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1.
Int J Med Microbiol ; 314: 151610, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38310676

RESUMO

Shiga toxin-producing E. coli (STEC), including the subgroup of enterohemorrhagic E. coli (EHEC), are important bacterial pathogens which cause diarrhea and the severe clinical manifestation hemolytic uremic syndrome (HUS). Genomic surveillance of STEC/EHEC is a state-of-the-art tool to identify infection clusters and to extract markers of circulating clinical strains, such as their virulence and resistance profile for risk assessment and implementation of infection prevention measures. The aim of the study was characterization of the clinical STEC population in Germany for establishment of a reference data set. To that end, from 2020 to 2022 1257 STEC isolates, including 39 of known HUS association, were analyzed and lead to a classification of 30.4 % into 129 infection clusters. Major serogroups in all clinical STEC analyzed were O26, O146, O91, O157, O103, and O145; and in HUS-associated strains were O26, O145, O157, O111, and O80. stx1 was less frequently and stx2 or a combination of stx, eaeA and ehxA were more frequently found in HUS-associated strains. Predominant stx gene subtypes in all STEC strains were stx1a (24 %) and stx2a (21 %) and in HUS-associated strains were mainly stx2a (69 %) and the combination of stx1a and stx2a (12.8 %). Furthermore, two novel O-antigen gene clusters (RKI6 and RKI7) and strains of serovars O45:H2 and O80:H2 showing multidrug resistance were detected. In conclusion, the implemented surveillance tools now allow to comprehensively define the population of clinical STEC strains including those associated with the severe disease manifestation HUS reaching a new surveillance level in Germany.


Assuntos
Escherichia coli Êntero-Hemorrágica , Infecções por Escherichia coli , Proteínas de Escherichia coli , Síndrome Hemolítico-Urêmica , Escherichia coli Shiga Toxigênica , Humanos , Virulência/genética , Antígenos O/genética , Proteínas de Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Genômica , Alemanha/epidemiologia , Síndrome Hemolítico-Urêmica/epidemiologia , Síndrome Hemolítico-Urêmica/microbiologia , Família Multigênica
2.
Int J Med Microbiol ; 316: 151628, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38936338

RESUMO

Enteroaggregative Escherichia coli (EAEC) strains including those of serogroup O111 are important causes of diarrhea in children. In the Czech Republic, no information is available on the etiological role of EAEC in pediatric diarrhea due to the lack of their targeted surveillance. To fill this gap, we determined the proportion of EAEC among E. coli O111 isolates from children with gastrointestinal disorders ≤ 2 years of age submitted to the National Reference Laboratory for E. coli and Shigella during 2013-2022. EAEC accounted for 177 of 384 (46.1 %) E. coli O111 isolates, being the second most frequent E. coli O111 pathotype. Most of them (75.7 %) were typical EAEC that carried aggR, usually with aaiC and aatA marker genes; the remaining 24.3 % were atypical EAEC that lacked aggR but carried aaiC and/or aatA. Whole genome sequencing of 11 typical and two atypical EAEC O111 strains demonstrated differences in serotypes, sequence types (ST), virulence gene profiles, and the core genomes between these two groups. Typical EAEC O111:H21/ST40 strains resembled by their virulence profiles including the presence of the aggregative adherence fimbriae V (AAF/V)-encoding cluster to such strains from other countries and clustered with them in the core genome multilocus sequence typing (cgMLST). Atypical EAEC O111:H12/ST10 strains lacked virulence genes of typical EAEC and differed from them in cgMLST. All tested EAEC O111 strains displayed stacked-brick aggregative adherence to human intestinal epithelial cells. The AAF/V-encoding cluster was located on a plasmid of 95,749 bp or 93,286 bp (pAAO111) which also carried aggR, aap, aar, sepA, and aat cluster. EAEC O111 strains were resistant to antibiotics, in particular to aminopenicillins and cephalosporins; 88.3 % produced AmpC ß-lactamase, and 4.1 % extended spectrum ß-lactamase. We conclude that EAEC are frequent among E. coli O111 strains isolated from children with gastrointestinal disorders in the Czech Republic. To reliably assess the etiological role of EAEC in pediatric diarrhea, a serotype-independent, PCR-based pathotype surveillance system needs to be implemented in the future.


