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Abuzerr S, Hadi M, Zinszer K, Nasseri S, Yunesian M, Mahvi AH, Nabizadeh R, Mohammed SH. Quantitative microbial risk assessment for Escherichia Coli O157: H7 via drinking water in the Gaza Strip, Palestine. SAGE Open Med 2024; 12:20503121241258071. [PMID: 38846513 PMCID: PMC11155367 DOI: 10.1177/20503121241258071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 05/13/2024] [Indexed: 06/09/2024] Open
Abstract
Introduction Microbial contamination of drinking water, particularly by pathogens such as Escherichia coli O157: H7, is a significant public health concern worldwide, especially in regions with limited access to clean water like the Gaza Strip. However, few studies have quantified the disease burden associated with E. coli O157: H7 contamination in such challenging water management contexts. Objective This study aimed to conduct a comprehensive Quantitative Microbial Risk Assessment to estimate the annual infection risk and disease burden attributed to E. coli O157: H7 in Gaza's drinking water. Methods Applying the typical four steps of the Quantitative Microbial Risk Assessment technique-hazard identification, exposure assessment, dose-response analysis, and risk characterization-the study assessed the microbial risk associated with E. coli O157: H7 contamination in Gaza's drinking water supply. A total of 1317 water samples from various sources across Gaza were collected and analyzed for the presence of E. coli O157: H7. Using Microsoft ExcelTM and @RISKTM software, a Quantitative Microbial Risk Assessment model was constructed to quantify the risk of infection associated with E. coli O157: H7 contamination. Monte Carlo simulation techniques were employed to assess uncertainty surrounding input variables and generate probabilistic estimates of infection risk and disease burden. Results Analysis of the water samples revealed the presence of E. coli O157: H7 in 6.9% of samples, with mean, standard deviation, and maximum values of 1.97, 9.74, and 112 MPN/100 ml, respectively. The risk model estimated a median infection risk of 3.21 × 10-01 per person per year and a median disease burden of 3.21 × 10-01 Disability-Adjusted Life Years per person per year, significantly exceeding acceptable thresholds set by the WHO. Conclusion These findings emphasize the urgent need for proactive strategies to mitigate public health risks associated with waterborne pathogens in Gaza.
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Affiliation(s)
- Samer Abuzerr
- Department of Medical Sciences, University College of Science and Technology—Khan Younis, Gaza, Occupied Palestinian Territory
- Department of Social and Preventive Medicine, School of Public Health, University of Montreal, Montréal, QC, Canada
| | - Mahdi Hadi
- Center for Water Quality Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Kate Zinszer
- Department of Social and Preventive Medicine, School of Public Health, University of Montreal, Montréal, QC, Canada
| | - Simin Nasseri
- Center for Water Quality Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
- Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Masud Yunesian
- Center for Water Quality Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
- Department of Research Methodology and Data Analysis, Institute for Environmental Research, TUMS, Tehran, Iran
| | - Amir Hossein Mahvi
- Center for Water Quality Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Ramin Nabizadeh
- Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Shimels Hussien Mohammed
- Department of Public Health, School of Public Health, St. Paul’s Hospital Millennium Medical College, Addis Ababa, Ethiopia
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Ma D, Weir MH, Hull NM. Fluence-based QMRA model for bacterial photorepair and regrowth in drinking water after decentralized UV disinfection. WATER RESEARCH 2023; 231:119612. [PMID: 36706469 DOI: 10.1016/j.watres.2023.119612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 12/19/2022] [Accepted: 01/13/2023] [Indexed: 06/18/2023]
Abstract
Ultraviolet disinfection is a promising solution for decentralized drinking water systems such as communal water taps. A potential health risk is enzymatic photorepair of pathogens after UV disinfection, which can result in regrowth of pathogens. Even though photorepair is a known issue, no formal risk assessments have been conducted for photorepair after UV disinfection in drinking water. The main objective was to construct a quantitative microbial risk assessment (QMRA) of photorepair after UV disinfection of drinking water in a decentralized system. UV disinfection and photorepair kinetics for E. coli were modelled using reproducible fluence-based determinations. Impacts of water collection patterns, and wavelength-dependent water container material transmittance, sunlight intensity, and photorepair enzyme absorbance were quantified. After UV disinfection by 16 or 40 mJ/cm2 of < 5-log microorganisms per L, risk of infection did not exceed 1-in-10,000 under conditions permitting E. coli photorepair. Risk from photorepair was less than 1-in-10,000 for photorepair light exposure < 0.75 h throughout the day for UV fluence 16 mJ/cm2 or greater. UV disinfection followed by solar disinfection surpassing photoreactivation during storage reduced risk below 1-in-10,000 for photorepair light exposure > 2.5 h between modelled times of 9 AM - 3 PM. The model can be expanded to other pathogens as UV fluence and photorepair fluence response kinetics become available, and this QMRA can be used to inform the placement of community water access points to reduce risk of photorepair and ensure adequate shelf life of UV disinfected water under safe storage conditions.
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Affiliation(s)
- Daniel Ma
- College of Engineering, Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH 43210, USA
| | - Mark H Weir
- Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH 43210, USA; Sustainability Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Natalie M Hull
- College of Engineering, Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH 43210, USA; Sustainability Institute, The Ohio State University, Columbus, OH 43210, USA.
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Dankittipong N, Fischer EAJ, Swanenburg M, Wagenaar JA, Stegeman AJ, de Vos CJ. Quantitative Risk Assessment for the Introduction of Carbapenem-Resistant Enterobacteriaceae (CPE) into Dutch Livestock Farms. Antibiotics (Basel) 2022; 11:antibiotics11020281. [PMID: 35203883 PMCID: PMC8868399 DOI: 10.3390/antibiotics11020281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 02/09/2022] [Accepted: 02/15/2022] [Indexed: 12/10/2022] Open
Abstract
Early detection of emerging carbapenem-resistant Enterobacteriaceae (CPE) in food-producing animals is essential to control the spread of CPE. We assessed the risk of CPE introduction from imported livestock, livestock feed, companion animals, hospital patients, and returning travelers into livestock farms in The Netherlands, including (1) broiler, (2) broiler breeder, (3) fattening pig, (4) breeding pig, (5) farrow-to-finish pig, and (6) veal calf farms. The expected annual number of introductions was calculated from the number of farms exposed to each CPE source and the probability that at least one animal in an exposed farm is colonized. The total number of farms with CPE colonization was estimated to be the highest for fattening pig farms, whereas the probability of introduction for an individual farm was the highest for broiler farms. Livestock feed and imported livestock are the most likely sources of CPE introduction into Dutch livestock farms. Sensitivity analysis indicated that the number of fattening pig farms determined the number of high introductions in fattening pigs from feed, and that uncertainty on CPE prevalence impacted the absolute risk estimate for all farm types. The results of this study can be used to inform risk-based surveillance for CPE in livestock farms.
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Affiliation(s)
- Natcha Dankittipong
- Department Population Health Sciences, Farm Animal Health, Utrecht University, Martinus G. de Bruingebouw, Yalelaan 7, 3584 CL Utrecht, The Netherlands; (E.A.J.F.); (A.J.S.)
- Correspondence:
| | - Egil A. J. Fischer
- Department Population Health Sciences, Farm Animal Health, Utrecht University, Martinus G. de Bruingebouw, Yalelaan 7, 3584 CL Utrecht, The Netherlands; (E.A.J.F.); (A.J.S.)
| | - Manon Swanenburg
- Wageningen Bioveterinary Research, Wageningen University & Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (M.S.); (C.J.d.V.)
| | - Jaap A. Wagenaar
- Department Biomolecular Health Science, Infectious Diseases & Immunology, Utrecht University, Androclusgebouw, Yalelaan 1, 3584 CL Utrecht, The Netherlands;
| | - Arjan J. Stegeman
- Department Population Health Sciences, Farm Animal Health, Utrecht University, Martinus G. de Bruingebouw, Yalelaan 7, 3584 CL Utrecht, The Netherlands; (E.A.J.F.); (A.J.S.)
| | - Clazien J. de Vos
- Wageningen Bioveterinary Research, Wageningen University & Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (M.S.); (C.J.d.V.)
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Machado MC, Zamani M, Daniel S, Furst AL. Bioelectrochemical platforms to study and detect emerging pathogens. MRS BULLETIN 2021; 46:840-846. [PMID: 34483472 PMCID: PMC8407123 DOI: 10.1557/s43577-021-00172-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 08/05/2021] [Indexed: 06/13/2023]
Abstract
The ongoing SARS-CoV-2 pandemic has emphasized the importance of technologies to rapidly detect emerging pathogens and understand their interactions with hosts. Platforms based on the combination of biological recognition and electrochemical signal transduction, generally termed bioelectrochemical platforms, offer unique opportunities to both sense and study pathogens. Improved bio-based materials have enabled enhanced control over the biotic-abiotic interface in these systems. These improvements have generated platforms with the capability to elucidate biological function rather than simply detect targets. This advantage is a key feature of recent bioelectrochemical platforms applied to infectious disease. Here, we describe developments in materials for bioelectrochemical platforms to study and detect emerging pathogens. The incorporation of host membrane material into electrochemical devices has provided unparalleled insights into the interaction between viruses and host cells, and new capture methods have enabled the specific detection of bacterial pathogens, such as those that cause secondary infections with SARS-CoV-2. As these devices continue to improve through the merging of hi-tech materials and biomaterials, the scalability and commercial viability of these devices will similarly improve.
