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1.
BMC Vet Res ; 17(1): 328, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645426

RESUMO

BACKGROUND: Chlamydia-like organisms (CLO) have been found to be present in many environmental niches, including human sewage and agricultural run-off, as well as in a number of aquatic species worldwide. Therefore, monitoring their presence in sentinel wildlife species may be useful in assessing the wider health of marine food webs in response to habitat loss, pollution and disease. We used nasal swabs from live (n = 42) and dead (n = 50) pre-weaned grey seal pups and samples of differing natal substrates (n = 8) from an off-shore island devoid of livestock and permanent human habitation to determine if CLO DNA is present in these mammals and to identify possible sources. RESULTS: We recovered CLO DNA from 32/92 (34.7%) nasal swabs from both live (n = 17) and dead (n = 15) seal pups that clustered most closely with currently recognised species belonging to three chlamydial families: Parachlamydiaceae (n = 22), Rhabdochlamydiaceae (n = 6), and Simkaniaceae (n = 3). All DNA positive sediment samples (n = 7) clustered with the Rhabdochlamydiaceae. No difference was found in rates of recovery of CLO DNA in live versus dead pups suggesting the organisms are commensal but their potential as opportunistic secondary pathogens could not be determined. CONCLUSION: This is the first report of CLO DNA being found in marine mammals. This identification warrants further investigation in other seal populations around the coast of the UK and in other areas of the world to determine if this finding is unique or more common than shown by this data. Further investigation would also be warranted to determine if they are present as purely commensal organisms or whether they could also be opportunistic pathogens in seals, as well as to investigate possible sources of origin, including whether they originated as a result of anthropogenic impacts, including human waste and agricultural run-off.


Assuntos
Chlamydiaceae/isolamento & purificação , Microbiologia Ambiental , Cavidade Nasal/microbiologia , Focas Verdadeiras/microbiologia , Animais , Chlamydiaceae/classificação , Chlamydiaceae/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Humanos , Filogenia , Escócia , Resíduos
2.
PLoS Pathog ; 17(9): e1009883, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34492088

RESUMO

SARS-CoV-2 infection outbreaks in minks have serious implications associated with animal health and welfare, and public health. In two naturally infected mink farms (A and B) located in Greece, we investigated the outbreaks and assessed parameters associated with virus transmission, immunity, pathology, and environmental contamination. Symptoms ranged from anorexia and mild depression to respiratory signs of varying intensity. Although the farms were at different breeding stages, mortality was similarly high (8.4% and 10.0%). The viral strains belonged to lineages B.1.1.218 and B.1.1.305, possessing the mink-specific S-Y453F substitution. Lung histopathology identified necrosis of smooth muscle and connective tissue elements of vascular walls, and vasculitis as the main early key events of the acute SARS-CoV-2-induced broncho-interstitial pneumonia. Molecular investigation in two dead minks indicated a consistently higher (0.3-1.3 log10 RNA copies/g) viral load in organs of the male mink compared to the female. In farm A, the infected farmers were responsible for the significant initial infection of 229 out of 1,000 handled minks, suggesting a very efficient human-to-mink transmission. Subsequent infections across the sheds wherein animals were being housed occurred due to airborne transmission. Based on a R0 of 2.90 and a growth rate equal to 0.293, the generation time was estimated to be 3.6 days, indicative of the massive SARS-CoV-2 dispersal among minks. After the end of the outbreaks, a similar percentage of animals were immune in the two farms (93.0% and 93.3%), preventing further virus transmission whereas, viral RNA was detected in samples collected from shed surfaces and air. Consequently, strict biosecurity is imperative during the occurrence of clinical signs. Environmental viral load monitoring, in conjunction with NGS should be adopted in mink farm surveillance. The minimum proportion of minks that need to be immunized to avoid outbreaks in farms was calculated at 65.5%, which is important for future vaccination campaigns.


Assuntos
COVID-19/veterinária , Vison/virologia , Animais , COVID-19/epidemiologia , COVID-19/genética , COVID-19/transmissão , Surtos de Doenças/veterinária , Microbiologia Ambiental , Fazendas , Feminino , Grécia/epidemiologia , Humanos , Masculino , Vison/genética , Exposição Ocupacional , Zoonoses Virais/transmissão , Zoonoses Virais/virologia
3.
J Med Microbiol ; 70(9)2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34586052