Assuntos
Diarreia , Infecções por Escherichia coli , Escherichia coli , Sequenciamento Completo do Genoma , Humanos , República Tcheca/epidemiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/epidemiologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Escherichia coli/classificação , Lactente , Diarreia/microbiologia , Fatores de Virulência/genética , Sorogrupo , Proteínas de Escherichia coli/genética , Gastroenteropatias/microbiologia , Antibacterianos/farmacologia , Pré-Escolar , Genoma Bacteriano , Masculino , Feminino , Recém-Nascido , Tipagem de Sequências Multilocus , Transativadores
3.
Z Gastroenterol ; 62(9): 1574-1643, 2024 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-39250962

RESUMO

The aim of the interdisciplinary S2k guideline "Acute infectious gastroenteritis in infants, children and adolescents" is to summarise the current state of knowledge on the clinical presentation, diagnosis, treatment, prevention and hygiene of acute infectious gastroenteritis, including nosocomial gastrointestinal infections, in infants, children and adolescents on the basis of scientific evidence, to evaluate it by expert consensus and to derive practice-relevant recommendations from it. The guideline provides a corridor for action for frequent decisions. It also serves the purpose of evidence-based further education and training and is thus intended to improve the medical care of children with acute gastroenteritis. In particular, the guideline aims to avoid unnecessary hospitalisation of children with AGE and to take preventive measures to avoid and spread infection.


Assuntos
Gastroenterite , Humanos , Criança , Adolescente , Lactente , Pré-Escolar , Gastroenterite/terapia , Gastroenterite/diagnóstico , Gastroenterite/prevenção & controle , Doença Aguda , Recém-Nascido , Alemanha , Gastroenterologia/normas , Medicina Baseada em Evidências , Guias de Prática Clínica como Assunto , Masculino , Feminino , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/diagnóstico
4.
BMC Biol ; 21(1): 76, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37038177

RESUMO

BACKGROUND: Escherichia coli is an opportunistic pathogen which colonizes various host species. However, to what extent genetic lineages of E. coli are adapted or restricted to specific hosts and the genomic determinants of such adaptation or restriction is poorly understood. RESULTS: We randomly sampled E. coli isolates from four countries (Germany, UK, Spain, and Vietnam), obtained from five host species (human, pig, cattle, chicken, and wild boar) over 16 years, from both healthy and diseased hosts, to construct a collection of 1198 whole-genome sequenced E. coli isolates. We identified associations between specific E. coli lineages and the host from which they were isolated. A genome-wide association study (GWAS) identified several E. coli genes that were associated with human, cattle, or chicken hosts, whereas no genes associated with the pig host could be found. In silico characterization of nine contiguous genes (collectively designated as nan-9) associated with the human host indicated that these genes are involved in the metabolism of sialic acids (Sia). In contrast, the previously described sialic acid regulon known as sialoregulon (i.e. nanRATEK-yhcH, nanXY, and nanCMS) was not associated with any host species. In vitro growth experiments with a Δnan-9 E. coli mutant strain, using the sialic acids 5-N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc) as sole carbon source, showed impaired growth behaviour compared to the wild-type. CONCLUSIONS: This study provides an extensive analysis of genetic determinants which may contribute to host specificity in E. coli. Our findings should inform risk analysis and epidemiological monitoring of (antimicrobial resistant) E. coli.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Animais , Bovinos , Humanos , Suínos , Escherichia coli/genética , Estudo de Associação Genômica Ampla , Infecções por Escherichia coli/veterinária , Genômica , Ácidos Siálicos/metabolismo
5.
Artigo em Alemão | MEDLINE | ID: mdl-36525034

RESUMO

INTRODUCTION: In order to improve patient care and to increase food safety within the framework of One Health, the project "Integrated Genomic Surveillance of Zoonotic Agents (IGS-Zoo)" aims to develop concepts for a genomic surveillance of Shiga toxin(Stx)-producing and enterohemorrhagic Escherichia coli (STEC/EHEC) in Germany. METHODS: An online survey was conducted to assess the currently available and applied STEC/EHEC typing methods in the federal laboratories of veterinary regulation, food control, and public health service. RESULTS: Twenty-six questionnaires from 33 participants were evaluated with regard to STEC/EHEC. The number of STEC/EHEC-suspected samples that the laboratories process per year ranges between 10 and 3500, and out of these they obtain between 3 and 1000 pathogenic isolates. Currently the most frequently used typing method is the determination of Stx- and intimin-coding genes using polymerase chain reaction (PCR). Whole genome sequencing (WGS) is currently used by eight federal state laboratories, and nine are planning to implement it in the future. The most common obstacle for further typing of STEC/EHEC is that isolation from sample material is often unsuccessful despite apparent PCR detection of the stx genes. DISCUSSION: The results of the survey should facilitate the integration of the analysis methods developed in the project and emphasize the target groups' individual needs for corresponding training concepts.


