78 results on '"Non o157"'
Search Results
2. Longitudinal Characterization of Prevalence and Concentration of Shiga Toxin–Producing Escherichia coli Serogroups in Feces of Individual Feedlot Cattle
- Author
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David G. Renter, Andrea Dixon, Xiaorong Shi, Natalia Cernicchiaro, Charley A. Cull, and Raghavendra G. Amachawadi
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0303 health sciences ,040301 veterinary sciences ,030306 microbiology ,Feedlot cattle ,04 agricultural and veterinary sciences ,Beef cattle ,Biology ,bacterial infections and mycoses ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Microbiology ,Non o157 ,0403 veterinary science ,03 medical and health sciences ,fluids and secretions ,medicine ,bacteria ,Animal Science and Zoology ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Feces ,Food Science - Abstract
The objective of this study was to quantify the frequency, distribution, and variability of fecal shedding and super-shedding of Shiga toxin–producing Escherichia coli (STEC) serogroups O26, O45, O...
- Published
- 2020
3. Virulence Factors and Antimicrobial Resistance Patterns of Non-O157 Shiga Toxin-producing Escherichia coli Isolated from Different Sources at Sadat City
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Mohamed Sabry Abd Elraheam Elsyaed and Mary Mounir
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fluids and secretions ,Antibiotic resistance ,Geography, Planning and Development ,Virulence ,Development ,Biology ,Shiga toxin-producing Escherichia coli ,Non o157 ,Microbiology - Abstract
Aims: A great concern directed to non-O157 Shiga toxin-producing Escherichia coli (STEC) serotypes due to their public health importance. Detecting the existence, antimicrobial profiles, and virulence repertoire of different STEC serotypes from animals essential for human food are important. Study Design: This study aimed to investigate the presence of STEC in different hosts, the distribution pattern of stx1, stx2, eaeA, and hlyA genes encoding Shiga toxins 1 and 2, intimin, and enterohemolysin, respectively, and the antimicrobial resistance of the detected serotypes. Results: A total of 75 samples were collected, 20 fecal samples from broilers, 15 fecal samples from ducks, 20 beef samples, and 20 human urine samples. Escherichia coli was detected at a rate of 60/75 (80%) distributed as;17 (85%), 8 (53.3%), 15(75%), and 20 (100%) from broilers, ducks, human urine, and beef samples, respectively. There was a significant difference between the isolation rates of E. coli from different sources with p
- Published
- 2020
4. Molecular Characterization of Shiga Toxin Producing Escherichia coli Isolated From Both Diarrheic and Apparently Health Calves
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Amira Ahmed, Alaa Hussein, and Abd Elrahman Abd Elmagid
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Serotype ,Toxin ,animal diseases ,Shiga toxin ,Biology ,bacterial infections and mycoses ,Isolation (microbiology) ,medicine.disease_cause ,Non o157 ,Microbiology ,fluids and secretions ,medicine ,biology.protein ,bacteria ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Feces - Abstract
Shiga toxin producing Escherichia coli is a contaminant of food and water that causes a diarrheal syndrome followed by more severe disease of the kidneys and symptoms of the central nervous system in humans. The isolation of Shiga toxin producing Escherichia coli (STEC) from diarrheic and apparently health calves is difficult due to lack of differential phenotypic characteristics from nonpathogenic Escherichia coli. The improvement of molecular technology allows identification of both toxin and serogroup specific genetic determinants. In this study, 300 fecal samples from diarrheic and apparently healthy calves were screened for STEC using PCR targeting Shiga toxin determinants. In addition routine culture methods for isolating O157 and non O157 STEC were also performed. The screening assays of serotyping isolates revealed 7 (4.1%) of O157H7, 156 (92.8%) of non O157 and 5 (3.1%) for untypable strains. These included STEC serotypes of O157H7 and O26 from diarrheic samples, and O78, O55 and O126 from apparently healthy calves. The high rate of STEC isolation and the diversity of STEC serogroup from calves focus the light on the importance of calves as reservoir of E. coli as well as motivate us to improve biosecurity measures in dairy farms.
- Published
- 2019
5. Prevalence of Shiga toxin-producing Escherichia coli (STEC) O157:H7, Six non-O157 STECs, and Salmonella on beef carcasses in Provincially Licensed Abattoirs in Alberta, Canada
- Author
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Deana Rolheiser, Natisha Stashko, Chunu Mainali, Gary Gensler, Saida Essendoubi, and Iyla So
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Indicator organism ,Veterinary medicine ,Salmonella ,biology ,food and beverages ,Alberta canada ,Beef cattle ,medicine.disease_cause ,biology.organism_classification ,Enterobacteriaceae ,Non o157 ,fluids and secretions ,medicine ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Food Science ,Biotechnology - Abstract
From January to December 2016, Alberta Agriculture and Forestry (AAF) conducted a provincial survey of selected pathogens and indicator organisms on beef carcasses processed at Provincially Licensed Abattoirs (PLAs) in Alberta. The survey was conducted in seven small and medium scale slaughterhouses located in southern and northern Alberta that process beef cattle and cows. Paired samples were collected from the same carcass immediately after hide removal (pre-evisceration n = 401) and at pre-chill (n = 402) after application of a carcass wash and/or anti-microbial interventions. Swab samples were screened for the presence of Shiga toxin-producing Escherichia coli (STEC) O157:H7, six non-O157 STECs (O26, O45, O103, O111, O121 and O145), and Salmonella. In addition, samples were enumerated for indicator organisms (aerobic colony count (ACC), Enterobacteriaceae, coliforms, and generic E. coli). At pre-evisceration, 30 samples (7.4%) were confirmed positive for E. coli O157:H7; 13 samples (3.2%) were confirmed positive for non-O157 STEC; and 7 samples (1.7%) were confirmed positive for Salmonella. Pre-chill swabs had 21 samples (5.2%) positive for E. coli O157:H7, 16 samples (3.9%) positive for non-O157 STEC, and 1 sample (0.2%) positive for Salmonella. At pre-chill the prevalence of Salmonella was significantly lower (P
- Published
- 2019
6. Determination of the changes in the gastric fluid endurance of O157 and non-O157 Shiga toxin-producing Escherichia coli during storage of experimentally produced beef frankfurter
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Abdullah Dikici, Sümeyye Betül Bozatli, and Bülent Ergönül
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0303 health sciences ,education.field_of_study ,Gastric fluid ,030306 microbiology ,Chemistry ,Pathogen resistance ,Population ,0402 animal and dairy science ,Acid resistance ,04 agricultural and veterinary sciences ,bacterial infections and mycoses ,medicine.disease_cause ,040201 dairy & animal science ,Non o157 ,03 medical and health sciences ,fluids and secretions ,medicine ,Original Article ,Food science ,education ,Escherichia coli ,Pathogen ,Shiga toxin-producing Escherichia coli ,Food Science - Abstract
Resistance of Shiga toxin-producing Escherichia coli (STEC) O157:H7 and serogroups O103, O26 and O145 to synthetic gastric fluid (SGF, pH 1.5) were investigated during frankfurter storage. Pathogens were inoculated (5 ± 1 log(10 )cfu g(−1)) on frankfurters and frankfurters were stored at 4 °C for 75 days in vacuum packages. Population changes of the competitive flora and STEC, changes in the pH of the frankfurters and resistance of STEC to SGF were monitored on days 0, 15, 30, 45, 60 and 75 of frankfurter storage. Direct synthetic gastric fluid (DSGF) challenges were also conducted to assess pathogen resistance without being effected by frankfurters, by inoculating pathogen cultures directly into SGF. Results showed that acid resistance of O145 and O26 was stronger than that of O103 and O157 during frankfurter storage. Resistance of O103 to SGF was better than that of O157 during frankfurter storage but, was similar to that of O157 during DSGF challenges. Results indicate that acid resistance of some strains of STEC pathogens might differentiate during storage of frankfurters. Different resistance capabilities to SGF were observed in the STEC strains when inoculated and stored on frankfurters than directly inoculated in the SGF.
- Published
- 2020
7. The effects of environmental factors on the prevalence and diversity of bacteriophages lytic against the top six <scp>non‐O157</scp> Shiga toxin‐producing <scp> Escherichia coli </scp> on an organic farm
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Angeline L. Hsu, Yen-Te Liao, Vivian C.H. Wu, Alexandra Salvador, Marion Lennon, and Valerie M. Lavenburg
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Lytic cycle ,Organic farming ,Parasitology ,Biology ,Microbiology ,Shiga toxin-producing Escherichia coli ,Non o157 ,Food Science - Published
- 2020
8. Isolation and characterization of non-O157 Shiga toxin-producing Escherichia coli (STEC) isolated from retail ground beef in Santiago, Chile
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Paola Navarrete, María Fernanda Jiménez, Angélica Reyes-Jara, Leonela Díaz, Magaly Toro, and Daniel Rivera
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0301 basic medicine ,Veterinary medicine ,Virulence Factors ,030106 microbiology ,Virulence ,Food Contamination ,Biology ,medicine.disease_cause ,Microbiology ,Virulence factor ,Non o157 ,03 medical and health sciences ,fluids and secretions ,STX2 ,medicine ,Animals ,Chile ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Shiga-Toxigenic Escherichia coli ,Escherichia coli Proteins ,bacterial infections and mycoses ,Isolation (microbiology) ,biology.organism_classification ,Red Meat ,030104 developmental biology ,bacteria ,Cattle ,Bacteria ,Food Science - Abstract
Shiga toxin-producing Escherichia coli (STEC) is one of the main cause of foodborne disease worldwide, but isolation rates or characteristics of this bacteria from ground beef in Chile are unknown. The present study aimed to isolate and characterize non-O157 STEC from ground beef sold at retail in the city of Santiago, Chile. We analyzed 430 ground beef samples for the presence of STEC, and isolated the microorganism in 10% of samples (43/430). We obtained 56 isolates from the 43 positive samples; 55 of these (98.2%) fermented sorbitol. Most isolates (98.2%; 55/56) showed β-glucoronidase activity, and only six (10.7%; 6/56) were resistant to tellurite. Among the virulence factors studied (stx1, stx2, eae, and hlyA), stx2 was the only virulence factor in 41% of the isolates (23/56), whereas 10.7% (6/56) of isolates carried a combination of three virulence factors (stx1 + stx2 + hlyA). None of the isolates carried the gene eae. Finally, isolates were neither serogroups O157 nor “big six”. In conclusion, ground beef sold in Santiago, Chile is contaminated with STEC; however, further studies are required for understanding their virulence potential.
- Published
- 2018
9. Are Reservoirs and Transmission Routes the Same or Different Between O157 and Non-O157 Shiga Toxin-Producing Escherichia coli?
- Author
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Hajime Kanamori and Hiroaki Baba
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Microbiology (medical) ,Shiga-Toxigenic Escherichia coli ,business.industry ,Escherichia coli O157 ,Non o157 ,law.invention ,Microbiology ,Phylogeography ,Infectious Diseases ,Transmission (mechanics) ,law ,Medicine ,Humans ,business ,Shiga toxin-producing Escherichia coli - Published
- 2019
10. Tellurite resistance profiles and performance of different chromogenic agars for detection of non-O157 Shiga toxin-producing Escherichia coli
- Author
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Ruyue Fan, Yanmei Xu, Shanshan Fu, Xiangning Bai, Yanwen Xiong, Hui Sun, and Hong Wang
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0301 basic medicine ,food.ingredient ,030106 microbiology ,Antineoplastic Agents ,Microbial Sensitivity Tests ,Escherichia coli O157 ,Serogroup ,medicine.disease_cause ,Microbiology ,Non o157 ,03 medical and health sciences ,chemistry.chemical_compound ,Minimum inhibitory concentration ,fluids and secretions ,food ,Drug Resistance, Bacterial ,Genotype ,medicine ,Agar ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Shiga-Toxigenic Escherichia coli ,Chemistry ,Chromogenic ,General Medicine ,Culture Media ,030104 developmental biology ,Tellurium ,Growth inhibition ,Food Science - Abstract
Shiga toxin-producing Escherichia coli (STEC) are globally important food-borne pathogens. The isolation of non-O157 STEC is a significant public health challenge due to the dramatic diversity of their phenotypes and genotypes. In the present study, 476 non-O157 STEC strains representing 95 different O-serogroups were used to evaluate tellurite resistance and the performance of 12 different chromogenic agars. Of 476 strains, only 108 (22.7%) strains showed the minimal inhibitory concentration (MIC) values for potassium tellurite being higher than 4μg/ml, and 96 (20.2%) strains harbored intact ter genes cluster. The presence of ter genes was significantly correlated with tellurite resistance. Six commercial chromogenic agars (TBX, MAC, SMAC, Rainbow® Agar O157, CHROMagar™ ECC, and Fluorocult O157) supported the growth of all strains. However, CT-SMAC, CHROMagar™ O157, and CHROMagar™ STEC agars exhibited 12.2%, 31.1%, and 38.0% of growth inhibition, respectively. Furthermore, 4.6%, 33.2%, and 45.0% of strains were inhibited on RBA-USDA, RBA-NT, and BCM O157 agar media. Variations in tellurite resistance and colony appearance might result in discrepant performance of non-O157 STEC recovery from different chromogenic agars. Using inclusive agars or less selective agar in combination with highly selective agar should be suggested to recover most non-O157 STEC strains, which would increase the probability of recovering STECs from complex background microflora.