RESUMO

Vibrio species are important environmental-related bacteria responsible for diverse infections in humans due to consumption of contaminated water and seafood in underdeveloped areas of the world. This study aimed to investigate the frequency of antimicrobial resistance genes in 577 sequenced Vibrio cholerae, Vibrio parahaemolyticus and Vibrio vulnificus strains isolated in Latin American countries available at the NCBI Pathogen Detection database and to determine the sequence type (ST) of the strains. Almost all strains studied (99.8%) carried at least one antimicrobial resistance gene, while 54.2 % presented a multidrug-resistance profile. The Vibrio strains exhibited genotypic resistance to 11 antimicrobial classes and almG, varG, and catB9, which confer resistance to antibiotic peptides, ß-lactams and amphenicols, respectively, were the most detected genes. Vibrio parahaemolyticus and V. vulnificus showed a broad diversity of STs. Vibrio cholerae strains isolated in Haiti after 2010's earthquake presented the highest diversity and amount of resistance genes in the set of strains analysed and mostly belonged to ST69. In conclusion, the detection of resistance genes from 11 antimicrobial classes and the high number of multidrug-resistant Vibrio species strains emphasize that Latin American public health authorities should employ more efficient control measures and that special attention should be given for the rational use of antimicrobials in human therapy and aquaculture, since the consumption of contaminated water and seafood with resistant Vibrio may result in human infections difficult to be treated.


Assuntos
Farmacorresistência Bacteriana/genética , Frequência do Gene , Vibrio/genética , Sequenciamento Completo do Genoma , Animais , Farmacorresistência Bacteriana Múltipla/genética , Microbiologia Ambiental , Microbiologia de Alimentos , Humanos , América Latina , Vibrio/classificação , Vibrio/efeitos dos fármacos
4.
Mycoses ; 64(11): 1354-1365, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34558115

RESUMO

BACKGROUND: Mutations in cyp51A gene are known as main mechanisms of azole resistance in Aspergillus fumigatus, whereas azole-susceptible strains also carry cyp51A mutations (polymorphisms). The polymorphisms found in Europe mainly consist of two combinations of mutations, that is combinations of five single-nucleotide polymorphisms (SNPs) of cyp51A, referred to as cyp51A-5SNPs, and combinations of three SNPs of cyp51A, referred to as cyp51A-3SNPs. Few studies have compared the distributions of cyp51A polymorphisms between different regions. OBJECTIVES: The aim of this study was to investigate the regional differences of cyp51A polymorphisms. METHODS: We compared the proportions of cyp51A polymorphisms in clinical and environmental strains isolated in various countries, and analysed the strains phylogenetically using short tandem repeats (STRs) and whole-genome sequence (WGS). RESULTS: Among the Japanese strains, 15 out of 98 (15.3%) clinical strains and 8 out of 95 (8.4%) environmental strains had cyp51A polymorphisms. A mutation of cyp51AN248K was the most prevalent polymorphism in both clinical (n = 14, 14.3%) and environmental strains (n = 3, 3.2%). Only one environmental strain harboured cyp51A-5SNPs, which was reported to be the most prevalent in Europe. For phylogenetic analyses using STRs and WGS, 183 and 134 strains, respectively, were employed. They showed that most of the strains with cyp51AN248K clustered in the clades different from those of the strains with cyp51A-5SNPs and cyp51A-3SNPs as well as from those with TR34 /L98H mutations. CONCLUSIONS: This study suggests that there are genetic differences between cyp51A polymorphisms of A. fumigatus in Japan and Europe.


Assuntos
Aspergillus fumigatus/genética , Sistema Enzimático do Citocromo P-450/genética , Proteínas Fúngicas/genética , Aspergilose Pulmonar Invasiva/microbiologia , Polimorfismo de Nucleotídeo Único , Aspergilose Pulmonar/microbiologia , Animais , Antifúngicos/farmacologia , Aspergillus fumigatus/classificação , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/patogenicidade , Bombyx/microbiologia , Doença Crônica , Microbiologia Ambiental , Europa (Continente) , Genótipo , Humanos , Japão , Testes de Sensibilidade Microbiana , Mutação , Filogenia , Virulência , Sequenciamento Completo do Genoma
5.
Biosensors (Basel) ; 11(9)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34562907

