019, the COVID-19 pandemic continues to exude major public health and socio-economic burden globally. South Africa is currently the epicenter for the pandemic in Africa. This study is based on the use of a compartmental model to analyze the transmission dynamics of the disease in South Africa. A notable feature of the model is the incorporation of the role of environmental contamination by COVID-infected individuals. The model, which is fitted and parametrized using cumulative mortality data from South Africa, is used to assess the impact of various control and mitigation strategies. Rigorous analysis of the model reveals that its associated continuum of disease-free equilibria is globally-asymptotically stable whenever the control reproduction number is less than unity. The epidemiological implication of this result is that the disease will eventually die out, particularly if control measures are implemented early and for a sustainable period of time. For instance, numerical simulations suggest that if the lockdown measures in South Africa were implemented a week later than the 26 March, 2020 date it was implemented, this will result in the extension of the predicted peak time of the pandemic, and causing about 10% more cumulative deaths. In addition to illustrating the effectiveness of self-isolation in reducing the number of cases, our study emphasizes the importance of surveillance testing and contact tracing of the contacts and confirmed cases in curtailing the pandemic in South Africa.


Assuntos
Betacoronavirus , Infecções por Coronavirus/transmissão , Modelos Biológicos , Pandemias , Pneumonia Viral/transmissão , Número Básico de Reprodução , Técnicas de Laboratório Clínico , Simulação por Computador , Busca de Comunicante , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Microbiologia Ambiental , Monitoramento Epidemiológico , Humanos , Conceitos Matemáticos , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Quarentena , África do Sul/epidemiologia , Fatores de Tempo
10.
Acta Biomed ; 91(9-S): 76-78, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32701919

RESUMO

The COVID-19 pandemic, affecting 213 countries, with more than 10 million cases and over 500,000 deaths is still causing serious health, social and economic emergency worldwide. Italian Northern regions are among the most badly affected areas. Surfaces represent matrices to which particular attention should be paid for prevention and control of SARS-CoV-2 transmission. A few studies have highlighted virus presence on surfaces. We report the evidence of its presence on hospital surfaces, in a single room hosting a patient whose nose-pharyngeal swab resulted positive for SARS-CoV-2 RNA at the admission. The surfaces sampling was carried out using pre-wetted swabs followed by extraction and amplification of viral RNA by reverse Real-Time Polymerase Chain Reaction (rRT-PCR). A total of 4/15 (26.66%) surfaces were positive for SARS-CoV-2 RNA: the right bed rail, the call button, the bed trapeze bar, the stethoscope; moreover, the patient's inner surgical mask was positive, showing the emission of the virus from the patient. This study is a further confirmation that the surfaces represent a potential vehicle of transmission. This supports the need for strict adherence to hand and environmental hygiene.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Pneumonia Viral/transmissão , Infecções por Coronavirus/virologia , Microbiologia Ambiental , Hospitais , Humanos , Pandemias , Pneumonia Viral/virologia , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real
11.
Epidemiol Infect ; 148: e154, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32660668

RESUMO

There is limited information concerning the viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in aerosols deposited on environmental surfaces and the effectiveness of infection prevention and control procedures on eliminating SARS-CoV-2 contamination in hospital settings. We examined the concentration of SARS-CoV-2 in aerosol samples and on environmental surfaces in a hospital designated for treating severe COVID-19 patients. Aerosol samples were collected by a microbial air sampler, and environmental surfaces were sampled using sterile premoistened swabs at multiple sites. Ninety surface swabs and 135 aerosol samples were collected. Only two swabs, sampled from the inside of a patient's mask, were positive for SARS-CoV-2 RNA. All other swabs and aerosol samples were negative for the virus. Our study indicated that strict implementation of infection prevention and control procedures was highly effective in eliminating aerosol and environmental borne SARS-CoV-2 RNA thereby reducing the risk of cross-infection in hospitals.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Infecção Hospitalar/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , RNA Viral/isolamento & purificação , Carga Viral , Aerossóis , Betacoronavirus/genética , Infecções por Coronavirus/transmissão , Infecção Hospitalar/transmissão , Infecção Hospitalar/virologia , Meio Ambiente , Microbiologia Ambiental , Hospitais Universitários , Humanos , Máscaras/virologia , Pneumonia Viral/transmissão
12.
Mikrobiyol Bul ; 54(2): 291-305, 2020 Apr.
Artigo em Turco | MEDLINE | ID: mdl-32723284

