Detection of multidrug-resistant Shiga toxin-producing Escherichia coli in some food products and cattle faeces in Al-Sharkia, Egypt: one health menace

Abstract

Background Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathogen, that is transmitted from a variety of animals, especially cattle to humans via contaminated food, water, feaces or contact with infected environment or animals. The ability of STEC strains to cause gastrointestinal complications in human is due to the production of Shiga toxins (sxt). However, the transmission of multidrug-resistance STEC strains are linked with a severity of disease outcomes and horizontal spread of resistance genes in other pathogens. The result of this has emerged as a significant threat to public health, animal health, food safety, and the environment. Therefore, the purpose of this study is to investigate the antibiogram profile of enteric E. coli O157 isolated from food products and cattle faeces samples in Zagazig City, Al-Sharkia, Egypt, and to reveal the presence of Shiga toxin genes stx1 and stx2 as virulence factors in multidrug-resistant isolates. In addition to this, the partial 16S rRNA sequencing was used for the identification and genetic recoding of the obtained STEC isolates. Results There was a total of sixty-five samples collected from different geographical regions at Zagazig City, Al-Sharkia—Egypt, which were divided into: 15 chicken meat (C), 10 luncheon (L), 10 hamburgers (H), and 30 cattle faeces (CF). From the sixty-five samples, only 10 samples (one from H, and 9 from CF) were identified as suspicious E. coli O157 with colourless colonies on sorbitol MacConkey agar media with Cefixime- Telurite supplement at the last step of most probable number (MPN) technique. Eight isolates (all from CF) were identified as multidrug-resistant (MDR) as they showed resistance to three antibiotics with multiple antibiotic resistance (MAR) index ≥ 0.23, which were assessed by standard Kirby-Bauer disc diffusion method. These eight isolates demonstrated complete resistance (100%) against amoxicillin/clavulanic acid, and high frequencies of resistance (90%, 70%, 60%,60%, and 40%) against cefoxitin, polymixin, erythromycin, ceftazidime, and piperacillin, respectively. Those eight MDR E. coli O157 underwent serological assay to confirm their serotype. Only two isolates (CF8, and CF13), both from CF, were showed strong agglutination with antisera O157 and H7, as well as resistance against 8 out of 13 of the used antibiotics with the highest MAR index (0.62). The presence of virulence genes Shiga toxins (stx1 and stx2) was assessed by PCR technique. CF8 was confirmed for carrying stx2, while CF13 was carrying both genes stx1, and stx2. Both isolates were identified by partial molecular 16S rRNA sequencing and have an accession number (Acc. No.) of LC666912, and LC666913 on gene bank. Phylogenetic analysis showed that CF8, and CF13 were highly homologous (98%) to E. coli H7 strain, and (100%) to E. coli DH7, respectively. Conclusion The results of this study provides evidence for the occurrence of E. coli O157:H7 that carries Shiga toxins stx1 and/or stx2, with a high frequency of resistance to antibiotics commonly used in human and veterinary medicine, in Zagazig City, Al-Sharkia, Egypt. This has a high extent of public health risk posed by animal reservoirs and food products with respect to easy transmission causing outbreaks and transfer resistance genes to other pathogens in animal, human, and plants. Therefore, environmental, animal husbandry, and food product surveillance, as well as, clinical infection control, must be strengthened to avoid the extra spread of MDR pathogens, especially MDR STEC strains.

Pathogenic E. coli in the Food Chain across the Arab Countries: A Descriptive Review

“…Shiga toxin-producing E. coli (STEC) carrying Stx1 and Stx2 are significant pathogens with global implications, known for their association with various human illnesses. These illnesses include diarrhea, bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS) [73]. Ruminants, particularly cattle, are recognized as the primary reservoir for STEC, and it can spread to humans through contaminated food and water sources [74].…”

“…One of the key virulence factors is Shiga toxin, which plays a pivotal role in the development of severe symptoms like HUS. Shiga toxin can be categorized into two primary types: Shiga toxin 1 (stx1) and Shiga toxin 2 (stx2) [73]. These toxins are central to the pathogenicity of STEC and the associated illnesses in humans.…”

Molecular detection of Shiga toxin and extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli isolates from sheep and goats

“…They are a large and diverse group of bacteria that infects both humans and animals [ 1 ]. The Shiga toxin ( Stx )-producing Escherichia coli (STEC) is an important zoonotic foodborne pathogen causing gastrointestinal complications in humans [ 2 ]. The term STEC refers to a pathotype of E. coli that produces Stx1 and/or Stx2 [ 2 , 3 ].…”

“…The Shiga toxin ( Stx )-producing Escherichia coli (STEC) is an important zoonotic foodborne pathogen causing gastrointestinal complications in humans [ 2 ]. The term STEC refers to a pathotype of E. coli that produces Stx1 and/or Stx2 [ 2 , 3 ]. There are two major families of Shiga toxins ( Stx ), Stx1 and Stx2 , with 70 percent similar amino acid sequences [ 2 , 4 ].…”

“…The term STEC refers to a pathotype of E. coli that produces Stx1 and/or Stx2 [ 2 , 3 ]. There are two major families of Shiga toxins ( Stx ), Stx1 and Stx2 , with 70 percent similar amino acid sequences [ 2 , 4 ]. It is less likely that Stx1 will produce diseases in humans, while Stx2 is more likely to cause diseases like hemorrhagic colitis (HC) and hemolytic-uremic syndrome (HUS) [ 5 ].…”