Population structure and attribution of human clinical Campylobacter jejuni isolates from central Europe to livestock and environmental sources.

Campylobacter jejuni is among the most prevalent causes of human bacterial gastroenteritis worldwide. Domesticated animals and, especially, chicken meat are considered to be the main sources of infections. However, the contribution of surface waters and wildlife in C. jejuni transmission to humans is not well understood. We have evaluated the source attribution potential of a six-gene multiplex PCR (mPCR) method coupled with STRUCTURE analysis on a set of 410 C. jejuni strains isolated from environment, livestock, food and humans in central Europe. Multiplex PCR fingerprints were analysed using Subclade prediction algorithm to classify them into six distinct mPCR clades. A subset of C. jejuni isolates (70%) was characterized by multilocus sequence typing (MLST) demonstrating 74% congruence between mPCR and MLST. The correspondence analysis of mPCR clades and sources of isolation indicated three distinct groups in the studied C. jejuni population-the first one associated with isolates from poultry, the second one with isolates from cattle, and the third one with isolates from the environment. The STRUCTURE analysis attributed 7.2% and 21.7% of human isolates to environmental sources based on MLST and mPCR fingerprints, respectively.

Virulence and antimicrobial resistance determinants of verotoxigenic Escherichia coli (VTEC) and of multidrug-resistant E. coli from foods of animal origin illegally imported to the EU by flight passengers.

The aim of this study was to reveal phenotype/genotype characteristics of verotoxigenic Escherichia coli (VTEC) and multidrug resistant E. coli in food products of animal origin confiscated as illegal import at Austrian, German and Slovenian airports. VTEC isolates were obtained by using ISO guidelines 16654:2001 for O157 VTEC or ISO/ TS13136:2012 for non-O157 VTEC, with additional use of the RIDASCREEN® Verotoxin immunoassay. The testing of 1526 samples resulted in 15 VTEC isolates (1.0%) primarily isolated from hard cheese from Turkey and Balkan countries. Genotyping for virulence by using a miniaturized microarray identified a wide range of virulence determinants. One VTEC isolate (O26:H46) possessing intimin (eae) and all other essential genes of Locus of Enterocyte Effacement (LEE) was designated as enterohemorrhagic E. coli (EHEC). None of the other VTEC strains belonged to serogroups O157, O145, O111, O104 or O103. VTEC strains harbored either stx(1) (variants stx1(a) or stx(1c)) or st(x2) (variants stx(2a), stx(2b), stx(2a/d) or stx(2c/d)) genes. Pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) demonstrated high genetic diversity and identified three new sequence types (STs): 4505, 4506 and 4507. Food samples collected from the Vienna airport were also tested for E. coli quantities using the ISO 16649:2001, and for detection of multidrug resistant phenotypes and genotypes. The resulting 113 commensal E. coli isolates were first tested in a pre-screening against 6 selected antimicrobials to demonstrate multidrug resistance. The resulting 14 multidrug resistant (MDR) E. coli isolates, representing 0.9% of the samples, were subjected to further resistance phenotyping and to microarray analyses targeting genetic markers of antimicrobial resistance and virulence. Genotyping revealed various combinations of resistance determinants as well as the presence of class 1, class 2 integrons. The isolates harbored 6 to 11 antibiotic resistance genes as well as 1 to 14 virulence genes. In this panel of 14 MDR E. coli two strains proved to carry CTX-M type ESBLs, and one single isolate was identified as enteropathogenic E. coli (EPEC). In general, isolates carrying a high number of resistance determinants had lower number of virulence genes and vice versa. In conclusion, this first pilot study on the prevalence of VTEC and of MDR/ESBL E. coli in illegally imported food products of animal origin suggests that these strains could represent reservoirs for dissemination of potentially new types of pathogenic and MDR E. coli in Europe.

The evidence for clonal spreading of quinolone resistance with a particular clonal complex of Campylobacter jejuni.

Campylobacter is the most prevalent cause of bacterial gastroenteritis worldwide and it represents a significant public health risk of increasing severity due to its escalating resistance to clinically important quinolone and macrolide antibiotics. As a zoonotic pathogen Campylobacter is transmitted along the food chain and naturally cycles from environmental waters, feedstuff, animals and food to humans. We determined antibiotic resistance profiles, as well as multilocus sequence types and flaA-SVR types for 52 C. jejuni isolated in Slovenia from human, animal, raw and cured chicken meat and water samples. Twenty-eight different sequence types, arranged in ten clonal complexes, three new allele types and five new sequence types were identified, indicating the relatively high diversity in a small group of strains. The assignment of strains from different sources to the same clonal complexes indicates their transmission along the food supply chain. The most prevalent clonal complex was CC21, which was also the genetic group with 95% of quinolone-resistant strains. Based on the genetic relatedness of these quinolone-resistant strains identified by polymerase chain reaction with a mismatch amplification mutation assay and sequencing of the quinolone resistance-determining region of the gyrA gene, we conclude that the high resistance prevalence observed indicates the local clonal spread of quinolone resistance with CC21.

Cutaneous listeriosis in a veterinarian with the evidence of zoonotic transmission--a case report.

A case of Listeria monocytogenes skin infection in a man is presented. A 54-year-old male veterinary practitioner developed pustular changes on the skin of arms and hands after assisting with the delivery of a stillborn calf. Listeria monocytogenes was isolated from the skin lesions on the arms and from the bovine placenta. Listeria monocytogenes isolates were serotyped and genotyped with pulsed-field gel electrophoresis (PFGE) to confirm the suspected transmission of the pathogen from animal to human. All isolates were of serotype 4b with identical pulsotype. To the best of our knowledge, this is the first case of cutaneous listeriosis in which the evidence for zoonotic transmission of L. monocytogenes is supported by genotyping methods.