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Wang X, Yu D, Chui L, Zhou T, Feng Y, Cao Y, Zhi S. A Comprehensive Review on Shiga Toxin Subtypes and Their Niche-Related Distribution Characteristics in Shiga-Toxin-Producing E. coli and Other Bacterial Hosts. Microorganisms 2024; 12:687. [PMID: 38674631 PMCID: PMC11052178 DOI: 10.3390/microorganisms12040687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 03/25/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024] Open
Abstract
Shiga toxin (Stx), the main virulence factor of Shiga-toxin-producing E. coli (STEC), was first discovered in Shigella dysenteriae strains. While several other bacterial species have since been reported to produce Stx, STEC poses the most significant risk to human health due to its widespread prevalence across various animal hosts that have close contact with human populations. Based on its biochemical and molecular characteristics, Shiga toxin can be grouped into two types, Stx1 and Stx2, among which a variety of variants and subtypes have been identified in various bacteria and host species. Interestingly, the different Stx subtypes appear to vary in their host distribution characteristics and in the severity of diseases that they are associated with. As such, this review provides a comprehensive overview on the bacterial species that have been recorded to possess stx genes to date, with a specific focus on the various Stx subtype variants discovered in STEC, their prevalence in certain host species, and their disease-related characteristics. This review provides a better understanding of the Stx subtypes and highlights the need for rapid and accurate approaches to toxin subtyping for the proper evaluation of the health risks associated with Shiga-toxin-related bacterial food contamination and human infections.
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Affiliation(s)
- Xuan Wang
- School of Public Health, Ningbo University, Ningbo 315000, China; (X.W.); (T.Z.); (Y.F.)
| | - Daniel Yu
- School of Public Health, Univeristy of Alberta, Edmonton, AB T6G 2R3, Canada;
| | - Linda Chui
- Alberta Precision Laboratories-ProvLab, Edmonton, AB T6G 2J2, Canada;
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2B7, Canada
| | - Tiantian Zhou
- School of Public Health, Ningbo University, Ningbo 315000, China; (X.W.); (T.Z.); (Y.F.)
| | - Yu Feng
- School of Public Health, Ningbo University, Ningbo 315000, China; (X.W.); (T.Z.); (Y.F.)
| | - Yuhao Cao
- School of Basic Medical Sciences, Ningbo University, Ningbo 315000, China;
| | - Shuai Zhi
- School of Public Health, Ningbo University, Ningbo 315000, China; (X.W.); (T.Z.); (Y.F.)
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Thomas GA, Paradell Gil T, Müller CT, Rogers HJ, Berger CN. From field to plate: How do bacterial enteric pathogens interact with ready-to-eat fruit and vegetables, causing disease outbreaks? Food Microbiol 2024; 117:104389. [PMID: 37919001 DOI: 10.1016/j.fm.2023.104389] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 09/11/2023] [Accepted: 09/17/2023] [Indexed: 11/04/2023]
Abstract
Ready-to-eat fruit and vegetables are a convenient source of nutrients and fibre for consumers, and are generally safe to eat, but are vulnerable to contamination with human enteric bacterial pathogens. Over the last decade, Salmonella spp., pathogenic Escherichia coli, and Listeria monocytogenes have been linked to most of the bacterial outbreaks of foodborne illness associated with fresh produce. The origins of these outbreaks have been traced to multiple sources of contamination from pre-harvest (soil, seeds, irrigation water, domestic and wild animal faecal matter) or post-harvest operations (storage, preparation and packaging). These pathogens have developed multiple processes for successful attachment, survival and colonization conferring them the ability to adapt to multiple environments. However, these processes differ across bacterial strains from the same species, and across different plant species or cultivars. In a competitive environment, additional risk factors are the plant microbiome phyllosphere and the plant responses; both factors directly modulate the survival of the pathogens on the leaf's surface. Understanding the mechanisms involved in bacterial attachment to, colonization of, and proliferation, on fresh produce and the role of the plant in resisting bacterial contamination is therefore crucial to reducing future outbreaks.
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Affiliation(s)
- Gareth A Thomas
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Teresa Paradell Gil
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Carsten T Müller
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Hilary J Rogers
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Cedric N Berger
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK.
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Carter MQ, Quiñones B, Laniohan N, Carychao D, Pham A, He X, Cooley M. Pathogenicity assessment of Shiga toxin-producing Escherichia coli strains isolated from wild birds in a major agricultural region in California. Front Microbiol 2023; 14:1214081. [PMID: 37822735 PMCID: PMC10562709 DOI: 10.3389/fmicb.2023.1214081] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 09/11/2023] [Indexed: 10/13/2023] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) consists of diverse strains differing in genetic make-up and virulence potential. To better understand the pathogenicity potential of STEC carried by the wildlife, three STEC and one E. coli strains isolated from wild birds near a major agricultural region in California were selected for comparative pathogenomic analyses. Three American crow (Corvus brachyrhynchos) strains, RM9088, RM9513, and RM10410, belonging to phylogroup A with serotypes O109:H48, O9:H30, and O113:H4, respectively, and a red-winged blackbird (Agelaius phoeniceus) strain RM14516 in phylogroup D with serotype O17:H18, were examined. Shiga toxin genes were identified in RM9088 (stx1a), RM10410 (stx1a + stx2d), and RM14516 (stx2a). Unlike STEC O157:H7 strain EDL933, none of the avian STEC strains harbored the pathogenicity islands OI-122, OI-57, and the locus of enterocyte effacement, therefore the type III secretion system biogenesis genes and related effector genes were absent in the three avian STEC genomes. Interestingly, all avian STEC strains exhibited greater (RM9088 and RM14516) or comparable (RM10410) cytotoxicity levels compared with EDL933. Comparative pathogenomic analyses revealed that RM9088 harbored numerous genes encoding toxins, toxins delivery systems, and adherence factors, including heat-labile enterotoxin, serine protease autotransporter toxin Pic, type VI secretion systems, protein adhesin Paa, fimbrial adhesin K88, and colonization factor antigen I. RM9088 also harbored a 36-Kb high pathogenicity island, which is related to iron acquisition and pathogenicity in Yersinia spp. Strain RM14516 carried an acid fitness island like the one in EDL933, containing a nine gene cluster involved in iron acquisition. Genes encoding extracellular serine protease EspP, subtilase cytotoxin, F1C fimbriae, and inverse autotransporter adhesin IatC were only detected in RM14516, and genes encoding serine protease autotransporter EspI and P fimbriae were only identified in RM10410. Although all curli genes were present in avian STEC strains, production of curli fimbriae was only detected for RM9088 and RM14516. Consistently, strong, moderate, and little biofilms were observed for RM9088, RM14516, and RM10410, respectively. Our study revealed novel combinations of virulence factors in two avian strains, which exhibited high level of cytotoxicity and strong biofilm formation. Comparative pathogenomics is powerful in assessing pathogenicity and health risk of STEC strains.
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Affiliation(s)
- Michelle Qiu Carter
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Beatriz Quiñones
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Nicole Laniohan
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Diana Carychao
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Antares Pham
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Xiaohua He
- Foodborne Toxin Detection and Prevention Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Michael Cooley
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
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Bereznicka A, Mikolajczyk K, Szymczak-Kulus K, Kapczynska K, Majorczyk E, Modlinska A, Piasecki T, Kaczmarek R, Czerwinski M. Two Paralogous Gb3/CD77 Synthases in Birds Show Different Preferences for Their Glycoprotein and Glycosphingolipid Substrates. Int J Mol Sci 2021; 22:9761. [PMID: 34575935 PMCID: PMC8466213 DOI: 10.3390/ijms22189761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/06/2021] [Accepted: 09/06/2021] [Indexed: 11/22/2022] Open
Abstract
Most glycosyltransferases show remarkable gross and fine substrate specificity, which is reflected in the old one enzyme-one linkage paradigm. While human Gb3/CD77 synthase is a glycosyltransferase that synthesizes the Galα1→4Gal moiety mainly on glycosphingolipids, its pigeon homolog prefers glycoproteins as acceptors. In this study, we characterized two Gb3/CD77 synthase paralogs found in pigeons (Columba livia). We evaluated their specificities in transfected human teratocarcinoma 2102Ep cells by flow cytofluorometry, Western blotting, high-performance thin-layer chromatography, mass spectrometry and metabolic labelling with 14C-galactose. We found that the previously described pigeon Gb3/CD77 synthase (called P) can use predominately glycoproteins as acceptors, while its paralog (called M), which we serendipitously discovered while conducting this study, efficiently synthesizes Galα1→4Gal caps on both glycoproteins and glycosphingolipids. These two paralogs may underlie the difference in expression profiles of Galα1→4Gal-terminated glycoconjugates between neoavians and mammals.
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Affiliation(s)
- Anna Bereznicka
- Laboratory of Glycobiology, Department of Immunochemistry, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wroclaw, Poland; (A.B.); (K.M.); (K.S.-K.); (R.K.)
| | - Krzysztof Mikolajczyk
- Laboratory of Glycobiology, Department of Immunochemistry, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wroclaw, Poland; (A.B.); (K.M.); (K.S.-K.); (R.K.)
| | - Katarzyna Szymczak-Kulus
- Laboratory of Glycobiology, Department of Immunochemistry, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wroclaw, Poland; (A.B.); (K.M.); (K.S.-K.); (R.K.)
| | - Katarzyna Kapczynska
- Laboratory of Medical Microbiology, Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wroclaw, Poland;
| | - Edyta Majorczyk
- Faculty of Physical Education and Physiotherapy, Opole University of Technology, 45-758 Opole, Poland;
| | - Anna Modlinska
- Department of Epizootiology and Clinic of Birds and Exotic Animals, Wroclaw University of Environmental Sciences, 50-366 Wroclaw, Poland; (A.M.); (T.P.)
| | - Tomasz Piasecki
- Department of Epizootiology and Clinic of Birds and Exotic Animals, Wroclaw University of Environmental Sciences, 50-366 Wroclaw, Poland; (A.M.); (T.P.)
| | - Radoslaw Kaczmarek
- Laboratory of Glycobiology, Department of Immunochemistry, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wroclaw, Poland; (A.B.); (K.M.); (K.S.-K.); (R.K.)
| | - Marcin Czerwinski
- Laboratory of Glycobiology, Department of Immunochemistry, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wroclaw, Poland; (A.B.); (K.M.); (K.S.-K.); (R.K.)