RESUMO

Escherichia coli O157:H7 and Staphylococcus aureus are common pathogens. Gram-negative bacteria, such as E. coli, contain high concentrations of endogenous peroxidases, whereas Gram-positive bacteria, such as S. aureus, possess abundant endogenous catalases. Colorless 3,5,3',5'-tetramethyl benzidine (TMB) changes to blue oxidized TMB in the presence of E. coli and a low concentration of H2O2 (e.g., ~11 mM) at pH of 3. Moreover, visible air bubbles containing oxygen are generated after S. aureus reacts with H2O2 at a high concentration (e.g., 180 mM) at pH of 3. A novel method for rapidly detecting the presence of bacteria on the surfaces of samples, on the basis of these two endogenous enzymatic reactions, was explored. Briefly, a cotton swab was used for collecting bacteria from the surfaces of samples, such as tomatoes and door handles, then two-step endogenous enzymatic reactions were carried out. In the first step, a cotton swab containing bacteria was immersed in a reagent comprising H2O2 (11.2 mM) and TMB for 25 min. In the second step, the swab was dipped further in H2O2 (180 mM) at pH 3 for 5 min. Results showed that the presence of Gram-negative bacteria, such as E. coli with a cell number of ≥ ~105, and Gram-positive bacteria, such as S. aureus with a cell number of ≥ ~106, can be visually confirmed according to the appearance of the blue color in the swab and the formation of air bubbles in the reagent solution, respectively, within ~30 min. To improve visual sensitivity, we dipped the swab carrying the bacteria in a vial containing a growth broth, incubated it for ~4 h, and carried out the two-stage reaction steps. Results showed that bluish swabs resulting from the presence of E. coli O157: H7 with initial cell numbers of ≥ ~34 were obtained, whereas air bubbles were visible in the samples containing S. aureus with initial cell numbers of ≥ ~8.5 × 103.


Assuntos
Bactérias , Microbiologia Ambiental , Escherichia coli O157 , Staphylococcus aureus
6.
Nat Microbiol ; 6(10): 1259-1270, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34580444

RESUMO

Understanding how multidrug-resistant Enterobacterales (MDRE) are transmitted in low- and middle-income countries (LMICs) is critical for implementing robust policies to curb the increasing burden of antimicrobial resistance (AMR). Here, we analysed samples from surgical site infections (SSIs), hospital surfaces (HSs) and arthropods (summer and winter 2016) to investigate the incidence and transmission of MDRE in a public hospital in Pakistan. We investigated Enterobacterales containing resistance genes (blaCTX-M-15, blaNDM and blaOXA-48-like) for identification, antimicrobial susceptibility testing and whole-genome sequencing. Genotypes, phylogenetic relationships and transmission events for isolates from different sources were investigated using single-nucleotide polymorphism (SNP) analysis with a cut-off of ≤20 SNPs. Escherichia coli (14.3%), Klebsiella pneumoniae (10.9%) and Enterobacter cloacae (16.3%) were the main MDRE species isolated. The carbapenemase gene blaNDM was most commonly detected, with 15.5%, 15.1% and 13.3% of samples positive in SSIs, HSs and arthropods, respectively. SNP (≤20) and spatiotemporal analysis revealed linkages in bacteria between SSIs, HSs and arthropods supporting the One Health approach to underpin infection control policies across LMICs and control AMR.


Assuntos
Vetores Artrópodes/microbiologia , Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/isolamento & purificação , Infecção da Ferida Cirúrgica/microbiologia , Animais , Antibacterianos/farmacologia , Vetores Artrópodes/classificação , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/classificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/transmissão , Microbiologia Ambiental , Variação Genética , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Paquistão/epidemiologia , Filogenia , Plasmídeos/genética , Prevalência , Estações do Ano , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/transmissão , beta-Lactamases/genética
7.
Sci Rep ; 11(1): 15911, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354124

RESUMO

The microbiome composition of living organisms is closely linked to essential functions determining the fitness of the host for thriving and adapting to a particular ecosystem. Although multiple factors, including the developmental stage, the diet, and host-microbe coevolution have been reported to drive compositional changes in the microbiome structures, very few attempts have been made to disentangle their various contributions in a global approach. Here, we focus on the emerald ash borer (EAB), an herbivorous pest and a real threat to North American ash tree species, to explore the responses of the adult EAB gut microbiome to ash leaf properties, and to identify potential predictors of EAB microbial variations. The relative contributions of specific host plant properties, namely bacterial and fungal communities on leaves, phytochemical composition, and the geographical coordinates of the sampling sites, to the EAB gut microbial community was examined by canonical analyses. The composition of the phyllosphere microbiome appeared to be a strong predictor of the microbial community structure in EAB guts, explaining 53 and 48% of the variation in fungi and bacteria, respectively. This study suggests a potential covariation of the microorganisms associated with food sources and the insect gut microbiome.