Assuntos
Escherichia coli Êntero-Hemorrágica , Infecções por Escherichia coli , Escherichia coli Shiga Toxigênica , Humanos , Toxina Shiga/genética , Alemanha , Escherichia coli Shiga Toxigênica/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária
6.
Artigo em Alemão | MEDLINE | ID: mdl-36547697

RESUMO

BACKGROUND: In recent years, whole genome sequencing (WGS) in combination with bioinformatic analyses has become state of the art in evaluating the pathogenicity/resistance potential and relatedness of bacteria. WGS analysis thus represents a central tool in the investigation of the resistance and virulence potential of pathogens, as well as their dissemination via outbreak clusters and transmission chains within the framework of molecular epidemiology. In order to gain an overview of the available genotypic and phenotypic methods used for pathogen typing of Salmonella and Shiga toxin-producing and enterohemorrhagic Escherichia coli (STEC/EHEC) in Germany at state and federal level, along with the availability of WGS-based typing and corresponding analytical methods, a survey of laboratories was conducted. METHODS: An electronic survey of laboratories working for public health protection and consumer health protection was conducted from February to June 2020. RESULTS AND CONCLUSION: The results of the survey showed that many of the participating laboratories provide a wide range of phenotypic and molecular methods. Molecular typing is most commonly used for species identification of Salmonella. In many cases, WGS-based methods have already been established at federal and state institutions or are in the process of being established. The Illumina sequencing technology is the most widely used technology. The survey confirms the importance of molecular biology and whole genome typing technologies for laboratories in the diagnosis of bacterial zoonotic pathogens.


Assuntos
Infecções por Escherichia coli , Salmonella enterica , Humanos , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Salmonella enterica/genética , Alemanha , Sequenciamento Completo do Genoma/métodos , Epidemiologia Molecular
7.
Emerg Infect Dis ; 28(9): 1890-1894, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35997633

RESUMO

We describe the recent detection of 3 Shiga toxin-producing enteroaggregative Escherichia coli O104:H4 isolates from patients and 1 from pork in the Netherlands that were genetically highly similar to isolates from the 2011 large-scale outbreak in Europe. Our findings stress the importance of safeguarding food supply production chains to prevent future outbreaks.


Assuntos
Infecções por Escherichia coli , Escherichia coli O104 , Escherichia coli Shiga Toxigênica , Surtos de Doenças , Infecções por Escherichia coli/epidemiologia , Alemanha/epidemiologia , Humanos , Toxina Shiga , Escherichia coli Shiga Toxigênica/genética
8.
J Clin Microbiol ; 57(10)2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31366691

RESUMO

Shiga toxin-producing Escherichia coli (STEC) and the STEC subgroup enterohemorrhagic E. coli cause intestinal infections with symptoms ranging from watery diarrhea to hemolytic-uremic syndrome (HUS). A key tool for the epidemiological differentiation of STEC is serotyping. The serotype in combination with the main virulence determinants gives important insight into the virulence potential of a strain. However, a large fraction of STEC strains found in human disease, including strains causing HUS, belongs to less frequently detected STEC serovars or their O/H antigens are unknown or even untypeable. Recent implementation of whole-genome sequence (WGS) analysis, in principle, allows the deduction of serovar and virulence gene information. Therefore, here we compared classical serovar and PCR-based virulence marker detection with WGS-based methods for 232 STEC strains, focusing on less frequently detected STEC serovars and nontypeable strains. We found that the results of WGS-based extraction showed a very high degree of overlap with those of the more classical methods. Specifically, the rate of concordance was 97% for O antigens (OAGs) and 99% for H antigens (HAGs) of typeable strains and >99% for stx1, stx2, or eaeA for all strains. Ninety-eight percent of nontypeable OAGs and 100% of nontypeable HAGs were defined by WGS analysis. In addition, the novel methods enabled a more complete analysis of strains causing severe clinical symptoms and the description of four novel STEC OAG loci. In conclusion, WGS is a promising tool for gaining serovar and virulence gene information, especially from a public health perspective.


Assuntos
Infecções por Escherichia coli/microbiologia , Genótipo , Síndrome Hemolítico-Urêmica/microbiologia , Antígenos O/genética , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética , Sequenciamento Completo do Genoma , Antígenos de Bactérias/genética , Biologia Computacional/métodos , Loci Gênicos , Genoma Bacteriano , Genômica/métodos , Técnicas de Genotipagem , Humanos , Filogenia , Vigilância em Saúde Pública , Sorotipagem , Virulência/genética
9.
PLoS Pathog ; 13(2): e1006159, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28158302