RESUMO

Aspergillus fumigatus can cause different clinical manifestations including chronic pulmonary infections, as well as invasive aspergillosis which is highly mortal in the immunocompromised host. Azole antifungal drugs, voriconazole in particular, are the first-line recommended therapeutic regimen. Azoles inhibit 14-α demethylase enzyme encoded by the cyp51A gene. In recent years, increased azole resistance is observed among environmental and clinical A.fumigatus isolates. Two different mechanisms have been proposed for the development of resistance. The first one is the triggering of resistance as a result of long-term clinical azole use. Point mutations in cyp51A gene are generally responsible for this type of azole resistance. The second mechanism is incidental environmental azole exposure due to the use of azoles as agricultural fungicides. Contact with azoles for extended periods and at varying concentrations causes selective pressure and mutations on sporulating A.fumigatus. Since the resistant strains may persist in nature, susceptible individuals may be infected by acquisition of these strains from the environment. When genotypically examined, the cyp51A gene of the resistant isolates of environmental origin specifically presents with a tandem repeat in the promoter region in addition to the point mutation in codon 98 (TR34/L98H). The aim of this study was to investigate azole resistance rates in A.fumigatus strains isolated from clinical specimens and landscaping areas around Hacettepe University Faculty of Medicine Hospital by phenotypical and genotypical methods. Agar screening test was used as the initial test to detect azole resistance in isolates identified as A.fumigatus sensu stricto according to thermotolerance test results. For all strains that grew on any of the azole containing plates in agar screening test, minimum inhibitory concentration (MIC) values were determined by "European Committee on Antimicrobial Susceptibilitiy Testing" reference microdilution method for the confirmation of the resistance. In addition, cyp51A gene sequence was investigated in selected isolates and mutation analysis was performed. A total of 483 clinical and 65 environmental A.fumigatus sensu stricto isolates were included in the study. The first group of clinical isolates consisted of 215 strains isolated in 1997-2015, revived from stock and tested. The second group consisted of 268 strains belonging to the time period of 2016-2018, during which routine azole agar screening tests were performed for A.fumigatus isolates. When all isolates (n= 483) were evaluated together, 11 isolates (1 before 2015 and 10 between 2016-2018), were found to be resistant to itraconazole (2.3%). None of the mutations previously reported to be associated with azole resistance in Aspergillus strains that were detected in cyp51A sequence analysis, However, polymorphisms which are not (yet) fully elucidated in relation to the resistance (Y46F, G89G, V172M, T248N, E255D, L358L, K427E, C454C, Y431D and Q141H in one strain) were shown to exist in resistant isolates. These results have shown that the rate of azole resistance among clinical A.fumigatus isolates was low (2.3%) in our center. Further studies are required to demonstrate the possible role of the detected polymorphisms on azole resistance and to clarify other mechanisms related with high azole MIC values. In addition, since high azole resistance has been reported from one region in our country, it has been concluded that multicenter studies are required to determine the azole resistance status and the range for the azole resistance ratio in different regions and to reveal resistance mutations that may be specific to our country.


Assuntos
Antifúngicos , Aspergilose , Aspergillus fumigatus , Farmacorresistência Fúngica , Antifúngicos/farmacologia , Aspergilose/microbiologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Farmacorresistência Fúngica/genética , Microbiologia Ambiental , Humanos , Testes de Sensibilidade Microbiana
14.
PLoS One ; 15(6): e0234364, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530933