Assuntos
Besouros/microbiologia , Fraxinus/microbiologia , Microbioma Gastrointestinal/fisiologia , Animais , Bactérias , Meio Ambiente , Microbiologia Ambiental , Insetos , Larva/fisiologia , Microbiota , Compostos Fitoquímicos/farmacologia , Folhas de Planta/metabolismo , Árvores/microbiologia
8.
Mycoses ; 64(11): 1328-1333, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34411353

RESUMO

BACKGROUND: Exophiala is the main genus of black fungi comprising numerous opportunistic species. Data on antifungal susceptibility of Exophiala isolates are limited, while infections are potentially fatal. MATERIALS AND METHODS: In vitro activities of eight antifungal drugs (AMB, five azoles, two echinocandins) against 126 clinical (n = 76) and environmental (n = 47) isolates from around the world were investigated. E. oligosperma (n = 58), E. spinifera (n = 33), E. jeanselmei (n = 14) and E. xenobiotica (n = 21) were included in our dataset. RESULTS: The resulting MIC90 s of all strains were as follows, in increasing order: posaconazole 0.063 µg/ml, itraconazole 0.125 µg/ml, voriconazole and amphotericin B 1 µg/ml, isavuconazole 2 µg/ml, micafungin and caspofungin 4 µg/ml, and fluconazole 64 µg/ml. Posaconazole, itraconazole and micafungin were the drugs with the best overall activity against Exophiala species. Fluconazole could not be considered as a treatment choice. No significant difference could be found among antifungal drug activities between these four species, neither in clinical nor in environmental isolates. CONCLUSION: Antifungal susceptibility data for Exophiala spp. are crucial to improve the management of this occasionally fatal infection and the outcome of its treatment.


Assuntos
Antifúngicos/farmacologia , Microbiologia Ambiental , Exophiala/efeitos dos fármacos , Feoifomicose/microbiologia , Animais , Antifúngicos/classificação , Antifúngicos/uso terapêutico , Exophiala/classificação , Exophiala/genética , Humanos , Testes de Sensibilidade Microbiana , Feoifomicose/tratamento farmacológico
9.
Nat Microbiol ; 6(9): 1118-1128, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34446927

RESUMO

Environmental bacteria, such as Streptomyces spp., produce specialized metabolites that are potent antibiotics and therapeutics. Selected specialized antimicrobials are co-produced and function together synergistically. Co-produced antimicrobials comprise multiple chemical classes and are produced by a wide variety of bacteria in different environmental niches, suggesting that their combined functions are ecologically important. Here, we highlight the exquisite mechanisms that underlie the simultaneous production and functional synergy of 16 sets of co-produced antimicrobials. To date, antibiotic and antifungal discovery has focused mainly on single molecules, but we propose that methods to target co-produced antimicrobials could widen the scope and applications of discovery programs.


Assuntos
Antibacterianos/biossíntese , Bactérias/química , Bactérias/metabolismo , Antibacterianos/farmacologia , Bactérias/classificação , Bactérias/genética , Microbiologia Ambiental
10.
Environ Sci Technol ; 55(15): 10210-10223, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34286966

RESUMO

Real-time quantitative polymerase chain reaction (qPCR) and digital PCR (dPCR) methods have revolutionized environmental microbiology, yielding quantitative organism-specific data of nucleic acid targets in the environment. Such data are essential for characterizing interactions and processes of microbial communities, assessing microbial contaminants in the environment (water, air, fomites), and developing interventions (water treatment, surface disinfection, air purification) to curb infectious disease transmission. However, our review of recent qPCR and dPCR literature in our field of health-related environmental microbiology showed that many researchers are not reporting necessary and sufficient controls and methods, which would serve to strengthen their study results and conclusions. Here, we describe the application, utility, and interpretation of the suite of controls needed to make high quality qPCR and dPCR measurements of microorganisms in the environment. Our presentation is organized by the discrete steps and operations typical of this measurement process. We propose systematic terminology to minimize ambiguity and aid comparisons among studies. Example schemes for batching and combining controls for efficient work flow are demonstrated. We describe critical reporting elements for enhancing data credibility, and we provide an element checklist in the Supporting Information. Additionally, we present several key principles in metrology as context for laboratories to devise their own quality assurance and quality control reporting framework. Following the EMMI guidelines will improve comparability and reproducibility among qPCR and dPCR studies in environmental microbiology, better inform engineering and public health actions for preventing disease transmission through environmental pathways, and for the most pressing issues in the discipline, focus the weight of evidence in the direction toward solutions.