- Published
- 2018
11. Shiga Toxin-Producing Escherichia coli Outbreaks in the United States, 2010–2017
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Danielle M. Tack, Brigette Gleason, Daniel C. Payne, Patricia M. Griffin, LaTonia C Richardson, Aimee L. Geissler, and Hannah M Kisselburgh
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0301 basic medicine ,Microbiology (medical) ,Veterinary medicine ,medicine.medical_specialty ,Shiga toxin-producing Escherichia coli (STEC) ,QH301-705.5 ,030106 microbiology ,medicine.disease_cause ,Microbiology ,Non o157 ,Food category ,03 medical and health sciences ,fluids and secretions ,0302 clinical medicine ,Virology ,Epidemiology ,medicine ,030212 general & internal medicine ,Biology (General) ,O157 ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,foodborne ,Transmission (medicine) ,business.industry ,Outbreak ,Diarrhea ,non-O157 ,outbreaks ,bacteria ,epidemiology ,medicine.symptom ,business - 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 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).
- Published
- 2021
12. Comparison of the fate of the top six non-O157 shiga-toxin producing Escherichia coli (STEC) and E. coli O157:H7 during the manufacture of dry fermented sausages
- Author
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Anli Gao, Phil Strange, Rafath Ahmed, and Sampathkumar Balamurugan
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0301 basic medicine ,Food Handling ,030106 microbiology ,Escherichia coli O157 ,medicine.disease_cause ,Microbiology ,Non o157 ,Foodborne Diseases ,03 medical and health sciences ,Bioreactors ,fluids and secretions ,medicine ,Animals ,Food microbiology ,Food science ,Desiccation ,Fermentation in food processing ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Log reduction ,Inoculation ,Chemistry ,Escherichia coli Proteins ,General Medicine ,Bacterial Load ,Meat Products ,030104 developmental biology ,Fermentation ,Food Science - Abstract
The study examined the relative fate of the top six non-O157 shiga-toxin producing Escherichia coli (STEC) and E. coli O157:H7 during the manufacture of dry fermented sausages (DFS). Three separate batches of sausages containing a five-strain cocktail for each serogroup and uninoculated control were manufactured and subjected to identical fermentation, maturation and dry curing conditions. Changes in physicochemical properties and inoculated STEC numbers were enumerated during the DFS production stages and log reduction and log reduction rates were calculated. Inoculation of very high concentrations (8logCFUg-1) of STEC in the sausage batter did not significantly (P>0.05) affect the changes in the pH, aw, moisture, protein, fat content compared to the uninoculated DFS. There was a significant (P 0.05) from each other. These results indicate that the lethality of DFS production processes observed against E. coli O157:H7 would result in a similar inactivation of the top six non-O157 STEC.
- Published
- 2017
13. Comparison of immunomagnetic separation beads for detection of six non-O157 Shiga toxin-producing Escherichia coli serogroups in different matrices
- Author
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David W. Lacher, Autumn L. Kraft, Julie S. Sherwood, Teresa M. Bergholz, and Weilin L. Shelver
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0301 basic medicine ,Food Safety ,Meat ,030106 microbiology ,Biology ,Serogroup ,Immunomagnetic separation ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Non o157 ,Microbiology ,law.invention ,Feces ,03 medical and health sciences ,law ,Multiplex polymerase chain reaction ,medicine ,Animals ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Polymerase chain reaction ,Complex matrix ,Shiga-Toxigenic Escherichia coli ,Immunomagnetic Separation ,Phosphate buffered saline ,Lettuce ,United States ,030104 developmental biology ,Food Microbiology ,Cattle ,Multiplex Polymerase Chain Reaction - Abstract
Immunomagnetic separation used with culture based methods has been a useful technique in the detection of pathogens. However, previous studies have not answered many of the necessary questions for real world applications. The objective of this study was to assess the efficacy of different immunomagnetic separation (IMS) bead types in recovery of the correct serogroup from a mixture of big six non-O157 Shiga toxin-producing Escherichia coli strains. To determine the impact of different matrices on recovery, samples of sterile phosphate buffered saline (PBS), sterile and non-sterile cattle faeces, ground beef and lettuce were inoculated with 10 CFU per ml mixture of isolates representing the six serogroups. After a 6 h incubation at 37°C, samples were mixed with IMS beads from three different commercial sources and plated on eosin methylene blue agar (EMB). Three suspect E. coli colonies were selected from each EMB plate and multiplex polymerase chain reaction was used to determine the serogroup. The rate of correct identification varied with the serogroup, IMS bead manufacturer and matrix. Overall, recovery of the correct serogroup became less likely with increase in matrix complexity, with enrichments containing lettuce having the greatest number of bead types with significantly lower likelihood of correct recovery compared to recovery in PBS. Significance and Impact of the Study The need to accurately and efficiently detect Shiga toxin-producing Escherichia coli (STEC) O26, O45, O103, O111, O121 and O145, which have caused outbreaks on numerous occasions, is a major public health and food safety concern in the United States. Detecting these STEC serogroups can be challenging because methods to detect non-O157 serogroups have not been refined as compared to those for O157. Immunomagnetic separation (IMS) has the potential to isolate STEC from a mixture in complex matrices. Our results highlight the need for optimization of IMS-based detection of STEC to effectively recover the targeted serogroup from a variety of sample matrices.
- Published
- 2017
14. Evaluating the efficacy of beef slaughter line interventions by quantifying the six major non-O157 Shiga toxin producing Escherichia coli serogroups using real-time multiplex PCR
- Author
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Barbara H. Ingham, Dörte Döpfer, Andrew L. Milkowski, Kelly S. Anklam, Catherine M. Fick, Megan Kulow, Kaushi S. T. Kanankege, and Charles W. Kaspar
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0301 basic medicine ,Veterinary medicine ,030106 microbiology ,Colony Count, Microbial ,Pasteurization ,Food Contamination ,Biology ,Serogroup ,Microbiology ,Non o157 ,law.invention ,Feces ,03 medical and health sciences ,fluids and secretions ,law ,Multiplex polymerase chain reaction ,Animals ,Shiga toxin-producing Escherichia coli ,Shiga-Toxigenic Escherichia coli ,Escherichia coli Proteins ,Raw beef ,food and beverages ,Contamination ,United States ,Red Meat ,030104 developmental biology ,Food Microbiology ,Cattle ,Multiplex Polymerase Chain Reaction ,Abattoirs ,Food Science - Abstract
Six major Shiga toxin producing Escherichia coli (STEC) serogroups: O26, O103, O145, O111, O121, and O45 have been declared as adulterants in federally inspected raw beef in the USA effective June 4th, 2012 in addition to the routinely tested STEC O157: H7. This study tests a real-time multiplex PCR assay and pooling of the samples to optimize the detection and quantification (prevalence and contamination) of six major non-O157 STEC, regardless of possessing Shiga toxins. To demonstrate the practicality, one large-scale slaughter plant (Plant LS) and one small-scale slaughter plant (Plant SS) located in the Mid-Western USA were sampled, in 2011, before the establishment of 2013 USDA laboratory protocols. Carcasses were sampled at consecutive intervention stations and beef trimmings were collected at the end of the fabrication process. Plant SS had marginally more contaminated samples than Plant LS (p-value 0.08). The post-hide removal wash, steam pasteurization, and lactic acid (≤5%) spray used in Plant LS seemed to reduce the six serogroups effectively, compared to the hot-water wash and 7-day chilling at Plant SS. Compared to the culture isolation methods, quantification of the non-O157 STEC using real-time PCR may be an efficient way to monitor the efficacy of slaughter line interventions.
- Published
- 2017
15. Quantifying the reduction in potential infection risks from non-O157 Shiga toxin producing Escherichia coli in strawberries by low dose electron beam processing
- Author
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Kristina D. Mena, Suresh D. Pillai, and Shima Shayanfar
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0301 basic medicine ,Serotype ,Infection risk ,010308 nuclear & particles physics ,030106 microbiology ,Low dose ,Biology ,Contamination ,01 natural sciences ,Non o157 ,Dose uniformity ,Microbiology ,03 medical and health sciences ,Microbial risk ,0103 physical sciences ,Food science ,Shiga toxin-producing Escherichia coli ,Food Science ,Biotechnology - Abstract
Strawberries are vulnerable to harboring microbial pathogens because they are generally not washed due to their perishable nature. The focus of this study was to quantify the reduction in infection risks associated with non-O157 Shiga toxin producing Escherichia coli serotypes contaminated strawberries if the strawberries are exposed to low doses ∼1 kGy (kiloGray) of electron beam (eBeam) irradiation. A cocktail of six serotypes of non O157 E. coli namely, O26:H11, O45:H2, O103:H2, O111:NM, O121:H19, and O145 was employed. Strawberry puree rather than whole strawberries were used in this study to ensure dose uniformity that is critical for accurate interpretation of microbial reduction. The results show that when these serotypes are exposed to ≤1 kGy eBeam dose, there is approximately 4-log reduction in their numbers when they are present within a strawberry matrix (puree). Quantitative microbial risk assessments suggest that if a typical strawberry serving (150 g) was heavily contaminated (∼105 CFU/serving size), 2 out of 10 susceptible individuals (20%) would get sick (without eBeam treatment). However, if these contaminated strawberries had been treated with 1 kGy of eBeam dose, the infection risks would have be significantly reduced to approximately 4 out of every 100,000 individuals (0.004%). Similarly, even at low levels of contamination (∼102 CFU/serving), the infection risks would be reduced from 6 out of 10,000 susceptible individuals to approximately 4 out of 100 million susceptible individuals.
- Published
- 2017
16. Independent Validation for the Polyskope 1.0 Multiplex Pathogen Detection Assay for the Detection of Shiga Toxin-Producing Escherichia coli Non-O157 STEC, Escherichia coli O157, Listeria monocytogenes, and Salmonella Species
- Author
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Paul Simon Smith, Leo Horine, James Agin, David Goins, Patrick Bird, Michael Benjamin Centola, Benjamin Bastin, and M Joseph Benzinger
- Subjects
Analyte ,Turkey ,Biology ,medicine.disease_cause ,Escherichia coli O157 ,Real-Time Polymerase Chain Reaction ,Non o157 ,Poultry ,Analytical Chemistry ,Listeria monocytogenes ,Salmonella ,Spinacia oleracea ,medicine ,Environmental Chemistry ,Animals ,Multiplex ,Food science ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Pharmacology ,Salmonella species ,Shiga-Toxigenic Escherichia coli ,business.industry ,Reproducibility of Results ,Food safety ,Stainless Steel ,Red Meat ,Food Microbiology ,Cattle ,business ,Agronomy and Crop Science ,Multiplex Polymerase Chain Reaction ,Food Science - Abstract
Background: The Polyskope 1.0 Multiplex Assay is a novel test to simultaneously detect Escherichia coli O157, non-O157 Shiga Toxin-Producing E. coli (STEC), Listeria monocytogenes, and Salmonella species in a single enrichment using real-time PCR. Objective: A Performance Tested MethodSM study was conducted to validate Polyskope 1.0 for inclusivity and exclusivity as well as a matrix comparison study. Method: This assay was evaluated in an unpaired independent validation study compared with reference methods according to AOAC INTERNATIONAL validation guidelines. Polyskope 1.0 evaluated raw ground beef (25 g), deli turkey (25 g), baby spinach (25 g), and stainless-steel environmental surface sponges (4 × 4 in. test area) after inoculation with a suspension of the three target microorganisms. All matrices were compared with appropriate reference methods from the U.S. Food and Drug Administration Bacteriological Analytical Manual, U.S. Department of Agriculture Food Safety and Inspection Service Microbiology Laboratory Guidebook, or International Organization for Standardization standards. Results: Polyskope 1.0 demonstrated no statistically significant differences between candidate and reference method results or between presumptive and confirmed results for three food matrices and one environmental surface. Results from inclusivity and exclusivity evaluations indicated the test method can accurately detect the target analytes and excluded all nontarget organisms. No differences were observed with the stability or lot-to-lot evaluations. Polyskope 1.0 demonstrated robustness by remaining unaffected by small variations in method parameters, which had no statistically significant effect on the results for all eight variations. Conclusions and Highlights: Polyskope 1.0 was shown to be a specific, highly accurate, and robust method for the detection of Listeria monocytogenes, Salmonella species, non-O157 STECs, and E. coli O157 across four matrices.
