DNA fingerprinting of Shiga-toxin producing Escherichia coli O157 based on Multiple-Locus Variable-Number Tandem-Repeats Analysis (MLVA)

BACKGROUND: The ability to react early to possible outbreaks of Escherichia coli O157:H7 and to trace possible sources relies on the availability of highly discriminatory and reliable techniques. The development of methods that are fast and has the potential for complete automation is needed for this important pathogen. METHODS: In all 73 isolates of shiga-toxin producing E. coli O157 (STEC) were used in this study. The two available fully sequenced STEC genomes were scanned for tandem repeated stretches of DNA, which were evaluated as polymorphic markers for isolate identification. RESULTS: The 73 E. coli isolates displayed 47 distinct patterns and the MLVA assay was capable of high discrimination between the E. coli O157 strains. The assay was fast and all the steps can be automated. CONCLUSION: The findings demonstrate a novel high discriminatory molecular typing method for the important pathogen E. coli O157 that is fast, robust and offers many advantages compared to current methods

Prevalence and characterization of integrons in blood culture Enterobacteriaceae and gastrointestinal Escherichia coli in Norway and reporting of a novel class 1 integron-located lincosamide resistance gene

BACKGROUND: Class 1 integrons contain genetic elements for site-specific recombination, capture and mobilization of resistance genes. Studies investigating the prevalence, distribution and types of integron located resistance genes are important for surveillance of antimicrobial resistance and to understand resistance development at the molecular level. METHODS: We determined the prevalence and genetic content of class 1 integrons in Enterobacteriaceae (strain collection 1, n = 192) and E. coli (strain collection 2, n = 53) from bloodstream infections in patients from six Norwegian hospitals by molecular techniques. Class 1 integrons were also characterized in 54 randomly selected multiresistant E. coli isolates from gastrointestinal human infections (strain collection 3). RESULTS: Class 1 integrons were present in 10.9% of the Enterobacteriaceae blood culture isolates of collection 1, all but one (S. Typhi) being E. coli. Data indicated variations in class 1 integron prevalence between hospitals. Class 1 integrons were present in 37% and 34% of the resistant blood culture isolates (collection 1 and 2, respectively) and in 42% of the resistant gastrointestinal E. coli. We detected a total of 10 distinct integron cassette PCR amplicons that varied in size between 0.15 kb and 2.2 kb and contained between zero and three resistance genes. Cassettes encoding resistance to trimethoprim and aminoglycosides were most common. We identified and characterized a novel plasmid-located integron with a cassette-bound novel gene (linF) located downstream of an aadA2 gene cassette. The linF gene encoded a putative 273 aa lincosamide nucleotidyltransferase resistance protein and conferred resistance to lincomycin and clindamycin. The deduced LinF amino acid sequence displayed approximately 35% identity to the Enterococcus faecium and Enterococcus faecalis nucleotidyl transferases encoded by linB and linB' CONCLUSIONS: The present study demonstrated an overall low and stable prevalence of class 1 integron gene cassettes in clinical Enterobacteriaceae and E. coli isolates in Norway. Characterization of the novel lincosamide resistance gene extends the growing list of class 1 integron gene cassettes that confer resistance to an increasing number of antibiotics

Risk factors for sporadic domestically acquired Campylobacter infections in Norway 2010–2011: A national prospective case-control study

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited: https://creativecommons.org/licenses/by/4.0/"Background: Campylobacteriosis is the most frequently reported food- and waterborne infection in Norway. We investigated the risk factors for sporadic Campylobacter infections in Norway in order to identify areas where control and prevention measures could be improved."Funds were provided for the preparation of data collection materials by the Norwegian Food Safety Authority and the Norwegian Veterinary Institut

A risk assessment of shiga toxin-producing Escherichia coli (STEC) in the Norwegian meat chain with emphasis on dry-cured sausages

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Outbreak of Yersinia enterocolitica Serogroup O:9 Infection and Processed Pork, Norway

An outbreak involving 11 persons infected with Yersinia enterocolitica O:9 was investigated in Norway in February 2006. A case-control study and microbiologic investigation indicated a ready-to-eat pork product as the probable source. Appropriate control measures are needed to address consumer risk associated with this product

Risk ranking and source attribution of food- and waterborne pathogens for surveillance purposes. Opinion of the Panel on Biological Hazards of the Norwegian Scientific Committee for Food and Environment

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Risk ranking and source attribution of food- and waterborne pathogens for surveillance purposes

publishedVersio

Risk ranking and source attribution of food- and waterborne pathogens for surveillance purposes

publishedVersio

Risk ranking and source attribution of food- and waterborne pathogens for surveillance purposes. Opinion of the Panel on Biological Hazards of the Norwegian Scientific Committee for Food and Environment

publishedVersio