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1.
Sci Total Environ ; 951: 175475, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39142400

RESUMO

Antimicrobial resistance (AMR) is a major global public threat, now largely reported in natural environments. Seabirds are carriers of extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-E. coli), but different foraging and breeding behaviour could impact ESBL-E. coli circulation. We compared the prevalence and genetic determinants of ESBL-E. coli from resident Kelp gulls (Larus dominicanus, Ld), migratory Franklin's gulls (Larus pipixcan, Lp), and endemic Peruvian pelicans (Pelecanus thagus, Pt) from the Humboldt Current Ecosystem (HCE) of central Chile. From 2020 to 2022, we collected 699 fresh faecal samples (Ld = 449, Lp = 116, Pt = 134), and isolated 271 ESBL-E. coli (39 %). Whole-genome-sequencing (WGS) was performed on 85 E. coli selected isolates to identify their Sequence Type (ST), AMR genes, virulence genes, mobile genetic elements (MGE), and to assess potential interspecies transmission. ESBL-genes were detected in the remaining ESBL-E. coli isolates by PCR. ESBL-E. coli prevalence in Ld (46 % [CI: 42-51 %]) and Pt (34 % [CI: 27-43 %]) was higher than in Lp (15 % [CI: 9-22 %]). WGS revealed 41 ESBL-E. coli STs including pandemic clones ST10, ST58, ST131 and ST410. The blaCTX-M-1 and blaCTX-M-15 genes were the most prevalent among ESBL genes, and were mostly associated with MGE IncI1-I(Alpha) and ISEc9. We also report the pAmpC blaCMY-2 gene associated to MGE Inc1-I(Alpha) and IS640 in two E. coli from a Ld and a Lp. Eight ESBL-E. coli of the same ST were shared by at least two seabird species, including ST10 (Ld and Pt); ST88, ST410 and ST617 (Pt and Lp); ST38, ST58, ST131, and SST1722 (three species). Single nucleotide polymorphism (SNP) phylogenetic analyses of ST38, ST617 and ST1722 showed a low difference of SNPs between STs found in different seabird species, suggesting ESBL-E. coli clonal exchanges. Our results highlight ESBL-E. coli dissemination across seabirds of the HCE, including species that unusually forage on human waste like pelicans.


Assuntos
Infecções por Escherichia coli , Escherichia coli , beta-Lactamases , Escherichia coli/genética , Animais , beta-Lactamases/genética , Chile/epidemiologia , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/microbiologia , Prevalência , Charadriiformes/microbiologia , Aves/microbiologia , Fezes/microbiologia
2.
J Vet Med Sci ; 80(1): 138-146, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-29249728

RESUMO

Escherichia albertii is a recently discovered species with a limited number of well characterized strains. The aim of this study was to characterize four of the E. albertii strains, which were among 41 identified Escherichia strains isolated from the feces of living animals on James Ross Island, Antarctica, and Isla Magdalena, Patagonia. Sequencing of 16S rDNA, automated ribotyping, and rep-PCR were used to identify the four E. albertii isolates. Phylogenetic analyses based on multi-locus sequence typing showed these isolates to be genetically most similar to the members of E. albertii phylogroup G3. These isolates encoded several virulence factors including those, which are characteristic of E. albertii (cytolethal distending toxin and intimin) as well as bacteriocin determinants that typically have a very low prevalence in E. coli strains (D, E7). Moreover, E. albertii protein extracts caused cell cycle arrest in human cell line A375, probably because of cytolethal distending toxin activity.