- Published
- 2019
17. Interrogation of single nucleotide polymorphisms in gnd provides a novel method for molecular serogrouping of clinically important Shiga toxin producing Escherichia coli (STEC) targeted by regulation in the United States, including the 'big six' non-O157 STEC and STEC O157
- Author
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J.R. Elder, H.C. den Bakker, Marie Bugarel, Guy H. Loneragan, and Kendra K. Nightingale
- Subjects
0301 basic medicine ,Microbiology (medical) ,Meat ,Genotype ,030106 microbiology ,Single-nucleotide polymorphism ,Biology ,Escherichia coli O157 ,Serogroup ,medicine.disease_cause ,Polymorphism, Single Nucleotide ,Microbiology ,Non o157 ,Feces ,03 medical and health sciences ,fluids and secretions ,Data sequences ,medicine ,Animals ,Humans ,SNP ,Multiplex ,Typing ,Serotyping ,Molecular Biology ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Escherichia coli Infections ,Genetics ,Shiga-Toxigenic Escherichia coli ,Escherichia coli Proteins ,O Antigens ,bacterial infections and mycoses ,United States ,High-Throughput Screening Assays ,Molecular Typing ,030104 developmental biology ,bacteria - Abstract
Escherichia coli O157:H7 has frequently been associated with foodborne infections and is considered an adulterant in raw non-intact beef in the U.S. Shiga toxin-producing E. coli (STEC) belonging to serogroups O26, O45, O103, O111, O121, and O145 (known as the “big six” non-O157) were estimated to cause > 70% of foodborne infections attributed to non-O157 serogroups in the U.S., as a result, these six serogroups have also been targeted by regulation in the U.S. The purpose of this study was to develop a rapid and high-throughput molecular method to group STEC isolates into seven clinically important serogroups (i.e., O157 and the “big six” non-O157 serogroups) targeted by regulation in the U.S. by interrogating single nucleotide polymorphisms (SNPs) in gnd. A collection of 195 STEC isolates, including isolates belonging to O157:H7 (n = 18), O26 (n = 21), O45 (n = 19), O103 (n = 24), O111 (n = 24), O121 (n = 23), O145 (n = 21), and ten other STEC serogroups (n = 45), was assembled and characterized by full gnd sequencing to identify informative SNPs for molecular serogrouping. A multiplex SNP typing assay was developed to interrogate twelve informative gnd SNPs by single base pair extension chemistry and used to characterize the STEC isolate collection assembled here. SNP types were assigned to each isolate by the assay and polymorphisms were confirmed with gnd sequence data. O-serogroup-specific SNP types were identified for each of the seven clinically important STEC serogroups, which allowed the differentiation of these seven STEC serogroups from other non-O157 STEC serogroups. Although serogroups of the “big six” non-O157 STEC and O157:H7 contained multiple SNP types per O-serogroup, there were no overlapping SNP types between serogroups. Our results demonstrate that molecular serogrouping of STEC isolates by interrogation of informative SNPs in gnd represents an alternative to traditional serogrouping by agglutination for rapid and high-throughput identification of clinically important STEC serogroups targeted by regulation for surveillance and epidemiological investigations.
- Published
- 2016
18. Prevalence and Characterization of Shiga Toxin-Producing Escherichia coli Isolated from Slaughtered Qurban Animal in Jakarta Province
- Author
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I.W.T. Wibawan, Retno Damayanti Soejoedono, Siti Gusti Ningrum, Wyanda Arnafia, and Hadri Latif
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0301 basic medicine ,Potential risk ,antimicrobial ,Erythromycin ,multiplex PCR ,Biology ,Antimicrobial ,Non o157 ,Microbiology ,STEC ,meat ,03 medical and health sciences ,fluids and secretions ,030104 developmental biology ,Antibiotic resistance ,feces ,Multiplex polymerase chain reaction ,medicine ,Animal Science and Zoology ,lcsh:Animal culture ,Shiga toxin-producing Escherichia coli ,Feces ,lcsh:SF1-1100 ,medicine.drug - Abstract
This study was conducted to investigate the presence of shiga toxin producing Escherichia coli (STEC) and the possibility of carrying rfbE gene and H7 flagellar on meat, liver, and stool samples collected from Jakarta Province of Indonesia. A total of 51 samples collected from meat, liver, and stool of slaughtered cattle from qurban festival were tested using conventional culture and multiplex PCR methods. STEC non O157 were detected in meat (5.3%) and stool (8.3%) with one isolate from stool carried H7 flagellar. However, all isolates were lacking of rfbE gene. In antimicrobial susceptibility tests, the STEC isolates showed antibiotic resistance to erythromycin and oxacillin. Overall, the result shows that meat and liver of this origin activity represents a potential risk to human health.
- Published
- 2016
19. Assessment of commercial chromogenic solid media for the detection of non-O157 Shiga toxin-producing Escherichia coli (STEC)
- Author
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Nathan Zelyas, Laura Patterson-Fortin, Winki Lee, Roger P. Johnson, Alan Poon, and Linda Chui
- Subjects
0301 basic medicine ,Microbiology (medical) ,food.ingredient ,animal diseases ,030106 microbiology ,Microbial Sensitivity Tests ,Biology ,medicine.disease_cause ,Sensitivity and Specificity ,Non o157 ,Microbiology ,03 medical and health sciences ,fluids and secretions ,food ,Predictive Value of Tests ,medicine ,Humans ,Agar ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Escherichia coli Infections ,Bacteriological Techniques ,Shiga-Toxigenic Escherichia coli ,Chromogenic ,General Medicine ,equipment and supplies ,bacterial infections and mycoses ,Predictive value ,Solid medium ,Anti-Bacterial Agents ,Culture Media ,Mucoid stool ,Infectious Diseases ,Chromogenic Compounds ,bacteria ,Tellurium - Abstract
Detection of Shiga toxin-producing Escherichia coli (STEC) has evolved significantly since the introduction of sorbitol-MacConkey agar. This study compares four chromogenic media (CHROMagar™ STEC, Rainbow® O157 agar, CHROMagar™ O157, and Colorex® O157) in their identification of non-O157 STEC. When 161 non-O157 STEC were directly inoculated onto each medium, detection rates on CHROMagar™ STEC, Rainbow® O157 agar, CHROMagar™ O157 and Colorex® O157 were 90%, 70%, 3.7% and 6.8%, respectively. Tellurite minimal inhibitory concentrations (MICs) correlated with growth on CHROMagar™ STEC as 20 of 22 isolates with poor or no growth had MICs ≤1μg/mL. Stool spiking experiments revealed that CHROMagar™ STEC had the highest recovery of the six most common non-O157 STEC, ranging from 30% (in mucoid stool) to 98% (in watery stool). When using clinical stool samples, CHROMagar™ STEC had a sensitivity, specificity, positive predictive value, and negative predictive value of 84.6%, 87%, 13.9%, and 99.6%, respectively.
- Published
- 2016
20. Acid Resistance of Non-O157 Shiga Toxin-Producing Escherichia coli Adapted in Fruit Juices in Simulated Gastric Fluid
- Author
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Gwang-Hee Kim and Deog-Hwan Oh
- Subjects
0301 basic medicine ,03 medical and health sciences ,Nutrition and Dietetics ,Gastric fluid ,Chemistry ,030106 microbiology ,Acid resistance ,Glutamic acid ,Food science ,Shiga toxin-producing Escherichia coli ,Non o157 ,Food Science ,Microbiology - Published
- 2016
21. Occurrence of non-O157 Shiga toxin-producing Escherichia coli in two commercial swine farms in the Eastern Cape Province, South Africa
- Author
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Larry Chikwelu Obi, Anthony I. Okoh, Benson Chuks Iweriebor, and Chinwe Juliana Iwu
- Subjects
0301 basic medicine ,Veterinary medicine ,Livestock ,Swine ,030106 microbiology ,Immunology ,Virulence ,Biology ,Escherichia coli O157 ,Serogroup ,Shiga Toxin 1 ,medicine.disease_cause ,Shiga Toxin 2 ,Microbiology ,Non o157 ,Feces ,Hemolysin Proteins ,South Africa ,03 medical and health sciences ,fluids and secretions ,STX2 ,Cape ,medicine ,Animals ,Humans ,Immunology and Allergy ,Adhesins, Bacterial ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Escherichia coli Infections ,Swine Diseases ,Shiga-Toxigenic Escherichia coli ,General Veterinary ,business.industry ,Escherichia coli Proteins ,General Medicine ,bacterial infections and mycoses ,030104 developmental biology ,Infectious Diseases ,bacteria ,Cattle ,business - Abstract
Shiga toxin-producing Escherichia coli (STEC) is one of the most significant causes of food-borne infections capable of causing serious health complications in humans. Even though ruminants are known to be the major reservoirs of STEC, other non-ruminant food producing animals may also harbour pathogenic E. coli strains. In this study, we investigated the prevalence of E. coli serogroups O26, O111, O121, O145, and O157 and their associated virulence genes (stx1, stx2, eae, and ehxA) in swine faecal samples obtained from the two major commercial farms located in the Nkonkobe Municipality, Eastern Cape, South Africa. The proportions of serogroups detected were O26; 35 (7%), O145; 14 (2.8%), and O157:H7; 43 (8.6%) of the total animals sampled. Out of the 500 animals sampled, 22 isolates of E. coli (1.4%) tested positive for the stx2 gene, and 7 of these isolates belonged to E. coli O26 serogroup, while the remaining 15 most likely belonged to serogroups untargeted in this study. Other virulence genes (stx1, eae, and ehxA) that we screened for were not detected. These findings reveal that pigs within the Eastern Cape Province of South Africa can harbour Shiga toxin-producing E. coli.
- Published
- 2016
22. Seasonal prevalence of potentially positive non-O157 Shiga toxin-producing Escherichia coli (STEC) bovine hides and carcasses in Costa Rica
- Author
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Alejandro Echeverry, Lyda G. Garcia, Markus F. Miller, Mindy M. Brashears, Todd Brashears, and Byron D. Chaves
- Subjects
Costa Rica ,Wet season ,Veterinary medicine ,business.industry ,food and beverages ,Domestic consumption ,Biology ,Shiga Toxins ,bacterial infections and mycoses ,medicine.disease_cause ,Non o157 ,Biotechnology ,fluids and secretions ,Dry season ,Escherichia coli ,medicine ,Animals ,Cattle ,Seasons ,business ,Shiga toxin-producing Escherichia coli ,Abattoirs ,Skin ,Food Science - Abstract
The prevalence of potentially positive Shiga toxin-producing Escherichia coli (STEC) bovine hides and carcasses in three abattoirs in Costa Rica was estimated. Two export facilities (A and B) and one non-export establishment (C) were visited during the dry and rainy seasons of 2013. Swabs of hides pre-eviscerated and treated (180–220 peroxyacetic acid spray) carcasses were tested for the potential presence of STEC serogroups O26, O45, O103, O111, O121, and O145. The prevalence on hides during the rainy season was 86.7, 96.7 and 96.7% for facilities A, B, and C, respectively. During the dry season, the prevalence on hides was significantly lower in plants A and B (40% and 26.7%, respectively), but was marginally associated with the season in plant C (76.7%, P = 0.0523). The prevalence of non-O157 STEC markers on treated carcasses was low (0 to 3.3%), suggesting that all plants were effective in minimizing the target non-O157 STEC in beef destined for export and for domestic consumption.