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Nowaczek A, Dec M, Stępień-Pyśniak D, Urban-Chmiel R, Marek A, Różański P. Antibiotic Resistance and Virulence Profiles of Escherichia coli Strains Isolated from Wild Birds in Poland. Pathogens 2021; 10:1059. [PMID: 34451523 PMCID: PMC8400592 DOI: 10.3390/pathogens10081059] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/09/2021] [Accepted: 08/17/2021] [Indexed: 11/16/2022] Open
Abstract
Wild animals are increasingly reported as carriers of antibiotic-resistant and pathogenic bacteria including Enterobacteriaceae. However, the role of free-living birds as reservoirs for potentially dangerous microbes is not yet thoroughly understood. In our work, we examined Escherichia coli strains from wild birds in Poland in relation to their antimicrobial agents susceptibility, virulence and phylogenetic affiliation. Identification of E. coli was performed using MALDI-TOF mass spectrometry. The antibiotic susceptibility of the isolates was determined by the broth microdilution method, and resistance and virulence genes were detected by PCR. E. coli bacteria were isolated from 32 of 34 samples. The strains were most often classified into phylogenetic groups B1 (50%) and A (25%). Resistance to tetracycline (50%), ciprofloxacin (46.8%), gentamicin (34.3%) and ampicillin (28.1%) was most frequently reported, and as many as 31.2% of E. coli isolates exhibited a multidrug resistance phenotype. Among resistance genes, sul2 (31.2% of isolates) and blaTEM (28.1%) were identified most frequently, while irp-2 (31.2%) and ompT (28.1%) were the most common virulence-associated genes. Five strains were included in the APEC group. The study indicates that wild birds can be carriers of potentially dangerous E. coli strains and vectors for the spread of resistant bacteria and resistance determinants in the environment.
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Affiliation(s)
- Anna Nowaczek
- Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Akademicka 12, 20-033 Lublin, Poland; (A.N.); (D.S.-P.); (R.U.-C.); (A.M.)
| | - Marta Dec
- Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Akademicka 12, 20-033 Lublin, Poland; (A.N.); (D.S.-P.); (R.U.-C.); (A.M.)
| | - Dagmara Stępień-Pyśniak
- Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Akademicka 12, 20-033 Lublin, Poland; (A.N.); (D.S.-P.); (R.U.-C.); (A.M.)
| | - Renata Urban-Chmiel
- Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Akademicka 12, 20-033 Lublin, Poland; (A.N.); (D.S.-P.); (R.U.-C.); (A.M.)
| | - Agnieszka Marek
- Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Akademicka 12, 20-033 Lublin, Poland; (A.N.); (D.S.-P.); (R.U.-C.); (A.M.)
| | - Paweł Różański
- Department of Animal Hygiene and Environmental Hazards, Faculty of Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland;
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Hubálek Z. Pathogenic microorganisms associated with gulls and terns (Laridae). JOURNAL OF VERTEBRATE BIOLOGY 2021. [DOI: 10.25225/jvb.21009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Zdeněk Hubálek
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic; e-mail:
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Jordan DW, Gehring TM, Seefelt NE, Alm EW. Use of Great Lakes Recreational Beaches and Human-Waste Sites by Ring-Billed Gulls. Northeast Nat (Steuben) 2021. [DOI: 10.1656/045.028.0202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Dustin W. Jordan
- Department of Biology and Institute for Great Lakes Research, Central Michigan University, Mount Pleasant, MI 48859
| | - Thomas M. Gehring
- Department of Biology and Institute for Great Lakes Research, Central Michigan University, Mount Pleasant, MI 48859
| | - Nancy E. Seefelt
- Department of Biology and Institute for Great Lakes Research, Central Michigan University, Mount Pleasant, MI 48859
| | - Elizabeth W. Alm
- Department of Biology and Institute for Great Lakes Research, Central Michigan University, Mount Pleasant, MI 48859
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Evaluation of a hybrid in-field sampling method for the detection of pathogenic bacteria through consideration of a priori knowledge of factors related to non-random contamination. Food Microbiol 2020; 89:103412. [DOI: 10.1016/j.fm.2020.103412] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 12/20/2019] [Accepted: 01/02/2020] [Indexed: 11/21/2022]
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Generalizability and comparability of prevalence estimates in the wild bird literature: methodological and epidemiological considerations. Anim Health Res Rev 2020; 21:89-95. [PMID: 32066515 DOI: 10.1017/s1466252320000043] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Wild birds have been the focus of a great deal of research investigating the epidemiology of zoonotic bacteria and antimicrobial resistance in the environment. While enteric pathogens (e.g. Campylobacter, Salmonella, and E. coli O157:H7) and antimicrobial resistant bacteria of public health importance have been isolated from a wide variety of wild bird species, there is a considerable variation in the measured prevalence of a given microorganism from different studies. This variation may often reflect differences in certain ecological and biological factors such as feeding habits and immune status. Variation in prevalence estimates may also reflect differences in sample collection and processing methods, along with a host of epidemiological inputs related to overall study design. Because the generalizability and comparability of prevalence estimates in the wild bird literature are constrained by their methodological and epidemiological underpinnings, understanding them is crucial to the accurate interpretation of prevalence estimates. The main purpose of this review is to examine methodological and epidemiological inputs to prevalence estimates in the wild bird literature that have a major bearing on their generalizability and comparability. The inputs examined here include sample type, microbiological methods, study design, bias, sample size, definitions of prevalence outcomes and parameters, and control of clustering. The issues raised in this review suggest, among other things, that future prevalence studies of wild birds should avoid opportunistic sampling when possible, as this places significant limitations on the generalizability of prevalence data.
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Obayomi O, Bernstein N, Edelstein M, Vonshak A, Ghazayarn L, Ben-Hur M, Tebbe CC, Gillor O. Importance of soil texture to the fate of pathogens introduced by irrigation with treated wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 653:886-896. [PMID: 30759614 DOI: 10.1016/j.scitotenv.2018.10.378] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 10/27/2018] [Accepted: 10/27/2018] [Indexed: 06/09/2023]
Abstract
World-wide water scarcity is urging the use of treated wastewater (TWW) for irrigation but this practice may have adverse effects on soil and crop contamination due to the introduction of potential microbial pathogens. The objective of this study was to evaluate the potential health risks caused by TWW irrigation of soils differing in their texture, i.e., soil particle fractions including sand, silt and clay. We predicted that the presence of fecal indicator bacteria (FIB) and pathogens would not be linked to TWW irrigation, yet their abundance would be favored by the smallest soil fraction (~2 nm, e.g., clay) as it provides the largest surface area. To test our hypotheses, culture dependent and independent techniques were used to monitor the presence, abundance and source of FIB and microbial pathogens (bacteria and protists) in water (TWW and potable water) and three irrigated soil types (clay, loam and loamy-sand) in a field study spanning two years. The results showed that FIB and pathogens' abundance were significantly different between water types, yet these differences did not carry to the irrigated soils. The abundance and presence of FIB and potential opportunistic or obligate human pathogens did not significantly differ (p > 0.05) between TWW and potable water irrigated soils. Moreover, the source of the FIB and potential pathogens could not be linked to irrigation with TWW. Yet, soil type significantly altered the potential pathogens' diversity (p < 0.05) and abundance (p < 0.05), and differences were affected by clay content, as predicted. The results gave no indication for potential adverse health effects associated with the application of TWW but demonstrated that clay has a particular stabilizing effect on the potential presence of microbial pathogens.
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Affiliation(s)
- Olabiyi Obayomi
- Zuckerberg Institute for Water Research, J. Blaustein Institutes for Desert Research, Ben Gurion University, Midreshet Ben Gurion 84990, Israel
| | - Nirit Bernstein
- Institute of Soil Water and Environmental Sciences, Volcani Center, POB 6, Bet-Dagan 50-250, Israel
| | - Menahem Edelstein
- Department of Vegetable Crops, Agricultural Research Organization (ARO), Newe Ya'ar Research Center, P. O. Box 1021, Ramat Yishay 30095, Israel
| | - Ahuva Vonshak
- Zuckerberg Institute for Water Research, J. Blaustein Institutes for Desert Research, Ben Gurion University, Midreshet Ben Gurion 84990, Israel
| | - Lusine Ghazayarn
- Zuckerberg Institute for Water Research, J. Blaustein Institutes for Desert Research, Ben Gurion University, Midreshet Ben Gurion 84990, Israel
| | - Meni Ben-Hur
- Institute of Soil Water and Environmental Sciences, Volcani Center, POB 6, Bet-Dagan 50-250, Israel
| | - Christoph C Tebbe
- Thünen Institute of Biodiversity, Bundesallee 65, 38116 Braunschweig, Germany
| | - Osnat Gillor
- Zuckerberg Institute for Water Research, J. Blaustein Institutes for Desert Research, Ben Gurion University, Midreshet Ben Gurion 84990, Israel.
