Know Your Enemy: Improved Understanding, Detection, Control, and Therapy for Shiga Toxin-Producing Escherichia coli Infection

A special issue of Microorganisms (ISSN 2076-2607). This special issue belongs to the section "Gut Microbiota".

Deadline for manuscript submissions: closed (1 April 2022) | Viewed by 33554

Special Issue Editors

Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB T1J 4B1, Canada
Interests: strategies for mitigation of fecal shedding of E. coli O157:H7 by cattle; including bacteriophage therapy; passive immunotherapy; electrolyzed oxidizing anode water; management strategies; and dietary intervention
Special Issues, Collections and Topics in MDPI journals
Department of Bacteria, Parasites, and Fungi, Unit of Foodborne Infections, Statens Serum Institute, Copenhagen, Denmark
Interests: molecular microbiology; pathogens; infection control
Special Issues, Collections and Topics in MDPI journals
Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2R3, Canada
Interests: Escherichia coli; gastroenteritis; foodborne pathogens; molecular epidemiology
Special Issues, Collections and Topics in MDPI journals
Canadian Food Inspection Agency, Lethbridge Laboratory, Lethbridge, AB, Canada
Interests: genomics; machine learning; bioinformatics; microbiology
Special Issues, Collections and Topics in MDPI journals
Department of Pediatric Nephrology, Amalia Children’s Hospital, Radboud University Medical Center Nijmegen, Nijmegen, The Netherlands
Interests: kidney disease; pediatrics; hemolytic uremic syndrome; thrombotic microangiopathy; complement
Special Issues, Collections and Topics in MDPI journals
Enteric Diseases Epidemiology Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA
Interests: illnesses caused by enteric bacteria (Campylobacter, Clostridium botulinum, E. coli, Listeria, Salmonella, Shigella, Vibrio, and other bacteria)
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Verotoxigenic Escherichia coli (VTEC), also called Shiga toxin-producing Escherichia coli (STEC), are major pathogens transmitted by food, water, animals and their environment, and directly from one person to another. They typically cause diarrheal illness but can cause severe systemic disease, particularly in children and the elderly. Virulence is associated with a type III secretion system, which enables injection of bacterial effector proteins into host cells. In addition, Shiga toxins damage the kidneys. No specific treatment is available for STEC infection. A better understanding of the pathogenesis and epidemiology of STEC infection is needed. This includes improved detection, understanding of reservoirs, control and detection in the food chain, and an understanding of STEC ecology from a One Health perspective. For this Special Issue, we invite you to submit a review or original research article related to STEC detection, pathogenesis, epidemiology, or ecology that reflects the scientific community’s continued efforts to prevent and ameliorate STEC infections.

This Special Issue will contain papers related to STEC/VTEC research and will accompany the online meetings of VTEC 2021 (https://vtec2021.org/may-11-2021/). The in-person meeting of VTEC 2021 that was to be held in Banff, Alberta, Canada has been rescheduled to May 2023 due to COVD-19. This online meeting will serve as a momentum-building event while we work towards meeting in person again soon.

Prof. Dr. Tim A. McAllister
Dr. Flemming Scheutz
Prof. Dr. Linda Chui
Dr. Chad R. Laing
Dr. Nicole Van De Kar
Dr. Kim Stanford
Dr. Patricia Griffin
Guest Editors

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Keywords

  • foodborne bacteria
  • bacterial pathogenesis
  • host-pathogen interactions
  • gut microbiota
  • STEC
  • VTEC E. coli
  • epidemiology
  • microbial ecology

Published Papers (13 papers)

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Research

23 pages, 1114 KiB  
Article
Comparative Genomics Applied to Systematically Assess Pathogenicity Potential in Shiga Toxin-Producing Escherichia coli O145:H28
Microorganisms 2022, 10(5), 866; https://doi.org/10.3390/microorganisms10050866 - 21 Apr 2022
Cited by 6 | Viewed by 1623
Abstract
Shiga toxin-producing Escherichia coli (STEC) O145:H28 can cause severe disease in humans and is a predominant serotype in STEC O145 environmental isolates. Here, comparative genomics was applied to a set of clinical and environmental strains to systematically evaluate the pathogenicity potential in environmental [...] Read more.