- Published
- 2015
23. Non-O157 Shiga toxin-producing Escherichia coli-A poorly appreciated enteric pathogen: Systematic review
- Author
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Saad Sidiq, Herbert L. DuPont, Alison Ramsey, and Evangelia M. Valilis
- Subjects
0301 basic medicine ,Microbiology (medical) ,Adult ,Diarrhea ,030106 microbiology ,Enteric pathogen ,H antigen ,medicine.disease_cause ,Serogroup ,Non o157 ,lcsh:Infectious and parasitic diseases ,Disease Outbreaks ,03 medical and health sciences ,fluids and secretions ,Medicine ,Humans ,lcsh:RC109-216 ,Epidemic disease ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Escherichia coli Infections ,Shiga-Toxigenic Escherichia coli ,business.industry ,Dysentery ,Outbreak ,General Medicine ,medicine.disease ,Virology ,030104 developmental biology ,Infectious Diseases ,Hemolytic-Uremic Syndrome ,business - Abstract
Non-O157 strains of Shiga toxin-producing Escherichia coli (STEC) are more common causes of acute diarrhea than the better-known O157 strains and have the potential for large outbreaks. This systematic review of the literature identified 129 serogroups as well as 262 different O and H antigen combinations of STEC in cases of epidemic and sporadic disease worldwide. Excluding the results from a single large outbreak of STEC O104:H4 in Germany and France in 2011, the reported frequency of dysenteric illness in patients was 26% (119 of 464) for epidemic disease and 25% (646 of 2588) for sporadic cases. Hemolytic uremic syndrome was identified in 14% of epidemic disease cases and 9% of sporadic illness cases. With the increasing use of PCR-based diagnostics, STEC strain identification may not be possible. Rapid diagnostics are needed for STEC infections to aid the clinician while allowing epidemiologists the opportunity to identify outbreaks and to trace the source of infection. Keywords: Shigatoxin producing E. coli, hemolytic uremic syndrome, dysentery
- Published
- 2018
24. Comparison of the Diatheva STEC FLUO with BAX System Kits for Detection of O157:H7 and Non-O157 Shiga Toxin-Producing Escherichia coli (STEC) in Ground Beef and Bean Sprout Samples Using Different Enrichment Protocols
- Author
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Giulia Amagliani, Enrica Omiccioli, Pina M. Fratamico, Luca Rotundo, Elisa Carloni, and Mauro Magnani
- Subjects
0301 basic medicine ,Mung bean ,Inoculation ,030106 microbiology ,Pcr assay ,Cefsulodin ,Biology ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Non o157 ,Analytical Chemistry ,Shiga toxin-producing E. coli . Real-time PCR . Ground beef . Bean sprouts ,03 medical and health sciences ,fluids and secretions ,030104 developmental biology ,STX2 ,medicine ,bacteria ,Food science ,Safety, Risk, Reliability and Quality ,Safety Research ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Food Science ,medicine.drug - Abstract
The aim of this study was to assess the performance of the Diatheva STEC FLUO and BAX System real-time PCR assays for detection of Shiga toxin-producing Escherichia coli (STEC) (stx1/stx2 and eae target genes) and O-group identification in ground beef and bean sprout samples. Ground beef (325 g or 25 g) and mung bean sprout (25 g) samples were inoculated with ~ 10 CFU of the “top five” STEC (O157:H7, O26, O103, O111, and O145 as specified in EU regulation ISO13136:2012), enriched using different broths and incubation temperatures, and tested using the Diatheva and BAX real-time PCR assays. In ground beef, both molecular methods were able to detect the “top five” STEC, and lower Ct values were observed for the Diatheva kits compared to BAX System. The O111-contaminated samples gave negative results with both methods using mTSB + novobiocin for enrichment. In bean sprouts, both methods provided positive results, although detection was not possible using mTSB + acriflavin/cefsulodin/vancomycin for enrichment. In conclusion, the Diatheva and BAX methods detected the “top five” STEC in ground beef and bean sprouts when inoculated at low levels. Both assays provided equivalent results in terms of performance and reliability. Thus, the Diatheva kits are comparable to reference STEC-detection methods and could be used by the food industry to reliably detect the “top five” STEC.
- Published
- 2018
25. Comparison of the RAPID-B® flow cytometer and the BAX® system for the detection of non-O157 shiga toxin-producing Escherichia coli (STEC) in beef products
- Author
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Peggy Cook, Christopher A. Baker, Steven C. Ricke, Karen Beers, Shawn Ramsaroop, Si Hong Park, Melinda Miller, John Ferguson, and David Caldwell
- Subjects
Beef industry ,Chromatography ,Chemistry ,Screening Result ,Whole cell ,Shiga toxin-producing Escherichia coli ,Rapid detection ,Non o157 ,Food Science ,Biotechnology ,Microbiology - Abstract
The beef industry continues to be interested in reliable rapid detection technologies for shiga toxin-producing Escherichia coli (STEC). Current rapid technologies require several hours of pre-enrichment and additional time on the rapid technology instrument. A flow cytometer-based system (RAPID-B®) has been shown to improve the turn-around for results with a more rapid pre-enrichment requiring only 6.5 h pre-enrichment for a 25 g and 8.5 h for a 375 g sample, followed by an additional 30 min time to achieve final results using the screening technology. The purpose of this study was to validate the RAPID-B® technology for non-O157 STEC detection as compared to the USDA-FSIS reference method which utilizes the BAX® system. A total of 180 STEC isolates from various sources and 20 non-STEC strains were used to evaluate specificity and sensitivity using the RAPID-B® flow cytometer. Also, three different weights (25, 325 and 375 g) of beef trim and ground beef samples were spiked with each STEC to verify detection sensitivity of BAX® system and RAPID-B® flow cytometer. For both methods, samples were confirmed by culturing using the USDA-FSIS reference method regardless of the screening result. The RAPID-B® flow cytometer showed that 180 isolates were all positive and the 20 non-STEC strains were all negative. For spiked beef samples, overall detection sensitivity was the same for both the BAX® system and RAPID-B® flow cytometer. When detection sensitivity was based on sample weight, there was no differences in 25 and 375 g samples between RAPID-B® flow cytometer and USDA-FSIS reference method. The RAPID-B® system yielded the same sensitivity as the reference method with a decrease of over 10 h of pre-enrichment time and 3 h of rapid screening detection time. In conclusion, the RAPID-B® flow cytometer based on whole cell detection generated similar results as BAX® system therefore the RAPID-B® flow cytometer system could be a valuable rapid method for the detection of non-O157 STEC in beef products.
- Published
- 2015
26. Isolation and characterization of non-O157 Shiga toxin-producing Escherichia coli from beef carcasses, cuts and trimmings of abattoirs in Argentina
- Author
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Germán Suberbie, Hebe Brasesco, Marcelo E. Sanz, Victoria Brusa, David Teitelbaum, Viviana Restovich, Valeria Superno, Marcelo Signorini, Marcela Ferreghini, Magdalena Costa, Alejandra Londero, Diego García, Ricardo Rodríguez, Sandra Petroli, Gerardo Anibal Leotta, Nora Lía Padola, Luciano Héctor Linares, Lucía Galli, Adriana Sucari, and Mariana Bruzzone
- Subjects
0301 basic medicine ,Serotype ,Bacterial Diseases ,Veterinary medicine ,lcsh:Medicine ,Carne de Res ,Pathology and Laboratory Medicine ,Non o157 ,Geographical locations ,purl.org/becyt/ford/1 [https] ,fluids and secretions ,Intervention measures ,Animal Products ,Medicine and Health Sciences ,Toxins ,lcsh:Science ,media_common ,Mammals ,Aislamiento ,Multidisciplinary ,MEAT ,Shiga-Toxigenic Escherichia coli ,Monitoring system ,Shiga toxin ,Agriculture ,Heart ,Ruminants ,Gene Pool ,Bioquímica y Biología Molecular ,Isolation (microbiology) ,Electrophoresis, Gel, Pulsed-Field ,Mataderos ,Serología ,STEC ,Infectious Diseases ,Serology ,Vertebrates ,Anatomy ,Pathogens ,Beef ,CIENCIAS NATURALES Y EXACTAS ,Abattoirs ,Research Article ,Meat ,Virulence Factors ,030106 microbiology ,Argentina ,Biology ,Isolation ,Ciencias Biológicas ,03 medical and health sciences ,Animal science ,Bovines ,SLAUGHTERHOUSE ,Genetics ,Escherichia coli ,media_common.cataloged_instance ,Animals ,QUALITY ,European union ,purl.org/becyt/ford/1.6 [https] ,Shiga toxin-producing Escherichia coli ,Nutrition ,Evolutionary Biology ,Population Biology ,Ciencias Veterinarias ,lcsh:R ,Organisms ,Biology and Life Sciences ,South America ,Genética ,Diet ,030104 developmental biology ,Food ,Genes, Bacterial ,Amniotes ,Hemolytic-Uremic Syndrome ,biology.protein ,Cardiovascular Anatomy ,bacteria ,Toxinas ,lcsh:Q ,Cattle ,People and places ,Population Genetics - Abstract
Several foods contaminated with Shiga toxin-producing Escherichia coli (STEC) are associated with human diseases. Some countries have established microbiological criteria for non-O157 STEC, thus, the absence of serogroups O26, O45, O103, O104, O111, O121, and O145 in sprouts from the European Union or ground beef and beef trimmings from the United States is mandatory. While in Argentina screening for O26, O103, O111, O145 and O121 in ground beef, ready-to-eat food, sausages and vegetables is mandatory, other countries have zero-tolerance for all STEC in chilled beef. The aim of this study was to provide data on the prevalence of non-O157 STEC isolated from beef processed in eight Argentinean cattle slaughterhouses producing beef for export and local markets, and to know the non-O157 STEC profiles through strain characterization and genotypic analysis. Samples (n = 15,965) from 3,205 beef carcasses, 9,570 cuts and 3,190 trimmings collected between March and September 2014 were processed in pools of five samples each. Pools of samples (n = 3,193) from 641 carcasses, 1,914 cuts and 638 trimming were analyzed for non-O157 STEC isolation according to ISO/CEN 13136:2012. Of these, 37 pools of carcasses (5.8%), 111 pools of cuts (5.8%) and 45 pools of trimmings (7.0%) were positive for non-O157 STEC. STEC strains (n = 200) were isolated from 193 pools of samples. The most prevalent serotypes were O174:H21, O185:H7, O8:H19, O178:H19 and O130:H11, and the most prevalent genotypes were stx2c(vh-b) and stx2a/saa/ehxA. O103:H21 strain was eae-positive and one O178:H19 strain was aggR/aaiC-positive. The prevalence of non-O157 STEC in beef carcasses reported here was low. None of the non-O157 STEC strains isolated corresponded to the non-O157 STEC serotypes and virulence profiles isolated from human cases in Argentina in the same study period. The application of microbiological criteria for each foodstuff should be determined by risk analysis in order to have a stringent monitoring system. Likewise, zero-tolerance intervention measures should be applied in beef, together with GMP and HACCP. Further, collaborative efforts for risk assessment, management and communication are extremely important to improve the safety of foodstuffs., Instituto de Genética Veterinaria, Facultad de Ciencias Veterinarias
- Published
- 2017
27. Persistence and reduction of Shiga toxin-producing Escherichia coli serotype O26:H11 in different types of raw fermented sausages
- Author
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Christina Böhnlein, Gregor Fiedler, Charles M. A. P. Franz, Jan Kabisch, Stefanie Müller-Herbst, and Rohtraud Pichner
- Subjects
