Serogroups, Virulence Genes and Antibiotic Resistance of Escherichia coli Isolated from Cold Smoked Meat Products and Sprouted Grains in Latvia

Alise Jakovele 1 , Vizma Nikolajeva 2 , Jūlija Trofimova 3  and Natalja Ivanova 4
  • 1 Institute of Food Safety, Animal Health and Environment “BIOR”, LV-1076, Rīga, Latvia
  • 2 Department of Microbiology and Biotechnology, Faculty of Biology, University of Latvia, LV-1004, Rīga, Latvia
  • 3 Institute of Food Safety, Animal Health and Environment “BIOR”, LV-1076, Rīga, Latvia
  • 4 Institute of Food Safety, Animal Health and Environment “BIOR”, LV-1076, Rīga, Latvia


Although the information available on pathogenic Escherichia coli is in abundance, foodborne outbreaks are still a major problem. The aim of this study was to describe E. coli strains isolated from cold smoked meat products (37 samples) and sprouted grains (35 samples), to evaluate their virulence potential (vtx1, vtx2; eaeA), to determine serogroups and antibiotic resistance in Latvia. From the isolates tested 66 samples (91.7%) contained none of the virulence genes, 6 samples (8.3%) contained the eaeA gene, and two samples (2.8%) contained eaeA and vtx1 genes. Eleven samples (29.7%) isolated from meat products belonged to serogroups O103, O121, O145, O142, and O26. Six strains contained the eaeA gene, and four of them belonged to serogroup O103, one to O145, and one to O26. Two strains that additional to eaeA gene were also positive to vtx1 belonged to verotoxigenic O26. 31 samples (88.6%) isolated from sprouted grains belonged to serogroups O103 and O121; however, none of the strains contained any of the virulence genes. From strains isolated from meat products 46.0% were resistant to one to three antibiotics, but all isolates from sprouted grains were susceptible. Two strains showed multi-resistance and also contained the mcr-1 gene that encodes resistance to colistin.

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