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Optical Parameters for Using Visible-Wavelength Reflectance or Fluorescence Imaging to Detect Bird Excrements in Produce Fields. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9040715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Consumption of produce contaminated with pathogens of fecal origin is the most common source of food borne illnesses. Current practice is to visually survey fields for evidence of fecal contamination, and to exclude problematic areas from harvest. Bird excrement is known to contain human pathogens, and is often not detectable in produce fields using current survey methods. The goal of this project was to identify parameters for optical detection of bird excrements to support development of instruments to be used to supplement existing visual surveys. Under daylight ambient conditions, results suggested that reflectance imaging at around 500–530 nm or 610–640 nm could be used to detect excrements from the three bird species tested. Images were acquired using ad hoc camera parameters; however, normalizing intensities for individual images at 525 nm and using a fixed detection threshold allowed detection of 100% of bird excrements with no false positives against the background that consisted of local soil and fresh romaine and spinach leaves. Similar results were obtained using fluorescence imaging. Fluorescent imaging was accomplished in a darkened room using 405-nm illumination. The largest consistent differences in intensity responses between excrements and the brightest non-excrement object in the background matrix occurred at around 550 nm. Results suggested that using reflectance or fluorescence imaging for detection of bird excrements could be a valuable tool for reducing risks of consuming contaminated produce. One possibility would be to incorporate appropriate reflectance imaging capabilities in drones under the control of the individuals currently conducting field surveys.
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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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Najdenski H, Dimova T, Zaharieva MM, Nikolov B, Petrova-Dinkova G, Dalakchieva S, Popov K, Hristova-Nikolova I, Zehtindjiev P, Peev S, Trifonova-Hristova A, Carniel E, Panferova YA, Tokarevich NK. Migratory birds along the Mediterranean – Black Sea Flyway as carriers of zoonotic pathogens. Can J Microbiol 2018; 64:915-924. [DOI: 10.1139/cjm-2017-0763] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
At the crossroad between Europe, Asia, and Africa, Bulgaria is part of the Mediterranean – Black Sea Flyway (MBSF) used by millions of migratory birds. In this study, bird species migrating through Bulgaria were investigated as carriers of zoonotic pathogens. In total, 706 birds belonging to 46 species were checked for the presence of various bacterial pathogens (Campylobacter, Yersinia, Salmonella, Listeria, Escherichia coli, Staphylococcus aureus, Francisella tularensis, Coxiella burnetii, Borrelia burgdorferi, and Brucella spp.). From 673 birds we investigated fecal samples, from the remaining 33, blood samples. We detected Campylobacter 16S rDNA gene in 1.3% of birds, but none were of pathogenic Campylobacter jejuni and Campylobacter coli species. Escherichia coli 16S rDNA gene was found in 8.8% of the birds. Out of 34 birds that transported Yersinia enterocolitica strains (5.05%), only 1 carried a pathogenic isolate. Three birds (0.4%) were carriers of nonpathogenic Salmonella strains. Four avian samples (0.6%) were positive for Listeria monocytogenes and 1 (0.15%) was positive for Brucella spp. None of the birds tested carried the tick-borne pathogens C. burnetii or B. burgdorferi sensu lato. Antibiotic-resistant strains were detected, suggesting that migratory birds could be reservoirs and spreaders of bacterial pathogens as well as antibiotic resistance genes.
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Affiliation(s)
- Hristo Najdenski
- Department of Infectious Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 26 Acad. Georgi Bonchev Str., 1113, Sofia, Bulgaria
| | - Tanya Dimova
- Department of Immunobiology of Reproduction, Institute of Biology and Immunology of Reproduction, Bulgarian Academy of Sciences, 73 Tzarigradsko shose, 1113, Sofia, Bulgaria
| | - Maya M. Zaharieva
- Department of Infectious Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 26 Acad. Georgi Bonchev Str., 1113, Sofia, Bulgaria
| | - Boris Nikolov
- Department of Animal Diversity and Resources, Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria
| | - Gergana Petrova-Dinkova
- Department of Animal Diversity and Resources, Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria
| | - Svetla Dalakchieva
- Department of Animal Diversity and Resources, Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria
| | - Konstantin Popov
- Department of Animal Diversity and Resources, Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria
| | - Iva Hristova-Nikolova
- Department of Animal Diversity and Resources, Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria
| | - Pavel Zehtindjiev
- Department of Animal Diversity and Resources, Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria
| | - Strahil Peev
- Department of Animal Diversity and Resources, Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria
| | - Anetka Trifonova-Hristova
- Department of Biology and Pathology, National Research Station of Game Management, 1113, Sofia, Bulgaria
| | - Elisabeth Carniel
- Yersinia Research Unit and National Reference Laboratory, Institut Pasteur, 28 rue du Docteur Roux, 75015, Paris, France
| | - Yulia A. Panferova
- Laboratory of Zooanthroponotic Infections, St. Petersburg Pasteur Institute, 14 Mira str., 197101, St. Petersburg, Russia
| | - Nikolay K. Tokarevich
- Laboratory of Zooanthroponotic Infections, St. Petersburg Pasteur Institute, 14 Mira str., 197101, St. Petersburg, Russia
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14
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Alegbeleye OO, Singleton I, Sant'Ana AS. Sources and contamination routes of microbial pathogens to fresh produce during field cultivation: A review. Food Microbiol 2018; 73:177-208. [PMID: 29526204 PMCID: PMC7127387 DOI: 10.1016/j.fm.2018.01.003] [Citation(s) in RCA: 252] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 12/31/2017] [Accepted: 01/02/2018] [Indexed: 12/17/2022]
Abstract
Foodborne illness resulting from the consumption of contaminated fresh produce is a common phenomenon and has severe effects on human health together with severe economic and social impacts. The implications of foodborne diseases associated with fresh produce have urged research into the numerous ways and mechanisms through which pathogens may gain access to produce, thereby compromising microbiological safety. This review provides a background on the various sources and pathways through which pathogenic bacteria contaminate fresh produce; the survival and proliferation of pathogens on fresh produce while growing and potential methods to reduce microbial contamination before harvest. Some of the established bacterial contamination sources include contaminated manure, irrigation water, soil, livestock/ wildlife, and numerous factors influence the incidence, fate, transport, survival and proliferation of pathogens in the wide variety of sources where they are found. Once pathogenic bacteria have been introduced into the growing environment, they can colonize and persist on fresh produce using a variety of mechanisms. Overall, microbiological hazards are significant; therefore, ways to reduce sources of contamination and a deeper understanding of pathogen survival and growth on fresh produce in the field are required to reduce risk to human health and the associated economic consequences.
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Affiliation(s)
| | - Ian Singleton
- School of Applied Sciences, Sighthill Campus, Edinburgh Napier University, Edinburgh, UK
| | - Anderson S Sant'Ana
- Department of Food Science, Faculty of Food Engineering, University of Campinas, Campinas, São Paulo, Brazil.
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15
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Lopes E, Cardoso W, Nishi D, Horn R, Albuquerque Á, Lima S, Beleza A, Gaio F, Carmo C, Pascoal Filho M, Teixeira R. Serogroup identification, phenotypic detection of hemolysis and extended spectrum beta-lactamases of Escherichia coli isolated from psittacine of illegal wildlife trade in Fortaleza, Brazil. ARQ BRAS MED VET ZOO 2018. [DOI: 10.1590/1678-4162-9369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
ABSTRACT This study aimed to identify serogroups of Escherichia coli important for human health in isolates from psittacine of illegal wildlife trade in Ceará State. In addition, hemolysis and production of Extended Spectrum Beta-Lactamases (ESBL) was assessed in the isolates. A total of 78 E. coli strains isolated from different Psittaciformes species from a wildlife rehabilitation center in Fortaleza, Brazil. The isolates used in this study were previously identified and stored. Serogroup identification was performed using polyvalent sera for EPEC (O55, O111, O119, O114, O125, O86, O126, O127, O128), EIEC (O136, O124) and EHEC (O157). ESBL detection was performed with double disk synergy method. For hemolysis detection, isolates were inoculated in blood agar base enriched with ovine blood. Only 31 (39.7%) isolates were seropositive and the most frequent were O127, O114, O128 and O111. There was no agglutination for serogroups O55, O124, O136 or O157. Considering both seropositive and seronegative isolates, 9 (11.5%) and 35 (44.9%) presented hemolysis and ESBL production, respectively. In conclusion, the investigated psittacine from illegal wildlife trade hosted ESBL-producing E. coli strains and some belong to important serogroups often linked to severe human infections.
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Affiliation(s)
| | | | | | - R.V. Horn
- Universidade Estadual do Ceará, Brazil
| | | | | | | | - F.C. Gaio
- Universidade Estadual do Ceará, Brazil
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16
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Litt PK, Jaroni D. Isolation and Physiomorphological Characterization of Escherichia coli O157:H7-Infecting Bacteriophages Recovered from Beef Cattle Operations. Int J Microbiol 2017; 2017:7013236. [PMID: 29123549 PMCID: PMC5662819 DOI: 10.1155/2017/7013236] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 08/30/2017] [Indexed: 11/18/2022] Open
Abstract
Bacteriophages, recovered from beef cattle environment and specifically targeting Escherichia coli O157:H7, were examined for their physiological and morphological characteristics. Degree of bacterial lysis and host range of isolated bacteriophages was determined against 55 isolates of E. coli O157:H7. Morphology of phages was examined under transmission electron microscope. Phage growth parameters, particularly rate of adsorption, rise period, latent period, and burst size were also determined. The stability of isolated phages was tested at acidic and alkaline pH, at high temperatures, and in cold storage. A total of 7 phages were isolated which showed lytic activity against 50 out of 55 isolates of E. coli O157:H7. Based on the morphology, phages were classified into Myoviridae or Siphoviridae family. Phages had a rise period between 19 and 40 min, a short latent period between 12 and 30 min, and a large burst size (89-631 virions per infected cell), indicating high lytic activity. Phages remained stable for 24 h at a wide pH (1-11) and temperature range (40-60°C) and for 90 d in cold storage. Characterization of bacteriophages, with a diverse host range of E. coli O157:H7, could aid in the development of effective biocontrol strategies for this pathogen in the food industry.
