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Characteristics of Shiga Toxin-Producing Escherichia coli O157 in Slaughtered Reindeer from Northern Finland.

https://arctichealth.org/en/permalink/ahliterature283187
Source
J Food Prot. 2017 Mar;80(3):454-458
Publication Type
Article
Date
Mar-2017
Author
Claudio Zweifel
Lisa Fierz
Nicole Cernela
Sauli Laaksonen
Maria Fredriksson-Ahomaa
Roger Stephan
Source
J Food Prot. 2017 Mar;80(3):454-458
Date
Mar-2017
Language
English
Publication Type
Article
Keywords
Adhesins, Bacterial - genetics
Animals
Escherichia coli - genetics
Escherichia coli Infections - veterinary
Escherichia coli O157 - genetics
Escherichia coli Proteins - genetics
Feces
Finland
Humans
Reindeer - microbiology
Shiga-Toxigenic Escherichia coli - classification
Abstract
Fecal samples collected from 470 slaughtered reindeer 6 to 7 months of age were screened by real-time PCR (after enrichment) for Shiga toxin genes (stx) and then for Escherichia coli serogroup O157. Shiga toxin genes were found frequently (>30% of samples), and serogroup O157 was detected in 20% of the stx-positive samples. From these samples, a total of 25 E. coli O157:H(-) isolates (nonmotile but PCR positive for fliCH7) were obtained. Twenty-four of these E. coli O157:H(-) isolates did not ferment sorbitol and originated from one geographic area. These 24 isolates belonged to the multilocus sequence type 11, typical for Shiga toxin-producing E. coli (STEC) O157:H7 and O157:H(-), and harbored genes stx1a, stx2c, eae, and hlyA; the stx2c subtype has been associated with high virulence. In contrast, one E. coli O157:H(-) isolate (multilocus sequence type 11) did ferment sorbitol, lacked Shiga toxin genes, but was positive for eae, hlyA, and sfpA. This isolate closely resembled an STEC that has lost its Shiga toxin genes. Additional examination revealed that reindeer can be colonized by various other STEC isolates; 21 non-O157 STEC isolates belonged to four multilocus sequence types, harbored stx1a (8 isolates) or stx2b (13 isolates), and in the stx2b-positive isolates the recently described new allelic variants (subAB2-2 and subAB2-3) for subtilase cytotoxin were identified. Hence, slaughtered semidomesticated Finnish reindeer might constitute a little known reservoir for STEC O157:H7/H(-) and other serogroups, and the risk of direct or indirect transmission of these pathogens from reindeer to humans and domestic livestock must not be overlooked.
PubMed ID
28207302 View in PubMed
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Cold growth behaviour and genetic comparison of Canadian and Swiss Listeria monocytogenes strains associated with the food supply chain and human listeriosis cases.