0301 basic medicine ,Serotype ,030106 microbiology ,Food Contamination ,Biology ,medicine.disease_cause ,Serogroup ,Microbiology ,Non o157 ,Persistence (computer science) ,Disease Outbreaks ,Shiga Toxin ,03 medical and health sciences ,fluids and secretions ,medicine ,Animals ,Humans ,Food science ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Escherichia coli Infections ,Shiga-Toxigenic Escherichia coli ,Inoculation ,food and beverages ,Outbreak ,General Medicine ,biochemical phenomena, metabolism, and nutrition ,bacterial infections and mycoses ,Europe ,Meat Products ,030104 developmental biology ,Fermentation ,bacteria ,Food Science - Abstract
Fermented sausages have been identified as source of several outbreaks of Shiga toxin-producing Escherichia coli (STEC). Illnesses linked to non-O157 STEC serotypes appear to be on the rise worldwide, and serogroup O26 is the second most reported in Europe after O157. However, data on the behavior of serogroup O26 in food are rare, so that the aim of this study was to investigate the survival of STEC O26:H11 in different types of fermented sausages (“Teewurst”, fast-ripened and long-fermented salami). Challenge studies were performed with an inoculation cocktail which consisted of three STEC O26:H11 strains isolated from human, cattle and food sources. In the short-ripened spreadable sausage type “Teewurst” STEC counts decreased by only 0.5 log10 within 28 days. In contrast, STEC reductions from 2.2 to 2.6 log10 units were observed in the different salami products, while the most pronounced decrease of 1.0 log10 unit within one day was detected in fast-ripened sausages with glucono delta-lactone (GdL). Moreover, numbers of the food-associated E. coli O26:H11 strain were significantly higher (p
- Published
- 2017
28. Growth of Strains of the Major Non-O157 Shiga Toxin–Producing Escherichia coli Serogroups Is Not Different from Growth of Escherichia coli O157:H7 in Neutral Broth (pH 7.4) and Acidified Broth (pH 5.6) at 10°C
- Author
-
Steve C. Ingham, K. Chatzikyriakidou, Barbara H. Ingham, and Renae R Geier
- Subjects
Meat ,Biology ,Escherichia coli O157 ,Serogroup ,medicine.disease_cause ,Microbiology ,Single strain ,Non o157 ,chemistry.chemical_compound ,fluids and secretions ,medicine ,Humans ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Shiga-Toxigenic Escherichia coli ,Strain (chemistry) ,Inoculation ,Significant difference ,Temperature ,Hydrogen-Ion Concentration ,bacterial infections and mycoses ,Culture Media ,Lactic acid ,chemistry ,bacteria ,Food Science - Abstract
Understanding the survival and growth of non-O157 Shiga toxin-producing Escherichia coli (STEC) strains under cold temperatures may be important for protecting public health. The aim of this study was to compare the growth of three strains of each of the major non-O157 STEC serogroups (O26, O45, O103, O111, O121, and O145) with the growth of six O157:H7 STEC strains in broth at 10°C. Brain heart infusion broth (BHIB; pH 7.4) was inoculated with a single strain of stationary-phase STEC culture to produce a starting inoculum of ∼10(6) CFU/ml and stored at 10°C for up to 96 h (three trials per strain). Populations over time were fitted to the Baranyi and Roberts model, and lag-phase duration (LPD) and growth rate were calculated for each strain per trial. Average LPD ranged from 9.2 to 32.8 h for non-O157 STEC and from 10.5 to 17.2 h for O157 STEC. One strain of O26 STEC had a significantly longer LPD (P0.05) than did the other strains (32.8 h); otherwise, no significant differences were noted (P0.05). Growth rate ranged from 0.031 to 0.060 log CFU/ml/h for non-O157 STEC strains and from 0.034 to 0.046 log CFU/ml/h for O157 STEC strains. No significant difference in growth rate was noted among strains in BHIB at pH 7.4 and 10°C. In subsequent trials, growth of a single strain of each of the non-O157 STEC serogroups was compared with growth of four acid-tolerant O157 STEC strains in BHIB acidified to pH 5.6 with lactic acid. Acidification generally increased LPD and decreased the growth rate for strains, although the effect was variable and not significant. These findings suggest that growth patterns for strains of non-O157 STEC are similar to those for strains of O157 STEC in neutral and pH 5.6 BHIB at 10°C. Further research is needed to determine whether strains behave similarly in meat systems.
- Published
- 2014
29. Detection of Non-O157 Shiga Toxin-Producing Escherichia coli (STEC) Serogroups with Hyperspectral Microscope Imaging Technology
- Author
-
Bosoon Park, Heesung Kwon, William C. Cray, Kurt C. Lawrence, Scott R. Ladely, Prudhvi Gurram, Seung-Chul Yoon, Neelam Narang, and William R. Windham
- Subjects
Foodborne pathogen ,business.industry ,Biomedical Engineering ,Soil Science ,Hyperspectral imaging ,Forestry ,Pattern recognition ,Biology ,medicine.disease_cause ,Cell counting ,Non o157 ,Human health ,medicine ,Artificial intelligence ,business ,Agronomy and Crop Science ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Microscope imaging ,Food Science - Abstract
Non-O157 Shiga toxin-producing Escherichia coli (STEC) serogroups such as O26, O45, O103, O111, O121, and O145 are recognized as serious risks to human health due to their toxicity. The conventional microbiological detection method of cell counting on agar plates is laborious and time-consuming. Because optical methods are promising for real-time, in situ foodborne pathogen detection, a hyperspectral microscope imaging (HMI) method based on acousto-optic tunable filters (AOTF) was developed for detecting pathogenic bacteria with a capability to differentiate the spectral characteristics of each bacterial cell from microcolony samples. Using the AOTF-based HMI method, a total of 89 contiguous spectral images were acquired within approximately 45 s with 250 ms exposure time. In this study, we developed a protocol for successfully immobilizing live cells on glass slides to acquire quality spectral images of STEC bacterial cells using a modified drying method. Among the contiguous spectral imagery between 450 and 800 nm, the intensities at 458, 498, 522, 546, 570, 586, 670, and 690 nm were distinct for STEC bacteria under dark-field illumination. With two different classification algorithms, i.e., support vector machine (SVM) and sparse kernel-based ensemble learning (SKEL), STEC serogroup O45 could be classified with 92% detection accuracy. However, the mean accuracies in identifying the six STEC serogroups with SVM and SKEL were not high enough for use in classification models.
- Published
- 2014
30. Non-O157 Shiga Toxin-Producing Escherichia coli in U.S. Retail Ground Beef
- Author
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Yen-Te Liao, Guy H. Loneragan, Markus F. Miller, Alejandro Echeverry, Mindy M. Brashears, and J. Chance Brooks
- Subjects
Meat ,food.ingredient ,Escherichia coli Proteins ,Food Contamination ,Biology ,medicine.disease_cause ,Immunomagnetic separation ,Microbiology ,United States ,Tryptic soy broth ,Non o157 ,Latex fixation test ,chemistry.chemical_compound ,food ,chemistry ,Escherichia coli ,medicine ,Animals ,Agar ,Cattle ,Food science ,Shiga toxin-producing Escherichia coli ,Food Science ,Food contaminant - Abstract
Shiga toxin-producing Escherichia coli (STEC) serotype O157:H7 and serogroups O26, O45, O103, O111, O121, and O145 are the leading cause of STEC-associated infections in humans in the United States. In the United States, these organisms are considered adulterants in raw nonintact beef products and in intact beef destined to be made into or used in nonintact raw beef products. The objective of this study was to provide an estimate of the burden of the six serogroups of non-O157 STEC in ground beef obtained from retail stores across the United States. A convenience sample of commercial ground beef products (n = 1,129) were purchased from retail stores in 24 states from October 2011 to May 2012. The samples had various lean/fat proportions, muscle group of origin (chuck, round, sirloin, or not specified), and packaging types. For each ground beef sample, 25 g was inoculated in 225 ml of modified tryptic soy broth, stomached for 1 min, and then incubated at 41°C for 18 ± 2 h. These enrichment cultures were then screened for stx, eae, and O group genes using a commercially available, closed-platform PCR-based method. The potential positive samples were subjected to immunomagnetic separation and plated on modified Rainbow agar. Morphologically typical colonies were subjected to latex agglutination and PCR determination of stx and eae genes. Nine (0.8%) of the ground beef samples were potentially positive for at least one STEC serogroup after PCR screening. The serogroups detected by PCR assay were O26 (four samples), O103 (four samples), O145 (three samples), O45 (two samples), and O121 (one sample). No STEC isolates belonging to these serogroups were recovered from the sample cultures. The current research provides updated surveillance data for non-O157 STEC isolates among commercial ground beef products and information regarding the potential sources of contamination from different parts of beef trims destined for ground beef production.
- Published
- 2014
31. Thermal Inactivation of Escherichia coli O157:H7 and Non-O157 Shiga Toxin-Producing Escherichia coli Cells in Mechanically Tenderized Veal
- Author
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Anna C. S. Porto-Fett, Harshavardhan Thippareddi, Michael Lemler, Jesus R. Amaya, Bradley A. Shoyer, and John B. Luchansky
- Subjects
Hot Temperature ,Meat ,Sheep ,Shiga-Toxigenic Escherichia coli ,Food Handling ,Chemistry ,Colony Count, Microbial ,Temperature ,food and beverages ,Escherichia coli O157 ,medicine.disease_cause ,Microbiology ,Non o157 ,Internal temperature ,medicine ,Once through ,Animals ,Cooking ,Food science ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Food Science - Abstract
Preflattened veal cutlets (ca. 71.5 g, ca. 0.32 cm thick) were surface inoculated with ca. 6.8 log CFU/g of a multistrain cocktail of Escherichia coli O157:H7 (ECOH) or a cocktail made of single strains of serogroups O26, O45, O103, O104, O111, O121, and O145 of Shiga toxin-producing E. coli (STEC) cells and then were mechanically tenderized by passing once through a "Sir Steak" tenderizer. For each cooking time, in each of at least three trials, three inoculated and tenderized cutlets, with and without breading, were individually cooked in 15 or 30 ml of canola oil for 0.0, 0.75, 1.0, 1.25, 1.5, 1.75, or 2.25 min per side on an electric skillet set at 191.5°C. The temperatures of the meat and of the skillet were monitored and recorded using a type J thermocouple. Regardless of the breading or volume of oil used to cook the meat, the longer the cooking times, the higher was the internal temperature of the meat, along with a greater reduction of both ECOH and STEC. The average final internal temperature of the meat at the approximate geometric center ranged from 56.8 to 93.1°C. Microbial reductions of ca. 2.0 to 6.7 log CFU/g and ca. 2.6 to 6.2 log CFU/g were achieved for ECOH and STEC, respectively. Our data also revealed no differences in thermal inactivation of ECOH relative to the volume of oil used to cook nonbreaded cutlets. However, when cooking breaded cutlets, the use of more (30 ml) compared with less (15 ml) cooking oil resulted in greater reductions in pathogen numbers. To deliver about a 5.0-log reduction of ECOH and STEC, and to achieve the recommended internal temperature of 71.1°C, it was necessary to cook mechanically tenderized veal cutlets for at least 1.5 min per side on a preheated electric skillet set at 191.5°C and containing 15 ml of cooking oil. These data also established that cooking times and temperatures effective for inactivating serotype O157:H7 strains of E. coli in tenderized veal are equally effective against the additional six non-O157 Shiga toxin-producing strains investigated herein.