Shiga toxin-producing Escherichia coli (STEC) O145:H28 can cause severe disease in humans and is a predominant serotype in STEC O145 environmental isolates. Here, comparative genomics was applied to a set of clinical and environmental strains to systematically evaluate the pathogenicity potential in environmental strains. While the core genes-based tree separated all O145:H28 strains from the non O145:H28 reference strains, it failed to segregate environmental strains from the clinical. In contrast, the accessory genes-based tree placed all clinical strains in the same clade regardless of their genotypes or serotypes, apart from the environmental strains. Loss-of-function mutations were common in the virulence genes examined, with a high frequency in genes related to adherence, autotransporters, and the type three secretion system. Distinct differences in pathogenicity islands LEE, OI-122, and OI-57, the acid fitness island, and the tellurite resistance island were detected between the O145:H28 and reference strains. A great amount of genetic variation was detected in O145:H28, which was mainly attributed to deletions, insertions, and gene acquisition at several chromosomal “hot spots”. Our study demonstrated a distinct virulence gene repertoire among the STEC O145:H28 strains originating from the same geographical region and revealed unforeseen contributions of loss-of-function mutations to virulence evolution and genetic diversification in STEC. Full article
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9 pages, 1721 KiB  
Article
Epidemiology of Non-O157 Shiga Toxin-Producing Escherichia coli in the Province of Alberta, Canada, from 2018 to 2021
Microorganisms 2022, 10(4), 814; https://doi.org/10.3390/microorganisms10040814 - 14 Apr 2022
Cited by 4 | Viewed by 1920
Abstract
Non-O157 serogroups contribute significantly to the burden of disease caused by Shiga toxin-producing Escherichia coli (STEC) and have been underrecognized by traditional detection algorithms. We described the epidemiology of non-O157 STEC in Alberta, Canada for the period of 2018 to 2021. All non-O157 [...] Read more.
Non-O157 serogroups contribute significantly to the burden of disease caused by Shiga toxin-producing Escherichia coli (STEC) and have been underrecognized by traditional detection algorithms. We described the epidemiology of non-O157 STEC in Alberta, Canada for the period of 2018 to 2021. All non-O157 STEC isolated from clinical samples were submitted for serotyping and qPCR targeting the stx1 and stx2 genes. A total of 729 isolates were identified. Increased detection occurred over the summer months, peaking in July. Patients 18 years and younger made up 42.4% of cases, with 31.1% in those 0–9 years of age. There was a slight female predominance (399/729, 54.7%) A total of 50 different serogroups were detected; the most common were O26 (30.3%), O103 (15.9%), O111 (12.8%), O121 (11.0%), O118 (3.3%) and O71 (2.9%). These six serogroups made up 76.2% of all isolates. In total, 567 (77.8%) were positive for stx1, 114 (15.6%) were positive for stx2 and 48 (6.6%) were positive for both stx1 and stx2. A wide variety of non-O157 serogroups have been detected in Alberta, with the most frequent serogroups differing from other locations. These results highlight the need for further characterization of their virulence factors and clinical impact. Full article
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18 pages, 9540 KiB  
Article
The Importance of Shiga Toxin-Producing Escherichia coli O145:NM[H28]/H28 Infections in Argentina, 1998–2020
Microorganisms 2022, 10(3), 582; https://doi.org/10.3390/microorganisms10030582 - 07 Mar 2022
Cited by 5 | Viewed by 2090
Abstract
Shiga toxin-producing Escherichia coli (STEC) is known as a pathogen associated with food-borne diseases. The STEC O145 serogroup has been related with acute watery diarrhea, bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Argentina has the highest rate of HUS worldwide with [...] Read more.