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Affiliation(s)
- Mary C. Machado
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, USA
| | - Marjon Zamani
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, USA
| | - Susan Daniel
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, USA
| | - Ariel L. Furst
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, USA
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Shurson GC, Urriola PE, van de Ligt JLG. Can we effectively manage parasites, prions, and pathogens in the global feed industry to achieve One Health? Transbound Emerg Dis 2021; 69:4-30. [PMID: 34171167 DOI: 10.1111/tbed.14205] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/14/2021] [Accepted: 06/22/2021] [Indexed: 11/30/2022]
Abstract
Prions and certain endoparasites, bacteria, and viruses are internationally recognized as types of disease-causing biological agents that can be transmitted from contaminated feed to animals. Historically, foodborne biological hazards such as prions (transmissible spongiform encephalopathy), endoparasites (Trichinella spiralis, Toxoplasma gondii), and pathogenic bacteria (Salmonella spp., Listeria monocytogenes, Escherichia coli O157, Clostridium spp., and Campylobacter spp.) were major food safety concerns from feeding uncooked or improperly heated animal-derived food waste and by-products. However, implementation of validated thermal processing conditions along with verifiable quality control procedures has been effective in enabling safe use of these feed materials in animal diets. More recently, the occurrence of global Porcine Epidemic Diarrhea Virus and African Swine Fever Virus epidemics, dependence on international feed ingredient supply chains, and the discovery that these viruses can survive in some feed ingredient matrices under environmental conditions of trans-oceanic shipments has created an urgent need to develop and implement rigorous biosecurity protocols that prevent and control animal viruses in feed ingredients. Implementation of verifiable risk-based preventive controls, traceability systems from origin to destination, and effective mitigation procedures is essential to minimize these food security, safety, and sustainability threats. Creating a new biosafety and biosecurity framework will enable convergence of the diverging One Health components involving low environmental impact and functional feed ingredients that are perceived as having elevated biosafety risks when used in animal feeds.
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Affiliation(s)
- Gerald C Shurson
- Department of Animal Science, College of Food Agricultural and Natural Resource Sciences, University of Minnesota, St. Paul, Minnesota, USA
| | - Pedro E Urriola
- Department of Animal Science, College of Food Agricultural and Natural Resource Sciences, University of Minnesota, St. Paul, Minnesota, USA
| | - Jennifer L G van de Ligt
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA
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Klass SH, Sofen LE, Hallberg ZF, Fiala TA, Ramsey AV, Dolan NS, Francis MB, Furst AL. Covalent capture and electrochemical quantification of pathogenic E. coli. Chem Commun (Camb) 2021; 57:2507-2510. [PMID: 33585846 PMCID: PMC9274617 DOI: 10.1039/d0cc08420d] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
Pathogenic E. coli pose a significant threat to public health, as strains of this species cause both foodborne illnesses and urinary tract infections. Using a rapid bioconjugation reaction, we selectively capture E. coli at a disposable gold electrode from complex solutions and accurately quantify the pathogenic microbes using electrochemical impedance spectroscopy.
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Affiliation(s)
- Sarah H Klass
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Laura E Sofen
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Zachary F Hallberg
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
| | - Tahoe A Fiala
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Alexandra V Ramsey
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Nicholas S Dolan
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Matthew B Francis
- Department of Chemistry, University of California, Berkeley, California 94720, USA and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Ariel L Furst
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
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García A, Fox JG. A One Health Perspective for Defining and Deciphering Escherichia coli Pathogenic Potential in Multiple Hosts. Comp Med 2021; 71:3-45. [PMID: 33419487 PMCID: PMC7898170 DOI: 10.30802/aalas-cm-20-000054] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/17/2020] [Accepted: 09/19/2020] [Indexed: 11/05/2022]
Abstract
E. coli is one of the most common species of bacteria colonizing humans and animals. The singularity of E. coli 's genus and species underestimates its multifaceted nature, which is represented by different strains, each with different combinations of distinct virulence factors. In fact, several E. coli pathotypes, or hybrid strains, may be associated with both subclinical infection and a range of clinical conditions, including enteric, urinary, and systemic infections. E. coli may also express DNA-damaging toxins that could impact cancer development. This review summarizes the different E. coli pathotypes in the context of their history, hosts, clinical signs, epidemiology, and control. The pathotypic characterization of E. coli in the context of disease in different animals, including humans, provides comparative and One Health perspectives that will guide future clinical and research investigations of E. coli infections.
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Key Words
- aa, aggregative adherence
- a/e, attaching and effacing
- aepec, atypical epec
- afa, afimbrial adhesin
- aida-i, adhesin involved in diffuse adherence
- aiec, adherent invasive e. coli
- apec, avian pathogenic e. coli
- atcc, american type culture collection
- bfp, bundle-forming pilus
- cd, crohn disease
- cdt, cytolethal distending toxin gene
- clb, colibactin
- cnf, cytotoxic necrotizing factor
- cs, coli surface (antigens)
- daec, diffusely adhering e. coli
- db, dutch belted
- eae, e. coli attaching and effacing gene
- eaec, enteroaggregative e. coli
- eaf, epec adherence factor (plasmid)
- eahec, entero-aggregative-hemorrhagic e. coli
- east-1, enteroaggregative e. coli heat-stable enterotoxin
- e. coli, escherichia coli
- ed, edema disease
- ehec, enterohemorrhagic e. coli
- eiec, enteroinvasive e. coli
- epec, enteropathogenic e. coli
- esbl, extended-spectrum β-lactamase
- esp, e. coli secreted protein
- etec, enterotoxigenic e. coli
- expec, extraintestinal pathogenic e. coli
- fyua, yersiniabactin receptor gene
- gi, gastrointestinal
- hly, hemolysin
- hus, hemolytic uremic syndrome
- ibd, inflammatory bowel disease
- la, localized adherence
- lee, locus of enterocyte effacement
- lpf, long polar fimbriae
- lt, heat-labile (enterotoxin)
- mlst, multilocus sequence typing
- ndm, new delhi metallo-β-lactamase
- nzw, new zealand white
- pap, pyelonephritis-associated pilus
- pks, polyketide synthase
- sfa, s fimbrial adhesin
- slt, shiga-like toxin
- st, heat-stable (enterotoxin)
- stec, stx-producing e. coli
- stx, shiga toxin
- tepec, typical epec
- upec, uropathogenic e. coli
- uti, urinary tract infection
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Affiliation(s)
- Alexis García
- Molecular Sciences Research Center, University of Puerto Rico, San Juan, Puerto Rico; Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts; Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts;,
| | - James G Fox
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
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Granica S, Vahjen W, Zentek J, Melzig MF, Pawłowska KA, Piwowarski JP. Lythrum salicaria Ellagitannins Stimulate IPEC-J2 Cells Monolayer Formation and Inhibit Enteropathogenic Escherichia coli Growth and Adhesion. JOURNAL OF NATURAL PRODUCTS 2020; 83:3614-3622. [PMID: 33270444 PMCID: PMC7771025 DOI: 10.1021/acs.jnatprod.0c00776] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Indexed: 06/12/2023]
Abstract
Lythrum salicaria herb (LSH) was applied in diarrhea therapy since ancient times. Despite empirically referenced therapeutic effects, the bioactivity mechanisms and chemical constituents responsible for pharmacological activity remain not fully resolved. Taking into consideration the historical use of LSH in treatment of diarrhea in humans and farm animals, the aim of the study was to examine in vitro the influence of LSH and its C-glycosylic ellagitannins on processes associated with maintaining intestinal epithelium integrity and enteropathogenic Escherichia coli (EPEC) growth and adhesion. LSH was not only inhibiting EPEC growth in a concentration dependent manner but also its adhesion to IPEC-J2 intestinal epithelial cell monolayers. Inhibitory activity toward EPEC growth was additionally confirmed ex vivo in distal colon samples of postweaning piglets. LSH and its dominating C-glycosylic ellagitannins, castalagin (1), vescalagin (2), and salicarinins A (3) and B (4) were stimulating IPEC-J2 monolayer formation by enhancing claudin 4 production. Parallelly tested gut microbiota metabolites of LSH ellagitannins, urolithin C (5), urolithin A (6), and its glucuronides (7) were inactive. The activities of LSH and the isolated ellagitannins support its purported antidiarrheal properties and indicate potential mechanisms responsible for its beneficial influence on the intestinal epithelium.
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Affiliation(s)
- Sebastian Granica
- Department
of Pharmacognosy and Molecular Basis of Phytotherapy, Medical University of Warsaw, Warsaw 02-097, Poland
- Centre for Preclinical Studies, Medical
University of Warsaw, Warsaw 02-097, Poland
| | - Wilfried Vahjen
- Institute of Animal Nutrition, Freie Universität
Berlin, Berlin 14195, Germany
| | - Jürgen Zentek
- Institute of Animal Nutrition, Freie Universität
Berlin, Berlin 14195, Germany
| | - Matthias F. Melzig
- Department of Pharmaceutical Biology, Freie
Universität Berlin, Berlin 14195, Germany
| | - Karolina A. Pawłowska
- Department
of Pharmacognosy and Molecular Basis of Phytotherapy, Medical University of Warsaw, Warsaw 02-097, Poland
- Centre for Preclinical Studies, Medical
University of Warsaw, Warsaw 02-097, Poland
| | - Jakub P. Piwowarski
- Department
of Pharmacognosy and Molecular Basis of Phytotherapy, Medical University of Warsaw, Warsaw 02-097, Poland
- Centre for Preclinical Studies, Medical
University of Warsaw, Warsaw 02-097, Poland
- Institute of Animal Nutrition, Freie Universität
Berlin, Berlin 14195, Germany
- Department of Pharmaceutical Biology, Freie
Universität Berlin, Berlin 14195, Germany
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Abstract
Global pork production has largely adopted on-farm biosecurity to minimize vectors of disease transmission and protect swine health. Feed and ingredients were not originally thought to be substantial vectors, but recent incidents have demonstrated their ability to harbor disease. The objective of this paper is to review the potential role of swine feed as a disease vector and describe biosecurity measures that have been evaluated as a way of maintaining swine health. Recent research has demonstrated that viruses such as porcine epidemic diarrhea virus and African Swine Fever Virus can survive conditions of transboundary shipment in soybean meal, lysine, and complete feed, and contaminated feed can cause animal illness. Recent research has focused on potential methods of preventing feed-based pathogens from infecting pigs, including prevention of entry to the feed system, mitigation by thermal processing, or decontamination by chemical additives. Strategies have been designed to understand the spread of pathogens throughout the feed manufacturing environment, including potential batch-to-batch carryover, thus reducing transmission risk. In summary, the focus on feed biosecurity in recent years is warranted, but additional research is needed to further understand the risk and identify cost-effective approaches to maintain feed biosecurity as a way of protecting swine health.
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Sabuj AAM, Haque ZF, Younus MI, Pondit A, Barua N, Hossain MG, Islam MA, Saha S. Microbial risk assessment of ready-to-eat fast foods from different street-vended restaurants. INTERNATIONAL JOURNAL OF ONE HEALTH 2020. [DOI: 10.14202/ijoh.2020.41-48] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Aim: Microbiological risk analysis of ready-to-eat fast foods for sale on the campus of Bangladesh Agricultural University was undertaken to understand the contribution of such foods to foodborne disease.