RESUMO

Inadequate sanitation can lead to exposure to fecal contamination through multiple environmental pathways and can result in adverse health outcomes. By understanding the relative importance of multiple exposure pathways, sanitation interventions can be tailored to those pathways with greatest potential public health impact. The SaniPath Exposure Assessment Tool allows users to identify and quantify human exposure to fecal contamination in low-resource urban settings through a systematic yet customizable process. The Tool includes: a project management platform; mobile data collection and a data repository; protocols for primary data collection; and automated exposure assessment analysis. The data collection protocols detail the process of conducting behavioral surveys with households, school children, and community groups to quantify contact with fecal exposure pathways and of collecting and analyzing environmental samples for E. coli as an indicator of fecal contamination. Bayesian analyses are used to estimate the percentage of the population exposed and the mean dose of fecal exposure from microbiological and behavioral data. Fecal exposure from nine pathways (drinking water, bathing water, surface water, ocean water, open drains, floodwater, raw produce, street food, and public or shared toilets) can be compared through a common metric-estimated ingestion of E. coli units (MPN or CFU) per month. The Tool generates data visualizations and recommendations for interventions designed for both scientific and lay audiences. When piloted in Accra, Ghana, the results of the Tool were comparable with that of an in-depth study conducted in the same neighborhoods and highlighted consumption of raw produce as a dominant exposure pathway. The Tool has been deployed in nine cities to date, and the results are being used by local authorities to design and prioritize programming and policy. The SaniPath Tool is a novel approach to support public-health evidence-based decision-making for urban sanitation policies and investments.


Assuntos
Microbiologia Ambiental , Monitoramento Ambiental/métodos , Fezes/microbiologia , Saneamento/estatística & dados numéricos , Software , Cidades , Tomada de Decisões , Exposição Ambiental , Monitoramento Ambiental/estatística & dados numéricos , Escherichia coli/isolamento & purificação , Contaminação de Alimentos , Gana , Humanos , Projetos Piloto , Formulação de Políticas , Pobreza , Saúde Pública , Saúde da População Urbana , Microbiologia da Água
15.
ACS Nano ; 14(6): 6383-6406, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32519842

RESUMO

The COVID-19 outbreak has fueled a global demand for effective diagnosis and treatment as well as mitigation of the spread of infection, all through large-scale approaches such as specific alternative antiviral methods and classical disinfection protocols. Based on an abundance of engineered materials identifiable by their useful physicochemical properties through versatile chemical functionalization, nanotechnology offers a number of approaches to cope with this emergency. Here, through a multidisciplinary Perspective encompassing diverse fields such as virology, biology, medicine, engineering, chemistry, materials science, and computational science, we outline how nanotechnology-based strategies can support the fight against COVID-19, as well as infectious diseases in general, including future pandemics. Considering what we know so far about the life cycle of the virus, we envision key steps where nanotechnology could counter the disease. First, nanoparticles (NPs) can offer alternative methods to classical disinfection protocols used in healthcare settings, thanks to their intrinsic antipathogenic properties and/or their ability to inactivate viruses, bacteria, fungi, or yeasts either photothermally or via photocatalysis-induced reactive oxygen species (ROS) generation. Nanotechnology tools to inactivate SARS-CoV-2 in patients could also be explored. In this case, nanomaterials could be used to deliver drugs to the pulmonary system to inhibit interaction between angiotensin-converting enzyme 2 (ACE2) receptors and viral S protein. Moreover, the concept of "nanoimmunity by design" can help us to design materials for immune modulation, either stimulating or suppressing the immune response, which would find applications in the context of vaccine development for SARS-CoV-2 or in counteracting the cytokine storm, respectively. In addition to disease prevention and therapeutic potential, nanotechnology has important roles in diagnostics, with potential to support the development of simple, fast, and cost-effective nanotechnology-based assays to monitor the presence of SARS-CoV-2 and related biomarkers. In summary, nanotechnology is critical in counteracting COVID-19 and will be vital when preparing for future pandemics.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Nanotecnologia/métodos , Pandemias , Pneumonia Viral , Betacoronavirus/genética , Betacoronavirus/imunologia , Biomimética , Simulação por Computador , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Citocinas/antagonistas & inibidores , Citocinas/biossíntese , Desinfecção , Sistemas de Liberação de Medicamentos , Microbiologia Ambiental , Humanos , Imunomodulação , Máscaras , Nanomedicina , Nanotecnologia/tendências , Pandemias/prevenção & controle , Equipamento de Proteção Individual , Fotoquimioterapia , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Vacinas Virais/genética , Vacinas Virais/farmacologia
16.
Science ; 368(6495): 1135-1140, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32499444