RESUMO

Outer membrane vesicles (OMVs) are important tools in bacterial virulence but their role in the pathogenesis of infections caused by enterohemorrhagic Escherichia coli (EHEC) O157, the leading cause of life-threatening hemolytic uremic syndrome, is poorly understood. Using proteomics, electron and confocal laser scanning microscopy, immunoblotting, and bioassays, we investigated OMVs secreted by EHEC O157 clinical isolates for virulence factors cargoes, interactions with pathogenetically relevant human cells, and mechanisms of cell injury. We demonstrate that O157 OMVs carry a cocktail of key virulence factors of EHEC O157 including Shiga toxin 2a (Stx2a), cytolethal distending toxin V (CdtV), EHEC hemolysin, and flagellin. The toxins are internalized by cells via dynamin-dependent endocytosis of OMVs and differentially separate from vesicles during intracellular trafficking. Stx2a and CdtV-B, the DNase-like CdtV subunit, separate from OMVs in early endosomes. Stx2a is trafficked, in association with its receptor globotriaosylceramide within detergent-resistant membranes, to the Golgi complex and the endoplasmic reticulum from where the catalytic Stx2a A1 fragment is translocated to the cytosol. CdtV-B is, after its retrograde transport to the endoplasmic reticulum, translocated to the nucleus to reach DNA. CdtV-A and CdtV-C subunits remain OMV-associated and are sorted with OMVs to lysosomes. EHEC hemolysin separates from OMVs in lysosomes and targets mitochondria. The OMV-delivered CdtV-B causes cellular DNA damage, which activates DNA damage responses leading to G2 cell cycle arrest. The arrested cells ultimately die of apoptosis induced by Stx2a and CdtV via caspase-9 activation. By demonstrating that naturally secreted EHEC O157 OMVs carry and deliver into cells a cocktail of biologically active virulence factors, thereby causing cell death, and by performing first comprehensive analysis of intracellular trafficking of OMVs and OMV-delivered virulence factors, we provide new insights into the pathogenesis of EHEC O157 infections. Our data have implications for considering O157 OMVs as vaccine candidates.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Infecções por Escherichia coli/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Fatores de Virulência/metabolismo , Virulência/fisiologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Escherichia coli O157 , Humanos , Immunoblotting , Microscopia Eletrônica de Transmissão , Transporte Proteico/fisiologia , Vesículas Transportadoras/fisiologia
10.
BMC Genomics ; 19(1): 647, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30170539

RESUMO

BACKGROUND: Enterohemorrhagic Escherichia coli (EHEC) O26:H11/H-, the most common non-O157 serotype causing hemolytic uremic syndrome worldwide, are evolutionarily highly dynamic with new pathogenic clones emerging rapidly. Here, we investigated the population structure of EHEC O26 isolated from patients in several European countries using whole genome sequencing, with emphasis on a detailed analysis of strains of the highly virulent new European clone (nEC) which has spread since 1990s. RESULTS: Genome-wide single nucleotide polymorphism (SNP)-based analysis of 32 EHEC O26 isolated in the Czech Republic, Germany, Austria and Italy demonstrated a split of the nEC (ST29C2 clonal group) into two distinct lineages, which we termed, based on their temporal emergence, as "early" nEC and "late" nEC. The evolutionary divergence of the early nEC and late nEC is marked by the presence of 59 and 70 lineage-specific SNPs (synapomorphic mutations) in the genomes of the respective lineages. In silico analyses of publicly available E. coli O26 genomic sequences identified the late nEC lineage worldwide. Using a PCR designed to target the late nEC synapomorphic mutation in the sen/ent gene, we identified the early nEC decline accompanied by the late nEC rise in Germany and the Czech Republic since 2004 and 2013, respectively. Most of the late nEC strains harbor one of two major types of Shiga toxin 2a (Stx2a)-encoding prophages. The type I stx2a-phage is virtually identical to stx2a-phage of EHEC O104:H4 outbreak strain, whereas the type II stx2a-phage is a hybrid of EHEC O104:H4 and EHEC O157:H7 stx2a-phages and carries a novel mutation in Stx2a. Strains harboring these two phage types do not differ by the amounts and biological activities of Stx2a produced. CONCLUSIONS: Using SNP-level analyses, we provide the evidence of the evolutionary split of EHEC O26:H11/H- nEC into two distinct lineages, and a recent replacement of the early nEC by the late nEC in Germany and the Czech Republic. PCR targeting the late nEC synapomorphic mutation in ent/sen enables the discrimination of early nEC strains and late nEC strains in clinical and environmental samples, thereby facilitating further investigations of their geographic distribution, prevalence, clinical significance and epidemiology.


Assuntos
Evolução Biológica , Escherichia coli Êntero-Hemorrágica/classificação , Infecções por Escherichia coli/epidemiologia , Variação Genética , Genoma Bacteriano , Sequenciamento Completo do Genoma , DNA Bacteriano , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/microbiologia , Genômica , Humanos , Epidemiologia Molecular , Filogenia
11.
Int J Med Microbiol ; 308(8): 1085-1095, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30115547