Shiga toxin-producing Escherichia coli (STEC) is known as a pathogen associated with food-borne diseases. The STEC O145 serogroup has been related with acute watery diarrhea, bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Argentina has the highest rate of HUS worldwide with 70% of the cases associated with STEC infections. We aimed to describe the epidemiology and genetic diversity of STEC O145 strains isolated across Argentina between 1998–2020. The strains isolated from 543 cases of human disease and four cattle, were pheno-genotipically characterized. Sequencing of five strains was performed. The strains were serotyped as O145:NM[H28]/H28, O145:H25, and O145:HNT, and mainly characterized as O145:NM[H28]/stx2a/eae/ehxA (98.1%). The results obtained by sequencing were consistent with those obtained by traditional methods and additional genes involved in different mechanisms of the pathogen were observed. In this study, we confirmed that STEC O145 strains are the second serogroup after O157 and represent 20.3% of HUS cases in Argentina. The frequency of STEC O145 and other significant serogroups is of utmost importance for public health in the country. This study encourages the improvement of the surveillance system to prevent severe cases of human disease. Full article
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9 pages, 637 KiB  
Article
Molecular Detection of Non-O157 Shiga Toxin-Producing Escherichia coli (STEC) Directly from Stool Using Multiplex qPCR Assays
Microorganisms 2022, 10(2), 329; https://doi.org/10.3390/microorganisms10020329 - 31 Jan 2022
Cited by 2 | Viewed by 2391
Abstract
Non-O157 Shiga toxin-producing E. coli (STEC) can cause outbreaks that have great economic and health impact. Since the implementation of STEC screening in Alberta in 2018, it is also essential to have a molecular serotyping method with faster turnaround time for cluster identification [...] Read more.
Non-O157 Shiga toxin-producing E. coli (STEC) can cause outbreaks that have great economic and health impact. Since the implementation of STEC screening in Alberta in 2018, it is also essential to have a molecular serotyping method with faster turnaround time for cluster identification and surveillance purposes. This study sought to perform molecular serotyping of the top six non-O157 (O26, O45, O103, O111, O121 and O145) STEC serotypes directly from stools and enrichment broths compared to conventional methods on isolates. Multiplex, serotyping qPCR assays were used to determine sensitivity and specificity of the top six non-O157 STEC serotypes. Sensitivity and specificity were assessed for both singleplex and multiplex qPCR assays for comparison of the top six serotypes. Blinded stool specimens (n = 116) or broth samples (n = 482) submitted from frontline microbiology laboratories for STEC investigation were analyzed by qPCR. Both singleplex and multiplex assays were comparable, and we observed 100% specificity with a limit of detection of 100 colony-forming units per mL. Direct molecular serotyping from stool specimens mostly correlated (88%) with conventional serotyping of the cultured isolate. In cases of discordant serotypes, the top six non-O157 STEC mixed infections were identified and confirmed by culture and conventional serotyping. Detection of non-O157 STEC can be done directly from stool specimens using multiplex PCR assays with the ability to identify mixed infections, which would otherwise remain undetected by conventional serotyping of a single colony. This method can be easily implemented into a frontline diagnostic laboratory to enhance surveillance of non-O157 STEC, as more frontline microbiology laboratories move to culture independent assays. Full article
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12 pages, 1736 KiB  
Article
Nitric Oxide Induced stx2 Expression Is Inhibited by the Nitric Oxide Reductase, NorV, in a Clade 8 Escherichia coli O157:H7 Outbreak Strain
Microorganisms 2022, 10(1), 106; https://doi.org/10.3390/microorganisms10010106 - 05 Jan 2022
Viewed by 1168
Abstract
Escherichia coli O157:H7 pathogenesis is due to Shiga toxin (Stx) production, though variation in virulence has been observed. Clade 8 strains, for instance, were shown to overproduce Stx and were more common among hemolytic uremic syndrome cases. One candidate gene, norV, which [...] Read more.