RESUMO

Determining where an object has been is a fundamental challenge for human health, commerce, and food safety. Location-specific microbes in principle offer a cheap and sensitive way to determine object provenance. We created a synthetic, scalable microbial spore system that identifies object provenance in under 1 hour at meter-scale resolution and near single-spore sensitivity and can be safely introduced into and recovered from the environment. This system solves the key challenges in object provenance: persistence in the environment, scalability, rapid and facile decoding, and biocontainment. Our system is compatible with SHERLOCK, a Cas13a RNA-guided nucleic acid detection assay, facilitating its implementation in a wide range of applications.


Assuntos
Código de Barras de DNA Taxonômico/métodos , DNA Bacteriano/isolamento & purificação , DNA Fúngico/isolamento & purificação , Microbiologia Ambiental , Microbiota/genética , Esporos/genética , Sistemas CRISPR-Cas , DNA Bacteriano/genética , DNA Fúngico/genética , RNA Guia
17.
mSphere ; 5(3)2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32581071

RESUMO

The contamination of patients' surroundings by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains understudied. We sampled the surroundings and the air of six negative-pressure non-intensive care unit (non-ICU) rooms in a designated isolation ward in Chengdu, China, that were occupied by 13 laboratory-confirmed coronavirus disease 2019 (COVID-19) patients who had returned from overseas travel, including 2 asymptomatic patients. A total of 44 of 112 (39.3%) surface samples were positive for SARS-CoV-2 as detected by real-time PCR, suggesting extensive contamination, although all of the air samples were negative. In particular, in a single room occupied by an asymptomatic patient, four sites were SARS-CoV-2 positive, highlighting that asymptomatic COVID-19 patients do contaminate their surroundings and impose risks for others with close contact. Placement of COVID-19 patients in rooms with negative pressure may bring a false feeling of safety, and the importance of rigorous environment cleaning should be emphasized.IMPORTANCE Although it has been well recognized that the virus SARS-CoV-2, the causative agent of COVID-19, can be acquired by exposure to fomites, surprisingly, the contamination of patients' surroundings by SARS-CoV-2 is largely unknown, as there have been few studies. We performed an environmental sampling study for 13 laboratory-confirmed COVID-19 patients and found extensive contamination of patients' surroundings. In particular, we found that asymptomatic COVID-19 patients contaminated their surroundings and therefore imposed risks for other people. Environment cleaning should be emphasized in negative-pressure rooms. The findings may be useful to guide infection control practice to protect health care workers.


Assuntos
Infecções Assintomáticas/epidemiologia , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Exposição Ambiental , Microbiologia Ambiental , Pneumonia Viral/epidemiologia , Contenção de Riscos Biológicos/métodos , Infecções por Coronavirus/patologia , Meio Ambiente , Humanos , Pandemias , Pneumonia Viral/patologia
18.
Photochem Photobiol ; 96(4): 731-737, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32502327

RESUMO

Using a model developed for estimating solar inactivation of viruses of biodefense concerns, we calculated the expected inactivation of SARS-CoV-2 virus, cause of COVID-19 pandemic, by artificial UVC and by solar ultraviolet radiation in several cities of the world during different times of the year. The UV sensitivity estimated here for SARS-CoV-2 is compared with those reported for other ssRNA viruses, including influenza A virus. The results indicate that SARS-CoV-2 aerosolized from infected patients and deposited on surfaces could remain infectious outdoors for considerable time during the winter in many temperate-zone cities, with continued risk for re-aerosolization and human infection. Conversely, the presented data indicate that SARS-CoV-2 should be inactivated relatively fast (faster than influenza A) during summer in many populous cities of the world, indicating that sunlight should have a role in the occurrence, spread rate and duration of coronavirus pandemics.