RESUMO

Enterohemorrhagic Escherichia coli (EHEC) are a cause of bloody diarrhea, hemorrhagic colitis (HC) and the potentially fatal hemolytic uremic syndrome (HUS). While O157:H7 is the dominant EHEC serotype, non-O157 EHEC have emerged as serious causes of disease. In Germany, the most important non-O157 O-serogroups causing one third of EHEC infections, including diarrhea as well as HUS, are O26, O103, O111 and O145. Interestingly, we identified EHEC O-serogroups O26 and O111 in one single sequence type complex, STC29, that also harbours atypical enteropathogenic E. coli (aEPEC). aEPEC differ from typical EHEC merely in the absence of stx-genes. These findings inspired us to unravel a putative microevolutionary scenario of these non-O157 EHEC by whole genome analyses. Analysis of single nucleotide polymorphisms (SNPs) of the maximum common genome (MCG) of 20 aEPEC (11 human/ 9 bovine) and 79 EHEC (42 human/ 36 bovine/ 1 food source) of STC29 identified three distinct clusters: Cluster 1 harboured strains of O-serogroup O111, the central Cluster 2 harboured only O26 aEPEC strains, while the more heterogeneous Cluster 3 contained both EHEC and aEPEC strains of O-serogroup O26. Further combined analyses of accessory virulence associated genes (VAGs) and insertion sites for mobile genetic elements suggested a parallel evolution of the MCG and the acquisition of virulence genes. The resulting microevolutionary model suggests the development of two distinct EHEC lineages from one common aEPEC ancestor of ST29 by lysogenic conversion with stx-converting bacteriophages, independent of the host species the strains had been isolated from. In conclusion, our cumulative data indicate that EHEC of O-serogroups O26 and O111 of STC29 originate from a common aEPEC ancestor and are bona fide zoonotic agents. The role of aEPEC in the emergence of O26 and O111 EHEC should be considered for infection control measures to prevent possible lysogenic conversion with stx-converting bacteriophages as major vehicle driving the emergence of EHEC lineages with direct Public Health consequences.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli O157/genética , Evolução Molecular , Síndrome Hemolítico-Urêmica/microbiologia , Sorogrupo , Animais , Bovinos , Infecções por Escherichia coli/epidemiologia , Escherichia coli O157/patogenicidade , Genoma Bacteriano/genética , Alemanha/epidemiologia , Síndrome Hemolítico-Urêmica/epidemiologia , Humanos , Polimorfismo de Nucleotídeo Único , Virulência/genética , Sequenciamento Completo do Genoma , Zoonoses/epidemiologia , Zoonoses/microbiologia
12.
Int J Med Microbiol ; 308(5): 539-544, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29884330

RESUMO

Following a school ski-trip to Austria from 10 to 18/02/2017, nine of 25 participants of the group from Lower Saxony (Germany) developed gastroenteritis. The students and teachers (17-41 years) shared meals in a hotel. Active case finding revealed further cases among German school groups from North Rhine-Westphalia and Schleswig-Holstein, staying at the same hotel in February 2017. We conducted two retrospective cohort studies using self-administered questionnaires on clinical symptoms and food consumption. We defined a case as a trip participant in February 2017, staying at the aforementioned hotel and developing diarrhoea, vomiting or abdominal pain during or within ten days after the trip and/or who had a stool sample tested positive for STEC within four weeks after the trip. During the outbreak investigation, Austrian authorities detected that unlabeled raw cow milk delivered by a dairy farm had been offered at the hotel for breakfast during January and February 2017. Stool samples of participants, samples of milk served in the hotel and fecal samples of various animals kept at the milk-delivering farm were examined by culture and polymerase chain reaction. STEC isolates were typed using Pulsed-field Gel Electrophoresis (PFGE) and Whole-Genome Sequencing (WGS). All 25 participants from Lower Saxony completed the questionnaire on symptoms and milk consumption; 14 were cases (56%). Thirteen of 20 participants who had consumed cold milk fell ill (risk ratio (RR): 3.25; 95%-confidence interval (CI): 0.55-19.32). Of 159 trip participants from North Rhine-Westphalia, 81 completed the questionnaire (51%), 25 were cases (31%); RR for cold milk was 2.11 (CI: 0.89-5.03). The combined RR for cold milk in both groups was 2.49 (CI: 1.16-5.35). Shiga toxin 1a-gene and eaeA-gene positive STEC O103:H2 were detected in nine of 32 patients' stool samples and in two of 18 dairy farm cattle. Nine isolates from human stool samples and two isolates from cattle fecal samples yielded the same strain with an almost identical PFGE-pattern and WGS-profile. Microbiological and epidemiological evidence identified raw cow milk as the vehicle. Results may have been compromised by misclassification of cases due to a recall bias and mild symptoms. As a result of this outbreak investigation, the Austrian authorities enforced Austrian law in the hotel, to provide milk only when pasteurized. We recommend re-emphasizing the risk of raw milk consumption to providers.


