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1.
mSphere ; 5(4)2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611701

RESUMO

Coronavirus disease 2019 (COVID-19) was first identified in China in late 2019 and is caused by newly identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Previous studies had reported the stability of SARS-CoV-2 in cell culture media and deposited onto surfaces under a limited set of environmental conditions. Here, we broadly investigated the effects of relative humidity, temperature, and droplet size on the stability of SARS-CoV-2 in a simulated clinically relevant matrix dried on nonporous surfaces. The results show that SARS-CoV-2 decayed more rapidly when either humidity or temperature was increased but that droplet volume (1 to 50 µl) and surface type (stainless steel, plastic, or nitrile glove) did not significantly impact decay rate. At room temperature (24°C), virus half-life ranged from 6.3 to 18.6 h depending on the relative humidity but was reduced to 1.0 to 8.9 h when the temperature was increased to 35°C. These findings suggest that a potential for fomite transmission may persist for hours to days in indoor environments and have implications for assessment of the risk posed by surface contamination in indoor environments.IMPORTANCE Mitigating the transmission of SARS-CoV-2 in clinical settings and public spaces is critically important to reduce the number of COVID-19 cases while effective vaccines and therapeutics are under development. SARS-CoV-2 transmission is thought to primarily occur through direct person-to-person transfer of infectious respiratory droplets or through aerosol-generating medical procedures. However, contact with contaminated surfaces may also play a significant role. In this context, understanding the factors contributing to SARS-CoV-2 persistence on surfaces will enable a more accurate estimation of the risk of contact transmission and inform mitigation strategies. To this end, we have developed a simple mathematical model that can be used to estimate virus decay on nonporous surfaces under a range of conditions and which may be utilized operationally to identify indoor environments in which the virus is most persistent.


Assuntos
Fômites/virologia , Umidade , Modelos Teóricos , Vírus da SARS/fisiologia , Temperatura , Inativação de Vírus , Poluição do Ar em Ambientes Fechados , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Meia-Vida , Humanos , Pandemias/prevenção & controle , Plásticos , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Porosidade , Saliva/química , Saliva/virologia , Aço Inoxidável , Propriedades de Superfície
3.
BMC Infect Dis ; 20(1): 411, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532220

RESUMO

BACKGROUND: The prevalence of healthcare-acquired infections (HAI) and rising levels of antimicrobial resistance places significant economic and public health burdens on modern healthcare systems. A group of highly drug resistant pathogens known as the ESKAPE pathogens, along with C. difficile, are the leading causes of HAIs. Interactions between patients, healthcare workers, and environmental conditions impact disease transmission. Studying pathogen transfer under varying contact scenarios in a controlled manner is critical for understanding transmission and disinfectant strategies. In lieu of human subject research, this method has the potential to contribute to modeling the routes of pathogen transmission in healthcare settings. METHODS: To overcome these challenges, we have developed a method that utilizes a synthetic skin surrogate to model both direct (skin-to-skin) and indirect (skin-to fomite-to skin) pathogen transfer between infected patients and healthy healthcare workers. This surrogate material includes a background microbiome community simulating typical human skin flora to more accurately mimic the effects of natural flora during transmission events. RESULTS: We demonstrate the ability to modulate individual bacterial concentrations within this microbial community to mimic bacterial concentrations previously reported on the hands of human subjects. We also explore the effect of various decontamination approaches on pathogen transfer between human subjects, such as the use of handwashing or surface disinfectants. Using this method, we identify a potential outlier, S. aureus, that may persist and retain viability in specific transfer conditions better than the overall microbial community during decontamination events. CONCLUSIONS: Our work describes the development of an in vitro method that uses a synthetic skin surrogate with a defined background microbiota to simulate skin-to-skin and skin-to fomite-to skin contact scenarios. These results illustrate the value of simulating a holistic microbial community for transfer studies by elucidating differences in different pathogen transmission rates and resistance to common decontamination practices. We believe this method will contribute to improvements in pathogen transmission modeling in healthcare settings and increase our ability to assess the risk associated with HAIs, although additional research is required to establish the degree of correlation of pathogen transmission by skin or synthetic alternatives.


