Norwegian Sheep Are an Important Reservoir for Human-Pathogenic Escherichia coli O26:H11

ABSTRACTA previous national survey ofEscherichia coliin Norwegian sheep detectedeae-positive (eae+)E. coliO26:H11 isolates in 16.3% (80/491) of the flocks. The purpose of the present study was to evaluate the human-pathogenic potential of these ovine isolates by comparing them withE. coliO26 isolates from humans infected in Norway. All humanE. coliO26 isolates studied carried theeaegene and shared flagellar type H11. Two-thirds of the sheep flocks and 95.1% of the patients harbored isolates containingarcAallele type 2 andespKand were classified as enterohemorrhagicE. coli(EHEC) (stxpositive) or EHEC-like (stxnegative). These isolates were further divided into group A (EspK2 positive), associated withstx2-EDL933andstcEO103, and group B (EspK1 positive), associated withstx1a. Although thestxgenes were more frequently present in isolates from patients (46.3%) than in those from sheep flocks (5%), more than half of the ovine isolates in the EHEC/EHEC-like group had multiple-locus variable number of tandem repeat analysis (MLVA) profiles that were identical to those seen instx-positive human O26:H11 isolates. This indicates that EHEC-like ovine isolates may be able to acquirestx-carrying bacteriophages and thereby have the possibility to cause serious illness in humans. The remaining one-third of the sheep flocks and two of the patients had isolates fulfilling the criteria for atypical enteropathogenicE. coli(aEPEC):arcAallele type 1 andespKnegative (group C). The majority of these ovine isolates showed MLVA profiles not previously seen inE. coliO26:H11 isolates from humans. However, according to their virulence gene profile, the aEPEC ovine isolates should be considered potentially pathogenic for humans. In conclusion, sheep are an important reservoir of human-pathogenicE. coliO26:H11 isolates in Norway.

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Potentially Human-Pathogenic Escherichia coli O26 in Norwegian Sheep Flocks

Applied and Environmental Microbiology ◽

10.1128/aem.00189-11 ◽

2011 ◽

Vol 77 (14) ◽

pp. 4949-4958 ◽

Cited By ~ 21

Author(s):

C. Sekse ◽

M. Sunde ◽

B.-A. Lindstedt ◽

P. Hopp ◽

T. Bruheim ◽

...

Keyword(s):

Escherichia Coli ◽

Variable Number Tandem Repeat ◽

Variable Number ◽

Human Pathogens ◽

Content Type ◽

Representative Sampling ◽

E Coli ◽

Pathogenic Escherichia Coli ◽

Close Relationship ◽

Large Survey

ABSTRACTA national survey ofEscherichia coliO26 in Norwegian sheep flocks was conducted, using fecal samples to determine the prevalence. In total, 491 flocks were tested, andE. coliO26 was detected in 17.9% of the flocks. One hundred forty-twoE. coliO26 isolates were examined for flagellar antigens (H typing) and four virulence genes, includingstxandeae, to identify possible Shiga toxin-producingE. coli(STEC) and enteropathogenicE. coli(EPEC). Most isolates (129 out of 142) were identified asE. coliO26:H11. They possessedeaeand may have potential as human pathogens, although only a small fraction were identified as STEC O26:H11, giving a prevalence in sheep flocks of only 0.8%. Correspondingly, the sheep flock prevalence of atypical EPEC (aEPEC) O26:H11 was surprisingly high (15.9%). The genetic relationship between theE. coliO26:H11 isolates was investigated by pulsed-field gel electrophoresis (PFGE) and multilocus variable number tandem repeat analysis (MLVA), identifying 63 distinct PFGE profiles and 22 MLVA profiles. Although the MLVA protocol was less discriminatory than PFGE and a few cases of disagreement were observed, comparison by partition mapping showed an overall good accordance between the two methods. A close relationship between a few isolates of aEPEC O26:H11 and STEC O26:H11 was identified, but all theE. coliO26:H11 isolates should be considered potentially pathogenic to humans. The present study consisted of a representative sampling of sheep flocks from all parts of Norway. This is the first large survey of sheep flocks focusing onE. coliO26 in general, including results of STEC, aEPEC, and nonpathogenic isolates.