Escherichia coli O157:H7 pathogenesis is due to Shiga toxin (Stx) production, though variation in virulence has been observed. Clade 8 strains, for instance, were shown to overproduce Stx and were more common among hemolytic uremic syndrome cases. One candidate gene, norV, which encodes a nitric oxide (NO) reductase found in a clade 8 O157:H7 outbreak strain (TW14359), was thought to impact virulence. Hence, we screened for norV in 303 O157 isolates representing multiple clades, examined stx2 expression following NO exposure in TW14359 for comparison to an isogenic mutant (ΔnorV), and evaluated survival in THP-1 derived macrophages. norV was intact in strains representing clades 6–9, whereas a 204 bp deletion was found in clades 2 and 3. During anaerobic growth, NO induced stx2 expression in TW14359. A similar increase in stx2 expression was observed for the ΔnorV mutant in anaerobiosis, though it was not impaired in its ability to survive within macrophages relative to TW14359. Altogether, these data suggest that NO enhances virulence by inducing Stx2 production in TW14359, and that toxin production is inhibited by NorV encoded by a gene found in most clade 8 strains. The mechanism linked to these responses, however, remains unclear and likely varies across genotypes. Full article
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11 pages, 1566 KiB  
Article
Single- and Dual-Species Biofilm Formation by Shiga Toxin-Producing Escherichia coli and Salmonella, and Their Susceptibility to an Engineered Peptide WK2
Microorganisms 2021, 9(12), 2510; https://doi.org/10.3390/microorganisms9122510 - 03 Dec 2021
Cited by 3 | Viewed by 1606
Abstract
Shiga toxin-producing Escherichia coli (STEC) and Salmonella enterica are important foodborne pathogens capable of forming both single- and multi-species biofilms. In this study, the mono- and dual-species biofilms were formed by STEC O113:H21 and Salmonella enterica serovar Choleraesuis 10708 on stainless steel in [...] Read more.
Shiga toxin-producing Escherichia coli (STEC) and Salmonella enterica are important foodborne pathogens capable of forming both single- and multi-species biofilms. In this study, the mono- and dual-species biofilms were formed by STEC O113:H21 and Salmonella enterica serovar Choleraesuis 10708 on stainless steel in the presence of beef juice over 5 d at 22 °C. The dual-species biofilm mass was substantially (p < 0.05) greater than that produced by STEC O113:H21 or S. Choleraesuis 10708 alone. However, numbers (CFU/mL) of S. Choleraesuis 10708 or STEC O113:H21 cells in the dual-species biofilm were (p < 0.05) lower than their respective counts in single-species biofilms. In multi-species biofilms, the sensitivity of S. Choleraesuis 10708 to the antimicrobial peptide WK2 was reduced, but it was increased for STEC O113:H21. Visualization of the temporal and spatial development of dual-species biofilms using florescent protein labeling confirmed that WK2 reduced cell numbers within biofilms. Collectively, our results highlight the potential risk of cross-contamination by multi-species biofilms to food safety and suggest that WK2 may be developed as a novel antimicrobial or sanitizer for the control of biofilms on stainless steel. Full article
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7 pages, 699 KiB  
Article
Characterization of Clinical Escherichia coli Strains Producing a Novel Shiga Toxin 2 Subtype in Sweden and Denmark
Microorganisms 2021, 9(11), 2374; https://doi.org/10.3390/microorganisms9112374 - 17 Nov 2021
Cited by 15 | Viewed by 2160
Abstract
Shiga toxin (Stx) is the key virulence factor in the Shiga Toxin-Producing Escherichia coli (STEC), which can cause diarrhea and hemorrhagic colitis with potential life-threatening complications. There are two major types of Stx: Stx1 and Stx2. Several Stx1/Stx2 subtypes have been identified in [...] Read more.