Assuntos
Escherichia/metabolismo , Animais , Regiões Antárticas , Charadriiformes/microbiologia , Chile , Eletroforese em Gel de Campo Pulsado/veterinária , Escherichia/genética , Escherichia/isolamento & purificação , Fezes/microbiologia , Tipagem de Sequências Multilocus/veterinária , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico 16S/genética , Ribotipagem/veterinária , Focas Verdadeiras/microbiologia , Spheniscidae/microbiologia
3.
Appl Environ Microbiol ; 82(20): 6223-6232, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27520817

RESUMO

Salmonella enterica subsp. enterica serotype Enteritidis is a major cause of human salmonellosis worldwide; however, little is known about the genetic relationships between S Enteritidis clinical strains and S Enteritidis strains from other sources in Chile. We compared the whole genomes of 30 S Enteritidis strains isolated from gulls, domestic chicken eggs, and humans in Chile, to investigate their phylogenetic relationships and to establish their relatedness to international strains. Core genome multilocus sequence typing (cgMLST) analysis showed that only 246/4,065 shared loci differed among these Chilean strains, separating them into two clusters (I and II), with cluster II being further divided into five subclusters. One subcluster (subcluster 2) contained strains from all surveyed sources that differed at 1 to 18 loci (of 4,065 loci) with 1 to 18 single-nucleotide polymorphisms (SNPs), suggesting interspecies transmission of S Enteritidis in Chile. Moreover, clusters were formed by strains that were distant geographically, which could imply that gulls might be spreading the pathogen throughout the country. Our cgMLST analysis, using other S Enteritidis genomes available in the National Center for Biotechnology Information (NCBI) database, showed that S Enteritidis strains from Chile and the United States belonged to different lineages, which suggests that S Enteritidis regional markers might exist and could be used for trace-back investigations. IMPORTANCE: This study highlights the importance of gulls in the spread of Salmonella Enteritidis in Chile. We revealed a close genetic relationship between some human and gull S Enteritidis strains (with as few as 2 of 4,065 genes being different), and we also found that gull strains were present in clusters formed by strains isolated from other sources or distant locations. Together with previously published evidence, this suggests that gulls might be spreading this pathogen between different regions in Chile and that some of those strains have been transmitted to humans. Moreover, we discovered that Chilean S Enteritidis strains clustered separately from most of S Enteritidis strains isolated throughout the world (in the GenBank database) and thus it might be possible to distinguish the geographical origins of strains based on specific genomic features. This could be useful for trace-back investigations of foodborne illnesses throughout the world.


Assuntos
Doenças das Aves/microbiologia , Charadriiformes/microbiologia , Genoma Bacteriano , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Infecções por Salmonella/microbiologia , Salmonella enteritidis/genética , Animais , Doenças das Aves/transmissão , Chile , Humanos , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/transmissão , Infecções por Salmonella/transmissão , Salmonelose Animal/transmissão , Salmonella enteritidis/isolamento & purificação , Sorogrupo
4.
Antimicrob Agents Chemother ; 60(11): 6924-6927, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27572403

RESUMO

Extended-spectrum-cephalosporin-resistant Enterobacteriaceae are a public health concern due to limited treatment options. Here, we report on the occurrence and the molecular characteristics of extended-spectrum-cephalosporin-resistant Enterobacteriaceae recovered from wild birds (kelp gulls). Our results revealed kelp gulls as a reservoir of various extended-spectrum cephalosporinase genes associated with different genetic platforms. In addition, we report for the first time the presence of a known epidemic clone of Salmonella enterica serotype Heidelberg (JF6X01.0326/XbaI.1966) among wild birds.


Assuntos
Resistência às Cefalosporinas/genética , Charadriiformes/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Animais , Antibacterianos/farmacologia , Resistência às Cefalosporinas/efeitos dos fármacos , Cefalosporinase/genética , Cefalosporinas/farmacologia , Enterobacteriaceae/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Plasmídeos/genética , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , América do Sul
5.
PLoS One ; 10(10): e0141315, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26496629