Assuntos
Microbiologia Ambiental , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes
11.
Fungal Biol ; 125(8): 609-620, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34281654

RESUMO

Subterranean Cultural Heritage sites are frequently subject to biological colonization due to the high levels of humidity, even in conditions of low irradiance and oligotrophy. Here microorganisms form complex communities that may be dangerous through mineral precipitation, through the softening of materials or causing frequent surface discolorations. A reduction of contamination's sources along with the control of microclimatic conditions and biocide treatments (overall performed with benzalkonium chloride) are necessary to reduce microbial growths. Dark discolorations have been recorded in the painted Etruscan tombs of Tarquinia, two of which have been analyzed to collect taxonomical, physiological, and ecological information. Eighteen dark-pigmented fungi were isolated among a wider culturable fraction: nine from blackening areas and nine from door sealings, a possible route of contamination. Isolates belonged to three major groups: Chaetothyriales, Capnodiales (Family Cladosporiaceae), and Acremonium-like fungi. Exophiala angulospora and Cyphellophora olivacea, a novelty for hypogea, were identified, while others need further investigations as possible new taxa. The metabolic skills of the detected species showed their potential dangerousness for the materials. Their tolerance to benzalkonium chloride-based products suggested a certain favouring effect through the decreasing competitiveness of less resistant species. The type of covering of the dromos may influence the risk of outer contamination. Fungal occurrence can be favoured by root penetration.


Assuntos
Biodiversidade , Farmacorresistência Fúngica , Microbiologia Ambiental , Fungos , Ascomicetos/efeitos dos fármacos , Ascomicetos/fisiologia , Compostos de Benzalcônio/farmacologia , Exophiala/efeitos dos fármacos , Exophiala/fisiologia , Fungos/efeitos dos fármacos , Fungos/isolamento & purificação , Itália
12.
Zoonoses Public Health ; 68(6): 666-676, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34240552

RESUMO

Real-time PCR analysis of environmental samples (dust and aerosols) is an easy tool to investigate the presence of Coxiella burnetii in the farm environment. The aim of this study was to assess the distribution of C. burnetii DNA in dust collected inside animal premises from 272 small ruminant farms in Bizkaia (northern Spain), a region with recent reports of human Q fever cases and outbreaks. Within each farm, 5 samples of dust were collected from difference surfaces, and data on animal census, management procedures, characteristics of the premises and geographic location were collected. Real-time PCR analysis of the dust samples detected presence of C. burnetii DNA in 98 farms (36.0%), flock-prevalence being higher in sheep (38.9%) or mixed ovine-caprine production systems (36.8%), compared to goats (25.0%). Larger bacterial burdens were observed in mixed farms, compared to sheep (p < .05). Single nucleotide polymorphism (SNP) analysis identified 5 different genotypes, with SNP8 being the predominant genotype (73%), followed by SNP6 (11%), SNP2 (9%), SNP4 (5%) and SNP1 (2%). Proportion of farms where C. burnetii DNA was detected differed among the different agricultural counties, and a higher proportion of C. burnetii DNA positive farms was associated with the occurrence of recent human Q fever outbreaks at several geographical locations. Dust sampling in domestic ruminant farms coupled with real-time PCR to screen for the presence of C. burnetii and estimate bacterial load can be a useful tool to identify herds and regions with high prevalence, define priority actions and monitor the effect of control measures. If combined with molecular genotyping and spatial distribution maps, it can help to identify farm contamination sources and trace the origin of human outbreaks.


Assuntos
Coxiella burnetii/isolamento & purificação , Poeira , Microbiologia Ambiental , Cabras/microbiologia , Febre Q/epidemiologia , Ovinos/microbiologia , Animais , Zoonoses Bacterianas/epidemiologia , Zoonoses Bacterianas/microbiologia , Coxiella burnetii/genética , Doenças Endêmicas , Genótipo , Abrigo para Animais , Humanos , Modelos Logísticos , Reação em Cadeia da Polimerase em Tempo Real , Espanha/epidemiologia
13.
Microb Biotechnol ; 14(5): 1878-1880, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34311495

RESUMO

The Nagoya Protocol on Access and Benefit-sharing (https://www.cbd.int/abs/), primarily designed for vascular plant and animal resources, is also extended to the use of microbial resources, but its application to the microbiological realm has raised many doubts and provoked criticisms. This is because of the particularities of microbial ecology and the technical and legal difficulties encompassed in its application.