Assuntos
Infecções por Escherichia coli/transmissão , Gastroenterite/microbiologia , Leite/microbiologia , Alimentos Crus/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Adolescente , Adulto , Animais , Áustria , Bovinos , Surtos de Doenças , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/microbiologia , Microbiologia de Alimentos , Gastroenterite/diagnóstico , Alemanha , Humanos , Pasteurização , Estudos Retrospectivos , Toxina Shiga/genética , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/patogenicidade , Inquéritos e Questionários , Adulto Jovem
13.
Int J Med Microbiol ; 308(7): 890-898, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29937391

RESUMO

Bacteriophages play an important role in the evolution of bacterial pathogens. A phage-mediated transfer of stx-genes to atypical enteropathogenic E. coli (aEPEC) which are prevalent in different hosts, would convert them to enterohemorrhagic E. coli (EHEC). We decided to confirm this hypothesis experimentally to provide conclusive evidence that aEPEC isolated from different mammalian hosts are indeed progenitors of typical EHEC which gain the ability to produce Shiga-Toxin by lysogeny with stx-converting bacteriophages, utilizing the model phage Φ3538 Δstx2::cat. We applied a modified in vitro plaque-assay, using a high titer of a bacteriophage carrying a deletion in the stx2 gene (Φ3538 Δstx2::cat) to increase the detection of lysogenic conversion events. Three wild-type aEPEC strains were chosen as acceptor strains: the murine aEPEC-strain IMT14505 (sequence type (ST)28, serotype Ont:H6), isolated from a striped field mouse (Apodemus agrarius) in the surrounding of a cattle shed, and the human aEPEC-strain 910#00 (ST28, Ont:H6). The close genomic relationship of both strains implies a high zoonotic potential. A third strain, the bovine aEPEC IMT19981, was of serotype O26:H11 and ST21 (STC29). All three aEPEC were successfully lysogenized with phage Φ3538 Δstx2::cat. Integration of the bacteriophage DNA into the aEPEC host genomes was confirmed by amplification of chloramphenicol transferase (cat) marker gene and by Southern-Blot hybridization. Analysis of the whole genome sequence of each of the three lysogens showed that the bacteriophage was integrated into the known tRNA integration site argW, which is highly variable among E. coli. In conclusion, the successful lysogenic conversion of aEPEC with a stx-phage in vitro underlines the important role of aEPEC as progenitors of EHEC. Given the high prevalence and the wide host range of aEPEC acceptors, their high risk of zoonotic transmission should be recognized in infection control measures.


Assuntos
Bacteriófagos/genética , Escherichia coli Enteropatogênica/genética , Escherichia coli Enteropatogênica/patogenicidade , Lisogenia/genética , Toxina Shiga/genética , Animais , Bacteriófagos/crescimento & desenvolvimento , Bovinos , Escherichia coli Enteropatogênica/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Genoma Viral/genética , Humanos , Camundongos
14.
Euro Surveill ; 22(21)2017 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-28597831

RESUMO

We report an ongoing, protracted and geographically dispersed outbreak of haemolytic uraemic syndrome (HUS) and gastroenteritis in Germany, involving 30 cases since December 2016. The outbreak was caused by the sorbitol-fermenting immotile variant of Shiga toxin-producing (STEC) Escherichia coli O157. Molecular typing revealed close relatedness between isolates from 14 cases. One HUS patient died. Results of a case-control study suggest packaged minced meat as the most likely food vehicle. Food safety investigations are ongoing.


Assuntos
Surtos de Doenças , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/epidemiologia , Escherichia coli O157/isolamento & purificação , Gastroenterite/microbiologia , Síndrome Hemolítico-Urêmica/microbiologia , Carne/microbiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Eletroforese em Gel de Campo Pulsado , Escherichia coli O157/genética , Escherichia coli O157/patogenicidade , Feminino , Gastroenterite/complicações , Gastroenterite/epidemiologia , Alemanha/epidemiologia , Síndrome Hemolítico-Urêmica/complicações , Síndrome Hemolítico-Urêmica/epidemiologia , Humanos , Lactente , Recém-Nascido , Sorotipagem , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Escherichia coli Shiga Toxigênica/patogenicidade , Sorbitol , Sequenciamento Completo do Genoma
15.
Euro Surveill ; 22(18)2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-28494842

RESUMO

In 2013, raw pork was the suspected vehicle of a large outbreak (n = 203 cases) of Salmonella Muenchen in the German federal state of Saxony. In 2014, we investigated an outbreak (n = 247 cases) caused by the same serovar affecting Saxony and three further federal states in the eastern part of Germany. Evidence from epidemiological, microbiological and trace-back investigations strongly implicated different raw pork products as outbreak vehicles. Trace-back analysis of S. Muenchen-contaminated raw pork sausages narrowed the possible source down to 54 pig farms, and S. Muenchen was detected in three of them, which traded animals with each other. One of these farms had already been the suspected source of the 2013 outbreak. S. Muenchen isolates from stool of patients in 2013 and 2014 as well as from food and environmental surface swabs of the three pig farms shared indistinguishable pulsed-field gel electrophoresis patterns. Our results indicate a common source of both outbreaks in the primary production of pigs. Current European regulations do not make provisions for Salmonella control measures on pig farms that have been involved in human disease outbreaks. In order to prevent future outbreaks, legislators should consider tightening regulations for Salmonella control in causative primary production settings.