Materials and Methods: From each of 10 randomly selected fast food outlets, a total of 120 samples of six food items were collected to assess common microbial load. In parallel, vendors were asked about their food production and selling practices, while consumers (n=200) were asked about their consumption of fast foods and whether they had experienced symptoms of foodborne disease.
Results: Aerobic plate count (APC) varied from 6.92 to 7.24 log colony-forming unit (cfu)/g, Staphylococcus spp. 4.67 to 5.15 log cfu/g, Salmonella spp. 3.67 to 4.22 log cfu/g, and Escherichia coli 4.10 to 4.58 log cfu/g. Microbial risk assessment of Staphylococcus spp., Salmonella spp., and E. coli for daily, weekly, or monthly consumption was estimated by Monte Carlo simulation (10,000 iterations). The consumer survey showed 57% chance of being infected by ready-to-eat fast food samples. The calculated mean annual risks of Staphylococcus spp., Salmonella spp., and E. coli infection were about 100% in all cases.
Conclusion: Thus, the study revealed high risk of infection associated with the consumption of ready-to-eat fast foods.
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Affiliation(s)
- Abdullah Al Momen Sabuj
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Zobayda Farzana Haque
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Md. Iftekhar Younus
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Amrita Pondit
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Nanda Barua
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Md. Golzar Hossain
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Md. Alimul Islam
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Sukumar Saha
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
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Younus MI, Sabuj AAM, Haque ZF, Sayem SM, Majumder S, Parvin MS, Islam MA, Saha S. Microbial risk assessment of ready-to-eat mixed vegetable salads from different restaurants of Bangladesh Agricultural University campus. J Adv Vet Anim Res 2020; 7:34-41. [PMID: 32219107 PMCID: PMC7096123 DOI: 10.5455/javar.2020.g390] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 09/30/2019] [Accepted: 10/09/2019] [Indexed: 11/16/2022] Open
Abstract
Objective: The study was aimed to analyze the microbiological quality of mixed vegetable salads and to understand the risk related with its consumption from different restaurants around Bangladesh Agricultural University campus in Mymensingh. Materials and Methods: Sixty (60) samples of mixed vegetable salads were taken from twelve (12) different restaurants in five different time points from each restaurant. In parallel, restaurant workers were asked for handling practices while the consumers were interviewed about their salad consumption pattern and whether they had experienced any health-related problems. Microbial risk assessment of Staphylococcus spp., Salmonella spp., and Escherichia coli was estimated by Monte Carlo simulation (10,000 iterations), an exponential model. Results: Aerobic plate count was ranged from 7.73 ± 0.61 to 9.04 ± 0.26 log cfu/gm, Staphylococcus spp. from 4.64 ± 0.61 to 6.42 ± 0.53 log cfu/gm, Salmonella spp. from 4.75 ± 0.08 to 5.27 ± 0.53 log cfu/gm, and E. coli from 4.98 ± 0.20 to 6.66 ± 0.80 log cfu/gm. From the survey, it was found that total consumers had 18% chances where the male had 13% and the female had 30% chances of being infected with salads. Again frequent, average, and occasional consumers had 31%, 13%, and 0% chances, respectively, of being infected with those salads. From the Monte Carlo simulation, the calculated mean annual risks of Staphylococcus spp., Salmonella spp., and E. coli infection for the three exposure scenarios were found to be about 100%. Conclusion: The study actually revealed the potential microbial contamination in mixed vegetable salads which may impact on food safety and human health. So, the findings suggest that following hygienic measures during processing and handling the microbiological quality of mixed vegetables salads can be improved.
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Affiliation(s)
- Md Iftekhar Younus
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Abdullah Al Momen Sabuj
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Zobayda Farzana Haque
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Sheikh Mohammad Sayem
- Department of Agricultural Statistics, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Shankar Majumder
- Department of Agricultural Statistics, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Mst Sonia Parvin
- Department of Medicine, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Md Alimul Islam
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Sukumar Saha
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
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Reduction in microbial infection risks from raw milk by Electron Beam Technology. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2019.108567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Jeamsripong S, Chase JA, Jay-Russell MT, Buchanan RL, Atwill ER. Experimental In-Field Transfer and Survival of Escherichia coli from Animal Feces to Romaine Lettuce in Salinas Valley, California. Microorganisms 2019; 7:microorganisms7100408. [PMID: 31569566 PMCID: PMC6843402 DOI: 10.3390/microorganisms7100408] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/23/2019] [Accepted: 09/26/2019] [Indexed: 11/20/2022] Open
Abstract
This randomized controlled trial characterized the transfer of E. coli from animal feces and/or furrow water onto adjacent heads of lettuce during foliar irrigation, and the subsequent survival of bacteria on the adaxial surface of lettuce leaves. Two experiments were conducted in Salinas Valley, California: (1) to quantify the transfer of indicator E. coli from chicken and rabbit fecal deposits placed in furrows to surrounding lettuce heads on raised beds, and (2) to quantify the survival of inoculated E. coli on Romaine lettuce over 10 days. E. coli was recovered from 97% (174/180) of lettuce heads to a maximal distance of 162.56 cm (5.33 ft) from feces. Distance from sprinklers to feces, cumulative foliar irrigation, and lettuce being located downwind of the fecal deposit were positively associated, while distance from fecal deposit to lettuce was negatively associated with E. coli transference. E. coli exhibited decimal reduction times of 2.2 and 2.5 days when applied on the adaxial surface of leaves within a chicken or rabbit fecal slurry, respectively. Foliar irrigation can transfer E. coli from feces located in a furrow onto adjacent heads of lettuce, likely due to the kinetic energy of irrigation droplets impacting the fecal surface and/or impacting furrow water contaminated with feces, with the magnitude of E. coli enumerated per head of lettuce influenced by the distance between lettuce and the fecal deposit, cumulative application of foliar irrigation, wind aspect of lettuce relative to feces, and time since final irrigation. Extending the time period between foliar irrigation and harvest, along with a 152.4 cm (5 ft) no-harvest buffer zone when animal fecal material is present, may substantially reduce the level of bacterial contamination on harvested lettuce.
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Affiliation(s)
- Saharuetai Jeamsripong
- Western Center for Food Safety, University of California, Davis, CA 95618, USA (M.T.J.-R.)
- Research Unit in Microbial Food Safety and Antimicrobial Resistance, Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Jennifer A. Chase
- Western Center for Food Safety, University of California, Davis, CA 95618, USA (M.T.J.-R.)
| | - Michele T. Jay-Russell
- Western Center for Food Safety, University of California, Davis, CA 95618, USA (M.T.J.-R.)
| | - Robert L. Buchanan
- Center of Food Safety and Security Systems, College of Agricultural and Natural Resources, University of Maryland, MD 20742, USA;
| | - Edward R. Atwill
- Research Unit in Microbial Food Safety and Antimicrobial Resistance, Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
- Correspondence:
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14
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Assessing the Impact of Cyanuric Acid on Bather’s Risk of Gastrointestinal Illness at Swimming Pools. WATER 2019. [DOI: 10.3390/w11061314] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Current regulatory codes for swimming pool disinfection separately regulate free chlorine (FC) and cyanuric acid (CYA). It is well-known that CYA affects disinfection rates by reversibly binding to FC in aqueous solutions. However, limits for these regulated parameters have neither systematically accounted for this chemistry nor been based on the risk of gastrointestinal illness. This study was intended to determine the minimum concentration of FC relative to CYA based on the risk of gastrointestinal illness from normal fecal sloughing of selected pathogens and to find a simple regulatory rule for jointly managing FC and CYA for consistent disinfection. Literature data on CYA’s effect on microbial inactivation rates were reanalyzed based on the equilibria governing hypochlorous acid (HOCl) concentration. A model was developed that considers the rates of pathogen introduction into pool water, disinfection, turbulent diffusive transport, and pathogen uptake by swimmers to calculate the associated risk of illness. Model results were compared to U.S. Environmental Protection Agency (EPA) untreated recreational water acceptable gastrointestinal illness risk. For Cryptosporidium, correlation between log inactivation and Chick–Watson Ct was far better when C refers to HOCl concentration than to FC (r = −0.96 vs. −0.06). The HOCl concentration had a small variation (± 1.8%) at a constant CYA/FC ratio for typical FC and CYA ranges in swimming pools. In 27 U.S. states, the allowed FC and CYA results in HOCl concentrations spanning more than a factor of 500. Using conservative values for a high bather load pool with 2 mg/L FC and 90 mg/L CYA, the model predicted a 0.071 annual probability of infection for Giardia, exceeding the EPA regulatory 0.036 limit for untreated recreational waters. FC and CYA concentrations in swimming pools should be jointly regulated as a ratio. We recommend a maximum CYA/FC ratio of 20.
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Darlison J, Mieli M, Bengtsson T, Hartmann R, Mogren L, Vågsholm I, Karlsson M, Alsanius BW. Plant species affects establishment of Escherichia coli O157:H7 gfp+ on leafy vegetables. J Appl Microbiol 2019; 127:292-305. [PMID: 31054164 DOI: 10.1111/jam.14299] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 04/18/2019] [Accepted: 04/29/2019] [Indexed: 01/25/2023]
Abstract
AIMS Greenhouse trials were conducted with different cultivars of baby leaf spinach, rocket and Swiss chard and inoculation of Escherichia coli O157:H7 gfp+, to determine whether plant species and cultivar have an impact on the establishment of this strain. METHODS AND RESULTS Three cultivars each of spinach, rocket and Swiss chard were spray inoculated with E. coli O157:H7 gfp+ at doses of log 7 CFU per ml. Due to the different lengths of growing period spinach and Swiss chard were spray inoculated three times and rocket five times, with final inoculation performed 3 days prior to harvest. After a growing period of 26-33 days, E. coli O157:H7 gfp+ was recovered from the leaf surface in mean populations between log 1 and 6 CFU per gram. The lowest occurrence of E. coli O157:H7 gfp+ was found on rocket leaves and the highest on spinach. There was no significant difference in the establishment of E. coli O157:H7 gfp+ between cultivars, but there were differences between plant species. Indigenous phyllosphere bacteria were pure cultured and identified with 16S rRNA gene sequencing. CONCLUSIONS Despite the same high inoculation dose of E. coli O157:H7 gfp+ on leaves, the establishment rate differed between plant species. However, plant cultivar did not affect establishment. Pantoea agglomerans dominated the identified bacterial isolates. SIGNIFICANCE AND IMPACT OF THE STUDY As previous studies are inconclusive on choice of model plant species and cultivar, we studied whether plant species or cultivar determines the fate of E. coli O157:H7 gfp+ on leafy vegetables. The findings indicate that plant species is a key determinant in the establishment of E. coli O157:H7 gfp+.