Assuntos
Infecção Hospitalar/microbiologia , Infecção Hospitalar/transmissão , Modelos Biológicos , Clostridium difficile , Infecção Hospitalar/prevenção & controle , Descontaminação/métodos , Resistência Microbiana a Medicamentos , Fômites/microbiologia , Humanos , Viabilidade Microbiana , Microbiota , Pele/microbiologia , Especificidade da Espécie
4.
Med Hypotheses ; 141: 109781, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32361528

RESUMO

The world is facing a pandemic of unseen proportions caused by a corona virus named SARS-CoV-2 with unprecedent worldwide measures being taken to tackle its contagion. Person-to-person transmission is accepted but WHO only considers aerosol transmission when procedures or support treatments that produce aerosol are performed. Transmission mechanisms are not fully understood and there is evidence for an airborne route to be considered, as the virus remains viable in aerosols for at least 3 h and that mask usage was the best intervention to prevent infection. Heating, Ventilation and Air Conditioning Systems (HVAC) are used as a primary infection disease control measure. However, if not correctly used, they may contribute to the transmission/spreading of airborne diseases as proposed in the past for SARS. The authors believe that airborne transmission is possible and that HVAC systems when not adequately used may contribute to the transmission of the virus, as suggested by descriptions from Japan, Germany, and the Diamond Princess Cruise Ship. Previous SARS outbreaks reported at Amoy Gardens, Emergency Rooms and Hotels, also suggested an airborne transmission. Further studies are warranted to confirm our hypotheses but the assumption of such way of transmission would cause a major shift in measures recommended to prevent infection such as the disseminated use of masks and structural changes to hospital and other facilities with HVAC systems.


Assuntos
Microbiologia do Ar , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Ambiente Controlado , Pandemias , Pneumonia Viral/transmissão , Ventilação , Aerossóis , Ar Condicionado/efeitos adversos , Ar Condicionado/instrumentação , Ar Condicionado/métodos , Poluição do Ar em Ambientes Fechados , Infecções por Coronavirus/prevenção & controle , Infecção Hospitalar/transmissão , Contaminação de Equipamentos , Desenho de Equipamento , Falha de Equipamento , Fômites/virologia , Calefação/efeitos adversos , Calefação/instrumentação , Calefação/métodos , Humanos , Doença dos Legionários/epidemiologia , Doença dos Legionários/transmissão , Modelos Biológicos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Engenharia Sanitária/instrumentação , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/transmissão , Esgotos/virologia , Ventilação/instrumentação , Ventilação/métodos
5.
Proc Natl Acad Sci U S A ; 117(22): 11875-11877, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32404416

RESUMO

Speech droplets generated by asymptomatic carriers of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are increasingly considered to be a likely mode of disease transmission. Highly sensitive laser light scattering observations have revealed that loud speech can emit thousands of oral fluid droplets per second. In a closed, stagnant air environment, they disappear from the window of view with time constants in the range of 8 to 14 min, which corresponds to droplet nuclei of ca. 4 µm diameter, or 12- to 21-µm droplets prior to dehydration. These observations confirm that there is a substantial probability that normal speaking causes airborne virus transmission in confined environments.


Assuntos
Microbiologia do Ar , Betacoronavirus/fisiologia , Infecções por Coronavirus/transmissão , Pneumonia Viral/transmissão , Saliva/virologia , Difusão Dinâmica da Luz , Fômites/virologia , Humanos , Pandemias , Tamanho da Partícula , Vírus da SARS , Saliva/química , Fala , Carga Viral
6.
PLoS Negl Trop Dis ; 14(3): e0008120, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32130213