https://arctichealth.org/en/permalink/ahliterature256814
Source
Food Microbiol. 2014 Jun;40:81-7
Publication Type
Article
Date
Jun-2014
Author
Carolina Arguedas-Villa
Jovana Kovacevic
Kevin J Allen
Roger Stephan
Taurai Tasara
Author Affiliation
Institute for Food Safety and Hygiene, Vetsuisse Faculty University of Zurich, Switzerland.
Source
Food Microbiol. 2014 Jun;40:81-7
Date
Jun-2014
Language
English
Publication Type
Article
Keywords
Adaptation, Physiological
Bacterial Proteins - genetics
Canada
Food chain
Food Microbiology
Food Supply
Humans
Listeria monocytogenes - classification - genetics - growth & development - isolation & purification
Listeriosis - microbiology
Phylogeny
Switzerland
Temperature
Abstract
Sixty-two strains of Listeria monocytogenes isolated in Canada and Switzerland were investigated. Comparison based on molecular genotypes confirmed that strains in these two countries are genetically diverse. Interestingly strains from both countries displayed similar range of cold growth phenotypic profiles. Based on cold growth lag phase duration periods displayed in BHI at 4??C, the strains were similarly divided into groups of fast, intermediate and slow cold adaptors. Overall Swiss strains had faster exponential cold growth rates compared to Canadian strains. However gene expression analysis revealed no significant differences between fast and slow cold adapting strains in the ability to induce nine cold adaptation genes (lmo0501, cspA, cspD, gbuA, lmo0688, pgpH, sigB, sigH and sigL) in response to cold stress exposure. Neither was the presence of Stress survival islet 1 (SSI-1) analysed by PCR associated with enhanced cold adaptation. Phylogeny based on the sigL gene subdivided strains from these two countries into two major and one minor cluster. Fast cold adaptors were more frequently in one of the major clusters (cluster A), whereas slow cold adaptors were mainly in the other (cluster B). Genetic differences between these two major clusters are associated with various amino acid substitutions in the predicted SigL proteins. Compared to the EGDe type strain and most slow cold adaptors, most fast cold adaptors exhibited five identical amino acid substitutions (M90L, S203A/S203T, S304N, S315N, and I383T) in their SigL proteins. We hypothesize that these amino acid changes might be associated with SigL protein structural and functional changes that may promote differences in cold growth behaviour between L.?monocytogenes strains.
PubMed ID
24549201 View in PubMed
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Presence of foodborne pathogens, extended-spectrum Ã?-lactamase -producing Enterobacteriaceae, and methicillin-resistant Staphylococcus aureus in slaughtered reindeer in northern Finland and Norway.

https://arctichealth.org/en/permalink/ahliterature279574
Source
Acta Vet Scand. 2017 Jan 03;59(1):2
Publication Type
Article
Date
Jan-03-2017
Author
Sauli Laaksonen
Antti Oksanen
Jérôme Julmi
Claudio Zweifel
Maria Fredriksson-Ahomaa
Roger Stephan
Source
Acta Vet Scand. 2017 Jan 03;59(1):2
Date
Jan-03-2017
Language
English
Publication Type
Article
Keywords
Animals
Enterobacteriaceae - drug effects - genetics - isolation & purification
Finland
Food Handling - standards
Food Microbiology
Meat - microbiology
Methicillin-Resistant Staphylococcus aureus
Norway
Reindeer
beta-Lactamases - metabolism
Abstract
Various food-producing animals were recognized in recent years as healthy carriers of bacterial pathogens causing human illness. In northern Fennoscandia, the husbandry of semi-domesticated reindeer (Rangifer tarandus tarandus) is a traditional livelihood and meat is the main product. This study determined the presence of selected foodborne pathogens, methicillin-resistant Staphylococcus aureus (MRSA), and extended-spectrum Ã?-lactamase (ESBL)-producing Enterobacteriaceae in healthy semi-domesticated reindeer at slaughter in northern Finland and Norway.
All 470 reindeer fecal samples tested negative for Salmonella spp., whereas L. monocytogenes was detected in 3%, Yersinia spp. in 10%, and Shiga toxins genes (stx1 and/or stx2) in 33% of the samples. Listeria monocytogenes isolates belonged to the serotype 1/2a (14/15) and 4b, Yersinia spp. were identified mainly as Y. kristensenii (30/46) and Y. enterocolitica (8/46), and stx2 predominated among the Shiga toxin genes (stx2 alone or in combination with stx1 was found in 25% of the samples). With regard to the frequency and distribution of stx1/stx2, striking differences were evident among the 10 different areas of origin. Hence, reindeer could constitute a reservoir for Shiga toxin-producing E. coli (STEC), but strain isolation and characterization is required for verification purposes and to assess the potential human pathogenicity of strains. On the other hand, the favorable antibiotic resistance profiles (only 5% of 95 E. coli isolates were resistant to one or more of the tested antibiotics) and the absence of MRSA and ESBL-producing Enterobacteriaceae (when applying selective methods) suggest only a limited risk of transmission to humans.
Healthy semi-domesticated reindeer in northern Finland and Norway can be carriers of certain bacterial foodborne pathogens. Strict compliance with good hygiene practices during any step of slaughter (in particular during dehiding and evisceration) is therefore of central importance to avoid carcass contamination and to prevent foodborne pathogens from entering the food chain.
PubMed ID
28049493 View in PubMed
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