- Published
- 2014
32. Multiple-Aetiology Enteric Infections Involving Non-O157 Shiga Toxin-ProducingEscherichia coli- FoodNet, 2001-2010
- Author
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J. Sadlowski, H. Martin, C. Nicholson, A. Palmer, Patricia M. Griffin, R. W. Gierke, K. Garman, Carlota Medus, M. Tobin-D'Angelo, Rajal K. Mody, Ruth E. Luna-Gierke, K. Wymore, S. McGuire, and P. Clogher
- Subjects
Adult ,Male ,Adolescent ,Epidemiology ,animal diseases ,Population ,Cryptosporidiosis ,Biology ,Escherichia coli O157 ,Non o157 ,Shiga Toxin ,Microbiology ,Young Adult ,fluids and secretions ,Risk Factors ,Zoonoses ,Campylobacter Infections ,Animals ,Humans ,Child ,education ,Shiga toxin-producing Escherichia coli ,Escherichia coli Infections ,Aged ,Population survey ,Aged, 80 and over ,education.field_of_study ,Microbial toxins ,Shiga-Toxigenic Escherichia coli ,General Veterinary ,General Immunology and Microbiology ,Public Health, Environmental and Occupational Health ,Infant ,Outbreak ,Middle Aged ,bacterial infections and mycoses ,Virology ,United States ,Infectious Diseases ,Animals, Domestic ,Child, Preschool ,Population Surveillance ,Salmonella Infections ,Etiology ,bacteria ,Female - Abstract
We describe multiple-aetiology infections involving non-O157 Shiga toxin-producing Escherichia coli (STEC) identified through laboratory-based surveillance in nine FoodNet sites from 2001 to 2010. A multiple-aetiology infection (MEI) was defined as isolation of non-O157 STEC and laboratory evidence of any of the other nine pathogens under surveillance or isolation of >1 non-O157 STEC serogroup from the same person within a 7-day period. We compared exposures of patients with MEI during 2001-2010 with those of patients with single-aetiology non-O157 STEC infections (SEI) during 2008-2009 and with those of the FoodNet population from a survey conducted during 2006-2007. In total, 1870 non-O157 STEC infections were reported; 68 (3.6%) were MEI; 60 included pathogens other than non-O157 STEC; and eight involved >1 serogroup of non-O157 STEC. Of the 68 MEI, 21 (31%) were part of six outbreaks. STEC O111 was isolated in 44% of all MEI. Of patients with MEI, 50% had contact with farm animals compared with 29% (P < 0.01) of persons with SEI; this difference was driven by infections involving STEC O111. More patients with non-outbreak-associated MEI reported drinking well water (62%) than respondents in a population survey (19%) (P < 0.01). Drinking well water and having contact with animals may be important exposures for MEI, especially those involving STEC O111.
- Published
- 2014
33. Outbreaks of non-O157 Shiga toxin-producingEscherichia coliinfection: USA
- Author
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Ruth E. Luna-Gierke, Nancy Strockbine, Paul M. Griffin, L. H. Gould, Cheryl A. Bopp, Rajal K. Mody, and Karen M Herman
- Subjects
Male ,Epidemiology ,Enteric pathogen ,Escherichia coli O157 ,Shiga Toxin 1 ,medicine.disease_cause ,Risk Assessment ,Severity of Illness Index ,Non o157 ,Disease Outbreaks ,Microbiology ,medicine ,Humans ,Registries ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Escherichia coli Infections ,Shiga-Toxigenic Escherichia coli ,biology ,Incidence ,Incidence (epidemiology) ,Outbreak ,Shiga toxin ,Original Papers ,United States ,Infectious Diseases ,biology.protein ,Female ,Haemolytic-uraemic syndrome - Abstract
SUMMARYNon-O157 Shiga toxin-producingEscherichia coli(STEC) infections are increasingly detected, but sources are not well established. We summarize outbreaks to 2010 in the USA. Single-aetiology outbreaks were defined as ⩾2 epidemiologically linked culture-confirmed non-O157 STEC infections; multiple-aetiology outbreaks also had laboratory evidence of ⩾2 infections caused by another enteric pathogen. Twenty-six states reported 46 outbreaks with 1727 illnesses and 144 hospitalizations. Of 38 single-aetiology outbreaks, 66% were caused by STEC O111 (n = 14) or O26 (n = 11), and 84% were transmitted through food (n = 17) or person-to-person spread (n = 15); food vehicles included dairy products, produce, and meats; childcare centres were the most common setting for person-to-person spread. Of single-aetiology outbreaks, a greater percentage of persons infected by Shiga toxin 2-positive strains had haemolytic uraemic syndrome compared with persons infected by Shiga toxin 1-only positive strains (7%vs.0·8%). Compared with single-aetiology outbreaks, multiple-aetiology outbreaks were more frequently transmitted through water or animal contact.
- Published
- 2014
34. Hemolytic Uremic Syndrome Due to Non-O157 Shiga Toxin-Producing Escherichia coli : Possible Need for Method Improvement
- Author
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María José González-Abad and Mercedes Alonso Sanz
- Subjects
0301 basic medicine ,Microbiology (medical) ,03 medical and health sciences ,Infectious Diseases ,030106 microbiology ,Biology ,Shiga toxin-producing Escherichia coli ,Non o157 ,Microbiology - Published
- 2018
35. Evidence of Non-O157 Shiga Toxin—Producing Escherichia coli in the Feces of Meat Goats at a U.S. Slaughter Plant
- Author
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Tiruvoor G. Nagaraja, C. C. Balcomb, Derek M. Foster, Xiaorong Shi, Megan E. Jacob, and A. T. Rogers
- Subjects
DNA, Bacterial ,Serotype ,Meat ,Colony Count, Microbial ,Virulence ,Human pathogen ,Biology ,medicine.disease_cause ,Microbiology ,Non o157 ,Feces ,fluids and secretions ,Multiplex polymerase chain reaction ,Prevalence ,medicine ,Animals ,Humans ,Serotyping ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Disease Reservoirs ,Shiga-Toxigenic Escherichia coli ,Goats ,bacterial infections and mycoses ,Southeastern United States ,Food Microbiology ,bacteria ,Cattle ,Multiplex Polymerase Chain Reaction ,Abattoirs ,Food Science - Abstract
Shiga toxin-producing Escherichia coli (STEC) are important human pathogens, and attention to non-O157 serogroups has increased in recent years. Although cattle are normally considered the primary reservoir for STEC, recent illnesses associated with goat contact have indicated that these animals are important potential reservoirs for the organisms. The prevalence of STEC, particularly non-O157 serogroups, in U.S. goats has not been well described. Our objective was to determine the prevalence of six major non-O157 STEC serogroups in the feces of meat goats. Rectal contents from 296 goats were collected postevisceration at a slaughter plant in the southeastern United States over 9 days during a 12-week period from August through October 2012. Samples were enriched in E. coli broth, and DNA was extracted and used as template in an 11-gene multiplex PCR that detected six non-O157 serogroups (O26, O45, O103, O121, O111, and O145) and virulence genes. Samples were considered positive when at least one non-O157 STEC serotype was present with either stx 1 or stx 2. All six non-O157 serogroups were detected by PCR in our samples, and 14.5% of samples were positive for at least one serogroup. Prevalence of O26 was highest, with 6.4% of goat fecal samples positive. The prevalence of O45 was 3.4%, O103 was 4.4%, O111 was 4.1%, O121 was 1.4%, and O145 was 3.0%. Twenty-two (7.4%) of 296 fecal samples had more than one non-O157 serogroup detected in the feces. Two samples had evidence of three non-O157 STEC serogroups. Goats appear to be an important reservoir for non-O157 STEC, and further work to understand the characteristics, epidemiology, and ecology of STEC in these animals is warranted.
- Published
- 2013
36. Comparison between ImmunoCard STAT!® and real-time PCR as screening tools for both O157:H7 and non-O157 Shiga toxin-producing Escherichia coli in Southern Alberta, Canada
- Author
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Valerie F. Boras, Richelle Allen, Mao-Cheng Lee, Aaron Bryks, Linda Chui, and Linsey Haines
- Subjects
Adult ,Male ,Microbiology (medical) ,Adolescent ,Biology ,Real-Time Polymerase Chain Reaction ,medicine.disease_cause ,Sensitivity and Specificity ,Non o157 ,Alberta ,Microbiology ,Young Adult ,fluids and secretions ,medicine ,Humans ,Mass Screening ,Screening tool ,Child ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Escherichia coli Infections ,Aged, 80 and over ,Immunoassay ,Bacteriological Techniques ,Shiga-Toxigenic Escherichia coli ,Alberta canada ,Outbreak ,General Medicine ,Middle Aged ,Virology ,Infectious Diseases ,Real-time polymerase chain reaction ,Child, Preschool ,bacteria ,Female ,Bloody diarrhea - Abstract
An increasing number of non-O157 Shiga toxin-producing Escherichia coli (STEC) infections and outbreaks have been reported. In this study, we evaluated the performance of ImmunoCard STAT!(®) (Meridian Bioscience, Inc., Cincinnati, OH, USA) as a method to screen stool specimens for STEC (O157 and non-O157). An in-house real-time PCR method was used as the "gold standard". We also evaluated the prevalence and clinical characteristics of STEC infections in the Alberta South West Zone. From July to November 2011, 819 stool specimens submitted for routine stool culture were tested. With our in-house real-time PCR, 7 O157:H7 and 10 non-O157 STEC isolates were identified for a total of 17 STECs. In comparison, ImmunoCard STAT!(®) identified a total of 6, resulting in a sensitivity and specificity of 35% and 99%, respectively (P0.05). Because of the low sensitivity, ImmunoCard STAT!(®) cannot be recommended as a routine screening test for STEC from enriched stool specimens. The rate of STEC positivity as detected by PCR was 2.08%, of which 0.86% was O157:H7 and 1.22% non-O157 STEC. Five of the 7 cases of STEC O157 infection experienced bloody diarrhea, and 1 developed hemolytic uremic syndrome.
- Published
- 2013
37. Fate of Shiga Toxin--Producing O157:H7 and Non-O157:H7 Escherichia coli Cells within Refrigerated, Frozen, or Frozen Then Thawed Ground Beef Patties Cooked on a Commercial Open-Flame Gas or a Clamshell Electric Grill
- Author
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John G. Phillips, Emilio Esteban, Vivian Chen, Tim B. Mohr, Anna C. S. Porto-Fett, John B. Luchansky, Nathan Bauer, Denise R. Eblen, Bradley A. Shoyer, and L. Victor Cook
- Subjects
Clamshell ,Shiga-Toxigenic Escherichia coli ,Food Handling ,Chemistry ,Colony Count, Microbial ,Temperature ,Food storage ,Cold storage ,Escherichia coli O157 ,medicine.disease_cause ,Microbiology ,Non o157 ,Shiga Toxin ,Meat Products ,Shiga toxin producing ,Food Microbiology ,medicine ,Animals ,Cattle ,Cooking ,Frozen storage ,Food science ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Food Science - Abstract
Both high-fat and low-fat ground beef (percent lean:fat = ca. 70:30 and 93:7, respectively) were inoculated with a 6-strain cocktail of non-O157:H7 Shiga toxin-producing Escherichia coli (STEC) or a five-strain cocktail of E. coli O157:H7 (ca. 7.0 log CFU/g). Patties were pressed (ca. 2.54 cm thick, ca. 300 g each) and then refrigerated (4°C, 18 to 24 h), or frozen (-18°C, 3 weeks), or frozen (-18°C, 3 weeks) and then thawed (4°C for 18 h or 21°C for 10 h) before being cooked on commercial gas or electric grills to internal temperatures of 60 to 76.6°C. For E. coli O157:H7, regardless of grill type or fat level, cooking refrigerated patties to 71.1 or 76.6°C decreased E. coli O157:H7 numbers from an initial level of ca. 7.0 log CFU/g to a final level of ≤1.0 log CFU/g, whereas decreases to ca. 1.1 to 3.1 log CFU/g were observed when refrigerated patties were cooked to 60.0 or 65.5°C. For patties that were frozen or freeze-thawed and cooked to 71.1 or 76.6°C, E. coli O157:H7 numbers decreased to ca. 1.7 or ≤0.7 log CFU/g. Likewise, pathogen numbers decreased to ca. 0.7 to 3.7 log CFU/g in patties that were frozen or freeze-thawed and cooked to 60.0 or 65.5°C. For STEC, regardless of grill type or fat level, cooking refrigerated patties to 71.1 or 76.6°C decreased pathogen numbers from ca. 7.0 to ≤0.7 log CFU/g, whereas decreases to ca. 0.7 to 3.6 log CFU/g were observed when refrigerated patties were cooked to 60.0 or 65.5°C. For patties that were frozen or freeze-thawed and cooked to 71.1 or 76.6°C, STEC numbers decreased to a final level of ca. 1.5 to ≤0.7 log CFU/g. Likewise, pathogen numbers decreased from ca. 7.0 to ca. 0.8 to 4.3 log CFU/g in patties that were frozen or freeze-thawed and cooked to 60.0 or 65.5°C. Thus, cooking ground beef patties that were refrigerated, frozen, or freeze-thawed to internal temperatures of 71.1 and 76.6°C was effective for eliminating ca. 5.1 to 7.0 log CFU of E. coli O157:H7 and STEC per g.