RESUMO

BACKGROUND: Trachoma elimination efforts are hampered by limited understanding of Chlamydia trachomatis (Ct) transmission routes. Here we aimed to detect Ct DNA at non-ocular sites and on eye-seeking flies. METHODS: A population-based household survey was conducted in Oromia Region, Ethiopia. Ocular and non-ocular (faces, hands, clothing, water containers and sleeping surfaces) swabs were collected from all individuals. Flies were caught from faces of children. Flies, ocular swabs and non-ocular swabs were tested for Ct by quantitative PCR. RESULTS: In total, 1220 individuals in 247 households were assessed. Active trachoma (trachomatous inflammation-follicular) and ocular Ct were detected in 10% and 2% of all-ages, and 21% and 3% of 1-9-year-olds, respectively. Ct was detected in 12% (95% CI:8-15%) of tested non-ocular swabs from ocular-positive households, but in none of the non-ocular swabs from ocular-negative households. Ct was detected on 24% (95% CI:18-32%) of flies from ocular-positive households and 3% (95% CI:1-6%) of flies from ocular-negative households. CONCLUSION: Ct DNA was detected on hands, faces and clothing of individuals living in ocular-positive households suggesting that this might be a route of transmission within Ct infected households. In addition, we detected Ct on flies from ocular-positive households and occasionally in ocular-negative households suggesting that flies might be a vector for transmission within and between Ct infected and uninfected households. These potential transmission routes may need to be simultaneously addressed to suppress transmission.


Assuntos
Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/transmissão , Chlamydia trachomatis/isolamento & purificação , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/transmissão , Transmissão de Doença Infecciosa , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Chlamydia trachomatis/genética , Vestuário , Estudos Transversais , Dípteros/microbiologia , Etiópia , Fezes/microbiologia , Feminino , Fômites/microbiologia , Mãos/microbiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
7.
J Appl Microbiol ; 128(4): 1050-1059, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31782200

RESUMO

AIMS: The purpose of this study was to evaluate the effects of altered environmental conditions on the persistence of Francisella tularensis bacteria and Venezuelan equine encephalitis virus (VEEV), on two material types. METHODS AND RESULTS: Francisella tularensis (F.t.) and VEEV were inoculated (c. 1 × 108 colony-forming units or PFU), dried onto porous and nonporous fomites (glass and paper), and exposed to combinations of altered environmental conditions ranging from 22 to 60°C and 30 to 75% relative humidity (RH). Viability of test organism was assessed after contact times ranging from 30 min to 10 days. Inactivation rates of F.t. and VEEV increased as both temperature and/or RH were increased. Greater efficacy was observed for paper as compared to glass for both test organisms. CONCLUSIONS: The use of elevated temperature and RH increased rate of inactivation for both organisms and greater than six log reduction was accomplished in as little as 6 h by elevating temperature to approximately 60°C. SIGNIFICANCE AND IMPACT OF THE STUDY: These results provide information for inactivation of nonspore-forming select agents using elevated temperature and humidity which may aid incident commanders following a biological contamination incident by providing alternative methods for remediation.


Assuntos
Descontaminação/métodos , Vírus da Encefalite Equina Venezuelana/crescimento & desenvolvimento , Fômites/microbiologia , Francisella tularensis/crescimento & desenvolvimento , Fômites/classificação , Vidro/química , Umidade , Viabilidade Microbiana , Papel , Temperatura , Inativação de Vírus
8.
Indoor Air ; 30(1): 49-59, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31545534

RESUMO

Touching contaminated surfaces might lead to the spread of pathogens, that is, the fomite transmission route. Although hand- and surface-hygiene practices are potentially important non-pharmaceutical interventions for the fomite route, the two interventions have been mostly studied separately in the literature. In this study, we develop a new conceptual model based on the law of mass action, analyze the temporal diffusion of contaminated surfaces and hands, and verify the model with simulations in an assumed norovirus outbreak in a buffet restaurant. A quantitative hygiene criterion is developed for the required frequency of surface disinfection and hand hygiene to control the fomite transmission in indoor environments. To eliminate surface contaminations, the product of pathogen-removal rates (including hygiene and natural death) on hands and surfaces must be no smaller than that of the human hand and surface contact frequency (ie, the net removal product must be non-negative). When the net removal product is negative, the number of contaminated surfaces and hands would show a logistic growth trend and finally approach the equilibrium. Our approach sheds light into how to optimize the combined use of hand hygiene and environmental decontamination for the best effectiveness under different settings.