Assuntos
Betacoronavirus/efeitos da radiação , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Energia Solar , Luz Solar , Inativação de Vírus/efeitos da radiação , Aerossóis/efeitos da radiação , Microbiologia do Ar , Infecções por Coronavirus/virologia , Microbiologia Ambiental , Humanos , Modelos Biológicos , Pneumonia Viral/virologia , Tolerância a Radiação , Estações do Ano , Raios Ultravioleta , Tempo (Meteorologia)
19.
Arch Microbiol ; 202(8): 2329-2336, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32529508

RESUMO

Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) is a rapid, cost-effective and high-throughput method for bacteria characterization. However, most previous studies focused on clinical isolates. In this study, we evaluated the use of MALDI-TOF MS as a rapid screening tool for marine bacterial symbionts. A set of 255 isolates from different marine sources (corals, sponge, fish and seawater) was analyzed using cell lysates to obtain a rapid grouping. Cluster analysis of mass spectra and 16S rRNA showed 18 groups, including Vibrio, Bacillus, Pseudovibrio, Alteromonas and Ruegeria. MALDI-TOF distance similarity scores ≥ 60% and ≥ 70% correspond to ≥ 98.7% 16S rRNA gene sequence similarity and ≥ 95% pyrH gene sequence similarity, respectively. MALDI-TOF MS is a useful tool for Vibrio species groups' identification.


Assuntos
Microbiologia Ambiental , Biologia Marinha/métodos , Água do Mar/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Vibrio/classificação , RNA Ribossômico 16S/genética , Simbiose , Vibrio/química , Vibrio/genética
20.
Appl Environ Microbiol ; 86(17)2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32591388

RESUMO

The infection of health care workers during the 2013 to 2016 Ebola outbreak raised concerns about fomite transmission. In the wake of the coronavirus disease 2019 (COVID-19) pandemic, investigations are ongoing to determine the role of fomites in coronavirus transmission as well. The bacteriophage phi 6 has a phospholipid envelope and is commonly used in environmental studies as a surrogate for human enveloped viruses. The persistence of phi 6 was evaluated as a surrogate for Ebola virus (EBOV) and coronaviruses on porous and nonporous hospital surfaces. Phi 6 was suspended in a body fluid simulant and inoculated onto 1-cm2 coupons of steel, plastic, and two fabric curtain types. The coupons were placed at two controlled absolute humidity (AH) levels: a low AH of 3.0 g/m3 and a high AH of 14.4 g/m3 Phi 6 declined at a lower rate on all materials under low-AH conditions, with a decay rate of 0.06-log10 PFU/day to 0.11-log10 PFU/day, than under the higher AH conditions, with a decay rate of 0.65-log10 PFU/h to 1.42-log10 PFU/day. There was a significant difference in decay rates between porous and nonporous surfaces at both low AH (P < 0.0001) and high AH (P < 0.0001). Under these laboratory-simulated conditions, phi 6 was found to be a conservative surrogate for EBOV under low-AH conditions in that it persisted longer than Ebola virus in similar AH conditions. Additionally, some coronaviruses persist longer than phi 6 under similar conditions; therefore, phi 6 may not be a suitable surrogate for coronaviruses.IMPORTANCE Understanding the persistence of enveloped viruses helps inform infection control practices and procedures in health care facilities and community settings. These data convey to public health investigators that enveloped viruses can persist and remain infective on surfaces, thus demonstrating a potential risk for transmission. Under these laboratory-simulated Western indoor hospital conditions, we assessed the suitability of phi 6 as a surrogate for environmental persistence research related to enveloped viruses, including EBOV and coronaviruses.


Assuntos
Bacteriófago phi 6/isolamento & purificação , Bacteriófago phi 6/fisiologia , Coronavirus/fisiologia , Ebolavirus/fisiologia , Microbiologia Ambiental , Fômites/virologia , Inativação de Vírus , Betacoronavirus/fisiologia , Coronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Hospitais , Humanos , Umidade , Pandemias , Pneumonia Viral/transmissão , Porosidade , Temperatura
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