- Published
- 2013
38. Occurrence of non-O157 Shiga toxin-producing Escherichia coli in healthy cattle and goats and distribution of virulence genes among isolates
- Author
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M. Murugaiyah, Rahim A. M, Shah A. H, TayZar A. C, and Saleha A. A
- Subjects
Virulence ,Shiga toxin ,Plant Science ,Biology ,bacterial infections and mycoses ,Microbiology ,Non o157 ,fluids and secretions ,Infectious Diseases ,STX2 ,biology.protein ,bacteria ,Shiga toxin-producing Escherichia coli ,Gene - Abstract
Shiga toxin-producing Escherichia coli (STEC) are receiving more attention mainly because they are zoonotic and food borne in nature. The objectives of the present study were to determine the occurrence of non-O157 Shiga toxin producing E. coli in cattle and goats and distribution of the virulence genes in the isolates. The overall isolation rates of non-O157 STEC was 15.27% (7/87) in cattle and 8.14% (22/144) in goats. Four serogroups namely O8, O26, O103 and O128 were detected. Of these serogroups, O8, O26 and O103 were common in both, cattle and goats, whereas O128 was carried by goats only. Using Duopath Verotoxin (DV) test, 52.63% of sero-positive E. coli isolates from cattle were positive for Stx1 shiga toxin whereas none of the isolates was positive for Stx2. Similarly, 42.9% (3/7) of sero-positive E. coli isolates from goats produced Stx1 and 14.3% (1/7) were positive for both, Stx1 and Stx2. The study on virulence genes showed that stx1 was commonly distributed among non-O157 STEC isolates of cattle (57.9%) and goats (57.1%). Key words: Non-O157 STEC, cattle, goats, virulence genes.
- Published
- 2013
39. Adherence of Non-O157 Shiga Toxin–ProducingEscherichia colito Bovine Recto-anal Junction Squamous Epithelial Cells Appears to Be Mediated by Mechanisms Distinct from Those Used by O157
- Author
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Manohar John, Indira T. Kudva, and Carolyn J. Hovde
- Subjects
Serotype ,Anal Canal ,Rectum ,Biology ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Microbiology ,Bacterial Adhesion ,Non o157 ,fluids and secretions ,Cell Line, Tumor ,Cell Adhesion ,medicine ,Animals ,Humans ,Serotyping ,Cell adhesion ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Intimin ,Adhesins, Escherichia coli ,Shiga-Toxigenic Escherichia coli ,Immune Sera ,Epithelial Cells ,Original Articles ,biochemical phenomena, metabolism, and nutrition ,Bacterial adhesin ,medicine.anatomical_structure ,Cattle ,Animal Science and Zoology ,Food Science - Abstract
This study presents evidence that the pattern (diffuse or aggregative) of adherence of clinically relevant non-O157 Shiga toxin–producing Escherichia coli (STEC) to bovine recto-anal junction squamous epithelial cells is similar to that of E. coli O157, although the mechanisms of adherence appear to be distinct. Our results further suggest that novel adhesins, and not Intimin, are likely involved in non-O157 STEC adherence to bovine recto-anal junction squamous epithelial cells. These findings have important implications for the development of efficacious modalities for blocking adherence of non-O157 STEC to bovine gastrointestinal epithelial cells.
- Published
- 2013
40. Serotypes and virulotypes of non-O157 shiga-toxin producing Escherichia coli (STEC) on bovine hides and carcasses
- Author
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Áine Monaghan, David A. McDowell, B. Byrne, Torres Sweeney, Séamus Fanning, and Declan Bolton
- Subjects
Serotype ,Meat ,Surveillance data ,Shiga-Toxigenic Escherichia coli ,Virulence Factors ,Escherichia coli Proteins ,Cattle Diseases ,Food Contamination ,Biology ,Shiga Toxins ,Polymerase Chain Reaction ,Microbiology ,Non o157 ,Shiga toxin producing ,Animals ,Cattle ,Serotyping ,Adhesins, Bacterial ,Shiga toxin-producing Escherichia coli ,Abattoirs ,Escherichia coli Infections ,Phylogeny ,Food Science - Abstract
Four hundred and fifty beef animal hides and a similar number of carcasses were screened for STEC in 3 beef abattoirs over a 12 month period using PCR and culture based methods. 67% (301/450) of hides and 27% (122/450) of carcasses were STEC PCR positive. Forty isolates representing 12 STEC serotypes (O5:H-, O13:H2, O26:H11, O33:H11, O55:H11, O113:H4, O128:H8, O136:H12, O138:H48, O150:H2, O168:H8 and ONT:H11) and 15 serotype–virulotype combinations were identified. This study provides much needed non-O157 STEC surveillance data and also provides further evidence of bovines as a source of clinically significant STEC as well as identifying 3 emerging serotypes O5:H- ( eae -β1), O13:H2 ( eae -ζ), and O150:H2 ( eae -ζ) that should be considered when developing beef testing procedures for non-O157 STEC.
- Published
- 2012
41. Non-O157 Shiga toxin-producing Escherichia coli in retail ground beef and pork in the Washington D.C. area
- Author
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Sherry Ayers, Shaohua Zhao, Mohamed Badaoui Najjar, Jinling Shen, Wenting Ju, Magaly Toro, Jianghong Meng, and Yi Li
- Subjects
Meat ,Swine ,Antimicrobial susceptibility ,Virulence ,Food Contamination ,Biology ,Shiga Toxins ,medicine.disease_cause ,Microbiology ,Non o157 ,fluids and secretions ,STX2 ,Drug Resistance, Bacterial ,Pulsed-field gel electrophoresis ,medicine ,Animals ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Shiga-Toxigenic Escherichia coli ,food and beverages ,biochemical phenomena, metabolism, and nutrition ,bacterial infections and mycoses ,Antimicrobial ,Anti-Bacterial Agents ,Consumer Product Safety ,District of Columbia ,bacteria ,Cattle ,Food Science - Abstract
The prevalence and characteristics of non-O157 Shiga toxin-producing Escherichia coli (STEC) in retail ground meat from the Washington D.C. area were investigated in this study. STEC from 480 ground beef and pork samples were identified using PCR screening followed by colony hybridization. The STEC isolates were serogrouped and examined for the presence of virulence genes (stx1, stx2, eae and hlyA), and antimicrobial susceptibility. PFGE was used to identify the clonal relationships of STEC isolates, and PCR-RFLP was employed to determine stx subtypes. In addition, the cytotoxicity of STEC isolates was determined using a Vero cell assay. STEC were identified in 12 (5.2%) of 231 ground pork and 13 (5.2%) of 249 ground beef samples. Among 32 STEC isolates recovered from the 25 samples, 12 (37.5%) carried stx2dact and 7 (21.9%) carried hlyA, but none carried eae. Nine isolates were identified as O91, and 17 (53.1%) isolates were resistant to two or more antimicrobials. Verotoxicity was detected in 26 (81.3%) of the STEC isolates. Thus, the retail ground meat was contaminated with a heterogeneous population of non-O157 STEC, some of which were potential human pathogens.
- Published
- 2012
42. Effect of Stress on Non-O157 Shiga Toxin–Producing Escherichia coli
- Author
-
James L. Smith and Pina M. Fratamico
- Subjects
Food Handling ,Colony Count, Microbial ,Food Contamination ,Biology ,medicine.disease_cause ,Microbiology ,Non o157 ,fluids and secretions ,Stress, Physiological ,Acid tolerance ,medicine ,Animals ,Humans ,Food science ,Serotyping ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Shiga-Toxigenic Escherichia coli ,business.industry ,biochemical phenomena, metabolism, and nutrition ,bacterial infections and mycoses ,Food safety ,Adaptation, Physiological ,Consumer Product Safety ,High pressure ,Food Microbiology ,bacteria ,Arginine decarboxylase ,business ,Food Science - Abstract
Non-O157 Shiga toxin-producing Escherichia coli (non-O157 STEC) strains have emerged as important foodborne pathogens worldwide. Non-O157 STEC serogroups O26, O45, O103, O111, O121, and O145 have been declared as adulterants in beef by the U. S. Department of Agriculture Food Safety and Inspection Service. While documentation is limited, treatments including heat and acid that have been shown to inactivate E. coli O157:H7 will likely also destroy non-O157 STEC; however, non-O157 STEC strains show variability in their responses to stress. It has been shown that non-O157 STEC may survive in fermented sausages and cheeses, and treatments such as high pressure may be necessary to eliminate non-O157 STEC from these products. The mechanisms used by non-O157 STEC to resist acid environments are similar to those used by O157:H7 strains and include the acid tolerance response, the oxidative system, and the glutamate and arginine decarboxylase systems. However, one study demonstrated that some non-O157 STEC strains utilize a chaperone-based acid stress response (HdeA and HdeB) to combat acidic conditions, which is lacking in E. coli O157:H7. Genomic studies suggest that while non-O157 STEC can cause diseases similar to those caused by E. coli O157:H7, O157 and non-O157 STECs have different evolutionary histories. Non-O157 STECs are a heterogeneous group of organisms, and there is currently a limited amount of information on their virulence, fitness, and stress responses, rendering it difficult to draw firm conclusions on their behavior when exposed to stress in the environment, in food, and during processing.
- Published
- 2012
43. Mathematical modeling and numerical analysis of the growth of non-O157 Shiga toxin-producing Escherichia coli in spinach leaves
- Author
-
Lihan Huang
- Subjects
Population ,Colony Count, Microbial ,Food Contamination ,Biology ,Bacterial growth ,medicine.disease_cause ,Microbiology ,Non o157 ,fluids and secretions ,Spinacia oleracea ,medicine ,Humans ,Food science ,education ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,education.field_of_study ,Shiga-Toxigenic Escherichia coli ,Temperature ,General Medicine ,Growth curve (biology) ,bacterial infections and mycoses ,biology.organism_classification ,Kinetics ,Area Under Curve ,Food Microbiology ,bacteria ,Spinach ,Mathematics ,Bacteria ,Food Science - Abstract
This study was conducted to investigate the growth of non-O157 Shiga toxin-producing Escherichia coli (STEC) in spinach leaves and to develop kinetic models to describe the bacterial growth. Six serogroups of non-O157 STEC, including O26, O45, O103, O111, O121, and O145, were used in the growth studies conducted isothermally at 4, 8, 15, 20, 25, 30, and 35 °C. Both STEC and background microflora were enumerated to develop kinetic models. Growth of STEC in spinach leaves was observed at elevated temperatures (15–35 °C), but not at 4 and 8 °C. This study considered the dynamic interactions between the STEC cells and the background microflora. A modified Lotka–Volterra and logistic equation was used to simulate the bacterial growth. In combination with an unconstrained optimization procedure, the differential growth equations were solved numerically to evaluate the dynamic interactions between the STEC cells and the background microflora, and to determine the kinetic parameters by fitting each growth curve to the growth equations. A close agreement between the experimental growth curves and the numerical analysis results was obtained. The analytical results showed that the growth of STEC in spinach leaves was unhindered when the population was low, but the growth was suppressed by the background microflora as the STEC population approached the maximum population density. The effect of temperature on the growth of both STEC and background microflora was also evaluated. Secondary models, evaluating the effect of temperature on growth rates, were also developed. The estimated apparent minimum growth temperature for STEC was 11 °C in commercial spinach leaves. The methodology and results of this study can be used to examine the dynamic interactions and growth between different bacteria in foods, and to conduct risk assessments of STEC in spinach leaves.
- Published
- 2012
44. High-Quality Draft Genome Sequences for Five Non-O157 Shiga Toxin-Producing Escherichia coli Strains Generated with PacBio Sequencing and Optical Maps
- Author
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Devon Stripling, Vladimir N. Loparev, Phalasy Juieng, Lori A. Rowe, Rebecca L. Lindsey, Kristen Knipe, Dhwani Batra, Nancy Strockbine, Eija Trees, Lisley Garcia-Toledo, and Haley Martin
- Subjects
0301 basic medicine ,Serotype ,Genetics ,Foodborne pathogen ,animal diseases ,biochemical phenomena, metabolism, and nutrition ,Biology ,bacterial infections and mycoses ,medicine.disease_cause ,Genome ,Non o157 ,Microbiology ,03 medical and health sciences ,fluids and secretions ,030104 developmental biology ,medicine ,bacteria ,Prokaryotes ,Molecular Biology ,Shiga toxin-producing Escherichia coli ,Escherichia coli - Abstract
Shiga toxin-producing Escherichia coli (STEC) is a foodborne pathogen. We report here the high-quality draft whole-genome sequences of five STEC strains isolated from clinical cases in the United States. This report is for STEC of serotypes O55:H7, O79:H7, O91:H14, O153:H2, and O156:H25.