RESUMO

Migratory birds have been suggested to contribute to long-distance dispersal of antimicrobial resistant bacteria, but tests of this hypothesis are lacking. In this study we determined resistance profiles and genotypes of ESBL-producing bacteria in randomly selected Escherichia coli from Franklin´s gulls (Leucophaeus pipixcan) at breeding sites in Canada and compared with similar data from the gulls' wintering grounds in Chile. Resistant E. coli phenotypes were common, most notably to ampicillin (30.1%) and cefadroxil (15.1%). Furthermore, 17.0% of the gulls in Canada carried ESBL producing bacteria, which is higher than reported from human datasets from the same country. However, compared to gulls sampled in Chile (30.1%) the prevalence of ESBL was much lower. The dominant ESBL variants in Canada were blaCTX-M-14 and blaCTX-M-15 and differed in proportions to the data from Chile. We hypothesize that the observed differences in ESBL variants are more likely linked to recent exposure to bacteria from anthropogenic sources, suggesting high local dissemination of resistant bacteria both at breeding and non-breeding times rather than a significant trans-hemispheric exchange through migrating birds.


Assuntos
Charadriiformes/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/enzimologia , Resistência beta-Lactâmica/genética , beta-Lactamases/genética , Migração Animal , Animais , Canadá , Chile , Vetores de Doenças , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Genótipo
6.
Microb Drug Resist ; 21(1): 111-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25313843

RESUMO

The role of wild animals, particularly migratory birds, in the dissemination of antibiotic-resistant bacteria between geographically distant ecosystems is usually underestimated. The aim of this work was to characterize the Escherichia coli population from Franklin's gull feces, focusing on the extended-spectrum ß-lactamase (ESBL)-producing strains. In the summer of 2011, 124 fecal swabs from seagulls (1 of each) migrating from the United States and Canada to the coast of Antofagasta, north of Chile, were collected. Samples were seeded on MacConkey agar supplemented with 2 µg/ml of cefotaxime and a single colony from each plate was tested for ESBL production by the double-disk ESBL synergy test. Antibiotic susceptibility was determined by the disk diffusion method and blaESBL genes were amplified and sequenced. The genetic diversity of isolates was explored by pulsed-field gel electrophoresis (PFGE)-XbaI and multilocus sequence typing. A total of 91 E. coli isolates with high rates of antibiotic resistance were identified. Carbapenemase production was not detected, whereas 67 of the 91 (54%) isolates exhibited an ESBL phenotype due to the presence of CTX-M-15 (61.3%), CTX-M-2 (19.3%), CTX-M-22 (16.1%), and CTX-M-3 (1.6%) coding genes. High genetic diversity was observed, with 30 PFGE patterns and 23 sequence types (STs), including ST131 (18%), ST44 (15%), ST617 (9%), and ST10 (9%). Results presented here are complementary to those previously reported by Hernández et al. in the same gull species, but located in the Central Region of Chile. Differences observed between gulls from both areas lead us to hypothesize that gulls from the northern location retain, as gut carriers, those resistant bacteria acquired in the United States and/or Canada.


Assuntos
Charadriiformes/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/isolamento & purificação , beta-Lactamases/genética , Migração Animal , Animais , Chile , Eletroforese em Gel de Campo Pulsado , Escherichia coli/enzimologia , Escherichia coli/genética , Fezes/microbiologia , Genes Bacterianos , Variação Genética , Intestinos/microbiologia , Tipagem de Sequências Multilocus , América do Norte , Resistência beta-Lactâmica
7.
Epidemiol Infect ; 143(6): 1187-93, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25148565

RESUMO

Patagonia in southern South America is among the few world regions where direct human impact is still limited but progressively increasing, mainly represented by tourism, farming, fishing and mining activities. The sanitary condition of Patagonian wildlife is unknown, in spite of being critical for the assessment of anthropogenic effects there. The aim of this study was the characterization of Salmonella enterica strains isolated from wild colonies of Magellanic penguins (Spheniscus magellanicus) located in Magdalena Island and Otway Sound, in Chilean Patagonia. Eight isolates of Salmonella were found, belonging to Agona and Enteritidis serotypes, with an infection rate of 0·38%. Resistance to ampicillin, cefotaxime, ceftiofur and tetracycline antimicrobials were detected, and some of these strains showed genotypic similarity with Salmonella strains isolated from humans and gulls, suggesting inter-species transmission cycles and strengthening the role of penguins as sanitary sentinels in the Patagonian ecosystem.