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Affiliation(s)
- Pushpinder Kaur Litt
- Department of Animal Science and Food and Agricultural Products Center, Oklahoma State University, 148 FAPC, Monroe St., Stillwater, OK 74078, USA
| | - Divya Jaroni
- Department of Animal Science and Food and Agricultural Products Center, Oklahoma State University, 148 FAPC, Monroe St., Stillwater, OK 74078, USA
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17
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Wu B, Wang XC, Dzakpasu M. Genetic characterization of fecal impacts of seagull migration on an urban scenery lake. WATER RESEARCH 2017; 117:27-36. [PMID: 28364653 DOI: 10.1016/j.watres.2017.03.041] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 03/17/2017] [Accepted: 03/18/2017] [Indexed: 06/07/2023]
Abstract
A microbial source tracking scheme was devised to differentiate fecal impacts of seagulls from that of human activities on an urban scenery lake in southern China, which is a major wintering ground for the black-headed seagull. Fecal contamination of seagulls was characterized by quantifying a novel genetic marker targeting Catellicoccus marimamalium. Quantification of this marker was combined with those of Escherichia coli, human-associated Bacteroidales, thermophilic Campylobacter and Helicobacter. Findings of a year-round study indicate that C. marimamalium levels correlated strongly, both spatially and temporally, with seagull migration. A steady increase in C. marimammalium concentrations was recorded between October 2014 and March 2015, which peaked at about 5-log copies/100 mL in January. However, a background level of about 2.1-log copies/100 mL was noticeable from April through September when seagulls were absent, probably due to other host sources or secondary habitats for C. marimammalium. Seagull migration also caused an apparent elevation of E. coli concentrations (86% and 60%, respectively for qPCR and culture method; p < 0.001) as well as Campylobacter and Helicobacter (66% and 68%, respectively; p < 0.001). Nonetheless, in contrast to the declining levels of E. coli, Campylobacter and Helicobacter, the human-specific Bacteroidales marginally increased in the seagull-absent season, indicating a limited influence of human activities, compared with seagull migration, on the seasonal variations in microbial water quality of the lake. The elevated levels of FIB, Campylobacter and Helicobacter along with C. marimammalium may imply human health risk of the lake water due to seasonal seagull migration, which requires further investigation for risk assessment.
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Affiliation(s)
- Baolei Wu
- International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Key Lab of Environmental Engineering, Engineering Technology Research Center for Wastewater Treatment and Reuse, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13, Yanta Road, Xi'an, Shaanxi, 710055, PR China
| | - Xiaochang C Wang
- International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Key Lab of Environmental Engineering, Engineering Technology Research Center for Wastewater Treatment and Reuse, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13, Yanta Road, Xi'an, Shaanxi, 710055, PR China.
| | - Mawuli Dzakpasu
- International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Key Lab of Environmental Engineering, Engineering Technology Research Center for Wastewater Treatment and Reuse, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13, Yanta Road, Xi'an, Shaanxi, 710055, PR China
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18
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Highmore CJ, Rothwell SD, Keevil CW. Improved sample preparation for direct quantitative detection of Escherichia coli O157 in soil using qPCR without pre-enrichment. Microb Biotechnol 2017; 10:969-976. [PMID: 28585286 PMCID: PMC5481516 DOI: 10.1111/1751-7915.12737] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 04/29/2017] [Indexed: 12/01/2022] Open
Abstract
The prominence of fresh produce as a vehicle for foodborne pathogens such as enterohaemorrhagic Escherichia coli (EHEC) O157 is rising, where disease cases can cause hospitalization and in some cases death. This rise emphasises the necessity for accurate and sensitive methods for detection of pathogens in soil, potential sources of contamination of fresh produce. The complexity of the soil matrix has previously proven prohibitive to pathogen detection via molecular methods without the use of a culture enrichment step, thereby excluding the detection of viable but non-culturable cells. Here, a sample preparation procedure to facilitate a direct qPCR assay is developed for the detection of E. coli O157 in soil, bypassing culture steps in favour of sample separation through pulsification release and filtration. In sand and peat-based compost, the method is sensitive to 10 CFU g-1 soil. When testing soils from agricultural sites, it was found that several were qPCR positive for E. coli O157 while being culture-negative, with peat-based compost possessing a concentration of 200 tir gene copies per gram. This procedure offers a rapid, quantitative assessment of the potential presence of E. coli O157 in soils which can act as a prescreen of their suitability to grow fresh produce safely.
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Affiliation(s)
- Callum J Highmore
- Environmental Healthcare Unit, Faculty of Natural & Environmental Sciences, University of Southampton, Southampton, UK, SO17 1BJ
| | - Steve D Rothwell
- Vitacress Salads Ltd, Lower Link Farm, St Mary Bourne, Andover, UK, SP11 6DB
| | - Charles W Keevil
- Environmental Healthcare Unit, Faculty of Natural & Environmental Sciences, University of Southampton, Southampton, UK, SO17 1BJ
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19
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Gutierrez ME, Janes ME, Torrico DD, Carabante KM, Prinyawiwatkul W. Assessment of the ability of five culture media for the detection of
E
scherichia coli
O157. Int J Food Sci Technol 2016. [DOI: 10.1111/ijfs.13164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Myriam E. Gutierrez
- School of Nutrition and Food Sciences Louisiana State University Agricultural Center Baton Rouge LA 70803 USA
| | - Marlene E. Janes
- School of Nutrition and Food Sciences Louisiana State University Agricultural Center Baton Rouge LA 70803 USA
| | - Damir D. Torrico
- Faculty of Veterinary and Agricultural Sciences, Food and Wine Science The University of Melbourne Parkville 3055 Vic. Australia
| | - Kennet M. Carabante
- School of Nutrition and Food Sciences Louisiana State University Agricultural Center Baton Rouge LA 70803 USA
| | - Witoon Prinyawiwatkul
- School of Nutrition and Food Sciences Louisiana State University Agricultural Center Baton Rouge LA 70803 USA
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20
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Ahmed W, Harwood VJ, Nguyen K, Young S, Hamilton K, Toze S. Utility of Helicobacter spp. associated GFD markers for detecting avian fecal pollution in natural waters of two continents. WATER RESEARCH 2016; 88:613-622. [PMID: 26562798 DOI: 10.1016/j.watres.2015.10.050] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 10/18/2015] [Accepted: 10/26/2015] [Indexed: 06/05/2023]
Abstract
Avian fecal droppings may negatively impact environmental water quality due to the presence of high concentrations of fecal indicator bacteria (FIB) and zoonotic pathogens. This study was aimed at evaluating the performance characteristics and utility of a Helicobacter spp. associated GFD marker by screening 265 fecal and wastewater samples from a range of avian and non-avian host groups from two continents (Brisbane, Australia and Florida, USA). The host-prevalence and -specificity of this marker among fecal and wastewater samples tested from Brisbane were 0.58 and 0.94 (maximum value of 1.00). These values for the Florida fecal samples were 0.30 (host-prevalence) and 1.00 (host-specificity). The concentrations of the GFD markers in avian and non-avian fecal nucleic acid samples were measured at a test concentration of 10 ng of nucleic acid at Brisbane and Florida laboratories using the quantitative PCR (qPCR) assay. The mean concentrations of the GFD marker in avian fecal nucleic acid samples (5.2 × 10(3) gene copies) were two orders of magnitude higher than non-avian fecal nucleic acid samples (8.6 × 10(1) gene copies). The utility of this marker was evaluated by testing water samples from the Brisbane River, Brisbane and a freshwater creek in Florida. Among the 18 water samples tested from the Brisbane River, 83% (n = 18) were positive for the GFD marker, and the concentrations ranged from 6.0 × 10(1)-3.2 × 10(2) gene copies per 100 mL water. In all, 92% (n = 25) water samples from the freshwater creek in Florida were also positive for the GFD marker with concentrations ranging from 2.8 × 10(1)-1.3 × 10(4) gene copies per 100 mL water. Based on the results, it can be concluded that the GFD marker is highly specific to avian host groups, and could be used as a reliable marker to detect the presence and amount of avian fecal pollution in environmental waters.