- Published
- 2016
45. Fast detection of both O157 and non-O157 shiga-toxin producing Escherichia coli by real-time optical immunoassay
- Author
-
Sabine Delannoy, Sami Slimani, Thierry Livache, Patrick Fach, Raphael Mathey, L. Mondani, Thibaut Mercey, Félix Piat, Yoann Roupioz, Laboratoire Sécurité des Aliments, Plateforme IdentyPath, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES), BIOMERIEUX, Laboratoire d'Ecologie Microbienne - UMR 5557 (LEM), Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Vétérinaire de Lyon (ENVL)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Recherche Agronomique (INRA)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS), SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Chimie pour la Reconnaissance et l’Etude d’Assemblages Biologiques (CREAB), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Structures et propriétés d'architectures moléculaire (SPRAM - UMR 5819), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de sécurité des aliments de Maisons-Alfort (LSAl), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Nanosciences et Cryogénie (INAC), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
- Subjects
0301 basic medicine ,Identification ,[SDV.BIO]Life Sciences [q-bio]/Biotechnology ,Antibody microarray ,Microarray ,Rapid methods ,medicine.disease_cause ,Polymerase Chain Reaction ,Applied Microbiology and Biotechnology ,Non o157 ,Food safety ,Microbiology ,Foodborne Diseases ,03 medical and health sciences ,fluids and secretions ,[SDV.IDA]Life Sciences [q-bio]/Food engineering ,medicine ,Surface plasmon resonance ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,ComputingMilieux_MISCELLANEOUS ,Immunoassay ,Chromatography ,Shiga-Toxigenic Escherichia coli ,medicine.diagnostic_test ,Chemistry ,[CHIM.ORGA]Chemical Sciences/Organic chemistry ,Escherichia coli Proteins ,Surface Plasmon Resonance ,[SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology ,3. Good health ,Molecular Typing ,030104 developmental biology ,EHEC (enterohaemorrhagic E. coli) ,DNA microarray - Abstract
UNLABELLED Among bacterial pathogens involved in food-illnesses, seven serogroups (O26, O45, O103, O111, O121, O145 and O157) of Shiga-toxin producing Escherichia coli (STEC), are frequently identified. During such outbreak, and due to the perishable property of most foodstuff, the time laps for the identification of contaminated products and pathogens is thus critical to better circumvent their spread. Traditional detection methods using PCR or culture plating are time consuming and may present some limitations. In this study, we present a multiplexed immunoassay for the optical detection of most commonly enterohemorrhagic E. coli serogroups: O26, O45, O103, O111, O121, O145 and O157:H7 in a single device. The use of Surface Plasmon Resonance imaging not only enabled the label-free analysis of the samples but gave results in a real-time manner. A dedicated protocol was set up for the detection of both low contaminating bacterial concentrations of food samples (5 CFU per 25 g) and postenrichment aliquots. By combining one single device for the detection of O157 and non-O157 STEC in a label-free manner, this rapid approach may have an important economic and societal impact. SIGNIFICANCE AND IMPACT OF THE STUDY This article presents a simple-to-operate immunoassay for the specific detection of Shiga-toxin producing Escherichia coli (STEC). This approach consists in the on-chip assay detection of viable cells on a specifically designed antibody microarray. By skipping any enrichment step and avoiding the use of labelling agent, this approach based on the Surface Plasmon Resonance imaging of the microarrays turns out to be much faster and more cost effective by comparison with standardized methods.
- Published
- 2016
46. Predicting the Presence of Non-O157 Shiga Toxin-Producing Escherichia coli in Ground Beef by Using Molecular Tests for Shiga Toxins, Intimin, and O Serogroups
- Author
-
Joseph M. Bosilevac and Mohammad Koohmaraie
- Subjects
Meat ,Escherichia coli Proteins ,Shiga Toxins ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Non o157 ,Microbiology ,Bacterial genetics ,fluids and secretions ,mental disorders ,medicine ,Adhesins, Bacterial ,Shiga toxin-producing Escherichia coli ,Escherichia coli ,Intimin ,Shiga-Toxigenic Escherichia coli ,Ecology ,biology ,Chemistry ,O Antigens ,Shiga toxin ,bacterial infections and mycoses ,Bacterial adhesin ,Food Microbiology ,biology.protein ,bacteria ,psychological phenomena and processes ,Food Science ,Biotechnology - Abstract
When 3,972 ground beef enrichments with 6 confirmed to contain a non-O157 Shiga toxin-producing intimin-positive Escherichia coli isolate were tested for Shiga toxin, intimin, and O group (O26, O45, O103, O111, O121, and O145) genes, 183 potential positives and only 2 of the 6 confirmed positives were identified.
- Published
- 2012
47. Non-O157 Shiga Toxin–producingEscherichia coliAssociated with Venison
- Author
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Carrie E. Rigdon, Bonnie S. Koziol, Gregory T. Danzeisen, Ginette L. Short, Levi J. Muhl, Bryanne T. Shaw, Matthew Forstner, Kirk E. Smith, Charlott Taylor, and Joshua Rounds
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Diarrhea ,Male ,Microbiology (medical) ,Meat ,Adolescent ,Epidemiology ,Minnesota ,education ,lcsh:Medicine ,Washing hands ,medicine.disease_cause ,Non o157 ,Disease Outbreaks ,Shiga Toxin ,lcsh:Infectious and parasitic diseases ,Microbiology ,Foodborne Diseases ,Escherichia coli ,medicine ,Animals ,Humans ,lcsh:RC109-216 ,Serotyping ,bacteria ,Non-O157 Shiga toxin–producing Escherichia coli ,Shiga toxin-producing Escherichia coli ,Escherichia coli Infections ,Shiga-Toxigenic Escherichia coli ,outbreak ,biology ,Deer ,lcsh:R ,Dispatch ,Outbreak ,Shiga toxin ,United States ,white-tailed deer ,STEC ,Infectious Diseases ,pulsed-field gel electrophoresis ,venison ,Case-Control Studies ,surveillance ,biology.protein ,Female ,medicine.symptom - Abstract
News reports of “E. coli outbreaks” usually refer to Shiga toxin–producing E. coli O157. But there are other types of Shiga toxin–producing E. coli, often called STEC,about which less is known. For these other types of STEC, what is the source? What are the risk factors? An outbreak among 29 high school students in Minnesota provided some answers. The source of this outbreak was a white-tailed deer that had been butchered and eaten at the school. The risk factors for infection were handling raw or eating undercooked venison. To prevent this type of STECinfection, people should handle and cook venison with the same caution recommended for other meats., We investigated an outbreak of non-O157 Shiga toxin–producing Escherichia coli at a high school in Minnesota, USA, in November 2010. Consuming undercooked venison and not washing hands after handling raw venison were associated with illness. E. coli O103:H2 and non-Shiga toxin–producing E. coli O145:NM were isolated from ill students and venison.
- Published
- 2012
48. Increasing incidence of non-O157 Shiga toxin-producing Escherichia coli (STEC) in Michigan and association with clinical illness
- Author
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Tara O. Henderson, Marion Tseng, James T. Rudrik, Shannon D. Manning, Qiong Sha, Julie A. Funk, and James Collins
- Subjects
0301 basic medicine ,Serotype ,Adult ,Male ,medicine.medical_specialty ,Michigan ,Adolescent ,Epidemiology ,animal diseases ,030106 microbiology ,Population ,Non o157 ,Microbiology ,03 medical and health sciences ,Young Adult ,fluids and secretions ,Disease severity ,Age groups ,Internal medicine ,medicine ,Humans ,education ,Child ,Shiga toxin-producing Escherichia coli ,Escherichia coli Infections ,Aged ,Aged, 80 and over ,education.field_of_study ,Shiga-Toxigenic Escherichia coli ,business.industry ,Incidence (epidemiology) ,Incidence ,Infant, Newborn ,Infant ,biochemical phenomena, metabolism, and nutrition ,Middle Aged ,bacterial infections and mycoses ,Original Papers ,Infectious Diseases ,Child, Preschool ,Hemolytic-Uremic Syndrome ,bacteria ,Female ,business - Abstract
SUMMARYInfection with Shiga toxin-producing Escherichia coli (STEC) by serotypes other than O157 (non-O157) have been increasingly reported in the United States. This increase in reporting is primarily due to the improvements in diagnostic tests. We analysed 1497 STEC cases reported in Michigan from 2001 to 2012. A significant increase in the number of non-O157 STEC cases was observed over time, and similar incidence rates were observed for O157 and non-O157 STEC cases in certain time periods. The odds of hospitalization was two times higher in O157 STEC cases relative to non-O157 STEC cases when adjusted for age and gender, suggesting that O157 STEC causes more severe clinical outcomes in all age groups. The use of population-based surveillance to better define trends and associations with disease severity are critical to enhance our understanding of STEC infections and improve upon current prevention and control efforts.
- Published
- 2015
49. Growth of Stressed Strains of Four Non-O157 Shiga Toxin-Producing Escherichia coli Serogroups in Five Enrichment Broths
- Author
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Marc Heyndrickx, Inge Van Damme, Bavo Verhaegen, Lieven De Zutter, and Koen De Reu
- Subjects
education.field_of_study ,food.ingredient ,Shiga-Toxigenic Escherichia coli ,Population ,Biology ,medicine.disease_cause ,Immunomagnetic separation ,Serogroup ,Microbiology ,Tryptic soy broth ,Non o157 ,Culture Media ,chemistry.chemical_compound ,fluids and secretions ,Sodium pyruvate ,food ,chemistry ,medicine ,Agar ,education ,Escherichia coli ,Shiga toxin-producing Escherichia coli ,Food Science - Abstract
The purpose of this study was to evaluate (i) the behavior of several strains of non-O157 Shiga toxin-producing Escherichia coli (STEC) serogroups (O26, O103, O111, and O145) exposed to different stress conditions and (ii) the growth dynamics of stressed and nonstressed non-O157 STEC cells in five enrichment media. STEC strains were exposed to acid, cold, and freeze stresses. Lethal and sublethal injuries were determined by plating in parallel on selective and nonselective agar media. Freeze stress (8 days, 20°C) caused the most lethal (95.3% ± 2.5%) injury, as well as the most sublethal (89.1% ± 8.8%) injury in the surviving population. Growth of stressed and nonstressed pure cultures of non-O157 STEC on modified tryptic soy broth, buffered peptone water (BPW), BPW with sodium pyruvate, Brila, and STEC enrichment broth (SEB) was determined using total viable counts. To compare growth capacities, growth after 7 and 24 h of enrichment was measured; lag phases and maximum growth rates were also calculated. In general, growth on BPW resulted in a short lag phase followed by a high maximum growth rate during the enrichment of all tested strains when using all three stress types. Furthermore, BPW ensured the highest STEC count after 7 h of growth. Supplementing the medium with sodium pyruvate did not improve the growth dynamics. The two selective media, Brila and SEB, were less efficient than BPW, but Brila's enrichment performance was remarkably better than that of SEB. This study shows that irrespective of the effect of background flora, BPW is still recommended for resuscitation of non-O157 STEC.
- Published
- 2015
50. Erratum: Jimena Soledad Cadona, et al.; Pathogenicity Islands Distribution in Non-O157 Shiga Toxin-Producing Escherichia coli (STEC). Genes 2018, 9, 81
- Author
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Ana Victoria Bustamante, Juliana González, Jimena Soledad Cadona, and Andrea Mariel Sanso
- Subjects
0301 basic medicine ,lcsh:QH426-470 ,Biology ,Pathogenicity island ,Non o157 ,Microbiology ,lcsh:Genetics ,03 medical and health sciences ,n/a ,030104 developmental biology ,Genetics ,Erratum ,Gene ,Shiga toxin-producing Escherichia coli ,Genetics (clinical) - Abstract
We wish to make the following correction to the paper by Soledad-Cadona et al.[...]
- Published
- 2018
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