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Affiliation(s)
- J Darlison
- Department of Biosystems and Technology, Microbial Horticulture Laboratory, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - M Mieli
- Department of Biosystems and Technology, Microbial Horticulture Laboratory, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - T Bengtsson
- Department of Biosystems and Technology, Microbial Horticulture Laboratory, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - R Hartmann
- Department of Biosystems and Technology, Microbial Horticulture Laboratory, Swedish University of Agricultural Sciences, Alnarp, Sweden.,Department of Horticultural Production Systems, Wilhelm Leibniz University, Hannover, Germany
| | - L Mogren
- Department of Biosystems and Technology, Microbial Horticulture Laboratory, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - I Vågsholm
- Department of Biomedical Sciences and Veterinary Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - M Karlsson
- Department of Biosystems and Technology, Microbial Horticulture Laboratory, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - B W Alsanius
- Department of Biosystems and Technology, Microbial Horticulture Laboratory, Swedish University of Agricultural Sciences, Alnarp, Sweden
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16
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Söderqvist K, Rosberg AK, Boqvist S, Alsanius B, Mogren L, Vågsholm I. Season and Species: Two Possible Hurdles for Reducing the Food Safety Risk of Escherichia coli O157 Contamination of Leafy Vegetables. J Food Prot 2019; 82:247-255. [PMID: 30681384 DOI: 10.4315/0362-028x.jfp-18-292] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The food safety risk of Shiga toxin-producing Escherichia coli (STEC) infection per serving of leafy vegetables was investigated using a quantitative microbial risk assessment (QMRA) approach. The estimated level of E. coli O157 contamination was based on observed numbers of Enterobacteriaceae and E. coli on leafy vegetables grown and processed in southern Sweden from 2014 to 2016. Samples were collected before harvest, after washing, and at the end of shelf life. The observed counts were combined with data on the ratio of E. coli to E. coli O157 taken from earlier studies to estimate the probability of illness. The risks of STEC infection associated with species, either spinach ( Spinacia oleracea) or rocket ( Diplotaxis tenuifolia), growing season (spring or autumn), and washing (washed or not washed) were then evaluated. The results indicated that leafy vegetable species and growing season could be possible hurdles for reducing the food safety risk of STEC infection. At harvest, the probability of infection was 87% lower when consuming rocket compared with spinach and 90% lower when consuming leafy vegetables grown in spring compared with autumn. These relative risk reductions remained consistent even with other serving sizes and dose-response models. The lowest risk of STEC infection was associated with leafy vegetables early in the production chain, i.e., before harvest, while the risk increased during storage and processing. Consequently, the highest risk was observed when leafy vegetables were consumed at the end of shelf life. Washing had no effect on the food safety risk of STEC infection in this study. To improve the quality of QMRA, there is a need for additional data on the relationship between indicator organisms that can be easily enumerated (e.g., E. coli and Enterobacteriaceae) and E. coli strains that can cause STEC infection (e.g., E. coli O157) but are difficult to identify in food samples such as leafy vegetables.
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Affiliation(s)
- Karin Söderqvist
- 1 Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7036, SE-750 07 Uppsala, Sweden (ORCID: http://orcid.org/0000-0002-1249-1949 [K.S.])
| | - Anna Karin Rosberg
- 2 Department of Biosystems and Technology, Microbial Horticulture Unit, P.O. Box 103, SE-230 53 Alnarp, Sweden
| | - Sofia Boqvist
- 1 Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7036, SE-750 07 Uppsala, Sweden (ORCID: http://orcid.org/0000-0002-1249-1949 [K.S.])
| | - Beatrix Alsanius
- 2 Department of Biosystems and Technology, Microbial Horticulture Unit, P.O. Box 103, SE-230 53 Alnarp, Sweden
| | - Lars Mogren
- 2 Department of Biosystems and Technology, Microbial Horticulture Unit, P.O. Box 103, SE-230 53 Alnarp, Sweden
| | - Ivar Vågsholm
- 1 Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7036, SE-750 07 Uppsala, Sweden (ORCID: http://orcid.org/0000-0002-1249-1949 [K.S.])
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Lama JK, Bachoon DS. Detection of Brucella suis, Campylobacter jejuni, and Escherichia coli Strains in Feral Pig (Sus scrofa) Communities of Georgia. Vector Borne Zoonotic Dis 2018; 18:350-355. [PMID: 29698123 DOI: 10.1089/vbz.2017.2187] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Feral pigs (Sus scrofa) are an environmentally destructive invasive species that act as a reservoir for zoonotic pathogens. The aim of this study was to determine the presence of Brucella suis, Campylobacter jejuni, and of Escherichia coli in feces of feral pigs from Georgia. Fecal samples were collected from 87 feral pigs from forested and agricultural regions of Georgia. DNA was extracted from the fecal samples and quantitative PCR (qPCR) was used to screen for each of the four pathogens. The qPCR assays indicated that B. suis and eaeA-containing strains of E. coli was present in about 22% and 28% of the samples, respectively. C. jejuni was undetected in any of the feral pig fecal samples. The incidence of B. suis was higher in the pigs from forested region, whereas E. coli strains possessing eaeA gene incidence was higher in the pigs from agricultural regions. In Georgia, feral pigs harbor infectious agents and are a growing threat to the transmission of pathogens to native wildlife, humans, and food crops.
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Affiliation(s)
- Jyoti K Lama
- Department of Biological and Environmental Sciences, Georgia College and State University , Milledgeville, Georgia
| | - Dave S Bachoon
- Department of Biological and Environmental Sciences, Georgia College and State University , Milledgeville, Georgia
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18
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Mishra A, Pang H, Buchanan RL, Schaffner DW, Pradhan AK. A System Model for Understanding the Role of Animal Feces as a Route of Contamination of Leafy Greens before Harvest. Appl Environ Microbiol 2017; 83:e02775-16. [PMID: 27836846 PMCID: PMC5203627 DOI: 10.1128/aem.02775-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 10/30/2016] [Indexed: 11/20/2022] Open
Abstract
The majority of foodborne outbreaks in the United States associated with the consumption of leafy greens contaminated with Escherichia coli O157:H7 have been reported during the period of July to November. A dynamic system model consisting of subsystems and inputs to the system (soil, irrigation, cattle, wild pig, and rainfall) simulating a hypothetical farm was developed. The model assumed two crops of lettuce in a year and simulated planting, irrigation, harvesting, ground preparation for the new crop, contamination of soil and plants, and survival of E. coli O157:H7. As predicted by the baseline model for crops harvested in different months from conventional fields, an estimated 13 out of 257 (5.05%) first crops harvested in July would have at least one plant with at least 1 CFU of E. coli O157:H7. Predictions indicate that no first crops would be contaminated with at least 1 CFU of E. coli O157:H7 for other months (April to June). The maximum E. coli O157:H7 concentration in a plant was higher in the second crop (27.10 CFU) than in the first crop (9.82 CFU). For the second crop, the probabilities of having at least one plant with at least 1 CFU of E. coli O157:H7 in a crop were predicted as 15/228 (6.6%), 5/333 (1.5%), 14/324 (4.3%), and 6/115 (5.2%) in August, September, October, and November, respectively. For organic fields, the probabilities of having at least one plant with ≥1 CFU of E. coli O157:H7 in a crop (3.45%) were predicted to be higher than those for the conventional fields (2.15%). IMPORTANCE This study is the first attempt toward developing a mathematical system model to understand the pathway of E. coli O157:H7 in the production of leafy greens. Results of the presented system model indicate that the seasonality of outbreaks of E. coli O157:H7-associated contamination of leafy greens was in good agreement with the prevalence of this pathogen in cattle and wild pig feces in a major leafy greens-producing region in California. On the basis of comparisons among the results of different scenarios, it can be recommended that the concentration of E. coli O157:H7 in leafy greens can be reduced considerably if contamination of soil with wild pig and cattle feces is mitigated.
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Affiliation(s)
- Abhinav Mishra
- Department of Nutrition and Food Science, University of Maryland, College Park, Maryland, USA
| | - Hao Pang
- Department of Nutrition and Food Science, University of Maryland, College Park, Maryland, USA
| | - Robert L Buchanan
- Department of Nutrition and Food Science, University of Maryland, College Park, Maryland, USA
- Center for Food Safety and Security Systems, University of Maryland, College Park, Maryland, USA
| | - Donald W Schaffner
- Department of Food Science, Rutgers University, New Brunswick, New Jersey, USA
| | - Abani K Pradhan
- Department of Nutrition and Food Science, University of Maryland, College Park, Maryland, USA
- Center for Food Safety and Security Systems, University of Maryland, College Park, Maryland, USA
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19
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Whole cell based microcontact imprinted capacitive biosensor for the detection of Escherichia coli. Biosens Bioelectron 2016; 87:807-815. [PMID: 27657842 DOI: 10.1016/j.bios.2016.08.096] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/26/2016] [Accepted: 08/28/2016] [Indexed: 01/30/2023]
Abstract
In this study, a label-free, selective and sensitive microcontact imprinted capacitive biosensor was developed for the detection of Escherichia coli. The recognition of E. coli was successfully performed by this sensor prepared with the combination of microcontact imprinting method and capacitive biosensor technology. After preparation of bacterial stamps, microcontact-E. coli imprinted gold electrodes were generated using an amino acid based recognition element, N-methacryloyl-L-histidine methylester (MAH), 2-Hydroxyethyl methacrylate (HEMA) as monomers and ethyleneglycol dimethacrylate (EGDMA) as crosslinker under UV-polymerization. Real-time E. coli detection experiments were carried out within the range of 1.0×102-1.0×107CFU/mL. The unique combination of these two techniques provides selective detection with a detection limit of 70CFU/mL. The designed capacitive sensor has high selectivity and was able to distinguish E. coli when present together with competing bacterial strains which are known to have similar shape. In addition, the prepared sensor has the ability to detect E. coli with a recovery of 81-97% in e.g. river water.
