Prevalence, Antimicrobial Resistance, and Whole Genome Sequencing Analysis of Shiga Toxin-Producing Escherichia coli (STEC) and Enteropathogenic Escherichia coli (EPEC) from Imported Foods in China during 2015–2021

Abstract

Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic Escherichia coli (EPEC) are foodborne pathogens that cause hemolytic uremic syndrome and fatal infant diarrhea, respectively, but the characterization of these bacteria from imported food in China are unknown. A total of 1577 food samples from various countries during 2015–2021 were screened for STEC and EPEC, and the obtained isolates were tested for antimicrobial resistance and whole genome sequencing analysis was performed. The prevalence of STEC and EPEC was 1.01% (16/1577) and 0.51% (8/1577), respectively. Antimicrobial resistances to tetracycline (8%), chloramphenicol (8%), ampicillin (4%), ceftazidime (4%), cefotaxime (4%), and trimethoprim-sulfamethoxazole (4%) were observed. The antimicrobial resistance phenotypes corresponded with genotypes for most strains, and some resistance genes were related to mobile genetic elements. All 16 STEC isolates were eae negative, two solely contained stx1 (stx1a or stx1c), 12 merely carried stx2 (stx2a, stx2d, or stx2e), and two had both stx1 and stx2 (stx1c + stx2b, stx1a + stx2a + stx2c). Although they were eae negative, several STEC isolates carried other adherence factors, such as iha (5/16), sab (1/16), and lpfA (8/16), and belonged to serotypes (O130:H11, O8:H19, and O100:H30) or STs (ST297, ST360), which have caused human infections. All the eight EPEC isolates were atypical EPEC; six serotypes and seven STs were found, and clinically relevant EPEC serotypes O26:H11, O103:H2, and O145:H28 were identified. Two STEC/ETEC (enterotoxigenic E. coli) hybrids and one EPEC/ETEC hybrid were observed, since they harbored sta1 and/or stb. The results revealed that food can act as a reservoir of STEC/EPEC with pathogenic potential, and had the potential ability to transfer antibiotic resistance and virulence genes.

Detection and Antimicrobial Resistance Profile of Enteropathogenic (EPEC) and Shigatoxigenic Escherichia coli (STEC) in Conventional and Organic Broiler Chickens

“…Moreover, the frequency of these diarrheagenic strains in poultry or carcasses was higher than that found in other studies. Hence, EPEC strains continue to be the most prevalent when compared to STEC strains (Dutta et al, 2011;Alonso et al, 2012;Samanta et al, 2015;Badi et al, 2018;Cerutti et al, 2020;Shen et al, 2022), which was corroborated by the same reports. Nonetheless, this differs from reports by Nagwa et al, (2022), where 30% of STEC and 10% of EPEC were found.…”

Occurrence of Escherichia coli Pathotypes in Diarrheic Calves in a Low-Income Setting

“…This result was in line with Awad et al [ 41 ] who reported ETEC/STEC (14.7%) and ETEC/EPEC (2.7%) in diarrheic calves in Egypt. Other researchers showed that diarrheic calves could be infected with a hybrid STEC-ETEC pathotype [ 50 , 51 ]. These pathogroups are characterized as hetero-pathotypes comprised of virulence genes representing two or more E. coli pathotypes [ 52 ].…”

Detection of hemolytic Shiga toxin-producing Escherichia coli in fresh vegetables and efficiency of phytogenically synthesized silver nanoparticles by Syzygium aromaticum extract and gamma radiation against isolated pathogens

“…Foodborne organisms such as Shiga toxin-producing E. coli (STEC) can cause watery, bloody diarrhea, hemorrhagic colitis, and potentially fatal hemolytic uremic syndrome (HUS). Shiga toxins are divided into two subfamilies, Stx1 and Stx2 , and are encoded by stx1 and stx2 are the primary virulence factors of STEC [ 1 ]. They are pathogenic by adhering to and causing effacement lesions in the intestinal microvilli of the host cell.…”