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Characteristics of Emerging Human-Pathogenic Escherichia coli O26:H11 Strains Isolated in France between 2010 and 2013 and Carrying thestx2dGene Only

Journal of Clinical Microbiology ◽

10.1128/jcm.02290-14 ◽

2014 ◽

Vol 53 (2) ◽

pp. 486-492 ◽

Cited By ~ 35

Author(s):

Sabine Delannoy ◽

Patricia Mariani-Kurkdjian ◽

Stephane Bonacorsi ◽

Sandrine Liguori ◽

Patrick Fach

Keyword(s):

Escherichia Coli ◽

Virulence Gene ◽

Gene Profiling ◽

Content Type ◽

E Coli ◽

Negative Results ◽

Pathogenic Escherichia Coli ◽

Short Palindromic Repeat ◽

Uremic Syndrome ◽

First Time

Strains ofEscherichia coliO26:H11 that were positive forstx2alone (n= 23), which were not epidemiologically related or part of an outbreak, were isolated from pediatric patients in France between 2010 and 2013. We were interested in comparing these strains with the new highly virulentstx2a-positiveE. coliO26 clone sequence type 29 (ST29) that has emerged recently in Europe, and we tested them by multilocus sequence typing (MLST),stx2subtyping, clustered regularly interspaced short palindromic repeat (CRISPR) sequencing, and plasmid (ehxA,katP,espP, andetpD) and chromosomal (Z2098,espK, andespV) virulence gene profiling. We showed that 16 of the 23 strains appeared to correspond to this new clone, but the characteristics of 12 strains differed significantly from the previously described characteristics, with negative results for both plasmid and chromosomal genetic markers. These 12 strains exhibited a ST29 genotype and related CRISPR arrays (CRISPR2a alleles 67 or 71), suggesting that they evolved in a common environment. This finding was corroborated by the presence ofstx2din 7 of the 12 ST29 strains. This is the first time thatE. coliO26:H11 carryingstx2dhas been isolated from humans. This is additional evidence of the continuing evolution of virulent Shiga toxin-producingE. coli(STEC) O26 strains. A new O26:H11 CRISPR PCR assay, SP_O26_E, has been developed for detection of these 12 particular ST29 strains ofE. coliO26:H11. This test is useful to better characterize thestx2-positive O26:H11 clinical isolates, which are associated with severe clinical outcomes such as bloody diarrhea and hemolytic uremic syndrome.

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Prevalence and Genomic Characterization of Escherichia coli O157:H7 in Cow-Calf Herds throughout California

Applied and Environmental Microbiology ◽

10.1128/aem.00734-17 ◽

2017 ◽

Vol 83 (16) ◽

Cited By ~ 6

Author(s):

Jay N. Worley ◽

Kristopher A. Flores ◽

Xun Yang ◽

Jennifer A. Chase ◽

Guojie Cao ◽

...

Keyword(s):

Escherichia Coli ◽

Large Scale ◽

Fresh Produce ◽

Bacterial Pathogen ◽

Virulence Gene ◽

The United States ◽

Pathogenic Potential ◽

Content Type ◽

E Coli ◽

Cow Calf

ABSTRACT Escherichia coli serotype O157:H7 is a zoonotic food- and waterborne bacterial pathogen that causes a high hospitalization rate and can cause life-threatening complications. Increasingly, E. coli O157:H7 infections appear to originate from fresh produce. Ruminants, such as cattle, are a prominent reservoir of E. coli O157:H7 in the United States. California is one of the most agriculturally productive regions in the world for fresh produce, beef, and milk. The close proximity of fresh produce and cattle presents food safety challenges on a uniquely large scale. We performed a survey of E. coli O157:H7 on 20 farms in California to observe the regional diversity and prevalence of E. coli O157:H7. Isolates were obtained from enrichment cultures of cow feces. Some farms were sampled on two dates. Genomes from isolates were sequenced to determine their relatedness and pathogenic potential. E. coli O157:H7 was isolated from approximately half of the farms. The point prevalence of E. coli O157:H7 on farms was highly variable, ranging from zero to nearly 90%. Within farms, generally one or a few lineages were found, even when the rate of isolation was high. On farms with high isolation rates, a single clonal lineage accounted for most of the isolates. Farms that were visited months after the first visit might have had the same lineages of E. coli O157:H7. Strains of E. coli O157:H7 may be persistent for months on farms. IMPORTANCE This survey of 20 cow-calf operations from different regions of California provides an in depth look at resident Escherichia coli O157:H7 populations at the molecular level. E. coli O157:H7 is found to have a highly variable prevalence, and with whole-genome sequencing, high prevalences in herds were found to be due to a single lineage shed from multiple cows. Few repeat lineages were found between farms in this area; therefore, we predict that E. coli O157:H7 has significant diversity in this area beyond what is detected in this survey. All isolates from this study were found to have pathogenic potential based on the presence of key virulence gene sequences. This represents a novel insight into pathogen diversity within a single subtype and will inform future attempts to survey regional pathogen populations.