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20
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Spencer SEF, Besser TE, Cobbold RN, French NP. 'Super' or just 'above average'? Supershedders and the transmission of Escherichia coli O157:H7 among feedlot cattle. J R Soc Interface 2016; 12:0446. [PMID: 26269231 DOI: 10.1098/rsif.2015.0446] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Supershedders have been suggested to be major drivers of transmission of Escherichia coli O157:H7 (E. coli O157:H7) among cattle in feedlot environments, despite our relatively limited knowledge of the processes that govern periods of high shedding within an individual animal. In this study, we attempt a data-driven approach, estimating the key characteristics of high shedding behaviour, including effects on transmission to other animals, directly from a study of natural E. coli O157:H7 infection of cattle in a research feedlot, in order to develop an evidence-based definition of supershedding. In contrast to the hypothesized role of supershedders, we found that high shedding individuals only modestly increased the risk of transmission: individuals shedding over 10(3) cfu g(-1) faeces were estimated to pose a risk of transmission only 2.45 times greater than those shedding below that level. The data suggested that shedding above 10(3) cfu g(-1) faeces was the most appropriate definition of supershedding behaviour and under this definition supershedding was surprisingly common, with an estimated prevalence of 31.3% in colonized individuals. We found no evidence that environmental contamination by faeces of shedding cattle contributed to transmission over timescales longer than 3 days and preliminary evidence that higher stocking density increased the risk of transmission.
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Affiliation(s)
| | - Thomas E Besser
- Department Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA
| | - Rowland N Cobbold
- School of Veterinary Science, University of Queensland, Gatton, Queensland, Australia 4343
| | - Nigel P French
- mEpiLab, Infectious Disease Research Centre, Institute of Veterinary Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand
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21
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Guo M, Mishra A, Buchanan RL, Dubey JP, Hill DE, Gamble HR, Jones JL, Du X, Pradhan AK. Development of Dose-Response Models to Predict the Relationship for Human Toxoplasma gondii Infection Associated with Meat Consumption. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2016; 36:926-938. [PMID: 26477997 DOI: 10.1111/risa.12500] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Toxoplasma gondii is a protozoan parasite that is responsible for approximately 24% of deaths attributed to foodborne pathogens in the United States. It is thought that a substantial portion of human T. gondii infections is acquired through the consumption of meats. The dose-response relationship for human exposures to T. gondii-infected meat is unknown because no human data are available. The goal of this study was to develop and validate dose-response models based on animal studies, and to compute scaling factors so that animal-derived models can predict T. gondii infection in humans. Relevant studies in literature were collected and appropriate studies were selected based on animal species, stage, genotype of T. gondii, and route of infection. Data were pooled and fitted to four sigmoidal-shaped mathematical models, and model parameters were estimated using maximum likelihood estimation. Data from a mouse study were selected to develop the dose-response relationship. Exponential and beta-Poisson models, which predicted similar responses, were selected as reasonable dose-response models based on their simplicity, biological plausibility, and goodness fit. A confidence interval of the parameter was determined by constructing 10,000 bootstrap samples. Scaling factors were computed by matching the predicted infection cases with the epidemiological data. Mouse-derived models were validated against data for the dose-infection relationship in rats. A human dose-response model was developed as P (d) = 1-exp (-0.0015 × 0.005 × d) or P (d) = 1-(1 + d × 0.003 / 582.414)(-1.479) . Both models predict the human response after consuming T. gondii-infected meats, and provide an enhanced risk characterization in a quantitative microbial risk assessment model for this pathogen.
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Affiliation(s)
- Miao Guo
- Department of Nutrition and Food Science, University of Maryland, College Park, MD, USA
| | - Abhinav Mishra
- Department of Nutrition and Food Science, University of Maryland, College Park, MD, USA
| | - Robert L Buchanan
- Department of Nutrition and Food Science, University of Maryland, College Park, MD, USA
- Center for Food Safety and Security Systems, University of Maryland, College Park, Md, USA
| | - Jitender P Dubey
- U.S. Department of Agriculture, Agricultural Research Service, Beltsville Agriculture Research Center, Animal Parasitic Diseases Laboratory, Beltsville, MD, USA
| | - Dolores E Hill
- U.S. Department of Agriculture, Agricultural Research Service, Beltsville Agriculture Research Center, Animal Parasitic Diseases Laboratory, Beltsville, MD, USA
| | - H Ray Gamble
- National Academy of Sciences, Washington, DC, USA
| | - Jeffrey L Jones
- Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Xianzhi Du
- Department of Electronic and Computer Engineering, University of Maryland, College Park, MD, USA
| | - Abani K Pradhan
- Department of Nutrition and Food Science, University of Maryland, College Park, MD, USA
- Center for Food Safety and Security Systems, University of Maryland, College Park, Md, USA
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22
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Pearson HE, Toribio JALML, Lapidge SJ, Hernández-Jover M. Evaluating the risk of pathogen transmission from wild animals to domestic pigs in Australia. Prev Vet Med 2015; 123:39-51. [PMID: 26711303 DOI: 10.1016/j.prevetmed.2015.11.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 11/26/2015] [Accepted: 11/30/2015] [Indexed: 10/22/2022]
Abstract
Wild animals contribute to endemic infection in livestock as well as the introduction, reintroduction and maintenance of pathogens. The source of introduction of endemic diseases to a piggery is often unknown and the extent of wildlife contribution to such local spread is largely unexplored. The aim of the current study was to quantitatively assess the probability of domestic pigs being exposed to different pathogens from wild animals commonly found around commercial piggeries in Australia. Specifically, this study aims to quantify the probability of exposure to the pathogens Escherichia coli, Salmonella spp. and Campylobacter spp. from European starlings (Sturnus vulgarus); Brachyspira hyodysenteriae, Lawsonia intracellularis and Salmonella spp. from rats (Rattus rattus and Rattus norvegicus); and Mycoplasma hyopneumoniae, Leptospira spp., Brucella suis and L. intracellularis from feral pigs (Sus scrofa). Exposure assessments, using scenario trees and Monte Carlo stochastic simulation modelling, were conducted to identify potential pathways of introduction and calculate the probabilities of these pathways occurring. Input parameters were estimated from a national postal survey of commercial pork producers and from disease detection studies conducted for European starlings, rats and feral pigs in close proximity to commercial piggeries in Australia. Based on the results of the exposure assessments, rats presented the highest probability of exposure of pathogens to domestic pigs at any point in time, and L. intracellularis (median 0.13, 5% and 95%, 0.05-0.23) and B. hyodysenteriae (median 0.10, 0.05-0.19) were the most likely pathogens to be transmitted. Regarding European starlings, the median probability of exposure of domestic pigs to pathogenic E. coli at any point in time was estimated to be 0.03 (0.02-0.04). The highest probability of domestic pig exposure to feral pig pathogens at any point in time was found to be for M. hyopneumoniae (median 0.013, 0.007-0.022) and L. intracellularis (median 0.006, 0.003-0.011) for pigs in free-range piggeries. The sensitivity analysis indicates that the presence and number of wild animals around piggeries, their access to piggeries and pig food and water, and, in the case of feral pigs, their proximity to piggeries, are the most influential parameters on the probability of exposure. Findings from this study support identification of mitigation strategies that could be implemented at on-farm and industry level to minimize the exposure risk from European starlings, rats and feral pigs.
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Affiliation(s)
- Hayley E Pearson
- University of Sydney, Faculty of Veterinary Science, 425 Werombi Rd, Camden, New South Wales 2570, Australia; Invasive Animal Cooperative Research Centre, University of Canberra, ACT 2601, Australia.
| | - Jenny-Ann L M L Toribio
- University of Sydney, Faculty of Veterinary Science, 425 Werombi Rd, Camden, New South Wales 2570, Australia
| | - Steven J Lapidge
- Invasive Animal Cooperative Research Centre, University of Canberra, ACT 2601, Australia; South Australian Research and Development Institute, Plant Research Centre, Waite Campus, 2b Hartley Grove, Urrbrae, South Australia 5064, Australia
| | - Marta Hernández-Jover
- Graham Centre for Agricultural Research (NSW Department of Primary Industries and Charles Sturt University), School of Animal and Veterinary Sciences, Booroma Street, Wagga Wagga, New South Wales 2678, Australia
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23
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Lambertini E, Buchanan RL, Narrod C, Pradhan AK. Transmission of Bacterial Zoonotic Pathogens between Pets and Humans: The Role of Pet Food. Crit Rev Food Sci Nutr 2015; 56:364-418. [DOI: 10.1080/10408398.2014.902356] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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24
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Vogeleer P, Tremblay YDN, Mafu AA, Jacques M, Harel J. Life on the outside: role of biofilms in environmental persistence of Shiga-toxin producing Escherichia coli. Front Microbiol 2014; 5:317. [PMID: 25071733 PMCID: PMC4076661 DOI: 10.3389/fmicb.2014.00317] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 06/10/2014] [Indexed: 11/13/2022] Open
Abstract
Escherichia coli is a heterogeneous species that can be part of the normal flora of humans but also include strains of medical importance. Among pathogenic members, Shiga-toxin producing E. coli (STEC) are some of the more prominent pathogenic E. coli within the public sphere. STEC disease outbreaks are typically associated with contaminated beef, contaminated drinking water, and contaminated fresh produce. These water- and food-borne pathogens usually colonize cattle asymptomatically; cows will shed STEC in their feces and the subsequent fecal contamination of the environment and processing plants is a major concern for food and public safety. This is especially important because STEC can survive for prolonged periods of time outside its host in environments such as water, produce, and farm soil. Biofilms are hypothesized to be important for survival in the environment especially on produce, in rivers, and in processing plants. Several factors involved in biofilm formation such as curli, cellulose, poly-N-acetyl glucosamine, and colanic acid are involved in plant colonization and adherence to different surfaces often found in meat processing plants. In food processing plants, contamination of beef carcasses occurs at different stages of processing and this is often caused by the formation of STEC biofilms on the surface of several pieces of equipment associated with slaughtering and processing. Biofilms protect bacteria against several challenges, including biocides used in industrial processes. STEC biofilms are less sensitive than planktonic cells to several chemical sanitizers such as quaternary ammonium compounds, peroxyacetic acid, and chlorine compounds. Increased resistance to sanitizers by STEC growing in a biofilm is likely to be a source of contamination in the processing plant. This review focuses on the role of biofilm formation by STEC as a means of persistence outside their animal host and factors associated with biofilm formation.