Assuntos
Desinfecção , Fômites , Higiene das Mãos , Descontaminação , Mãos , Desinfecção das Mãos , Humanos
9.
Infez Med ; 27(4): 374-379, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31846986

RESUMO

Cell phones are one of the most important and indispensable accessories for professional and social life. Cell phones used by healthcare workers are highly contaminated by microorganisms. The objective of the study was to ascertain the presence of bacterial resistance type Extended-Spectrum Beta-Lactamase [ESBL] and its related factors in cultures isolated from cell phones of medical students. A quantitative, observational, analytical and transversal study was carried out in students of the Faculty of Medicine of the Universidad Nacional Hermilio Valdizán in Huánuco, Peru. The relationship was sought between the frequency of attendance at hospital practices, cell phone disinfection and hand washing after contact with patients with the presence of ESBL-type bacterial resistance. Of the total sample, 95% of students presented positive culture to Gram-negative bacteria, 30% carried out the disinfection of their cell phone and only 5% of the students performed hand-washing in an appropriate manner. In the bivariate analysis, a statistical association was found between cell phone disinfection and the presence of ESBL-type bacterial resistance [p <0.05]. Cell phone disinfection is related to the reduction of ESBL-type resistance, highlighting the need for disinfection of cell phones after performing hospital practices.


Assuntos
Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Telefone Celular , Desinfecção/normas , Farmacorresistência Bacteriana , Fômites/microbiologia , Estudantes de Medicina , Adulto , Bactérias/enzimologia , Estudos de Avaliação como Assunto , Feminino , Desinfecção das Mãos/normas , Humanos , Masculino , Peru , Adulto Jovem , beta-Lactamases/metabolismo
10.
Pol J Vet Sci ; 22(4): 777-780, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31867917

RESUMO

Four commercial disinfectants were chosen for being generally accepted as effective against ASFV. Only two of them, based on sodium hypochlorite and potassium peroxymonosulfate, confirmed their effectiveness in selected concentrations. Taken together, our data supports the effectivenes of chemical disinfectants containing sodium hypochlorite (1%, 0.5% in low level soiling) and potassium peroxymonosulfate (1% in high level soiling). Furthermore, these results highlight the importance of pre-cleaning steps to remove soiling before proper disinfection which improves the effectiveness of tested disinfectants.


Assuntos
Vírus da Febre Suína Africana/efeitos dos fármacos , Desinfetantes/farmacologia , Fômites
11.
PLoS One ; 14(12): e0226952, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31881059

RESUMO

We monitored the survival of human pathogenic bacteria [Escherichia coli (ATCC), extended-spectrum ß-lactamase-producing E. coli (Clinical isolate), New Delhi metallo-ß-lactamase-producing E. coli (clinical isolate), Staphylococcus aureus (ATCC)] on dry materials (vinyl chloride, aluminum, plastic, stainless steel) at distinct temperatures (room temperature or 15°C-37°C). These bacteria favored a lower temperature for their prolonged survival on the dry fomites, regardless of the material type. Interestingly, when mixed with S. aureus, E. coli survived for a longer time at a lower temperature. Cardiolipin, which can promote the survival of S. aureus in harsh environments, had no effect on maintaining the survival of E. coli. Although the trends remained unchanged, adjusting the humidity from 40% to 60% affected the survival of bacteria on dry surfaces. Scanning electron microscopic analysis revealed no morphological differences in these bacteria immediately before or after one day of dry conditions. In addition, ATP assessment, a method used to visualize high-touch surfaces in hospitals, was not effective at monitoring bacterial dynamics. A specialized handrail device fitted with a heater, which was maintained at normal human body core temperature, successfully prohibited the prolonged survival of bacteria [Enterococcus faecalis (ATCC), E. coli (ATCC), Pseudomonas aeruginosa (ATCC), S. aureus (ATCC), Acinetobacter baumannii (clinical isolate), and Serratia marcescens (clinical isolate)], with the exception of spore-forming Bacillus subtilis (from our laboratory collection) and the yeast-like fungus Candida albicans (from our laboratory collection)] on dry surfaces. Taken together, we concluded that the tested bacteria favor lower temperatures for their survival in dry environments. Therefore, the thermal control of dry fomites has the potential to control bacterial survival on high-touch surfaces in hospitals.