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Phylogenetic and Molecular Analysis of Food-Borne Shiga Toxin-Producing Escherichia coli

Applied and Environmental Microbiology ◽

10.1128/aem.03552-12 ◽

2013 ◽

Vol 79 (8) ◽

pp. 2731-2740 ◽

Cited By ~ 27

Author(s):

Elisabeth Hauser ◽

Alexander Mellmann ◽

Torsten Semmler ◽

Helen Stoeber ◽

Lothar H. Wieler ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Virulence Gene ◽

Human Infection ◽

Pathogenic Potential ◽

Content Type ◽

E Coli ◽

Food Borne ◽

Strain Collection ◽

Integration Sites

ABSTRACTSeventy-five food-associated Shiga toxin-producingEscherichia coli(STEC) strains were analyzed by molecular and phylogenetic methods to describe their pathogenic potential. The presence of the locus of proteolysis activity (LPA), the chromosomal pathogenicity island (PAI) PAI ICL3, and the autotransporter-encoding genesabAwas examined by PCR. Furthermore, the occupation of the chromosomal integration sites of the locus of enterocyte effacement (LEE),selC,pheU, andpheV, as well as the Stx phage integration sitesyehV,yecE,wrbA,z2577, andssrA, was analyzed. Moreover, the antibiotic resistance phenotypes of all STEC strains were determined. Multilocus sequence typing (MLST) was performed, and sequence types (STs) and sequence type complexes (STCs) were compared with those of 42 hemolytic-uremic syndrome (HUS)-associated enterohemorrhagicE. coli(HUSEC) strains. Besides 59 STs and 4 STCs, three larger clusters were defined in this strain collection. Clusters A and C consist mostly of highly pathogeniceae-positive HUSEC strains and some related food-borne STEC strains. A member of a new O26 HUS-associated clone and the 2011 outbreak strainE. coliO104:H4 were found in cluster A. Cluster B comprises onlyeae-negative food-borne STEC strains as well as mainlyeae-negative HUSEC strains. Although food-borne strains of cluster B were not clearly associated with disease, serotypes of important pathogens, such as O91:H21 and O113:H21, were in this cluster and closely related to the food-borne strains. Clonal analysis demonstrated eight closely related genetic groups of food-borne STEC and HUSEC strains that shared the same ST and were similar in their virulence gene composition. These groups should be considered with respect to their potential for human infection.

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Clinical and Molecular Correlates of Escherichia coli Bloodstream Infection from Two Geographically Diverse Centers in Rochester, Minnesota, and Singapore

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00937-18 ◽

2018 ◽

Vol 62 (10) ◽

Cited By ~ 5

Author(s):

Shehara M. Mendis ◽

Shawn Vasoo ◽

Brian D. Johnston ◽

Stephen B. Porter ◽

Scott A. Cunningham ◽

...