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Affiliation(s)
- Philippe Vogeleer
- Groupe de Recherche sur les Maladies Infectieuses du Porc, Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Centre de Recherche d'Infectiologie Porcine et Avicole, Université de Montréal St-Hyacinthe, QC, Canada
| | - Yannick D N Tremblay
- Groupe de Recherche sur les Maladies Infectieuses du Porc, Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Centre de Recherche d'Infectiologie Porcine et Avicole, Université de Montréal St-Hyacinthe, QC, Canada
| | - Akier A Mafu
- Food Research and Development Centre, Agriculture and Agri-Food Canada St-Hyacinthe, QC, Canada
| | - Mario Jacques
- Groupe de Recherche sur les Maladies Infectieuses du Porc, Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Centre de Recherche d'Infectiologie Porcine et Avicole, Université de Montréal St-Hyacinthe, QC, Canada
| | - Josée Harel
- Groupe de Recherche sur les Maladies Infectieuses du Porc, Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Centre de Recherche d'Infectiologie Porcine et Avicole, Université de Montréal St-Hyacinthe, QC, Canada
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Shiga toxin-producingE. coli(STEC) in swine: prevalence over the finishing period and characteristics of the STEC isolates. Epidemiol Infect 2014; 143:505-14. [DOI: 10.1017/s0950268814001095] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
SUMMARYThis descriptive longitudinal study was conducted to investigate the faecal shedding of Shiga toxin-producingE. coli(STEC) in finishing swine and to characterize the swine STEC isolates that were recovered. Three cohorts of finishing swine (n = 50/cohort; total 150 pigs) were included in the longitudinal study. Individual faecal samples were collected every 2 weeks (8 collections/pig) from the beginning (pig age 10 weeks) to the end (pig age 24 weeks) of the finishing period. STEC isolates were recovered in at least one sample from 65·3% (98/150) of the pigs, and the frequency distribution of first-time STEC detection during the finishing period resembled a point-source outbreak curve. Nineteen O:H serotypes were identified among the STEC isolates. Most STEC isolates (n = 148) belonged to serotype O59:H21 and carried thestx2egene. One O49:H21 STEC isolate carried thestx2eandeaegenes. High prevalence rates of STEC during the finishing period were observed, and STEC isolates in various non-O157 serogroups were recovered. These data enhance understanding of swine STEC epidemiology, and future research is needed to confirm whether or not swine STEC are of public health concern.
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Zhao Y, Aarnink AJA, De Jong MCM, Groot Koerkamp PWG. Airborne Microorganisms From Livestock Production Systems and Their Relation to Dust. CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY 2014; 44:1071-1128. [PMID: 32288664 PMCID: PMC7113898 DOI: 10.1080/10643389.2012.746064] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Large amounts of airborne microorganisms are emitted from livestock production. These emitted microorganisms may associate with dust, and are suspected to pose a risk of airborne infection to humans in vicinity and to animals on other farms. However, the extent to which airborne transmission may play a role in the epidemic, and how dust acts as a carrier of microorganisms in the transmission processes is unknown. The authors present the current knowledge of the entire process of airborne transmission of microorganisms-from suspension and transportation until deposition and infection-and their relation to dust. The sampling and the mitigation techniques of airborne microorganisms and dust in livestock production systems are introduced as well.
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Affiliation(s)
- Yang Zhao
- Wageningen UR Livestock Research, Lelystad, the Netherlands
- Department of Agricultural and Biosystems EngineeringIowa State University, Ames, IA, USA
| | | | - Mart C. M. De Jong
- Quantitative Veterinary Epidemiology, Wageningen University, Wageningen, the Netherlands
| | - Peter W. G. Groot Koerkamp
- Wageningen UR Livestock Research, Lelystad, the Netherlands
- Farm Technology Group, Wageningen University, Wageningen, the Netherlands
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Abstract
Shiga toxin-producing Escherichia coli (STEC) strains are food-borne pathogens that are an important public health concern. STEC infection is associated with severe clinical diseases in human beings, including hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS), which can lead to kidney failure and death. Cattle are the most important STEC reservoir. However, a number of STEC outbreaks and HUS cases have been attributed to pork products. In swine, STEC strains are known to be associated with edema disease. Nevertheless, the relationship between STEC of swine origin and human illness has yet to be determined. This review critically summarizes epidemiologic and biological studies of swine STEC. Several epidemiologic studies conducted in multiple regions of the world have demonstrated that domestic swine can carry and shed STEC. Moreover, animal studies have demonstrated that swine are susceptible to STEC O157:H7 infection and can shed the bacterium for 2 months. A limited number of molecular epidemiologic studies, however, have provided conflicting evidence regarding the relationship between swine STEC and human illness. The role that swine play in STEC transmission to people and the contribution to human disease frequency requires further evaluation.
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Belda-Galbis CM, Pina-Pérez MC, Leufvén A, Martínez A, Rodrigo D. Impact assessment of carvacrol and citral effect on Escherichia coli K12 and Listeria innocua growth. Food Control 2013. [DOI: 10.1016/j.foodcont.2013.03.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Draft Genome sequence of Escherichia coli AI27, a porcine isolate belonging to phylogenetic group B1. J Bacteriol 2012; 194:6640-1. [PMID: 23144394 DOI: 10.1128/jb.01749-12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli AI27 is a putatively commensal strain isolated from feces of a pig. Here we report the draft genome sequence of E. coli AI27. This is the first porcine strain in the phylogenetic group B1 whose genome sequence has been determined.
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Fernandez-Brando RJ, Miliwebsky E, Mejías MP, Baschkier A, Panek CA, Abrey-Recalde MJ, Cabrera G, Ramos MV, Rivas M, Palermo MS. Shiga toxin-producing Escherichia coli O157 : H7 shows an increased pathogenicity in mice after the passage through the gastrointestinal tract of the same host. J Med Microbiol 2012; 61:852-859. [DOI: 10.1099/jmm.0.041251-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Romina J. Fernandez-Brando
- División Inmunología, Instituto de Medicina Experimental (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Elizabeth Miliwebsky
- Servicio Fisiopatogenia, Instituto Nacional de Enfermedades Infecciosas – ANLIS ‘Dr Carlos G. Malbrán’, Buenos Aires, Argentina
| | - María Pilar Mejías
- División Inmunología, Instituto de Medicina Experimental (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Ariela Baschkier
- Servicio Fisiopatogenia, Instituto Nacional de Enfermedades Infecciosas – ANLIS ‘Dr Carlos G. Malbrán’, Buenos Aires, Argentina
| | - Cecilia A. Panek
- División Inmunología, Instituto de Medicina Experimental (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - María Jimena Abrey-Recalde
- División Inmunología, Instituto de Medicina Experimental (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Gabriel Cabrera
- División Inmunología, Instituto de Medicina Experimental (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - María Victoria Ramos
- División Inmunología, Instituto de Medicina Experimental (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Marta Rivas
- Servicio Fisiopatogenia, Instituto Nacional de Enfermedades Infecciosas – ANLIS ‘Dr Carlos G. Malbrán’, Buenos Aires, Argentina
| | - Marina S. Palermo
- División Inmunología, Instituto de Medicina Experimental (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
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Intraspecies variation in the emergence of hyperinfectious bacterial strains in nature. PLoS Pathog 2012; 8:e1002647. [PMID: 22511871 PMCID: PMC3325197 DOI: 10.1371/journal.ppat.1002647] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Accepted: 03/01/2012] [Indexed: 12/29/2022] Open
Abstract
Salmonella is a principal health concern because of its endemic prevalence in food and water supplies, the rise in incidence of multi-drug resistant strains, and the emergence of new strains associated with increased disease severity. Insights into pathogen emergence have come from animal-passage studies wherein virulence is often increased during infection. However, these studies did not address the prospect that a select subset of strains undergo a pronounced increase in virulence during the infective process- a prospect that has significant implications for human and animal health. Our findings indicate that the capacity to become hypervirulent (100-fold decreased LD50) was much more evident in certain S. enterica strains than others. Hyperinfectious salmonellae were among the most virulent of this species; restricted to certain serotypes; and more capable of killing vaccinated animals. Such strains exhibited rapid (and rapidly reversible) switching to a less-virulent state accompanied by more competitive growth ex vivo that may contribute to maintenance in nature. The hypervirulent phenotype was associated with increased microbial pathogenicity (colonization; cytotoxin production; cytocidal activity), coupled with an altered innate immune cytokine response within infected cells (IFN-β; IL-1β; IL-6; IL-10). Gene expression analysis revealed that hyperinfectious strains display altered transcription of genes within the PhoP/PhoQ, PhoR/PhoB and ArgR regulons, conferring changes in the expression of classical virulence functions (e.g., SPI-1; SPI-2 effectors) and those involved in cellular physiology/metabolism (nutrient/acid stress). As hyperinfectious strains pose a potential risk to human and animal health, efforts toward mitigation of these potential food-borne contaminants may avert negative public health impacts and industry-associated losses. Salmonellosis continues to compromise human health, animal welfare, and modern agriculture. Developing a comprehensive control plan requires an understanding of how pathogens emerge and express traits that confer increased incidence and severity of disease. It is well-established that animal passage often results in increased virulence; however, our findings indicate that the capacity to undergo a pronounced increase in virulence after passage was much more prevalent in certain Salmonella isolates than in others. The resultant hyperinfectious strains are among the most virulent salmonellae reported; were restricted to certain serotypes; and were able to override the immunity conferred in vaccinated animals. The induction of hypervirulence was responsive to subtle changes in environmental conditions and, potentially, may occur in other salmonellae serotypes after passage through certain hosts and/or exposure to certain environmental variables; a response that may be common across the microbial realm. Thus, management practices and environmental conditions inherent to livestock production have the potential to inadvertently trigger hypervirulence (e.g., diet; herd size; exposure to livestock waste and/or antimicrobials). From a farm management perspective, careful consideration must be given to risk-management strategies that reduce emergence/persistence of these potential food-borne contaminants to safeguard public health and reduce industry-associated losses.