Assuntos
Infecções Bacterianas/microbiologia , Infecção Hospitalar/microbiologia , Fômites/microbiologia , Acinetobacter baumannii/fisiologia , Bacillus subtilis/fisiologia , Enterococcus faecalis/fisiologia , Escherichia coli/fisiologia , Temperatura Alta , Humanos , Viabilidade Microbiana , Pseudomonas aeruginosa/fisiologia , Serratia marcescens/fisiologia , Staphylococcus aureus/fisiologia , Temperatura
12.
BMC Res Notes ; 12(1): 621, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547851

RESUMO

OBJECTIVE: To determine bacterial contaminants and their antimicrobial susceptibility patterns from medical equipment and inanimate surfaces. RESULTS: Of 130 swabs, 115 (88.5%) swabs were culture positive, of which contaminated medical equipment and inanimate surfaces account 70 (83.3%) and 45 (97.8%), respectively. All the swabs collected from sphygmomanometer, bedside table, computer and computer standing tables were 100% contaminated with bacteria. From the culture-positive swabs, a total of 171 bacterial isolates were identified, out of which 117 (68.4%) and 54 (31.6%) isolates were gram-positive and gram-negative, respectively. Most isolates (82%) were resistant to ampicillin and 13%, 8.6%, and 14% was observed in ciprofloxacin, gentamicin, and tetracycline respectively. Multi-drug resistant was observed in Escherichia coli (72.7%) and Staphylococcus aureus (58.7%).


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Contaminação de Equipamentos/estatística & dados numéricos , Fômites/microbiologia , Ciprofloxacino/farmacologia , Estudos Transversais , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Etiópia , Gentamicinas/farmacologia , Hospitais Especializados , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Tetraciclina/farmacologia
13.
Environ Int ; 132: 105119, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31491607

RESUMO

Bike-sharing as a common public transportation has been booming in China in recent years. Previous studies showed that the surfaces of public transport can act as reservoirs of antimicrobial-resistant (AR) bacteria, but AR bacterial contamination of shared bikes has not been investigated. Otherwise, the AR-Enterobacteriaceae is considered as a global health threat for humans. Herein, we aimed to investigate the prevalence of AR Enterobacteriaceae on shared bikes and examine correlations between AR Enterobacteriaceae from shared bikes and public buildings around Metro stations in Beijing. We collected 2117 samples from shared bikes at 240 Metro stations in Beijing. A total of 444 non-duplicate Enterobacteriaceae were isolated from 418 samples at 166 stations. The isolates exhibited low rates of resistance (0.5%-6.3%) to all antimicrobial agents except sulfamethoxazole-trimethoprim (31.5%). Three ceftazidime-resistant E. coli isolates were positive for blaCTX-M-199 and two of them were positive for carbapenemase-producing gene blaNDM-5. Multivariable logistic regression model revealed that variable "secondary/tertiary non-profit hospital nearby" was significantly (p < 0.05) associated with isolation of AR Enterobacteriaceae from the shared bikes around the Metro stations. Low AR rates of Enterobacteriaceae observed in this study suggested the risk of dissemination of AR-Enterobacteriaceae via shared bikes is limited. However, we identified hospitals as a risk factor for the dissemination of AR Enterobacteriaceae among shared bike users. More attention should be paid to both comprehensive hygiene managements in the surrounding environment of hospitals and the increasing of public awareness on the personal hygienic habits.


