Résumé
Aim: The present study was conducted to detect the occurrence, serogroups, virulence genes and phylogenetic relationship of shiga toxin-producing Escherichia coli [STEC] in human, clave and goat in Kerman [southeast of Iran]
Background: STEC have emerged as the important foodborne zoonotic pathogens causing human gastrointestinal disease and confirming the risk to public health
Methods: A total of 671 fecal samples were collected from diarrheic patients [n=395] and healthy calves [n=156] and goats [n=120] and screened for the presence of stx gene. Furthermore, the prevalence of stx1 and stx2 variants, serotypes [O157, O145, O103, O26, O111, O91, O128, and O45], phylogenetic groups and the presence of ehxA, eae, hylA, iha and saa virulence genes were studied
Results: Prevalence of STEC in human diarrheic isolates was 1.3% [5 isolates], in claves was 26.3% [41 isolates] and in goats was 27.5% [33 isolates]. stx1 gene was the most prevalent variant and detected in 75 isolates. Furthermore, stx1c was the most predominant stx subtype, found in 56 isolates. The ehxA identified in 36 [45.6%] isolates, followed by iha 5 [6.3%], eaeA 4 [5.1%], hlyA 2 [2.5%] and saa 2 [2.5%]. Most of the isolates belonged to phylogroup B1. Only two O26 and one O91 isolates were detected in our study
Conclusion: Our results show that STEC strains were widespread among healthy domestic animals in the southeast of Iran
Résumé
The aims of this study were to investigate the phenotypic and genotypic of extended-spectrum beta-lactamase [ESBL] and metallo-beta-lactamases [MBLs] and determine phylogenetic background E. coli isolates from fecal samples of patients with diarrhea in Kerman, southeast of Iran The emergence of ESBLs and MBLs-producing E. coli caused problems in antibiotic treatments. E. coli strains can be assigned to four main phylog-groups, including: A, B1, B2 and D. E. coli isolates [n=216] were obtained from fecal samples of patients with diarrhea between June and December 2013. ESBLs and MBLs were confirmed by disk-diffusion and broth micro-dilution methods. Using PCR, the ESBL-positive isolates were screened to determine the phylo-groups and the presence of bla[CTX-M-15], bla[OXA-1], bla[PER-1], bla[VIM]and bla[IMP] genes. ESBL-positive isolates [n= 56] were detected. Among ESBL-positive isolates, 51 isolates were positive for bla[CTX-M15] and one isolate was positive for both bla[CTX-M-15] and bla[OXA-1] genes. None of the isolates were positive for bla[PER-1], bla[VIM]and bla[IMP] genes. PCR assay for phylotyping of isolates indicated that the isolates were belonged to groups A [54.16%], B1 [11.11%], B2 [12.96%] and D [21.75%]. The isolates possessed bla[CTX-M-15] gene were belonged to A [35 isolates], B1 [5], B2 [3] and D [8] phylo-groups. Our results indicate that bla[CTX-M-15] gene is widespread among diarrheagenic E. coli isolates. ESBLproducing E. coli isolates were disseminated among a diversity of phylo-groups. Further studies are necessary to identify the ESBL genes in relation to phylogenetic groups