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Jay-Russell MT, Bates A, Harden L, Miller WG, Mandrell RE. Isolation of Campylobacter from Feral Swine (Sus scrofa) on the Ranch Associated with the 2006 Escherichia coli O157:H7 Spinach Outbreak Investigation in California. Zoonoses Public Health 2012; 59:314-9. [DOI: 10.1111/j.1863-2378.2012.01465.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Andraud M, Rose N, Laurentie M, Sanders P, Le Roux A, Cariolet R, Chauvin C, Jouy E. Estimation of transmission parameters of a fluoroquinolone-resistant Escherichia coli strain between pigs in experimental conditions. Vet Res 2011; 42:44. [PMID: 21366902 PMCID: PMC3053234 DOI: 10.1186/1297-9716-42-44] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 03/02/2011] [Indexed: 12/03/2022] Open
Abstract
Antimicrobial resistance is of primary importance regarding public and animal health issues. Persistence and spread of resistant strains within a population contribute to the maintenance of a reservoir and lead to treatment failure. An experimental trial was carried out to study the horizontal transmission of a fluoroquinolone-resistant Escherichia coli strain from inoculated to naïve pigs. All naïve contact pigs had positive counts of fluoroquinolone-resistant E. coli after only two days of contact. Moreover, re-infections of inoculated pigs caused by newly contaminated animals were suspected. A maximum likelihood method, based on a susceptible-infectious-susceptible (SIS) model, was used to determine the transmission parameters. Two transmission levels were identified depending on the quantity of bacteria shed by infected individuals: (i) low-shedders with bacterial counts of resistant E. coli in the faeces between 5*103 and 106 CFU/g (βL = 0.41 [0.27; 0.62]), (ii) high shedders with bacterial counts above 106 CFU/g (βH = 0.98 [0.59; 1.62]). Hence, transmission between animals could be pivotal in explaining the persistence of resistant bacteria within pig herds.
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Affiliation(s)
- Mathieu Andraud
- Anses, Fougères laboratory, BP 90203, F-35302 Fougères Cedex, France.
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Ferens WA, Hovde CJ. Escherichia coli O157:H7: animal reservoir and sources of human infection. Foodborne Pathog Dis 2010; 8:465-87. [PMID: 21117940 DOI: 10.1089/fpd.2010.0673] [Citation(s) in RCA: 357] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
This review surveys the literature on carriage and transmission of enterohemorrhagic Escherichia coli (EHEC) O157:H7 in the context of virulence factors and sampling/culture technique. EHEC of the O157:H7 serotype are worldwide zoonotic pathogens responsible for the majority of severe cases of human EHEC disease. EHEC O157:H7 strains are carried primarily by healthy cattle and other ruminants, but most of the bovine strains are not transmitted to people, and do not exhibit virulence factors associated with human disease. Prevalence of EHEC O157:H7 is probably underestimated. Carriage of EHEC O157:H7 by individual animals is typically short-lived, but pen and farm prevalence of specific isolates may extend for months or years and some carriers, designated as supershedders, may harbor high intestinal numbers of the pathogen for extended periods. The prevalence of EHEC O157:H7 in cattle peaks in the summer and is higher in postweaned calves and heifers than in younger and older animals. Virulent strains of EHEC O157:H7 are rarely harbored by pigs or chickens, but are found in turkeys. The bacteria rarely occur in wildlife with the exception of deer and are only sporadically carried by domestic animals and synanthropic rodents and birds. EHEC O157:H7 occur in amphibian, fish, and invertebrate carriers, and can colonize plant surfaces and tissues via attachment mechanisms different from those mediating intestinal attachment. Strains of EHEC O157:H7 exhibit high genetic variability but typically a small number of genetic types predominate in groups of cattle and a farm environment. Transmission to people occurs primarily via ingestion of inadequately processed contaminated food or water and less frequently through contact with manure, animals, or infected people.
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Affiliation(s)
- Witold A Ferens
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, Idaho 83844-3052, USA.
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Soller JA, Schoen ME, Bartrand T, Ravenscroft JE, Ashbolt NJ. Estimated human health risks from exposure to recreational waters impacted by human and non-human sources of faecal contamination. WATER RESEARCH 2010; 44:4674-91. [PMID: 20656314 DOI: 10.1016/j.watres.2010.06.049] [Citation(s) in RCA: 299] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Revised: 06/17/2010] [Accepted: 06/21/2010] [Indexed: 05/20/2023]
Abstract
This work was conducted to determine whether estimated risks following exposure to recreational waters impacted by gull, chicken, pig, or cattle faecal contamination are substantially different than those associated with waters impacted by human sources such as treated wastewater. Previously published Quantitative Microbial Risk Assessment (QMRA) methods were employed and extended to meet these objectives. Health outcomes used in the analyses were infection from reference waterborne pathogens via ingestion during recreation and subsequent gastrointestinal (GI) illness. Illness risks from these pathogens were calculated for exposure to faecally contaminated recreational water at the U.S. regulatory limits of 35 cfu 100 mL(-1) enterococci and 126 cfu 100 mL(-1)Escherichia coli. The probabilities of GI illness were calculated using pathogen dose-response relationships from the literature and Monte Carlo simulations. Three scenarios were simulated, representing a range of feasible interpretations of the available data. The primary findings are that: 1) GI illness risks associated with exposure to recreational waters impacted by fresh cattle faeces may not be substantially different from waters impacted by human sources; and 2) the risks associated with exposure to recreational waters impacted by fresh gull, chicken, or pig faeces appear substantially lower than waters impacted by human sources. These results suggest that careful consideration may be needed in the future for the management of recreational waters not impacted by human sources.
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Affiliation(s)
- Jeffrey A Soller
- Soller Environmental, LLC, 3022 King St, Berkeley, CA 94703, USA.
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Sánchez S, Martínez R, García A, Vidal D, Blanco J, Blanco M, Blanco J, Mora A, Herrera-León S, Echeita A, Alonso J, Rey J. Detection and characterisation of O157:H7 and non-O157 Shiga toxin-producing Escherichia coli in wild boars. Vet Microbiol 2010; 143:420-3. [DOI: 10.1016/j.vetmic.2009.11.016] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 11/09/2009] [Accepted: 11/12/2009] [Indexed: 11/26/2022]
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Cornick NA. Tylosin and chlorotetracycline decrease the duration of fecal shedding of E. coli O157:H7 by swine. Vet Microbiol 2010; 143:417-9. [DOI: 10.1016/j.vetmic.2009.11.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Revised: 11/05/2009] [Accepted: 11/10/2009] [Indexed: 10/20/2022]
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Cernicchiaro N, Pearl D, Ghimire S, Gyles C, Johnson R, LeJeune J, Ziebell K, McEwen S. Risk factors associated with Escherichia coli O157:H7 in Ontario beef cow–calf operations. Prev Vet Med 2009; 92:106-15. [DOI: 10.1016/j.prevetmed.2009.07.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Revised: 07/15/2009] [Accepted: 07/20/2009] [Indexed: 12/18/2022]
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Jay MT, Cooley M, Carychao D, Wiscomb GW, Sweitzer RA, Crawford-Miksza L, Farrar JA, Lau DK, O'Connell J, Millington A, Asmundson RV, Atwill ER, Mandrell RE. Escherichia coli O157:H7 in feral swine near spinach fields and cattle, central California coast. Emerg Infect Dis 2008; 13:1908-11. [PMID: 18258044 PMCID: PMC2876768 DOI: 10.3201/eid1312.070763] [Citation(s) in RCA: 317] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We investigated involvement of feral swine in contamination of agricultural fields and surface waterways with Escherichia coli O157:H7 after a nationwide outbreak traced to bagged spinach from California. Isolates from feral swine, cattle, surface water, sediment, and soil at 1 ranch were matched to the outbreak strain.
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Affiliation(s)
- Michele T Jay
- California Department of Public Health, Richmond, California, USA.
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Indirect transmission of Escherichia coli O157:H7 occurs readily among swine but not among sheep. Appl Environ Microbiol 2008; 74:2488-91. [PMID: 18310419 DOI: 10.1128/aem.02897-07] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transmission of Escherichia coli O157:H7 among reservoir animals is generally thought to occur either by direct contact between a naïve animal and an infected animal or by consumption of food or water containing the organism. Although ruminants are considered the major reservoir, there are two reports of human infections caused by E. coli O157:H7 linked to the consumption of pork products or to the contamination of fresh produce by swine manure. The objective of this study was to determine whether E. coli O157:H7 could be transmitted to naïve animals, both sheep and swine, that did not have any direct contact with an infected donor animal. We recovered E. coli O157:H7 from 10/10 pigs with nose-to-nose contact with the infected donor or animals adjacent to the donor and from 5/6 naïve pigs that were penned in the same room as the donor pig but 10 to 20 ft away. In contrast, when the experiment was repeated with sheep, E. coli O157:H7 was recovered from 4/6 animals that had nose-to-nose contact with the infected donor or adjacent animals and from 0/6 naïve animals penned 10 to 20 ft away from the donor. These results suggest that E. coli O157:H7 is readily transmitted among swine and that transmission can occur by the creation of contaminated aerosols.
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Oporto B, Esteban JI, Aduriz G, Juste RA, Hurtado A. Escherichia coli O157:H7 and Non-O157 Shiga Toxin-producing E. coli in Healthy Cattle, Sheep and Swine Herds in Northern Spain. Zoonoses Public Health 2008; 55:73-81. [DOI: 10.1111/j.1863-2378.2007.01080.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Butler SM, Nelson EJ, Chowdhury N, Faruque SM, Calderwood SB, Camilli A. Cholera stool bacteria repress chemotaxis to increase infectivity. Mol Microbiol 2006; 60:417-26. [PMID: 16573690 PMCID: PMC2754204 DOI: 10.1111/j.1365-2958.2006.05096.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Factors that enhance the transmission of pathogens are poorly understood. We show that Vibrio cholerae shed in human 'rice-water' stools have a 10-fold lower oral infectious dose in an animal model than in vitro grown V. cholerae, which may aid in transmission during outbreaks. Furthermore, we identify a bacterial factor contributing to this enhanced infectivity: The achievement of a transient motile but chemotaxis-defective state upon shedding from humans. Rice-water stool V. cholerae have reduced levels of CheW-1, which is essential for chemotaxis, and were consequently shown to have a chemotaxis defect when tested in capillary assays. Through mutational analyses, such a state is known to enhance the infectivity of V. cholerae. This is the first report of a pathogen altering its chemotactic state in response to human infection in order to enhance its transmission.