Assuntos
Ciclismo , Resistência Microbiana a Medicamentos , Enterobacteriaceae/isolamento & purificação , Fômites , Antibacterianos/farmacologia , Pequim , Enterobacteriaceae/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana
14.
Food Microbiol ; 84: 103256, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421788

RESUMO

Cronobacter spp. are opportunistic pathogens that must be controlled in infant powder manufacturing plants. This study evaluated the spread of Cronobacter cells via contact surfaces within a dairy manufacturing environment. Transfer rates of Cronobacter spp. were determined from vectors for transmission including moveable fomites (e.g. trolley wheels and boots) and gloved hands to various types of recipient surfaces (stainless steel, linoleum and resin-coated concrete) typical for dairy manufacturing environments. Overall, with a starting inoculum of 106 CFU/mL, approximately 104 CFU/mL Cronobacter cells were transferred from each fomite onto each recipient surface during the initial transfer event. Gloved hands transferred the highest number of Cronobacter cells, followed by polyvinylchloride boots and then polyurethane trolley wheels. We demonstrate, using a combination of experimental data and uncertainty analysis, that if a movable fomite (boots or trolley wheels), or gloves became contaminated, Cronobacter could be spread over a wide area within a manufacturing plant. To the authors' knowledge, this is the first quantitative estimation of the spread of Cronobacter within a dairy manufacturing plant, that can also be practically applied as a tool for providing information in making risk management decisions. In particular, the estimation of spread suggests areas for cleaning and sanitation within a dairy manufacturing environment during a contamination event.


Assuntos
Cronobacter/isolamento & purificação , Indústria de Laticínios/instrumentação , Contaminação de Equipamentos , Pisos e Cobertura de Pisos , Fômites/microbiologia , Contaminação de Alimentos/análise , Qualidade de Produtos para o Consumidor , Indústria de Laticínios/normas , Luvas Protetoras/microbiologia , Aço Inoxidável , Tato
15.
J Hosp Infect ; 103(4): 363-374, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31369807

RESUMO

There is increasing evidence that the hospital surface environment contributes to the spread of pathogens. However, evidence on how best to sample these surfaces is inconsistent and there is no guidance or legislation in place on how to do this. The aim of this review was to assess current literature on surface sampling methodologies, including the devices used, processing methods, and the environmental and biological factors that might influence results. Studies published prior to March 2019 were selected using relevant keywords from ScienceDirect, Web of Science, and PubMed. Abstracts were reviewed and all data-based studies in peer-reviewed journals in the English language were included. Microbiological air and water sampling in the hospital environment were not included. Although the numbers of cells or virions recovered from hospital surface environments were generally low, the majority of surfaces sampled were microbiologically contaminated. Of the organisms detected, multidrug-resistant organisms and clinically significant pathogens were frequently isolated and could, therefore, present a risk to vulnerable patients. Great variation was found between methods and the available data were incomplete and incomparable. Available literature on sampling methods demonstrated deficits with potential improvements for future research. Many of the studies included in the review were laboratory-based and not undertaken in the real hospital environment where sampling recoveries could be affected by the many variables present in a clinical environment. It was therefore difficult to draw overall conclusions; however, some recommendations for the design of routine protocols for surface sampling of healthcare environments can be made.


Assuntos
Microbiologia Ambiental , Fômites/microbiologia , Fômites/virologia , Instalações de Saúde , Técnicas Microbiológicas/métodos , Manejo de Espécimes/métodos , Humanos , Técnicas Microbiológicas/instrumentação , Manejo de Espécimes/instrumentação
16.
J Hosp Infect ; 103(4): 375-381, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31454512

RESUMO

Clostridioides difficile, a spore-forming bacillus, is a major cause of healthcare-associated infection, and can survive for prolonged periods in the inanimate environment. Environmental sampling to detect C. difficile is not routine but may be undertaken as part of outbreak management and during research projects. We conducted a literature search covering the period between 1980 and 2018 to review methods for the detection of this pathogen in the environment. There are many acceptable sampling methods used for environmental screening, including contact plates, cotton swabs, flocked swabs and sponges. Most recent studies suggest that sponges are the most effective method of sampling and have the added benefit of being capable of sampling larger and curved areas. Culture methods are the most common laboratory method of detecting C. difficile from environmental samples. However, the results are variable depending on the type of agar used and the turnaround times can be long. Molecular methods such as real-time polymerase chain reaction (RT-PCR), although more commonly used to detect C. difficile from faecal specimens, has been used with varying degrees of success in environmental sampling. Further studies are needed to determine whether molecular techniques could offer a more reliable, faster method of environmental sampling, giving infection prevention and control teams more reassurance that patients are being placed in adequately decontaminated hospital environments.