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Affiliation(s)
- W Ahmed
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Qld 4102, Australia; Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore, DC, Qld 4558, Australia.
| | - V J Harwood
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA
| | - K Nguyen
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA
| | - S Young
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA
| | - K Hamilton
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Qld 4102, Australia; Department of Civil, Architectural, and Environmental Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104, USA
| | - S Toze
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Qld 4102, Australia; School of Population Health, University of Queensland, Herston Road, Qld 4006, Australia
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21
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Devane ML, Wood D, Chappell A, Robson B, Webster-Brown J, Gilpin BJ. Identifying avian sources of faecal contamination using sterol analysis. ENVIRONMENTAL MONITORING AND ASSESSMENT 2015; 187:625. [PMID: 26370196 DOI: 10.1007/s10661-015-4800-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 08/12/2015] [Indexed: 06/05/2023]
Abstract
Discrimination of the source of faecal pollution in water bodies is an important step in the assessment and mitigation of public health risk. One tool for faecal source tracking is the analysis of faecal sterols which are present in faeces of animals in a range of distinctive ratios. Published ratios are able to discriminate between human and herbivore mammal faecal inputs but are of less value for identifying pollution from wildfowl, which can be a common cause of elevated bacterial indicators in rivers and streams. In this study, the sterol profiles of 50 avian-derived faecal specimens (seagulls, ducks and chickens) were examined alongside those of 57 ruminant faeces and previously published sterol profiles of human wastewater, chicken effluent and animal meatwork effluent. Two novel sterol ratios were identified as specific to avian faecal scats, which, when incorporated into a decision tree with human and herbivore mammal indicative ratios, were able to identify sterols from avian-polluted waterways. For samples where the sterol profile was not consistent with herbivore mammal or human pollution, avian pollution is indicated when the ratio of 24-ethylcholestanol/(24-ethylcholestanol + 24-ethylcoprostanol + 24-ethylepicoprostanol) is ≥0.4 (avian ratio 1) and the ratio of cholestanol/(cholestanol + coprostanol + epicoprostanol) is ≥0.5 (avian ratio 2). When avian pollution is indicated, further confirmation by targeted PCR specific markers can be employed if greater confidence in the pollution source is required. A 66% concordance between sterol ratios and current avian PCR markers was achieved when 56 water samples from polluted waterways were analysed.
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Affiliation(s)
- Megan L Devane
- Institute of Environmental Science and Research Limited, Christchurch Science Centre, PO Box 29-181, Christchurch, New Zealand.
| | - David Wood
- Institute of Environmental Science and Research Limited, Christchurch Science Centre, PO Box 29-181, Christchurch, New Zealand
| | - Andrew Chappell
- Institute of Environmental Science and Research Limited, Christchurch Science Centre, PO Box 29-181, Christchurch, New Zealand
| | - Beth Robson
- Institute of Environmental Science and Research Limited, Christchurch Science Centre, PO Box 29-181, Christchurch, New Zealand
| | - Jenny Webster-Brown
- Waterways Centre for Freshwater Management, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Brent J Gilpin
- Institute of Environmental Science and Research Limited, Christchurch Science Centre, PO Box 29-181, Christchurch, New Zealand
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22
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Esameili H, Khanjari A, Gholami F. Detection and characterization of Escherichia coli O157:H7 from feral pigeon in Qom province, Iran. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2015. [DOI: 10.1016/s2222-1808(14)60637-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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23
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Abstract
ABSTRACT
Shiga toxin-producing
Escherichia coli
(STEC) strains have been detected in a wide diversity of mammals, birds, fish, and several insects. Carriage by most animals is asymptomatic, thus allowing for dissemination of the bacterium in the environment without detection. Replication of the organism may occur in the gastrointestinal tract of some animals, notably ruminants. Carriage may also be passive or transient, without significant amplification of bacterial numbers while in the animal host. Animals may be classified as reservoir species, spillover hosts, or dead-end hosts. This classification is based on the animal's ability to (i) transmit STEC to other animal species and (ii) maintain STEC infection in the absence of continuous exposure. Animal reservoirs are able to maintain STEC infections in the absence of continuous STEC exposure and transmit infection to other species. Spillover hosts, although capable of transmitting STEC to other animals, are unable to maintain infection in the absence of repeated exposure. The large diversity of reservoir and spillover host species and the survival of the organism in environmental niches result in complex pathways of transmission that are difficult to interrupt.
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24
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Birth of a Pathogen. Food Saf (Tokyo) 2014. [DOI: 10.1128/9781555816186.ch6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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25
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Araújo S, Henriques IS, Leandro SM, Alves A, Pereira A, Correia A. Gulls identified as major source of fecal pollution in coastal waters: a microbial source tracking study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 470-471:84-91. [PMID: 24140684 DOI: 10.1016/j.scitotenv.2013.09.075] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 09/11/2013] [Accepted: 09/24/2013] [Indexed: 06/02/2023]
Abstract
Gulls were reported as sources of fecal pollution in coastal environments and potential vectors of human infections. Microbial source tracking (MST) methods were rarely tested to identify this pollution origin. This study was conducted to ascertain the source of water fecal contamination in the Berlenga Island, Portugal. A total of 169 Escherichia coli isolates from human sewage, 423 isolates from gull feces and 334 water isolates were analyzed by BOX-PCR. An average correct classification of 79.3% was achieved. When an 85% similarity cutoff was applied 24% of water isolates were present in gull feces against 2.7% detected in sewage. Jackknifing resulted in 29.3% of water isolates classified as gull, and 10.8% classified as human. Results indicate that gulls constitute a major source of water contamination in the Berlenga Island. This study validated a methodology to differentiate human and gull fecal pollution sources in a real case of a contaminated beach.
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Affiliation(s)
- Susana Araújo
- Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - Isabel S Henriques
- Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
| | - Sérgio Miguel Leandro
- GIRM, Marine Resources Research Group, School of Tourism and Maritime Technology, Polytechnic Institute of Leiria, Campus 4, 2520-641 Peniche, Portugal
| | - Artur Alves
- Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - Anabela Pereira
- Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - António Correia
- Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
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Abstract
ABSTRACT
As the manufacture of cheese relies in part on the select outgrowth of microorganisms, such conditions can also allow for the multiplication of unwanted contaminants. Milk ultimately becomes contaminated with microorganisms originating from infection, the farm environment, and feedstuffs, as well as milking and processing equipment. Thus, poor sanitation, improper milk handling, and animal health issues can result in not only decreased yield and poor quality but also sporadic cases and outbreaks of dairy-related disease. The entry, establishment, and persistence of food-borne pathogens in dairy processing environments also present a considerable risk to products postprocessing. Food safety management systems coupled with regulatory policies and microbiological standards for milk and milk products currently implemented in various nations work to reduce risk while improving the quality and safety of cheese and other dairy products. With that, cheese has enjoyed an excellent food safety record with relatively few outbreaks of food-borne disease considering the amount of cheese produced and consumed worldwide. However, as cheese production and consumption continue to grow, we must remain vigilant in ensuring the continued production of safe, high-quality cheese.
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Occurrence of diarrheagenic virulence genes and genetic diversity in Escherichia coli isolates from fecal material of various avian hosts in British Columbia, Canada. Appl Environ Microbiol 2014; 80:1933-40. [PMID: 24441159 DOI: 10.1128/aem.03949-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Contamination of surface water by fecal microorganisms originating from human and nonhuman sources is a public health concern. In the present study, Escherichia coli isolates (n = 412) from the feces of various avian host sources were screened for various virulence genes: stx1 and stx2 (Shiga toxin-producing E. coli [STEC]), eae (enteropathogenic E. coli [EPEC]), est-h, est-p, and elt (encoding heat-stable toxin [ST] variants STh and STp and heat-labile toxin [LT], respectively) (enterotoxigenic E. coli [ETEC]), and ipaH (enteroinvasive E. coli [EIEC]). None of the isolates were found to be positive for stx1, while 23% (n = 93) were positive for only stx2, representing STEC, and 15% (n = 63) were positive for only eae, representing EPEC. In addition, five strains obtained from pheasant were positive for both stx2 and eae and were confirmed as non-O157 by using an E. coli O157 rfb (rfbO157) TaqMan assay. Isolates positive for the virulence genes associated with ETEC and EIEC were not detected in any of the hosts. The repetitive element palindromic PCR (rep-PCR) fingerprint analysis identified 143 unique fingerprints, with an overall Shannon diversity index of 2.36. Multivariate analysis of variance (MANOVA) showed that the majority of the STEC and EPEC isolates were genotypically distinct from nonpathogenic E. coli and clustered independently. MANOVA analysis also revealed spatial variation among the E. coli isolates, since the majority of the isolates clustered according to the sampling locations. Although the presence of virulence genes alone cannot be used to determine the pathogenicity of strains, results from this study show that potentially pathogenic STEC and EPEC strains can be found in some of the avian hosts studied and may contaminate surface water and potentially impact human health.
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Nyberg KA, Vinnerås B, Albihn A. Managing Salmonella Typhimurium and Escherichia coli O157:H7 in soil with hydrated lime - An outdoor study in lysimeters and field plots. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2014; 49:45-50. [PMID: 24138468 DOI: 10.1080/03601234.2013.836901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
An outbreak of Salmonella Typhimurium or E. coli O157:H7 among domestic animals can have great financial consequences for an animal enterprise but also be a threat for public health as there is a risk for transmission of the infection through the environment. In order to minimize disease transmission, it is important to treat not only the affected animals but also the areas on which they have been kept. In the present study, the effect of hydrated lime as a treatment for Salmonella Typhimurium or E. coli O157:H7 contaminated soil was investigated. The study was performed outdoors, in a lysimeter system and in field plots. The soils were spiked with Salmonella Typhimurium and/or E. coli O157:H7 and hydrated lime was added at three different concentrations (0.5, 1 and 2%). Sampling was performed over one month, and the levels of bacteria were analyzed by standard culture methods. In addition, the soil pH was monitored throughout the study. The results showed that application of 0.5-1 kg hydrated lime per m(2) reduced both Salmonella Typhimurium and E. coli O157:H7 numbers to below the detection limit (2 log10 CFU g-1 soil) in 3-7 days. Lower application rates of hydrated lime did not reduce pathogen numbers in the lysimeter study, but in the field plots no E. coli O157:H7 was detected at the end of the four-week study period regardless of hydrated lime application. A recommended strategy for treating a Salmonella Typhimurium or E. coli O157:H7 contaminated soil could therefore be to monitor the pH over the time of treatment and to repeat hydrated lime application if a decrease in pH is observed.