Assuntos
Microbiologia Ambiental , Animais , Biodiversidade , Conservação dos Recursos Naturais
14.
Math Biosci ; 340: 108666, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34310932

RESUMO

Clostridioides difficile, formerly Clostridium difficile, is the leading cause of infectious diarrhea and one of the most common healthcare acquired infections in United States hospitals. C. difficile persists well in healthcare environments because it forms spores that can survive for long periods of time and can be transmitted to susceptible patients through contact with contaminated hands and fomites, objects or surfaces that can harbor infectious agents. Fomites can be classified as high-touch or low-touch based on the frequency they are contacted. The mathematical model in this study investigates the relative contribution of high-touch and low-touch fomites on new cases of C. difficile colonization among patients of a hospital ward. The dynamics of transmission are described by a system of ordinary differential equations representing four patient population classes and two pathogen environmental reservoirs. Parameters that have a significant effect on incidence, as determined by a global sensitivity analysis, are varied in stochastic simulations of the system to identify feasible strategies to prevent disease transmission. Results indicate that on average, under one-quarter of asymptomatically colonized patients are exposed to C. difficile via low-touch fomites. In comparison, over three-quarters of colonized patients are colonized through high-touch fomites, despite additional cleaning of high-touch fomites. Increased contacts with high-touch fomites increases the contribution of these fomites to the incidence of colonized individuals and decreasing the duration of a hospital visit reduces the amount of pathogen in the environment. Thus, enhanced efficacy of disinfection upon discharge and extra cleaning of high-touch fomites, reduced contact with high-touch fomites, and higher discharge rates, among other control measures, could lead to a decrease in the incidence of colonized individuals.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Infecção Hospitalar , Modelos Biológicos , Tato , Infecções por Clostridium/transmissão , Infecção Hospitalar/transmissão , Atenção à Saúde/estatística & dados numéricos , Microbiologia Ambiental , Humanos
15.
PLoS One ; 16(7): e0254068, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34214115

RESUMO

Prevalence of toxigenic Vibrio cholerae O1 in aquatic reservoirs in Bangladesh apparently increases coinciding with the occurrence of seasonal cholera epidemics. In between epidemics, these bacteria persist in water mostly as dormant cells, known as viable but non-culturable cells (VBNC), or conditionally viable environmental cells (CVEC), that fail to grow in routine culture. CVEC resuscitate to active cells when enriched in culture medium supplemented with quorum sensing autoinducers CAI-1 or AI-2 which are signal molecules that regulate gene expression dependent on cell density. V. cholerae O1 mutant strains with inactivated cqsS gene encoding the CAI-1 receptor has been shown to overproduce AI-2 that enhance CVEC resuscitation in water samples. Since V. cholerae non-O1 non-O139 (non-cholera-vibrios) are abundant in aquatic ecosystems, we identified and characterized naturally occurring variant strains of V. cholerae non-O1 non-O139 which overproduce AI-2, and monitored their co-occurrence with V. cholerae O1 in water samples. The nucleotide sequence and predicted protein products of the cqsS gene carried by AI-2 overproducing variant strains showed divergence from that of typical V. cholerae O1 or non-O1 strains, and their culture supernatants enhanced resuscitation of CVEC in water samples. Furthermore, prevalence of V. cholerae O1 in the aquatic environment was found to coincide with an increase in AI-2 overproducing non-O1 non-O139 strains. These results suggest a possible role of non-cholera vibrios in the environmental biology of the cholera pathogen, in which non-O1 non-O139 variant strains overproducing AI-2 presumably contribute in resuscitation of the latent pathogen, leading to seasonal cholera epidemics. Importance. Toxigenic Vibrio cholerae which causes seasonal epidemics of cholera persists in aquatic reservoirs in endemic areas. The bacteria mostly exist in a dormant state during inter-epidemic periods, but periodically resuscitate to the active form. The resuscitation is enhanced by signal molecules called autoinducers (AIs). Toxigenic V. cholerae can be recovered from water samples that normally test negative for the organism in conventional culture, by supplementing the culture medium with exogenous AIs. V. cholerae belonging to the non-O1 non-O139 serogroups which do not cause cholera are also abundant in natural waters, and they are capable of producing AIs. In this study we characterized V. cholerae non-O1 non-O139 variant strains which overproduce an autoinducer called AI-2, and found that the abundance of the cholera pathogen in aquatic reservoirs correlates with an increase in the AI-2 overproducing strains. Our results suggest a probable role of these variant strains in the environmental biology and epidemiology of toxigenic V. cholerae, and may lead to novel means for surveillance, prevention and control of cholera.