Assuntos
Agricultura , Surtos de Doenças , Fezes/microbiologia , Carne/microbiologia , Infecções por Salmonella/epidemiologia , Salmonella/isolamento & purificação , Sus scrofa , Animais , Eletroforese em Gel de Campo Pulsado , Alemanha/epidemiologia , Humanos , Masculino , Salmonella/classificação , Infecções por Salmonella/diagnóstico
16.
Mol Microbiol ; 98(5): 809-30, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26259566

RESUMO

Thermophilic Campylobacter species colonize the intestine of agricultural and domestic animals commensally but cause severe gastroenteritis in humans. In contrast to other enteropathogenic bacteria, Campylobacter has been considered to be non-glycolytic, a metabolic property originally used for their taxonomic classification. Contrary to this dogma, we demonstrate that several Campylobacter coli strains are able to utilize glucose as a growth substrate. Isotopologue profiling experiments with (13) C-labeled glucose suggested that these strains catabolize glucose via the pentose phosphate and Entner-Doudoroff (ED) pathways and use glucose efficiently for de novo synthesis of amino acids and cell surface carbohydrates. Whole genome sequencing of glycolytic C. coli isolates identified a genomic island located within a ribosomal RNA gene cluster that encodes for all ED pathway enzymes and a glucose permease. We could show in vitro that a non-glycolytic C. coli strain could acquire glycolytic activity through natural transformation with chromosomal DNA of C. coli and C. jejuni subsp. doylei strains possessing the ED pathway encoding plasticity region. These results reveal for the first time the ability of a Campylobacter species to catabolize glucose and provide new insights into how genetic macrodiversity through intra- and interspecies gene transfer expand the metabolic capacity of this food-borne pathogen.


Assuntos
Campylobacter coli/genética , Campylobacter coli/metabolismo , Glucose/metabolismo , Glicólise/genética , Via de Pentose Fosfato/genética , Animais , Infecções por Campylobacter/microbiologia , Campylobacter coli/crescimento & desenvolvimento , Campylobacter jejuni/genética , Campylobacter jejuni/crescimento & desenvolvimento , Campylobacter jejuni/metabolismo , Isótopos de Carbono , Galinhas , DNA Bacteriano/metabolismo , Genoma Bacteriano , Ilhas Genômicas , Humanos , Análise de Sequência de DNA
17.
J Clin Microbiol ; 54(5): 1357-63, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26984976

RESUMO

Alongside the well-characterized enterohemorrhagic Escherichia coli (EHEC) O157:H7, serogroup O157 comprises sorbitol-fermenting typical and atypical enteropathogenic E. coli (EPEC/aEPEC) strains that carry the intimin-encoding gene eae but not Shiga toxin-encoding genes (stx). Since little is known about these pathogens, we characterized 30 clinical isolates from patients with hemolytic uremic syndrome (HUS) or uncomplicated diarrhea with respect to their flagellin gene (fliC) type and multilocus sequence type (MLST). Moreover, we applied whole-genome sequencing (WGS) to determine the phylogenetic relationship with other eae-positive EHEC serotypes and the composition of the rfbO157 region. fliC typing resulted in five fliC types (H7, H16, H34, H39, and H45). Isolates of each fliC type shared a unique ST. In comparison to the 42 HUS-associated E. coli (HUSEC) strains, only the stx-negative isolates with fliCH7 shared their ST with EHEC O157:H7/H(-) strains. With the exception of one O157:H(-) fliCH16 isolate, HUS was exclusively associated with fliCH7. WGS corroborated the separation of the fliCH7 isolates, which were closely related to the EHEC O157:H7/H(-) isolates, and the diverse group of isolates exhibiting different fliC types, indicating independent evolution of the different serotypes. This was also supported by the heterogeneity within the rfbO157 region that exhibited extensive recombinations. The genotypic subtypes and distribution of clinical symptoms suggested that the stx-negative O157 strains with fliCH7 were originally EHEC strains that lost stx The remaining isolates form a distinct and diverse group of atypical EPEC isolates that do not possess the full spectrum of virulence genes, underlining the importance of identifying the H antigen for clinical risk assessment.