Shiga toxin (Stx) is the key virulence factor in the Shiga Toxin-Producing Escherichia coli (STEC), which can cause diarrhea and hemorrhagic colitis with potential life-threatening complications. There are two major types of Stx: Stx1 and Stx2. Several Stx1/Stx2 subtypes have been identified in E. coli, varying in sequences, toxicity and host specificity. Here, we report a novel Stx2 subtype (designated Stx2m) from three clinical E. coli strains isolated from diarrheal patients and asymptomatic carriers in Sweden and Denmark. The Stx2m toxin was functional and exhibited cytotoxicity in vitro. The two Swedish Stx2m-producing strains belonged to the same serotype O148:H39 and Multilocus Sequencing Typing (MLST) Sequence Type (ST) 5825, while the Danish strain belonged to the O96:H19 serotype and ST99 type. Whole-genome sequencing (WGS) data analysis revealed that the three Stx2m-producing strains harbored additional virulence genes and the macrolide resistance gene mdf (A). Our findings expand the pool of Stx2 subtypes and highlight the clinical significance of emerging STEC variants. Given the clinical relevance of the Stx2m-producing strains, we propose to include Stx2m in epidemiological surveillance of STEC infections and clinical diagnosis. Full article
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13 pages, 2777 KiB  
Article
The Shiga Toxin Receptor Globotriaosylceramide as Therapeutic Target in Shiga Toxin E. coli Mediated HUS
Microorganisms 2021, 9(10), 2157; https://doi.org/10.3390/microorganisms9102157 - 16 Oct 2021
Cited by 6 | Viewed by 2254
Abstract
In 90% of the cases, childhood hemolytic uremic syndrome (HUS) is caused by an infection with the Shiga toxin (Stx) producing E. coli bacteria (STEC-HUS). Stx preferentially binds to its receptor, the glycosphingolipid, globotriaosylceramide (Gb3), present on the surface of human kidney cells [...] Read more.
In 90% of the cases, childhood hemolytic uremic syndrome (HUS) is caused by an infection with the Shiga toxin (Stx) producing E. coli bacteria (STEC-HUS). Stx preferentially binds to its receptor, the glycosphingolipid, globotriaosylceramide (Gb3), present on the surface of human kidney cells and various organs. In this study, the glycosphingolipid pathway in endothelial cells was explored as therapeutic target for STEC-HUS. Primary human glomerular microvascular endothelial cells (HGMVECs) and human blood outgrowth endothelial cells (BOECs) in quiescent and activated state were pre-incubated with Eliglustat (Cerdelga®; glucosylceramide synthase inhibitor) or Agalsidase alpha (Replagal®; human cell derived alpha-galactosidase) in combination with various concentrations of Stx2a. Preincubation of endothelial cells with Agalsidase resulted in an increase of α-galactosidase activity in the cell, but had no effect on the binding of Stx to the cell surface when compared to control cells. However, the incubation of both types of endothelial cells incubated with or without the pro-inflammatory cytokine TNFα in combination with Eliglustat resulted in significant decrease of Stx binding to the cell surface, a decrease in protein synthesis by Stx2a, and diminished cellular Gb3 levels as compared to control cells. In conclusion, inhibition of the synthesis of Gb3 may be a potential future therapeutic target to protect against (further) endothelial damage caused by Stx. Full article
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14 pages, 506 KiB  
Article
Risk of Hemolytic Uremic Syndrome Related to Treatment of Escherichia coli O157 Infection with Different Antimicrobial Classes
Microorganisms 2021, 9(9), 1997; https://doi.org/10.3390/microorganisms9091997 - 21 Sep 2021
Cited by 4 | Viewed by 3202
Abstract
Treatment of Shiga toxin-producing Escherichia coli O157 (O157) diarrhea with antimicrobials might alter the risk of hemolytic uremic syndrome (HUS). However, full characterization of which antimicrobials might affect risk is lacking, particularly among adults. To inform clinical management, we conducted a case-control study [...] Read more.