Assuntos
Microbiologia Ambiental , Variação Genética , Homosserina/análogos & derivados , Vibrio cholerae O1/genética , Sequência de Aminoácidos , Proteínas de Bactérias/química , Bangladesh , Genoma Bacteriano , Homosserina/genética , Lactonas , Luminescência , Mutação/genética , Prevalência , Microbiologia da Água
16.
J Environ Public Health ; 2021: 9976064, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34221030

RESUMO

Background: Antibiotic resistance in bacteria is a major global health challenge. Reports on the prevalence of multidrug-resistant P. aeruginosa, a common pathogenic bacterium implicated in nosocomial infections and poultry diseases, are limited in Ghana. This study therefore sought to determine the prevalence of P. aeruginosa from hospitals, poultry farms, and environmental samples from the Ashanti region of Ghana. Methodology. Stool, urine, and blood samples from 364 patients from two hospitals in the Ashanti region of Ghana were randomly sampled. P. aeruginosa was isolated and confirmed using routine selective media and PCR-based oprL gene amplification. The Kirby-Bauer disk diffusion method employing EUCAST breakpoint values was used to identify multidrug-resistant strains. The occurrence of common antibiotic inactivating enzymes and resistance encoding genes and the assessment of strain efflux capacity were investigated with double disc synergy test (DDST), imipenem-EDTA synergy test, phenylboronic acid test, D-test, routine PCR, and ethidium bromide agar-cartwheel method. Results: A total of 87 (9.7%, n = 87/900) P. aeruginosa isolates were confirmed from the samples. 75% (n = 65/87) were resistant to more than one group of antipseudomonal agents, while 43.6% (n = 38/87) were multidrug-resistant (MDR). High prevalence of extended spectrum ß-lactamases (84.2%), metallo-ß-lactamases (34.1%), and AmpC inducible cephalosporinases (50%) was observed in the MDR strains. About 57.8% of the MDR strains showed moderate to very high efflux capacity. Class 1 integrons were detected in 89.4% of the MDR isolates but ß-lactamase encoding genes (bla SHV , bla TEM , bla CTX-M , bla VIM , and bla IMP ) were not detected. Conclusion: Surveillance of antibiotic-resistant strains of bacteria should be routinely conducted in clinical and veterinary practice in Ghana to inform selection of antibiotics for therapeutic use.


Assuntos
Resistência a Múltiplos Medicamentos , Pseudomonas aeruginosa , Animais , Antibacterianos/farmacologia , Resistência a Múltiplos Medicamentos/genética , Microbiologia Ambiental , Fazendas , Genótipo , Gana/epidemiologia , Hospitais , Humanos , Fenótipo , Aves Domésticas , Prevalência , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação
17.
J Environ Public Health ; 2021: 7682042, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34285698

RESUMO

Background: The hospital environment, especially surfaces and medical devices, is a source of contamination for patients. Objective: This study carried out, to the best of our knowledge, for the first time at Taza Hospital in Morocco aimed to assess the microbiological quality of surfaces and medical devices in surgical departments and to evaluate the disinfection procedure in time and space. Methods: Samples were taken by swabbing after cleaning the hospital surface or medical device, to isolate and identify germs which were inoculated on semiselective culture media then identified by standard biochemical and physiological tests, using the analytical profile index (API) galleries. Moreover, the association rules extraction model between sites on the one hand and germs on the other hand was used for sampling. Results: The study showed that 83% of the samples have been contaminated after biocleaning. The most contaminated services have been men's and women's surgeries. 62% of isolated germs have been identified as Gram-positive bacteria, 29% as Gram-negative bacteria, and 9% as fungi. Concerning the association rules extraction model, a strong association between some contaminated sites and the presence of germ has been found, such as the association between wall and nightstand and door cuff, meaning that the wall and nightstand contamination is systematically linked to that of the door cuff. The disinfection procedure efficacy evaluation has enabled suggesting renewing it each 4 h. Conclusion: Microbiological monitoring of surfaces is necessary at hospital level through the use of the association rule extraction model, which is very important to optimize the sampling, cleaning, and disinfection site scenarios of the most contaminated ones.


Assuntos
Microbiologia Ambiental , Monitoramento Ambiental , Hospitais , Desinfecção/normas , Monitoramento Ambiental/métodos , Feminino , Humanos , Masculino , Marrocos
18.
Sci Rep ; 11(1): 13966, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234223