Assuntos
Escherichia coli Enteropatogênica/classificação , Escherichia coli Enteropatogênica/metabolismo , Escherichia coli O157/classificação , Escherichia coli O157/metabolismo , Variação Genética , Filogenia , Sorbitol/metabolismo , Diarreia/microbiologia , Escherichia coli Enteropatogênica/genética , Escherichia coli Enteropatogênica/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/genética , Escherichia coli O157/isolamento & purificação , Proteínas de Escherichia coli/genética , Fermentação , Genoma Bacteriano , Síndrome Hemolítico-Urêmica/microbiologia , Humanos , Tipagem Molecular , Análise de Sequência de DNA
18.
Int J Syst Evol Microbiol ; 66(2): 881-888, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26620413

RESUMO

The taxonomic position of five strains isolated from horse faeces, and which shared identical 16S rRNA gene sequences, were studied. Cells of all isolates are Gram-stain-negative, obligately aerobic and have a rod-shaped appearance. The strains show highest 16S rRNA gene sequence similarities to Acinetobacter lwoffii (98.3 %), Acinetobacter haemolyticus (98.0 %), Acienetobacter johnsonii (97.9 %) and Acinetobacter brisouii (97.9 %). Whole-genome sequencing of strain 114T and phylogeny reconstruction based on a core set of 1061 Acinetobacter genes indicated that A. bouvetii CIP 107468T was the closest relative among species of the genus Acinetobacter for which whole genome sequences are available. The genomic DNA G+C content of strain 114T is 34.9 mol%, which is lower than any other value reported for the genus Acinetobacter. The predominant polyamine is 1,3-diaminopropane, which is typical for the genus Acinetobacter. The most abundant fatty acids are C16 : 1ω7c and/or iso-C15 : 0 2-OH (36 %) and C16 : 0 (28 %). The proportion of C18 : 1ω9c (7 %) is distinctively low compared to most species of the genus. The major ubiquinone of strain 114T is Q-9. Microscopic studies revealed the presence of pili and the absence of flagella. The capability of all five strains to utilize l-arabinose and gentisate as well as their lack of growth at temperatures of 41 °C and above provide sufficient criteria to distinguish the isolates from all species of the genus Acinetobacter with validly published names. Based on these combined data, the five isolates represent a novel species of the genus Acinetobacter, for which the name Acinetobacter equi sp. nov. is proposed. The type strain is 114T ( = DSM 27228T = CCUG 65204T).

19.
Int J Med Microbiol ; 305(7): 697-704, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26372529

RESUMO

Infections by intestinal pathogenic Escherichia coli (E. coli) are among those causing a high mortality and morbidity due to diarrheal disease and post infection sequelae worldwide. Since introduction of the Infection Protection Act in Germany 2001, these pathogens rank third among bacterial infections of the gastrointestinal tract. As a major pathovar Shiga toxin-producing E. coli (STEC) which include enterohemorrhagic E. coli (EHEC) play a leading role in occurrence of sporadic cases and disease outbreaks. An outstanding example is the large outbreak in spring 2011 caused by EHEC/EAEC O104:H4. To monitor and trace back STEC infections, national surveillance programs have been implemented including activities of the German National Reference Centre for Salmonella and other Enteric Bacterial Pathogens (NRC). This review highlights advances in our understanding of STEC in the last 20 years of STEC surveillance by the NRC. Here important characteristics of STEC strains from human infections and outbreaks in Germany between 1997 and 2013 are summarized.


Assuntos
Surtos de Doenças , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Monitoramento Epidemiológico , Alemanha/epidemiologia , Política de Saúde , Humanos , Prevalência
20.
Int J Med Microbiol ; 305(3): 404-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25801683

RESUMO

In 2011, the Shiga toxin- and extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli O104:H4 caused a serious outbreak of gastroenteritis in Germany. This strain carried bla(CTX-M-15) and bla(TEM-1) on an IncI1-ST31 plasmid. During screening of individuals at risk for acquisition of the epidemic E. coli O104:H4, we isolated another ESBL-producing and Shiga toxin-positive E. coli belonging to serotype O91:H14 from feces of a human patient. Interestingly, the patient also carried a further ESBL-producing but Shiga toxin-negative E. coli. Both strains harbored bla(CTX-M-15) and bla(TEM-1) on an IncI1-ST31 plasmid, which was indistinguishable regarding size and plasmid restriction pattern from the plasmid of the epidemic E. coli O104:H4 strain. The patient had traveled to India 6 months prior to the isolation of the E. coli strains. This is the first report of an ESBL-producing, Shiga toxin-positive E. coli of serogroup O91. Our data suggest a high propensity of the IncI1-ST31 plasmid to spread in the human and/or animal population.


Assuntos
Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Fezes/microbiologia , Plasmídeos/análise , Escherichia coli Shiga Toxigênica/enzimologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , beta-Lactamases/metabolismo , DNA Bacteriano/genética , Proteínas de Escherichia coli/genética , Transferência Genética Horizontal , Alemanha , Humanos , Índia , Peso Molecular , Mapeamento por Restrição , Sorotipagem , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética , Viagem , beta-Lactamases/genética
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