Treatment of Shiga toxin-producing Escherichia coli O157 (O157) diarrhea with antimicrobials might alter the risk of hemolytic uremic syndrome (HUS). However, full characterization of which antimicrobials might affect risk is lacking, particularly among adults. To inform clinical management, we conducted a case-control study of residents of the FoodNet surveillance areas with O157 diarrhea during a 4-year period to assess antimicrobial class-specific associations with HUS among persons with O157 diarrhea. We collected data from medical records and patient interviews. We measured associations between treatment with agents in specific antimicrobial classes during the first week of diarrhea and development of HUS, adjusting for age and illness severity. We enrolled 1308 patients; 102 (7.8%) developed confirmed HUS. Antimicrobial treatment varied by age: <5 years (12.6%), 5–14 (11.5%), 15–39 (45.4%), ≥40 (53.4%). Persons treated with a β-lactam had higher odds of developing HUS (OR 2.80, CI 1.14–6.89). None of the few persons treated with a macrolide developed HUS, but the protective association was not statistically significant. Exposure to “any antimicrobial” was not associated with increased odds of HUS. Our findings confirm the risk of β-lactams among children with O157 diarrhea and extends it to adults. We observed a high frequency of inappropriate antimicrobial treatment among adults. Our data suggest that antimicrobial classes differ in the magnitude of risk for persons with O157 diarrhea. Full article
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14 pages, 1599 KiB  
Article
Potential Zoonotic Pathovars of Diarrheagenic Escherichia coli Detected in Lambs for Human Consumption from Tierra del Fuego, Argentina
Microorganisms 2021, 9(8), 1710; https://doi.org/10.3390/microorganisms9081710 - 11 Aug 2021
Cited by 4 | Viewed by 2073
Abstract
Diarrheagenic Escherichia coli (DEC) pathovars impact childhood health. The southern region of Argentina shows the highest incidence of hemolytic uremic syndrome (HUS) in children of the country. The big island of Tierra del Fuego (TDF) in Argentina registered an incidence of five cases/100,000 [...] Read more.
Diarrheagenic Escherichia coli (DEC) pathovars impact childhood health. The southern region of Argentina shows the highest incidence of hemolytic uremic syndrome (HUS) in children of the country. The big island of Tierra del Fuego (TDF) in Argentina registered an incidence of five cases/100,000 inhabitants of HUS in 2019. This work aimed to establish the prevalence of STEC, EPEC, and EAEC in lambs slaughtered in abattoirs from TDF as well as to characterize the phenotypes and the genotypes of the isolated pathogens. The prevalence was 26.6% for stx+, 5.7% for eae+, and 0.27% for aagR+/aaiC+. Twelve STEC isolates were obtained and belonged to the following serotypes: O70:HNT, O81:H21, O81:HNT, O102:H6, O128ab:H2, O174:H8, and O174:HNT. Their genotypic profiles were stx1c (2), stx1c/ehxA (3), stx2b/ehxA (1), stx1c/stx2b (2), and stx1c/stx2/ehxA (4). Six EPEC isolates were obtained and corresponded to five serotypes: O2:H40, O32:H8, O56:H6, O108:H21, and O177:H25. All the EPEC isolates were bfpA- and two were ehxA+. By XbaI-PFGE of 17 isolates, two clusters were identified. By antimicrobial susceptibility tests, 8/12 STEC and 5/6 EPEC were resistant to at least one antibiotic. This work provides new data to understand the ecology of DEC in TDF and confirms that ovine are an important carrier of these pathogens in the region. Full article
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14 pages, 2520 KiB  
Article
High Occurrence of Shiga Toxin-Producing Escherichia coli in Raw Meat-Based Diets for Companion Animals—A Public Health Issue
Microorganisms 2021, 9(8), 1556; https://doi.org/10.3390/microorganisms9081556 - 21 Jul 2021
Cited by 6 | Viewed by 4159
Abstract
Feeding pets raw meat-based diets (RMBDs) is becoming increasingly popular but comes with a risk of pathogenic bacteria, including Shiga toxin-producing Escherichia coli (STEC). In humans, STEC may cause gastrointestinal illnesses, including diarrhea, hemorrhagic colitis (HC), and the hemolytic uremic syndrome (HUS). The [...] Read more.