RESUMO

Shiga toxigenic strains of E. coli (STEC) known to be etiological agents for diarrhea were screened for their incidence/occurrence in selected abattoirs sources in Osogbo metropolis of Osun State, Nigeria using a randomized block design. Samples were plated directly on selective and differential media and E. coli isolates. Multiplex PCR analysis was used to screen for the presence of specific virulence factors. These were confirmed serologically as non-O157 STEC using latex agglutination serotyping kit. Sequence analysis of PCR products was performed on a representative isolate showing the highest combination of virulence genes using the 16S gene for identification purposes only. Results showed that the average cfu/cm2 was significantly lower in the samples collected at Sekona-2 slaughter slab compared with those collected at Al-maleek batch abattoir and Sekona-1 slaughter slab in ascending order at P = 0.03. Moreover, the average cfu/cm2 E. coli in samples collected from butchering knife was significantly lower when compared with that of the workers' hand (P = 0.047) and slaughtering floor (P = 0.047) but not with the slaughter table (P = 0.98) and effluent water from the abattoir house (P = 0.39). These data suggest that the abattoir type may not be as important in the prevalence and spread of STEC as the hygiene practices of the workers. Sequence analysis of a representative isolate showed 100% coverage and 96.46% percentage identity with Escherichia coli O113:H21 (GenBank Accession number: CP031892.1) strain from Canada. This sequence was subsequently submitted to GenBank with accession number MW463885. From evolutionary analyses, the strain from Nigeria, sequenced in this study, is evolutionarily distant when compared with the publicly available sequences from Nigeria. Although no case of E. coli O157 was found within the study area, percent occurrence of non-O157 STEC as high as 46.3% at some of the sampled sites is worrisome and requires regulatory interventions in ensuring hygienic practices at the abattoirs within the study area.


Assuntos
Matadouros , Contaminação de Alimentos , Microbiologia de Alimentos , Carne/microbiologia , Escherichia coli Shiga Toxigênica/genética , Microbiologia Ambiental , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Genoma Bacteriano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Nigéria/epidemiologia , Vigilância em Saúde Pública , Escherichia coli Shiga Toxigênica/classificação
19.
Nat Commun ; 12(1): 3503, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108477

RESUMO

Microbial sulfur metabolism contributes to biogeochemical cycling on global scales. Sulfur metabolizing microbes are infected by phages that can encode auxiliary metabolic genes (AMGs) to alter sulfur metabolism within host cells but remain poorly characterized. Here we identified 191 phages derived from twelve environments that encoded 227 AMGs for oxidation of sulfur and thiosulfate (dsrA, dsrC/tusE, soxC, soxD and soxYZ). Evidence for retention of AMGs during niche-differentiation of diverse phage populations provided evidence that auxiliary metabolism imparts measurable fitness benefits to phages with ramifications for ecosystem biogeochemistry. Gene abundance and expression profiles of AMGs suggested significant contributions by phages to sulfur and thiosulfate oxidation in freshwater lakes and oceans, and a sensitive response to changing sulfur concentrations in hydrothermal environments. Overall, our study provides fundamental insights on the distribution, diversity, and ecology of phage auxiliary metabolism associated with sulfur and reinforces the necessity of incorporating viral contributions into biogeochemical configurations.


Assuntos
Bacteriófagos/metabolismo , Ecossistema , Enxofre/metabolismo , Motivos de Aminoácidos , Bacteriófagos/classificação , Bacteriófagos/genética , Caudovirales/classificação , Caudovirales/genética , Caudovirales/metabolismo , Metabolismo Energético , Microbiologia Ambiental , Genes Virais/genética , Variação Genética , Genoma Viral/genética , Metagenômica , Oxirredução , Filogenia , Domínios Proteicos , Tiossulfatos/metabolismo , Proteínas Virais/química , Proteínas Virais/genética
20.
FEMS Microbiol Ecol ; 97(8)2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34160589

RESUMO

The 'principle of microbial infallibility' was a mainstay of microbial physiology and environmental microbiology in earlier decades. This principle asserts that wherever there is an energetic gain to be made from environmental resources, microorganisms will find a way to take advantage of the situation. Although previously disputed, this claim was revived with the discovery of anammox bacteria and other major contributors to biogeochemistry. Here, we discuss the historical background to microbial infallibility, and focus on its contemporary relevance to metagenomics. Our analysis distinguishes exploration-driven metagenomics from hypothesis-driven metagenomics. In particular, we show how hypothesis-driven metagenomics can use background assumptions of microbial infallibility to enable the formulation of hypotheses to be tested by enrichment cultures. Discoveries of comammox and the anaerobic oxidation of methane are major instances of such strategies, and we supplement them with outlines of additional examples. This overview highlights one way in which metagenomics is making the transition from an exploratory data-analysis programme of research to a hypothesis-testing one. We conclude with a discussion of how microbial infallibility is a heuristic with far-reaching implications for the investigation of life.


Assuntos
Bactérias , Metagenômica , Bactérias/genética , Crescimento Quimioautotrófico , Microbiologia Ambiental , Metano
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