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Affiliation(s)
- Karin A Nyberg
- a Department of Chemistry, Environment and Feed Hygiene , National Veterinary Institute , Uppsala , Sweden
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Isolation of Escherichia coli 0157:H7 strain from fecal samples of zoo animal. ScientificWorldJournal 2013; 2013:843968. [PMID: 24489514 PMCID: PMC3893011 DOI: 10.1155/2013/843968] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 09/29/2013] [Indexed: 11/21/2022] Open
Abstract
The isolation and characterization of Escherichia coli O157:H7 strains from 22 out of 174 fecal samples from petting zoo animals representing twenty-two different species (camel, lion, goats, zebra, bear, baboon monkey, Siberian monkey, deer, elk, llama, pony, horses, fox, kangaroo, wolf, porcupine, chickens, tiger, ostrich, hyena, dogs, and wildcats) were investigated. One petting Al-Zawraa zoological society of Baghdad was investigated for E. coli O157:H7 over a 16-month period that spanned two summer and two autumn seasons. Variation in the occurrence of E. coli O157:H7-positive petting zoo animals was observed, with animals being culture positive only in the summer months but not in the spring, autumn, or winter. E. coli O157:H7 isolates were distinguished by agglutination with E. coli O157:H7 latex reagent (Oxoid), identified among the isolates, which showed that multiple E. coli strains were isolated from one petting zoo animal, in which a single animal simultaneously shed multiple E. coli strains; E. coli O157:H7 was isolated only by selective enrichment culture of 2 g of petting zoo animal feces. In contrast, strains other than O157:H7 were cultured from feces of petting zoo animals without enrichment.
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Park S, Szonyi B, Gautam R, Nightingale K, Anciso J, Ivanek R. Risk factors for microbial contamination in fruits and vegetables at the preharvest level: a systematic review. J Food Prot 2012; 75:2055-81. [PMID: 23127717 DOI: 10.4315/0362-028x.jfp-12-160] [Citation(s) in RCA: 138] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The objective of this study was to perform a systematic review of risk factors for contamination of fruits and vegetables with Listeria monocytogenes, Salmonella, and Escherichia coli O157:H7 at the preharvest level. Relevant studies were identified by searching six electronic databases: MEDLINE, EMBASE, CAB Abstracts, AGRIS, AGRICOLA, and FSTA, using the following thesaurus terms: L. monocytogenes, Salmonella, E. coli O157 AND fruit, vegetable. All search terms were exploded to find all related subheadings. To be eligible, studies had to be prospective controlled trials or observational studies at the preharvest level and had to show clear and sufficient information on the process in which the produce was contaminated. Of the 3,463 citations identified, 68 studies fulfilled the eligibility criteria. Most of these studies were on leafy greens and tomatoes. Six studies assessed produce contamination with respect to animal host-related risk factors, and 20 studies assessed contamination with respect to pathogen characteristics. Sixty-two studies assessed the association between produce contamination and factors related to produce, water, and soil, as well as local ecological conditions of the production location. While evaluations of many risk factors for preharvest-level produce contamination have been reported, the quality assessment of the reviewed studies confirmed the existence of solid evidence for only some of them, including growing produce on clay-type soil, the application of contaminated or non-pH-stabilized manure, and the use of spray irrigation with contaminated water, with a particular risk of contamination on the lower leaf surface. In conclusion, synthesis of the reviewed studies suggests that reducing microbial contamination of irrigation water and soil are the most effective targets for the prevention and control of produce contamination. Furthermore, this review provides an inventory of the evaluated risk factors, including those requiring more research.
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Affiliation(s)
- Sangshin Park
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843, USA.
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Converse RR, Kinzelman JL, Sams EA, Hudgens E, Dufour AP, Ryu H, Santo-Domingo JW, Kelty CA, Shanks OC, Siefring SD, Haugland RA, Wade TJ. Dramatic improvements in beach water quality following gull removal. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:10206-13. [PMID: 22913457 DOI: 10.1021/es302306b] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Gulls are often cited as important contributors of fecal contamination to surface waters, and some recreational beaches have used gull control measures to improve microbial water quality. In this study, gulls were chased from a Lake Michigan beach using specially trained dogs, and water quality improvements were quantified. Fecal indicator bacteria and potentially pathogenic bacteria were measured before and during gull control using culture methods and quantitative polymerase chain reaction (qPCR). Harassment by dogs was an effective method of gull control: average daily gull populations fell from 665 before to 17 during intervention; and a significant reduction in the density of a gull-associated marker was observed (p < 0.001). Enterococcus spp. and Escherichia coli densities were also significantly reduced during gull control (p < 0.001 and p = 0.012, respectively for culture methods; p = 0.012 and p = 0.034, respectively for qPCR). Linear regression results indicate that a 50% reduction in gulls was associated with a 38% and 29% decrease in Enterococcus spp. and E. coli densities, respectively. Potentially human pathogenic bacteria were detected on 64% of days prior to gull control and absent during gull intervention, a significant reduction (p = 0.005). This study demonstrates that gull removal can be a highly successful beach remedial action to improve microbial water quality.
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Affiliation(s)
- Reagan R Converse
- US Environmental Protection Agency, Chapel Hill, North Carolina 27514, United States.
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Pointon A, Kiermeier A, Fegan N. Review of the impact of pre-slaughter feed curfews of cattle, sheep and goats on food safety and carcase hygiene in Australia. Food Control 2012. [DOI: 10.1016/j.foodcont.2012.01.034] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Escherichia coli O157:H7 in beef cattle: on farm contamination and pre-slaughter control methods. Anim Health Res Rev 2012; 12:197-211. [PMID: 22152293 DOI: 10.1017/s1466252311000132] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
This paper addresses food safety in beef cattle production, with particular emphasis on factors that affect the prevalence of Escherichia coli O157:H7 in beef cattle and on control methods that have been investigated. Product recalls and foodborne diseases due to this organism continue to occur even though control measures have been under investigation for over 20 years. Most meatborne outbreaks are due to improper food handling practices and consumption of undercooked meat. However, the majority of pathogenic bacteria that can spread at slaughter by cross-contamination can be traced back to the farm rather than originating from the slaughter plant. This would ideally require the adoption of rigorous on-farm intervention strategies to mitigate risks at the farm level. On-farm strategies to control and reduce E. coli O157:H7 at the farm level will reduce the risk of carcass contamination at slaughter and processing facilities although they will not eliminate E. coli O157:H7. The most successful strategy for reducing the risk of contamination of beef and beef products will involve the implementation of both pre- and post-harvest measures.
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Foti M, Rinaldo D, Guercio A, Giacopello C, Aleo A, De Leo F, Fisichella V, Mammina C. Pathogenic microorganisms carried by migratory birds passing through the territory of the island of Ustica, Sicily (Italy). Avian Pathol 2011; 40:405-9. [PMID: 21812720 DOI: 10.1080/03079457.2011.588940] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Several studies have shown that migratory birds play an important role in the ecology, circulation and dissemination of pathogenic organisms. In October 2006, a health status evaluation was performed on a large population of migratory birds passing through the territory of Ustica (Italy), an island located on the migration route of many species of birds to Africa, and various laboratory tests were conducted. In total, 218 faecal swabs and the internal organs of 21 subjects found dead in nets were collected for bacteriological and virological examination, including avian influenza and Newcastle disease. In addition, 19 pooled fresh faecal samples were collected for mycological examination. The bacteriological analysis produced 183 strains belonging to 28 different species of the Enterobacteriaceae family. In particular, Salmonella bongori, Yersinia enterocolitica and Klebsiella pneumonia strains were isolated. Almost all of the isolates were susceptible to sulphamethoxazole/trimethoprime (99.4%), cefotaxime (98.9%), nalidixic acid (96.7%), chloramphenicol (95.6%), and tetracycline (93.4%). Alternatively, many strains were resistant to ampicillin (42.6%), amoxicillin-clavulanic acid (42.6%), and streptomycin (43.7%). According to reverse transcriptase-polymerase chain reaction analysis, all of the samples were negative for the M gene of avian influenza virus. Moreover, isolation tests conducted on specific pathogen free eggs were negative for avian influenza and Newcastle disease. Several hyphomycetes and yeasts belonging to different genera were present in the specimens, and Cryptococcus neoformans was observed in a pooled faecal sample. Antibiotic resistance in wildlife can be monitored to evaluate the impact of anthropic pressure. Furthermore, migratory birds are potential reservoirs of pathogenic agents; thus, they can be regarded as sentinel species and used as environmental health indicators.
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Affiliation(s)
- Maria Foti
- Department of Veterinary Public Health, University of Messina, Polo Universitario dell'Annunziata, 98168, Messina, Italy.
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Martiny AC, Martiny JBH, Weihe C, Field A, Ellis JC. Functional metagenomics reveals previously unrecognized diversity of antibiotic resistance genes in gulls. Front Microbiol 2011; 2:238. [PMID: 22347872 PMCID: PMC3275322 DOI: 10.3389/fmicb.2011.00238] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 11/11/2011] [Indexed: 11/17/2022] Open
Abstract
Wildlife may facilitate the spread of antibiotic resistance (AR) between human-dominated habitats and the surrounding environment. Here, we use functional metagenomics to survey the diversity and genomic context of AR genes in gulls. Using this approach, we found a variety of AR genes not previously detected in gulls and wildlife, including class A and C β-lactamases as well as six tetracycline resistance gene types. An analysis of the flanking sequences indicates that most of these genes are present in Enterobacteriaceae and various Gram-positive bacteria. In addition to finding known gene types, we detected 31 previously undescribed AR genes. These undescribed genes include one most similar to an uncharacterized gene in Verrucomicrobium and another to a putative DNA repair protein in Lactobacillus. Overall, the study more than doubled the number of clinically relevant AR gene types known to be carried by gulls or by wildlife in general. Together with the propensity of gulls to visit human-dominated habitats, this high diversity of AR gene types suggests that gulls could facilitate the spread of AR.