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Affiliation(s)
- Susan M. Butler
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Eric J. Nelson
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Nityananda Chowdhury
- International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka 1212, Bangladesh
| | - Shah M. Faruque
- International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka 1212, Bangladesh
| | - Stephen B. Calderwood
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, and Harvard Medical School, Boston, MA 02115, USA
| | - Andrew Camilli
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
- Howard Hughes Medical Institute, 136 Harrison Avenue, Boston, MA 02111, USA
- For correspondence. E-mail ; Tel. (+1) 617 636 2144; Fax (+1) 617 636 2175
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Dowd SE, Ishizaki H. Microarray based comparison of two Escherichia coli O157:H7 lineages. BMC Microbiol 2006; 6:30. [PMID: 16539702 PMCID: PMC1431545 DOI: 10.1186/1471-2180-6-30] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2006] [Accepted: 03/15/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Previous research has identified the potential for the existence of two separate lineages of Escherichia coli O157:H7. Clinical isolates tended to cluster primarily within one of these two lineages. To determine if there are virulence related genes differentially expressed between the two lineages we chose to utilize microarray technology to perform an initial screening. RESULTS Using a 610 gene microarray, designed against the E. coli O157 EDL 933 transcriptome, targeting primarily virulence systems, we chose 3 representative Lineage I isolates (LI groups mostly clinical isolates) and 3 representative Lineage II isolates (LII groups mostly bovine isolates). Using standard dye swap experimental designs, statistically different expression (P < 0.05) of 73 genes between the two lineages was revealed. Result highlights indicate that under in vitro anaerobic growth conditions, there is up-regulation of stx2b, ureD, curli (csgAFEG), and stress related genes (hslJ, cspG, ibpB, ibpA) in Lineage I, which may contribute to enhanced virulence or transmission potential. Lineage II exhibits significant up-regulation of type III secretion apparatus, LPS, and flagella related transcripts. CONCLUSION These results give insight into comparative regulation of virulence genes as well as providing directions for future research. Ultimately, evaluating the expression of key virulence factors among different E. coli O157 isolates has inherent value and the interpretation of such expression data will continue to evolve as our understanding of virulence, pathogenesis and transmission improves.
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Affiliation(s)
- Scot E Dowd
- Livestock Issues Research Unit, USDA-ARS, Lubbock, TX, USA
| | - Hiroshi Ishizaki
- Department of Grazing Animal Production, National Institute of Livestock and Grassland Science, Nasushiobara, Tochigi 329-2793, Japan
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Sonntag AK, Bielaszewska M, Mellmann A, Dierksen N, Schierack P, Wieler LH, Schmidt MA, Karch H. Shiga toxin 2e-producing Escherichia coli isolates from humans and pigs differ in their virulence profiles and interactions with intestinal epithelial cells. Appl Environ Microbiol 2006; 71:8855-63. [PMID: 16332882 PMCID: PMC1317431 DOI: 10.1128/aem.71.12.8855-8863.2005] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Thirteen Escherichia coli strains harboring stx2e were isolated from 11,056 human stools. This frequency corresponded to the presence of the stx2e allele in 1.7% of all Shiga toxin-producing E. coli (STEC) strains. The strains harboring stx2e were associated with mild diarrhea (n = 9) or asymptomatic infections (n = 4). Because STEC isolates possessing stx2e are porcine pathogens, we compared the human STEC isolates with stx2e-harboring E. coli isolated from piglets with edema disease and postweaning diarrhea. All pig isolates possessed the gene encoding the F18 adhesin, and the majority possessed adhesin involved in diffuse adherence; these adhesins were absent from all the human STEC isolates. In contrast, the high-pathogenicity island encoding an iron uptake system was found only in human isolates. Host-specific patterns of interaction with intestinal epithelial cells were observed. All human isolates adhered to human intestinal epithelial cell lines T84 and HCT-8 but not to pig intestinal epithelial cell line IPEC-J2. In contrast, the pig isolates completely lysed human epithelial cells but not IPEC-J2 cells, to which most of them adhered. Our data demonstrate that E. coli isolates producing Shiga toxin 2e have imported specific virulence and fitness determinants which allow them to adapt to the specific hosts in which they cause various forms of disease.
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Affiliation(s)
- Anne-Katharina Sonntag
- Institute of Hygiene and the National Consulting Laboratory on Hemolytic Uremic Syndrome, University Hospital Münster, Robert Koch Str. 41, Münster, Germany
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Wiles S, Dougan G, Frankel G. Emergence of a 'hyperinfectious' bacterial state after passage of Citrobacter rodentium through the host gastrointestinal tract. Cell Microbiol 2005; 7:1163-72. [PMID: 16008583 DOI: 10.1111/j.1462-5822.2005.00544.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Citrobacter rodentium belongs to a family of human and animal enteric pathogens that includes the clinically significant enterohaemorrhagic Escherichia coli (EHEC) and enteropathogenic E. coli (EPEC). These pathogens exploit attaching and effacing (A/E) lesions to colonize the host gastrointestinal tract. However, both EHEC and EPEC are poorly pathogenic in mice. In contrast, C. rodentium, which is genetically highly related to E. coli, relies on A/E lesion formation as an essential step in both colonization and infection of the murine mucosa, providing an excellent in vivo model. In this study we have used bioluminescence imaging (BLI) to investigate the organ specificity and dynamics of colonization of mice by LB-grown and mouse-passaged C. rodentium in situ and in real time. We have demonstrated the appearance of a 'hyperinfectious' state after passage of C. rodentium through the murine gastrointestinal tract. The 'hyperinfectious' state was found to dramatically reduce the dose required to infect secondary individuals, and also influenced the tissue distribution of colonizing bacteria, removing the requirement for primary colonization of the caecal patch. In addition, the 'hyperinfectious' phenotype was found to be transient with one overnight passage in rich medium sufficient to return C. rodentium to 'culture' infectivity.
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Affiliation(s)
- Siouxsie Wiles
- Centre for Molecular Microbiology and Infection, Department of Biological Sciences, Imperial College London, London SW7 2AZ, UK
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Best A, La Ragione RM, Clifford D, Cooley WA, Sayers AR, Woodward MJ. A comparison of Shiga-toxin negative Escherichia coli O157 aflagellate and intimin deficient mutants in porcine in vitro and in vivo models of infection. Vet Microbiol 2005; 113:63-72. [PMID: 16337755 DOI: 10.1016/j.vetmic.2005.10.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2005] [Revised: 10/12/2005] [Accepted: 10/18/2005] [Indexed: 02/06/2023]
Abstract
Isolation of Shiga-toxin (Stx) positive Escherichia coli O157:H7 from commercially grown pigs has been reported. Furthermore, experimental infection studies have demonstrated that Stx-positive E. coli O157:H7 can persist in 12-week-old experimentally orally inoculated conventional pigs for up to 2 months and that persistence was not dependent upon intimin. We have shown that the flagellum of Stx-negative E. coli O157:H7 does not have a role to play in pathogenesis in ruminant models whereas, in poultry, the flagellum of E. coli O157:H7 was important for long-term persistent infection. The contribution of the flagellum of Stx-negative E. coli O157 in the colonisation of pigs was investigated by adherence assays on a porcine (IPI-21) cell line, porcine in vitro organ culture (IVOC) and experimental oral inoculation of conventional 14-week-old pigs. E. coli O157:H7 NCTC12900nal(r) and isogenic aflagellate and intimin deficient mutants adhered equally well to IPI-21 cells. In porcine IVOC association assays, E. coli O157:H7 NCTC12900nal(r) was associated in significantly higher numbers to tissues from the caecum and the terminal rectum than other sites. The aflagellate and intimin deficient mutants significantly adhered in greater numbers to more IVOC gastrointestinal tissues than the parent. Groups of 14-week-old pigs were dosed orally with 10(10)CFU/10ml of either E. coli O157:H7 NCTC12900nal(r) or isogenic aflagellate and intimin deficient mutants and recovery of each test strain was similar. Histological analysis of pig tissues at post mortem examination revealed that E. coli O157 specifically stained bacteria were associated with the mucosa of the ascending and spiral colon. These data suggest that colonisation and persistence of Stx-negative E. coli O157:H7 in pigs, involves mechanisms that do not require the flagellum or intimin.
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Affiliation(s)
- Angus Best
- Department of Food and Environmental Safety, Veterinary Laboratories Agency (Weybridge), Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, UK.
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Grant MA. Comparison of a new enrichment procedure for Shiga toxin-producing Escherichia coli with five standard methods. J Food Prot 2005; 68:1593-9. [PMID: 21132965 DOI: 10.4315/0362-028x-68.8.1593] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A new procedure for enrichment of Escherichia coli O157:H7 and other Shiga toxin-producing E. coli was compared to five standard methods: the British Public Health Laboratory Service, International Standard Method, U.S. Department of Agriculture, Canadian Health Products and Food Branch, and U.S. Food and Drug Administration. The new procedure was comparable to the standard methods in its ability to detect target cells inoculated into foods at approximately 1 CFU g(-1). Comparisons were also made of the ability of the six enrichment procedures to detect E. coli O157:H7 against a large background of competitor microorganisms. In these experiments the new procedure yielded more target cells than the other five enrichments by two to three orders of magnitude as determined by enumeration on sorbitol MacConkey agar with tellurite and cefixime and Rainbow agar with tellurite and novobiocin and by verification of presumptive colonies by real-time PCR. For example, the population of enterohemorrhagic E. coli strain 6341 recovered on sorbitol MacConkey agar with tellurite and cefixime after enrichment with the experimental method was 2.42 x 10(8) CFU ml(-1) and 1.80 x 10(6) CFU ml(-1) after enrichment with the Canadian Health Products and Food Branch method, the second most effective in this experiment. In addition, broth cultures resulting from each of the six enrichment procedures were used to prepare templates for real-time PCR detection of stx1/stx2. Resulting threshold cycle (Ct) values after the experimental enrichment were similar to positive control values, whereas the five standard methods produced delayed Ct values or were not detected.
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Affiliation(s)
- Michael A Grant
- U.S. Food and Drug Administration, Pacific Regional Laboratory Northwest, 23rd Drive S.E., Bothell, Washington 98021, USA.
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