Prevalence of virulence genes among Escherichia coli strains isolated from food and carcass swabs of different animal origins in Croatia

Abstract

Introduction Escherichia coli is present in the normal intestinal flora but some strains can cause intestinal and extraintestinal diseases, and research on its presence in food of animal origin is in the interests of public health. This study was designed to characterise E. coli strains according to their origin, their carriage of virulence genes specific for certain pathogroups, and phylogenetic group affiliation. Material and Methods The study was carried out on 100 E. coli strains isolated from food samples of various animal origin as well as pig and cattle carcass swabs. Isolation of the strains was performed using two methods. One method included colony count and the other an overnight enrichment of the samples. Isolation was followed by DNA extraction and detection of virulence genes and phylogenetic group with conventional and multiplex PCRs. Results In this study, the most prevalent gene was EAST1 (20%) and strains which carried it were identified as enteroadherent E. coli. Other pathogroups were represented in lower incidences. Phylogenetic group analysis revealed the prevalence of the A and B1 groups, with B1 mainly present in game and cattle strains, while the majority of pig and poultry strains were assigned to group A. Conclusion This study provides an overview of the presence of potentially pathogenic strains and E. coli phylogenetic groups in Croatia, for which the data are limited. Further microbiological and molecular research is required to examine the epidemiological situation in the country.

Whole Genome Sequencing Reveals High Genetic Diversity, Diverse Repertoire of Virulence-Associated Genes and Limited Antibiotic Resistance Genes among Commensal Escherichia coli from Food Animals in Uganda

“…The isolates belonged to two main phylogroups, A and B1, unlike the predominance of B2 which is commonly reported in human pathogenic E. coli , especially the ExPEC but also those of intestinal disease agents. These findings are consistent with other studies [ 18 , 40 , 41 ] that have reported predominance of phylogroups A and B1 in food animals.…”

Molecular identification of blaTEM and blaCTX-M genes in multidrug-resistant Escherichia coli found in milk samples from dairy cattle farms in Tulungagung, Indonesia

“…Escherichia coli is a bacterial species that typically lives in both human and animal digestive tracts. However, under some conditions, E. coli can spread outside of the digestive system ( 21 ). Numerous studies have shown that milk is an advantageous medium for the growth of E. coli and that an overabundance of these bacteria in this foodstuff can be harmful to the general public’s health ( 18 , 28 ).…”