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Affiliation(s)
- Adam C Martiny
- Department of Earth System Science, University of California Irvine, CA, USA
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Rosales-Castillo JA, Vázquez-Garcidueñas MS, Álvarez-Hernández H, Chassin-Noria O, Varela-Murillo AI, Zavala-Páramo MG, Cano-Camacho H, Vázquez-Marrufo G. Genetic diversity and population structure of Escherichia coli from neighboring small-scale dairy farms. J Microbiol 2011; 49:693-702. [DOI: 10.1007/s12275-011-0461-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 04/21/2011] [Indexed: 10/15/2022]
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Williams M, Pearl D, LeJeune J. Multiple-locus variable-nucleotide tandem repeat subtype analysis implicates European starlings as biological vectors for Escherichia coli O157:H7 in Ohio, USA. J Appl Microbiol 2011; 111:982-8. [DOI: 10.1111/j.1365-2672.2011.05102.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ma J, Ibekwe AM, Yi X, Wang H, Yamazaki A, Crowley DE, Yang CH. Persistence of Escherichia coli O157:H7 and its mutants in soils. PLoS One 2011; 6:e23191. [PMID: 21826238 PMCID: PMC3149627 DOI: 10.1371/journal.pone.0023191] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Accepted: 07/08/2011] [Indexed: 11/18/2022] Open
Abstract
The persistence of Shiga toxin-producing E. coli O157:H7 in the environment poses a serious threat to public health. However, the role of Shiga toxins and other virulence factors in the survival of E. coli O157:H7 is poorly defined. The aim of this study was to determine if the virulence factors, stx₁, stx₂, stx₁₋₂, and eae in E. coli O157:H7 EDL933 play any significant role in the growth of this pathogen in rich media and in soils. Isogenic deletion mutants that were missing one of four virulence factors, stx₁, stx₂, stx₁₋₂, and eae in E. coli O157:H7 EDL933 were constructed, and their growth in rich media and survival in soils with distinct texture and chemistry were characterized. The survival data were successfully analyzed using Double Weibull model, and the modeling parameters of the mutant strains were not significantly different from those of the wild type. The calculated T(d) (time needed to reach the detection limit, 100 CFU/g soil) for loamy sand, sandy loam, and silty clay was 32, 80, and 110 days, respectively. It was also found that T(d) was positively correlated with soil structure (e.g. clay content), and soil chemistry (e.g. total nitrogen, total carbon, and water extractable organic carbon). The results of this study showed that the possession of Shiga toxins and intimin in E. coli O157:H7 might not play any important role in its survival in soils. The double deletion mutant of E. coli O157:H7 (stx₁⁻stx₂⁻) may be a good substitute to use for the investigation of transport, fate, and survival of E. coli O157:H7 in the environment where the use of pathogenic strains are prohibited by law since the mutants showed the same characteristics in both culture media and environmental samples.
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Affiliation(s)
- Jincai Ma
- United States Salinity Laboratory, Agriculture Research Service, United States Department of Agriculture, Riverside, California, United States of America
- Department of Environmental Sciences, University of California Riverside, Riverside, California, United States of America
| | - A. Mark Ibekwe
- United States Salinity Laboratory, Agriculture Research Service, United States Department of Agriculture, Riverside, California, United States of America
| | - Xuan Yi
- Department of Biological Sciences, University of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Haizhen Wang
- United States Salinity Laboratory, Agriculture Research Service, United States Department of Agriculture, Riverside, California, United States of America
- Department of Environmental Sciences, University of California Riverside, Riverside, California, United States of America
- Institute of Soil and Water Resources and Environmental Science, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, Zhejiang University, Hangzhou, China
| | - Akihiro Yamazaki
- Department of Biological Sciences, University of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - David E. Crowley
- Department of Environmental Sciences, University of California Riverside, Riverside, California, United States of America
| | - Ching-Hong Yang
- Department of Biological Sciences, University of Wisconsin, Milwaukee, Wisconsin, United States of America
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Outbreak of Escherichia coli 0157:H7 related to animal contact at a petting zoo. Can J Infect Dis 2011; 13:175-81. [PMID: 18159389 DOI: 10.1155/2002/873832] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2000] [Accepted: 07/30/2001] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE To determine the cause of an outbreak of Escherichia coli 0157:H7 related to animal exposures so that further transmission could be prevented. DESIGN Description of laboratory investigations and a case control study. SETTING Agricultural pavilion at an annual fair in Ontario. POPULATION People with laboratory evidence of E coli 0157:H7 (seven people) and others with diarrhea (155 people) who called the health unit following a media release were interviewed. Animals that were accessed most frequently by the public in the agriculture pavilion were tested for E coli 0157:H7. In the case control study, a case was defined as someone with laboratory confirmed E coli 0157:H7, or someone who developed severe or bloody diarrhea two to eight days after attending the agricultural pavilion at the fair (61 people). A convenience sample of people who attended the agricultural pavilion but did not develop diarrhea was selected as the control group (89 people). INTERVENTIONS Human and animal E coli 0157:H7 specimens were subtyped. Cases and controls were interviewed using a standardized questionnaire. RESULTS Subtyping of the seven human isolates of E coli 0157:H7 revealed five that were of an extremely uncommon phage type. Three samples from goats and one from sheep at the petting zoo in the agricultural pavilion were of this same phage type. The case control study also implicated goats (odds ratio [OR] 3.65; 95% CI 1.63 to 8.52) and sheep (OR 2.94; 95% CI 1.33 to 6.57) from the petting zoo. CONCLUSIONS Results of this investigation suggest strongly that the goats and sheep from the petting zoo were the source of this outbreak of E coli 0157:H7.
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Peng S, Tasara T, Hummerjohann J, Stephan R. An overview of molecular stress response mechanisms in Escherichia coli contributing to survival of Shiga toxin-producing Escherichia coli during raw milk cheese production. J Food Prot 2011; 74:849-64. [PMID: 21549061 DOI: 10.4315/0362-028x.jfp-10-469] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The ability of foodborne pathogens to survive in certain foods mainly depends on stress response mechanisms. Insight into molecular properties enabling pathogenic bacteria to survive in food is valuable for improvement of the control of pathogens during food processing. Raw milk cheeses are a potential source for human infections with Shiga toxin-producing Escherichia coli (STEC). In this review, we focused on the stress response mechanisms important for allowing STEC to survive raw milk cheese production processes. The major components and regulation pathways for general, acid, osmotic, and heat shock stress responses in E. coli and the implications of these responses for the survival of STEC in raw milk cheeses are discussed.
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Affiliation(s)
- Silvio Peng
- Institute for Food Safety and Hygiene, University of Zurich, Winterthurerstrasse 272, 8057 Zürich, Switzerland
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Cobbaut K, Houf K, Boyen F, Haesebrouck F, De Zutter L. Genotyping and antimicrobial resistance patterns of Escherichia coli O157 originating from cattle farms. Foodborne Pathog Dis 2011; 8:719-24. [PMID: 21381926 DOI: 10.1089/fpd.2010.0767] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
During a Escherichia coli O157 prevalence study on cattle farms, 324 E. coli O157 isolates were collected from 68 out of 180 cattle farms. All isolates harbored the eaeA gene and the enterohemolysin (ehxA) gene. The majority of the strains only contained vtx2 (245 isolates), the combination of vtx1 and vtx2 was detected in 50 isolates, and in 29 isolates none of the vtx genes was present. Pulsed-field gel electrophoresis (PFGE) revealed that at a similarity level of 98% the isolates grouped into 83 different genotypes, 76 of which were only detected on one farm. Twenty-two out of the 68 positive farms harbored isolates belonging to more than one PFGE type, with a maximum of four different PFGE types. Minimal inhibitory concentrations of 10 antimicrobial agents were determined on a subset of 116 isolates, that is, one isolate per positive age category per farm. Acquired resistance to at least one antimicrobial agent was detected in 18 isolates and within a farm, only one resistance pattern was observed. All these 18 isolates were resistant toward streptomycin, and 16 of them also showed resistance toward sulfisoxazole. Six isolates were resistant to three or more antimicrobial agents.
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Affiliation(s)
- Katrijn Cobbaut
- Department of Veterinary Public Health and Food Safety, Ghent University, Merelbeke, Belgium
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Money P, Kelly AF, Gould SWJ, Denholm-Price J, Threlfall EJ, Fielder MD. Cattle, weather and water: mapping Escherichia coli O157:H7 infections in humans in England and Scotland. Environ Microbiol 2011; 12:2633-44. [PMID: 20642796 DOI: 10.1111/j.1462-2920.2010.02293.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Entero-haemorrhagic Escherichia coli O157:H7 is a zoonotic pathogen, responsible for a relatively small number of food poisoning and illness outbreaks each year, when compared with other food-borne bacteria capable of causing infections in the population. Nevertheless, E. coli O157:H7 is a bacterial pathogen associated with severe human illnesses including bloody diarrhoea and haemolytic uremic syndrome occurring in both outbreak and sporadic settings. In England and Wales approximately 1% of all laboratory-confirmed cases of food poisoning are the result of E. coli O157:H7; however, in Scotland this figure increases to 3%. When the size of the population is taken into account and the rate of E. coli O157:H7 confirmed cases per 100,000 population is examined, the rate of E. coli 0157:H7 infections in Scotland is much greater than England and Wales. The routes of transmission have changed over time, with new routes of transmission such as farm visits emerging. The prevalence of E. coli O157:H7 has a seasonal dependency, with greater faecal shedding of the organism in the warmer months; this is directly mirrored in the increased reporting of E. coli O157:H7 infection among hospitalized patients. This review attempts to suggest why this phenomenon occurs, paying particular attention to weather, animal movement and private water supplies.