Keyword(s):

Escherichia Coli ◽

Odds Ratio ◽

Virulence Gene ◽

Fluoroquinolone Resistance ◽

Content Type ◽

E Coli ◽

Gene Profiles ◽

Clonal Distribution ◽

To Receive ◽

Community Onset

ABSTRACT Escherichia coli bacteremia is caused mainly by sequence type complex 131 (STc131) and two clades within its fluoroquinolone-resistance-associated H30 subclone, H30R1 and H30Rx. We examined clinical and molecular correlates of E. coli bacteremia in two geographically distinct centers. We retrospectively studied 251 unique E. coli bloodstream isolates from 246 patients (48 from the Mayo Clinic, Rochester, MN [MN], and 198 from Tan Tock Seng Hospital, Singapore [SG]), from October 2013 through March 2014. Isolates underwent PCR for phylogroup, STc, blaCTX-M type, and virulence gene profiles, and medical records were reviewed. Although STc131 accounted for 25 to 27% of all E. coli bacteremia isolates at each site, its extended-spectrum-β-lactamase (ESBL)-associated H30Rx clade was more prominent in SG than in MN (15% versus 4%; P = 0.04). In SG only, patients with STc131 (versus other E. coli STc isolates) were more likely to receive inactive initial antibiotics (odds ratio, 2.8; P = 0.005); this was true specifically for patients with H30Rx (odds ratio, 7.0; P = 0.005). H30Rx comprised 16% of community-onset bacteremia episodes in SG but none in MN. In SG, virulence scores were higher for H30Rx than for H30R1, non-H30 STc131, and non-STc131 isolates (P < 0.02 for all comparisons). At neither site did mortality differ by clonal status. The ESBL-associated H30Rx clade was more prevalent and more often of community onset in SG, where it predicted inactive empirical treatment. The clonal distribution varies geographically and has potentially important clinical implications. Rapid susceptibility testing and clonal diagnostics for H30/H30Rx might facilitate earlier prescribing of active therapy.

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Role of enteric pathogens in the aetiology of neonatal diarrhoea in lambs and goat kids in Spain

Epidemiology and Infection ◽

10.1017/s0950268800001321 ◽

1996 ◽

Vol 117 (1) ◽

pp. 203-211 ◽

Cited By ~ 80

Author(s):

M. Muñoz ◽

M. Álvarez ◽

I. Lanza ◽

P. Cármenes

Keyword(s):

Escherichia Coli ◽

Synergistic Effect ◽

Cryptosporidium Parvum ◽

Clinical Characteristics ◽

Enteric Pathogens ◽

E Coli ◽

Neonatal Diarrhoea ◽

Group A ◽

Group B

SummaryFaeces samples from diarrhoeic and non-diarrhoeic lambs and goat kids aged 1–45 days were examined for enteric pathogens.Cryptosporidium parvumwas detected in both diarrhoeic lambs (45%) and goat kids (42%) but not in non-diarrhoeic animals. F5+(K99+) and/or F41+Escherichia colistrains were isolated from 26% and 22% of the diarrhoeic lambs and goat kids, respectively, although these strains, which did not produce enterotoxins ST I or LT I, were found with similar frequencies in non-diarrhoeic animals. A F5−F41−ST I+E. colistrain was isolated from a diarrhoeic lamb (0·6%). VerotoxigenicE. coliwas isolated from both diarrhoeic and non-diarrhoeic lambs (4·1% and 8·2%, respectively) and there was no association between infection and diarrhoea. The prevalence of group A rotavirus infection in diarrhoeic lambs was very low (2·1%). Groups A and B rotaviruses were detected in three (8·1%) and five (13·5%) diarrhoeic goat kids from two single outbreaks. Group C rotaviruses were detected in four non-diarrhoeic goat kids. An association of diarrhoea and infection was demonstrated only for group B rotavirus.Clostridium perfringenswas isolated from 10·8% of the diarrhoeic goat kids but not from non-diarrhoeic goat kids or lambs.Salmonella arizonaewas isolated from a diarrhoeic goat kid (2·7%) and the clinical characteristics of the outbreaks where these two latter enteropathogens were found different from the rest. Picobirnaviruses were detected in a diarrhoeic lamb. No coronaviruses were detected using a bovine coronavirus ELISA. No evidence was found of synergistic effect between the agents studied. Enteric pathogens were not found in four (8·7%) and three (20%) outbreaks of diarrhoea in lambs and goat kids, respectively.