Assuntos
Salmonelose Animal/transmissão , Salmonella enterica , Spheniscidae/microbiologia , Animais , Animais Selvagens/microbiologia , Antibacterianos/farmacologia , Charadriiformes/microbiologia , Chile/epidemiologia , Farmacorresistência Bacteriana , Ecossistema , Humanos , Infecções por Salmonella/transmissão , Salmonelose Animal/epidemiologia , Salmonelose Animal/microbiologia , Salmonella enterica/efeitos dos fármacos
8.
Vector Borne Zoonotic Dis ; 13(12): 884-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24107205

RESUMO

Salmonella enterica is a pathogen with a wide host-range that presents great concern in developed and developing countries. To determine and characterize Salmonella strains found in Chile's waterfowl, we sampled 758 birds along 2000 km of the Chilean coast. In this sample, 46 isolates from 10 serotypes were detected, several with multidrug resistance phenotypes and different combinations of virulence-associated genes (virulotypes). These results suggest that Salmonella infection in waterfowl in Chile could have impacts on public and animal health.


Assuntos
Antibacterianos/farmacologia , Doenças das Aves/microbiologia , Charadriiformes/microbiologia , Farmacorresistência Bacteriana Múltipla , Salmonelose Animal/microbiologia , Salmonella enterica/isolamento & purificação , Animais , Doenças das Aves/epidemiologia , Chile/epidemiologia , Genótipo , Humanos , Fenótipo , Salmonelose Animal/epidemiologia , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/patogenicidade , Sorotipagem/veterinária , Virulência
9.
PLoS One ; 8(9): e76150, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24098774

RESUMO

We investigated the general level of antibiotic resistance with further analysis of extended-spectrum beta-lactamase (ESBL) prevalence, as well as the population structure of E. coli in fecal flora of humans and Franklin's gulls (Leucophaeus pipixcan) in central parts of Chile. We found a surprisingly high carriage rate of ESBL-producing E. coli among the gulls 112/372 (30.1%) as compared to the human population 6/49 (12.2%.) Several of the E. coli sequence types (STs) identified in birds have previously been reported as Multi Drug Resistant (MDR) human pathogens including the ability to produce ESBLs. This means that not only commensal flora is shared between birds and humans but also STs with pathogenic potential. Given the migratory behavior of Franklin's gulls, they and other migratory species, may be a part of ESBL dissemination in the environment and over great geographic distances. Apart from keeping the antibiotic use low, breaking the transmission chains between the environment and humans must be a priority to hinder the dissemination of resistance.


Assuntos
Charadriiformes/microbiologia , Demografia , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , beta-Lactamases/metabolismo , Adulto , Animais , Chile , DNA Girase/genética , Primers do DNA/genética , Fezes/microbiologia , Feminino , Genótipo , Humanos , Masculino , Tipagem de Sequências Multilocus , beta-Lactamases/genética
10.
J Wildl Dis ; 48(4): 1105-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23060519

RESUMO

Polymerase chain reaction confirmed that two gull species in Talcahuano, Chile, shed Salmonella. Fecal samples from resident Larus dominicanus had prevalences of 51.2% for Salmonella spp. and 26.3% for Salmonella Enteritidis. Prevalences in samples from migratory Leucophaeus pipixcan were 75% and 30% respectively. Risks to public health may exist.


Assuntos
Doenças das Aves/epidemiologia , Charadriiformes/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Salmonella/isolamento & purificação , Animais , Portador Sadio/veterinária , Reservatórios de Doenças/microbiologia , Reservatórios de Doenças/veterinária , Fezes/microbiologia , Feminino , Masculino , Reação em Cadeia da Polimerase em Tempo Real/métodos , Especificidade da Espécie
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