Assuntos
Clostridium difficile/isolamento & purificação , Microbiologia Ambiental , Fômites/microbiologia , Instalações de Saúde , Técnicas Microbiológicas/métodos , Manejo de Espécimes/métodos
19.
Infect Control Hosp Epidemiol ; 40(6): 717-720, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30973128

RESUMO

Bacterial community composition and presence of antibiotic resistance genes (mecA, tetK, and vanA) on personal mobile devices (PMDs) of nurses in intensive care units (ICUs) were evaluated. Antibiotic resistance genes on PMDs decreased at the end of the shift, and a several microbial genera changed.


Assuntos
Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Telefone Celular , Farmacorresistência Bacteriana/genética , Unidades de Terapia Intensiva , Contaminação de Equipamentos , Fômites , Hospitais Universitários , Humanos , Testes de Sensibilidade Microbiana , Enfermeiras e Enfermeiros
20.
Viruses ; 11(4)2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970559

RESUMO

Background: Massilia virus (MASV) is a phlebovirus isolated from Phlebotomus perniciosus in various regions of southwestern Europe. It is closely related to human pathogens such as Toscana virus and sandfly fever Naples virus. The natural cycle of phleboviruses is poorly understood. Indeed, experimental studies demonstrate that transovarial and sexual transmission are not efficient enough for the maintenance of the virus in nature and to date there is no convincing evidence that a species of vertebrates is the reservoir of the virus. Here, we studied various transmission routes of MASV taking advantage of experimental colonies representing different species of sand flies. Methodology/Principal findings: In P. perniciosus, four sources of infection were compared: (i) Virus-seeded larval food to the first instar larvae (L1), or (ii) to the fourth instar larvae (L4), (iii) virus-seeded blood meal to adult females, and (iv) virus-seeded sugar meal to adults of both sexes. From 875 adults emerged from infected L1 and L4, only three were positive. In females infected by bloodmeal the infection rate was high before defecation, then it decreased drastically; MASV RNA was detected in only 5 out of 27 post-defecation. Surprisingly, the most efficient route of infection was observed after intake of virus-seeded sugar meal: 72% of females (79/110) and 52% of males (51/99) were found to be MASV RNA-positive. In addition, MASV-infected sandflies regurgitated virus particules into the sugar drop and MASV RNA was detectable in this drop for at least 24 h after regurgitation. MASV RNA was detected in about one third of the P. perniciosus exposed to this sugar drop contaminated by regurgitation. Sugar meal infection was also tested with six other species of sand flies. In males, there were no significant differences in infection rates when compared to P. perniciosus. In females, most species tested showed high infection rate at the beginning but then significant gradual decrease in infection rate during the experiment. Conclusions/Significance: We present the first description of arboviral infection of a dipteran vector using sugar meal. In all seven sand fly species tested, MASV was detected for two weeks post-infection. Our results showed that MASV can be transmitted between P. perniciosus either through co-feeding or via an infected sugar source such as plant sap. These newly described routes of horizontal transmission may play an important role in the circulation of phleboviruses in nature.


Assuntos
Comportamento Alimentar , Contaminação de Alimentos , Insetos Vetores/virologia , Febre por Flebótomos/transmissão , Phlebovirus/isolamento & purificação , Psychodidae/virologia , Animais , Fômites/virologia , Insetos Vetores/fisiologia , Refeições , Phlebovirus/crescimento & desenvolvimento , Psychodidae/fisiologia , Açúcares
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