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Intestine and Environment of the Chicken as Reservoirs for Extraintestinal Pathogenic Escherichia coli Strains with Zoonotic Potential

Applied and Environmental Microbiology ◽

10.1128/aem.01324-08 ◽

2008 ◽

Vol 75 (1) ◽

pp. 184-192 ◽

Cited By ~ 133

Author(s):

Christa Ewers ◽

Esther-Maria Antï¿½o ◽

Ines Diehl ◽

Hans-C. Philipp ◽

Lothar H. Wieler

Keyword(s):

Escherichia Coli ◽

Virulence Gene ◽

Infection Model ◽

E Coli ◽

Gene Profiles ◽

Pathogenic Escherichia Coli ◽

Zoonotic Risk ◽

Resistant Strains ◽

Genetic Pool

ABSTRACT Although research has increasingly focused on the pathogenesis of avian pathogenic Escherichia coli (APEC) infections and the “APEC pathotype” itself, little is known about the reservoirs of these bacteria. We therefore compared outbreak strains isolated from diseased chickens (n = 121) with nonoutbreak strains, including fecal E. coli strains from clinically healthy chickens (n = 211) and strains from their environment (n = 35) by determining their virulence gene profiles, phylogenetic backgrounds, responses to chicken serum, and in vivo pathogenicities in a chicken infection model. In general, by examining 46 different virulence-associated genes we were able to distinguish the three groups of avian strains, but some specific fecal and environmental isolates had a virulence gene profile that was indistinguishable from that determined for outbreak strains. In addition, a substantial number of phylogenetic EcoR group B2 strains, which are known to include potent human and animal extraintestinal pathogenic E. coli (ExPEC) strains, were identified among the APEC strains (44.5%) as well as among the fecal E. coli strains from clinically healthy chickens (23.2%). Comparably high percentages (79.2 to 89.3%) of serum-resistant strains were identified for all three groups of strains tested, bringing into question the usefulness of this phenotype as a principal marker for extraintestinal virulence. Intratracheal infection of 5-week-old chickens corroborated the pathogenicity of a number of nonoutbreak strains. Multilocus sequence typing data revealed that most strains that were virulent in chicken infection experiments belonged to sequence types that are almost exclusively associated with extraintestinal diseases not only in birds but also in humans, like septicemia, urinary tract infection, and newborn meningitis, supporting the hypothesis that not the ecohabitat but the phylogeny of E. coli strains determines virulence. These data provide strong evidence for an avian intestinal reservoir hypothesis which could be used to develop intestinal intervention strategies. These strains pose a zoonotic risk because either they could be transferred directly from birds to humans or they could serve as a genetic pool for ExPEC strains.

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Molecular Epidemiology and Genome Dynamics of New Delhi Metallo-β-Lactamase-Producing Extraintestinal Pathogenic Escherichia coli Strains from India

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01345-16 ◽

2016 ◽

Vol 60 (11) ◽

pp. 6795-6805 ◽

Cited By ~ 32

Author(s):

Amit Ranjan ◽

Sabiha Shaik ◽

Agnismita Mondal ◽

Nishant Nandanwar ◽

Arif Hussain ◽

...

Keyword(s):