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Affiliation(s)
- P Money
- School of Life Sciences, Kingston University, Penrhyn Road, Kingston Upon Thames, London KT1 2EE, UK
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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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Antibiotic-resistant Escherichia coli bacteria, including strains with genes encoding the extended-spectrum beta-lactamase and QnrS, in waterbirds on the Baltic Sea Coast of Poland. Appl Environ Microbiol 2010; 76:8126-34. [PMID: 20952638 DOI: 10.1128/aem.01446-10] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Individual cloacal swabs of mallards (Anas platyrhynchos) and of herring gulls (Larus argentatus), as well as samples of waterbird feces obtained in 2008 and 2009, were cultivated for Escherichia coli. Isolates of E. coli were tested for susceptibilities to 12 antimicrobial agents by the disk diffusion method. Moreover, the samples were subcultivated on MacConkey agar (MCA) containing cefotaxime (2 mg liter(-1)) to detect E. coli with extended-spectrum beta-lactamase (ESBL) and subsequently on MCA supplemented with ciprofloxacin (0.05 mg liter(-1)) and MCA with nalidixic acid (20 mg liter(-1)) to isolate fluoroquinolone-resistant E. coli. PCR was used to detect specific antibiotic resistance genes. We found 9 E. coli isolates producing ESBL with bla genes: bla(CTX-M-1) (6 isolates), bla(CTX-M-9) plus bla(TEM-1b) (1 isolate), bla(CTX-M-15) plus bla(OXA-1) (1 isolate), and bla(SHV-12) (1 isolate). In the isolate with bla(CTX-M-15), the gene aac(6)-Ib-cr was also detected. The bla genes were harbored by transferable plasmids of the IncN and IncI1 groups. Nine quinolone-resistant E. coli isolates with qnrS genes were found and characterized. The gene qnrS was associated with a Tn3-like transposon on the IncX1 plasmid together with bla(TEM-1) in two isolates. The gene qnrS was also harbored by conjugative plasmids of the IncN and IncX2 groups. Even if populations of wild birds are not directly influenced by antibiotic practice, we have demonstrated that antibiotic-resistant E. coli strains, including strains with various ESBL and qnrS genes, are found in the feces of wild birds on the coast of the Baltic Sea in Poland.
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Berry ED, Wells JE. Escherichia coli O157:H7: recent advances in research on occurrence, transmission, and control in cattle and the production environment. ADVANCES IN FOOD AND NUTRITION RESEARCH 2010; 60:67-117. [PMID: 20691954 DOI: 10.1016/s1043-4526(10)60004-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Escherichia coli O157:H7 is a zoonotic pathogen that is an important cause of human foodborne and waterborne disease, with a spectrum of illnesses ranging from asymptomatic carriage and diarrhea to the sometimes fatal hemolytic uremic syndrome. Outbreaks of E. coli O157:H7 disease are often associated with undercooked beef, but there are other sources of transmission, including water, produce, and animal contact, which can often be linked directly or indirectly to cattle. Thus, preharvest control of this pathogen in cattle production should have a large impact on reducing the risk of human foodborne illness. In this review, we will summarize preharvest research on E. coli O157:H7 in cattle and the production environment, focusing on factors that may influence the transmission, prevalence, and levels of this pathogen, such as season, diet, high-level shedders, and animal stress. In addition, we will discuss recent research on the reduction of this pathogen in cattle production, including vaccination, probiotics, bacteriophage, and manure treatments.
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Affiliation(s)
- Elaine D Berry
- U.S. Department of Agriculture, Agricultural Research Service, U.S. Meat Animal Research Center, Clay Center, Nebraska, USA.
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Ewers C, Guenther S, Wieler LH, Schierack P. Mallard ducks - a waterfowl species with high risk of distributing Escherichia coli pathogenic for humans. ENVIRONMENTAL MICROBIOLOGY REPORTS 2009; 1:510-7. [PMID: 23765929 DOI: 10.1111/j.1758-2229.2009.00058.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Mallard ducks may pose a so far underestimated risk to human and animal health by transmitting pathogenic Escherichia coli via their faecal deposits to various environmental sources. We processed Mallard duck faecal samples for E. coli and unique clones, as defined by pulsed-field gel electrophoresis (PFGE), were subsequently investigated for their virulence genotype and phylogenetic background. Multilocus sequence typing and in vivo experiments were performed for selected clones. Of 60 clones identified among 142 E. coli isolated from 175 samples, 15 (25%) were recovered from multiple individuals (up to 23 per clone). None of the clones harboured stx1 and stx2 genes and other intestinal pathogenic E. coli virulence-associated genes were only occasionally identified in the collection. In contrast, the clones possessed considerable numbers of VAGs (up to 30) linked with extraintestinal pathogenic E. coli (ExPEC). Their pathogenic potential was confirmed in chicken infection experiments. Moreover, selected clones were assigned to sequence types (STs) being most prominent for human ExPEC strains, including ST95 and ST73. One clone exhibited a multi-resistant phenotype against several antibiotics including beta-lactams, tetracyclines and sulfonamides. Mallard ducks have therefore to be considered as an important reservoir for zoonotic E. coli strains, thus serving as a substantial non-point source especially of strains capable of causing extraintestinal diseases.
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Affiliation(s)
- Christa Ewers
- Institut für Mikrobiologie und Tierseuchen, Fachbereich für Veterinärmedizin, Freie Universität Berlin, Germany. Fachbereich Bio-, Chemie- und Verfahrenstechnik, Fachhochschule Lausitz, Senftenberg, Germany
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Assessment of Shiga toxin-producing Escherichia coli isolates from wildlife meat as potential pathogens for humans. Appl Environ Microbiol 2009; 75:6462-70. [PMID: 19700552 DOI: 10.1128/aem.00904-09] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A total of 140 Shiga toxin-producing Escherichia coli (STEC) strains from wildlife meat (deer, wild boar, and hare) isolated in Germany between 1998 and 2006 were characterized with respect to their serotypes and virulence markers associated with human pathogenicity. The strains grouped into 38 serotypes, but eight O groups (21, 146, 128, 113, 22, 88, 6, and 91) and four H types (21, 28, 2, and 8) accounted for 71.4% and 75.7% of all STEC strains from game, respectively. Eighteen of the serotypes, including enterohemorrhagic E. coli (EHEC) O26:[H11] and O103:H2, were previously found to be associated with human illness. Genes linked to high-level virulence for humans (stx(2), stx(2d), and eae) were present in 46 (32.8%) STEC strains from game. Fifty-four STEC isolates from game belonged to serotypes which are frequently found in human patients (O103:H2, O26:H11, O113:H21, O91:H21, O128:H2, O146:H21, and O146:H28). These 54 STEC isolates were compared with 101 STEC isolates belonging to the same serotypes isolated from farm animals, from their food products, and from human patients. Within a given serotype, most STEC strains were similar with respect to their stx genotypes and other virulence attributes, regardless of origin. The 155 STEC strains were analyzed for genetic similarity by XbaI pulsed-field gel electrophoresis. O103:H2, O26:H11, O113:H21, O128:H2, and O146:H28 STEC isolates from game were 85 to 100% similar to STEC isolates of the same strains from human patients. By multilocus sequence typing, game EHEC O103:H2 strains were attributed to a clonal lineage associated with hemorrhagic diseases in humans. The results from our study indicate that game animals represent a reservoir for and a potential source of human pathogenic STEC and EHEC strains.
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Benskin CMH, Wilson K, Jones K, Hartley IR. Bacterial pathogens in wild birds: a review of the frequency and effects of infection. Biol Rev Camb Philos Soc 2009; 84:349-73. [DOI: 10.1111/j.1469-185x.2008.00076.x] [Citation(s) in RCA: 187] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Food safety aspects of dairy cow housing and husbandry systems. EFSA J 2009. [DOI: 10.2903/j.efsa.2009.1189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Pritchard GC, Smith R, Ellis-Iversen J, Cheasty T, Willshaw GA. Verocytotoxigenic Escherichia coli
O157 in animals on public amenity premises in England and Wales, 1997 to 2007. Vet Rec 2009; 164:545-9. [DOI: 10.1136/vr.164.18.545] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- G. C. Pritchard
- Veterinary Laboratories Agency (VLA) - Bury St Edmunds; Rougham Hill Bury St Edmunds Suffolk IP33 2RX
| | - R. Smith
- VLA - Weybridge; Woodham Lane, New Haw Addlestone Surrey KT15 3NB
| | - J. Ellis-Iversen
- VLA - Weybridge; Woodham Lane, New Haw Addlestone Surrey KT15 3NB
| | - T. Cheasty
- Laboratory of Enteric Pathogens; Centre for Infections; Health Protection Agency; 61 Colindale Avenue London NW9 5HT
| | - G. A. Willshaw
- Laboratory of Enteric Pathogens; Centre for Infections; Health Protection Agency; 61 Colindale Avenue London NW9 5HT
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