Feeding pets raw meat-based diets (RMBDs) is becoming increasingly popular but comes with a risk of pathogenic bacteria, including Shiga toxin-producing Escherichia coli (STEC). In humans, STEC may cause gastrointestinal illnesses, including diarrhea, hemorrhagic colitis (HC), and the hemolytic uremic syndrome (HUS). The aim of this study was to evaluate commercially available RMBDs with regard to the occurrence of STEC. Of 59 RMBD samples, 59% tested positive by real-time PCR for the presence of Shiga toxin genes stx1 and/or stx2. STECs were recovered from 41% of the 59 samples, and strains were subjected to serotyping and virulence gene profiling, using whole genome sequencing (WGS)-based methods. Of 28 strains, 29% carried stx2a or stx2d, which are linked to STEC with high pathogenic potential. Twenty different serotypes were identified, including STEC O26:H11, O91:H10, O91:H14, O145:H28, O146:H21, and O146:H28, which are within the most common non-O157 serogroups associated with human STEC-related illnesses worldwide. Considering the low infectious dose and potential severity of disease manifestations, the high occurrence of STEC in RMBDs poses an important health risk for persons handling raw pet food and persons with close contact to pets fed on RMBDs, and is of concern in the field of public health. Full article
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13 pages, 3298 KiB  
Article
Shiga Toxin-Producing Escherichia coli Outbreaks in the United States, 2010–2017
Microorganisms 2021, 9(7), 1529; https://doi.org/10.3390/microorganisms9071529 - 17 Jul 2021
Cited by 28 | Viewed by 4263
Abstract
Shiga toxin-producing Escherichia coli (STEC) cause illnesses ranging from mild diarrhea to ischemic colitis and hemolytic uremic syndrome (HUS); serogroup O157 is the most common cause. We describe the epidemiology and transmission routes for U.S. STEC outbreaks during 2010–2017. Health departments reported 466 [...] Read more.
Shiga toxin-producing Escherichia coli (STEC) cause illnesses ranging from mild diarrhea to ischemic colitis and hemolytic uremic syndrome (HUS); serogroup O157 is the most common cause. We describe the epidemiology and transmission routes for U.S. STEC outbreaks during 2010–2017. Health departments reported 466 STEC outbreaks affecting 4769 persons; 459 outbreaks had a serogroup identified (330 O157, 124 non-O157, 5 both). Among these, 361 (77%) had a known transmission route: 200 foodborne (44% of O157 outbreaks, 41% of non-O157 outbreaks), 87 person-to-person (16%, 24%), 49 animal contact (11%, 9%), 20 water (4%, 5%), and 5 environmental contamination (2%, 0%). The most common food category implicated was vegetable row crops. The distribution of O157 and non-O157 outbreaks varied by age, sex, and severity. A significantly higher percentage of STEC O157 than non-O157 outbreaks were transmitted by beef (p = 0.02). STEC O157 outbreaks also had significantly higher rates of hospitalization and HUS (p < 0.001). Full article
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17 pages, 2181 KiB  
Article
Annexin Induces Cellular Uptake of Extracellular Vesicles and Delays Disease in Escherichia coli O157:H7 Infection
Microorganisms 2021, 9(6), 1143; https://doi.org/10.3390/microorganisms9061143 - 26 May 2021
Cited by 9 | Viewed by 2510
Abstract
Enterohemorrhagic Escherichia coli secrete Shiga toxin and lead to hemolytic uremic syndrome. Patients have high levels of circulating prothrombotic extracellular vesicles (EVs) that expose phosphatidylserine and tissue factor and transfer Shiga toxin from the circulation into the kidney. Annexin A5 (AnxA5) binds to [...] Read more.
Enterohemorrhagic Escherichia coli secrete Shiga toxin and lead to hemolytic uremic syndrome. Patients have high levels of circulating prothrombotic extracellular vesicles (EVs) that expose phosphatidylserine and tissue factor and transfer Shiga toxin from the circulation into the kidney. Annexin A5 (AnxA5) binds to phosphatidylserine, affecting membrane dynamics. This study investigated the effect of anxA5 on EV uptake by human and murine phagocytes and used a mouse model of EHEC infection to study the effect of anxA5 on disease and systemic EV levels. EVs derived from human whole blood or HeLa cells were more readily taken up by THP-1 cells or RAW264.7 cells when the EVs were coated with anxA5. EVs from HeLa cells incubated with RAW264.7 cells induced phosphatidylserine exposure on the cells, suggesting a mechanism by which anxA5-coated EVs can bind to phagocytes before uptake. Mice treated with anxA5 for six days after inoculation with E. coli O157:H7 showed a dose-dependent delay in the development of clinical disease. Treated mice had lower levels of EVs in the circulation. In the presence of anxA5, EVs are taken up by phagocytes and their systemic levels are lower, and, as EVs transfer Shiga toxin to the kidney, this could postpone disease development. Full article
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