Escherichia Coli ◽

Effective Means ◽

Genomic Analysis ◽

Virulence Gene ◽

Carbapenem Resistance ◽

Control Measures ◽

Large Sample Size ◽

Gene Repertoire ◽

Content Type ◽

E Coli

ABSTRACTThe global dissemination and increasing incidence of carbapenem-resistant, Gram-negative organisms have resulted in acute public health concerns. Here, we present a retrospective multicenter study on molecular characterization of metallo-β-lactamase (MBL)-producing clinicalEscherichia coliisolates recovered from extraintestinal infections in two hospitals in Pune, India. We screened a large sample size of 510E. coliisolates for MBL production wherein we profiled their molecular determinants, antimicrobial resistance phenotypes, functional virulence properties, genomic features, and transmission dynamics. Approximately 8% of these isolates were MBL producers, the majority of which were of the NDM-1 (69%) type, followed by NDM-5 (19%), NDM-4 (5.5%), and NDM-7 (5.5%). MBL producers were resistant to all antibiotics tested except for colistin, fosfomycin, and chloramphenicol, which were effective to various extents. Plasmids were found to be an effective means of dissemination of NDM genes and other resistance traits. All MBL producers adhered to and invaded bladder epithelial (T24) cells and demonstrated significant serum resistance. Genomic analysis of MBL-producingE. coliisolates revealed higher resistance but a moderate virulence gene repertoire. A subset of NDM-1-positiveE. coliisolates was identified as dominant sequence type 101 (ST101) while two strains belonging to ST167 and ST405 harbored NDM-5. A majority of MBL-producingE. colistrains revealed unique genotypes, suggesting that they were clonally unrelated. Overall, the coexistence of virulence and carbapenem resistance in clinicalE. coliisolates is of serious concern. Moreover, the emergence of NDM-1 among the globally dominantE. coliST101 isolates warrants stringent surveillance and control measures.

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Draft Genomic Sequences of Nine Extraintestinal Pathogenic Escherichia coli Isolates from Retail Chicken Skin

Microbiology Resource Announcements ◽

10.1128/mra.00859-18 ◽

2018 ◽

Vol 7 (7) ◽

Cited By ~ 2

Author(s):

Aixia Xu ◽

Shannon Tilman ◽

Kristy Wisser-Parker ◽

O. Joseph Scullen ◽

Christopher H. Sommers

Keyword(s):

Escherichia Coli ◽

Food Safety ◽

Genomic Sequences ◽

Content Type ◽

E Coli ◽

Safety Research ◽

Pathogenic Escherichia Coli ◽

Chicken Skin

Extraintestinal pathogenic Escherichia coli strains were isolated from retail chicken skin. Here, we report the draft genomic sequences for these nine E. coli isolates, which are currently being used in agricultural and food safety research.

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Sequencing and Functional Annotation of Avian Pathogenic Escherichia coli Serogroup O78 Strains Reveal the Evolution of E. coli Lineages Pathogenic for Poultry via Distinct Mechanisms

Infection and Immunity ◽

10.1128/iai.00585-12 ◽

2012 ◽

Vol 81 (3) ◽

pp. 838-849 ◽

Cited By ~ 52

Author(s):

Francis Dziva ◽

Heidi Hauser ◽

Thomas R. Connor ◽

Pauline M. van Diemen ◽

Graham Prescott ◽

...

Keyword(s):

Escherichia Coli ◽

Core Genome ◽

Systemic Disease ◽

Genomic Islands ◽

Content Type ◽

E Coli ◽

Group 4 ◽

Pathogenic Escherichia Coli ◽

Transposon Mutants ◽

Avian Disease

ABSTRACTAvian pathogenicEscherichia coli(APEC) causes respiratory and systemic disease in poultry. Sequencing of a multilocus sequence type 95 (ST95) serogroup O1 strain previously indicated that APEC resemblesE. colicausing extraintestinal human diseases. We sequenced the genomes of two strains of another dominant APEC lineage (ST23 serogroup O78 strains χ7122 and IMT2125) and compared them to each other and to the reannotated APEC O1 sequence. For comparison, we also sequenced a human enterotoxigenicE. coli(ETEC) strain of the same ST23 serogroup O78 lineage. Phylogenetic analysis indicated that the APEC O78 strains were more closely related to human ST23 ETEC than to APEC O1, indicating that separation of pathotypes on the basis of their extraintestinal or diarrheagenic nature is not supported by their phylogeny. The accessory genome of APEC ST23 strains exhibited limited conservation of APEC O1 genomic islands and a distinct repertoire of virulence-associated loci. In light of this diversity, we surveyed the phenotype of 2,185 signature-tagged transposon mutants of χ7122 following intra-air sac inoculation of turkeys. This procedure identified novel APEC ST23 genes that play strain- and tissue-specific roles during infection. For example, genes mediating group 4 capsule synthesis were required for the virulence of χ7122 and were conserved in IMT2125 but absent from APEC O1. Our data reveal the genetic diversity ofE. colistrains adapted to cause the same avian disease and indicate that the core genome of the ST23 lineage serves as a chassis for the evolution ofE. colistrains adapted to cause avian or human disease via acquisition of distinct virulence genes.

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