Virulence Genes and the Antimicrobial Susceptibility of Escherichia coli, Isolated from Wild Waterbirds, in the Netherlands and Poland.

Abstract

Affiliation to four phylogroups (A, B1, B2, and D) was examined, among 190 Escherichia coli strains, collected from five, wild waterbird species, including the following: the Greylag goose-Anser anser (61) and the Canada goose-Branta canadensis (33) obtained in the Netherlands, and the Mallard-Anas platyrhynchos (38), the Mute swan-Cygnus olor (37), and the Great cormorant-Phalacrocorax carbo (21) obtained in Poland. Moreover, the prevalence of 10 virulence factors: astA, iss, iucD, irp2, papC, tsh, vat, cva/cvi, stx2f, and bfp, as well as antimicrobial susceptibility to amoxicillin, enrofloxacin, and tetracycline (minimum inhibitory concentration [MIC] using E-tests) were investigated, in the examined E. coli strains. Results demonstrated that the greatest number of E. coli strains belonged to phylogenetic groups, B1 (86 strains-45.3%) and D (49 strains-25.8%), whereas 40 (21.0%) and only 15 (7.9%) isolates were classified as being of phylogenetic groups, A and B2, respectively. Among the 10 tested virulence-associated genes, 7 genes were detected in 61 examined strains (32.1%) with highly varying frequency. Virulence profiles showed that astA, iss, and irp2 genes were detected most frequently among all examined E. coli strains, isolated from every chosen bird species. Antimicrobial susceptibility, as detected by MIC for the examined antibiotics, is variable among strains isolated from different species of birds. The aim of this study was to examine the prevalence of E. coli strains, isolated from different species of wild waterbirds and determine their potential pathogenicity to the environment, other birds, and people.