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Objectives: The objective of this study was to determine the population structure of Escherichia coli ST73 isolated from human bacteraemia and urinary tract infections. Methods: The genomes of 22 E. coli ST73 isolates were sequenced using the Illumina HiSeq platform. Highresolution SNP typing was used to create a phylogenetic tree. Comparative genomics were also performed using a pangenome approach. In silico and S1-PFGE plasmid profiling was conducted, and isolates were checked for their ability to survive exposure to human serum. Results: E. coli ST73 isolates circulating in clinically unrelated episodes show a high degree of diversity at a whole-genome level, but exhibit conservation in gene content, particularly in virulence-associated gene carriage. The isolates also contain a highly diverse plasmid pool that confers MDR via carriage of CTX-M genes. Conclusions: Our data show that a rise in incidence of MDR E. coli ST73 clinical isolates is not due to a circulating outbreak strain as in E. coli ST131. Rather the ST73 circulating strains are distantly related and carry a diverse set of resistance plasmids. This suggests that the evolutionary events behind emergence of drug-resistant E. coli differ between lineages. [ABSTRACT FROM AUTHOR]

The SAS™ Molecular tests Escherichia coli O157 Detection method, a loop-mediated isothermal amplifcation method, performed as well as or better than the U.S. Department of Agriculture, Food Safety Inspection Service Microbiology Laboratory Guidebook and the U.S. Food and Drug Administration Bacteriological Analytical Manual reference methods for ground beef, beef trim, bagged mixed lettuce, and fresh spinach. Ground beef (30% fat, 25 g test portion) was validated for 7-8 h enrichment, leafy greens were validated in a 6-7 h enrichment, and ground beef (30% fat, 375 g composite test portion) and beef trim (375 g composite test portion) were validated in a 16-20 h enrichment. The method performance for meat and leafy green matrixes was also shown to be acceptable under conditions of co-enrichment with Salmonella. Thus, after a short co-enrichment step, ground beef, beef trim, lettuce, and spinach can be tested for both Salmonella and E. coli O157. The SAS Molecular tests Salmonella Detection Kit was validated using the same test portions as for the SAS Molecular tests E. coli O157 Detection Kit and those results are presented in a separate report. Inclusivity and exclusivity testing revealed no false negatives and no false positives among the 50 E. coli O157 strains, including H7 and non-motile strains, and 30 non-E. coli O157 strains examined. Finally, the method was shown to be robust when variations to DNA extract hold time and DNA volume were varied. The method comparison and robustness data suggest a full 7 h enrichment time should be used for 25 g ground beef test portions. [ABSTRACT FROM AUTHOR]

Commensal Escherichia coli isolates from healthy zoo animals kept in Ostrava Zoological Garden, Czech Republic, were investigated to evaluate the dissemination of extended-spectrum beta-lactamase ( ESBL) and plasmid-mediated quinolone resistance ( PMQR) genes. A total of 160 faecal samples of various animal species were inoculated onto Mac Conkey agar with cefotaxime (2 mg L−1) or ciprofloxacin (0.05 mg L−1) to obtain ESBL- or PMQR-positive E. coli isolates. Clonality of E. coli isolates was investigated by multilocus sequence typing and pulsed-field gel electrophoresis. Plasmids carrying ESBL or PMQR genes were typed by PCR-based replicon typing, plasmid multilocus sequence typing and restriction fragment length polymorphism. Forty-nine (71%, n = 69) cefotaxime-resistant and 15 (16%, n = 94) ciprofloxacin-resistant E. coli isolates harboured ESBL or PMQR genes. Isolates were assigned to 18 sequence types ( ST) and 20 clusters according to their macrorestriction patterns by pulsed-field gel electrophoresis. The genes bla CTX-M-1 and qnrS1 were detected on highly related IncI1 plasmids assigned to clonal complex 3 ( ST3, ST38) and on non-related IncN plasmids of ST1 and ST3, respectively. The gene qnrS1 was located on related IncX1 plasmids. Dissemination of antibiotic resistance is associated with spreading of particular E. coli clones and plasmids of specific incompatibility groups among various animal species. [ABSTRACT FROM AUTHOR]

In this study, the effects of thermosonication and thermal treatment on Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice were investigated at 50 and 60°C. Besides, nonlethal injury of Salm. Enteritidis after both treatments was also examined. The highest inactivation was attained with thermosonication at 60°C. The inactivation rate was different for both pathogens, and Salm. Enteritidis was found to be more sensitive to thermosonication than E. coli O157:H7. Salmonella Enteritidis was recovered in all treated samples, except those subjected to more than 5-min thermosonication at 60°C. It was found that the introduction of high-intensity ultrasound enhanced the inactivation of pathogens compared to thermal treatment alone. On the other hand, Salm. Enteritidis was detected in a number of samples following incubation in universal pre-enrichment broth, but no growth was detected after incubation in mango juice. Significance and Impact of the Study Fruit juices are commonly heat treated to inactivate micro-organisms and enzymes. However, excessive heat treatments may result in undesirable changes in juice quality. Treatment by power ultrasound, a nonthermal technology, may be an alternative processing technique to pasteurize fruit juices. This study highlights the effectiveness of thermosonication in inactivating Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice. [ABSTRACT FROM AUTHOR]

The article discusses the identification of OXA-48 producing escherichia coli isolates, that cause urinary tract infection, in patients of Christchurch, New Zealand. Topics include the transmission of escherichia coli disease, the isolate's antimicrobial susceptibility, the public health initiatives in New Zealand The use of epidemiological investigation, plasmid analysis, and bioinformatic analysis is mentioned.

The article reports on the outbreak in Connecticut of Shiga toxin-producing Escherichia coli (STEC) infections which is associated with the visits to goat dairy farm in 2016. Topics mentioned include the identified infection by the Department of Public Health (DPH) in Connecticut, the reported experience of bloody diarrhea, and the identify of the STEC 0157 outbreak strains with the farm visits from March 5-24, 2016.