scholarly journals Virulence Factors and Antimicrobial Resistance Patterns of Non-O157 Shiga Toxin-producing Escherichia coli Isolated from Different Sources at Sadat City

Author(s):  
Mohamed Sabry Abd Elraheam Elsyaed ◽  
Mary Mounir

Aims: A great concern directed to non-O157 Shiga toxin-producing Escherichia coli (STEC) serotypes due to their public health importance. Detecting the existence, antimicrobial profiles, and virulence repertoire of different STEC serotypes from animals essential for human food are important. Study Design: This study aimed to investigate the presence of STEC in different hosts, the distribution pattern of stx1, stx2, eaeA, and hlyA genes encoding Shiga toxins 1 and 2, intimin, and enterohemolysin, respectively, and the antimicrobial resistance of the detected serotypes. Results: A total of 75 samples were collected, 20 fecal samples from broilers, 15 fecal samples from ducks, 20 beef samples, and 20 human urine samples. Escherichia coli was detected at a rate of 60/75 (80%) distributed as;17 (85%), 8 (53.3%), 15(75%), and 20 (100%) from broilers, ducks, human urine, and beef samples, respectively. There was a significant difference between the isolation rates of E. coli from different sources with p<0.05. The prevalent serotypes were O78, O2:H6, O15:H2, and O26: H1. The frequency of stx1 gene was 56/60 (93.3%), stx2 gene was 55/60 (91.6%), the eaeA gene was 35/60 (58.3%), and hlyA gene was 26/60 (43.3%). The most effective antimicrobials were amoxicillin/clavulanic acid and ampicillin with the efficacy of 52/60 (86.6%) for each, while the efficacy of chloramphenicol and doxycycline was 5/60 (8.3%) and 44/60 (73.3%), respectively. Conclusion: The high frequency of non-O157 Shiga toxin-Producing Escherichia coli from different samples at Sadat City, high prevalence of virulence factors and resistance to chloramphenicol and doxycycline will help in monitoring the distribution of virulent serotypes and contribute to the establishment of control measures to reduce the spread of infection.

2015 ◽  
Vol 35 (9) ◽  
pp. 775-780 ◽  
Author(s):  
Marcos R.A. Ferreira ◽  
Talícia dos S. Silva ◽  
Ariel E. Stella ◽  
Fabricio R. Conceição ◽  
Edésio F. dos Reis ◽  
...  

Abstract: In order to detect virulence factors in Shiga toxin-producing Escherichia coli (STEC) isolates and investigate the antimicrobial resistance profile, rectal swabs were collected from healthy sheep of the races Santa Inês and Dorper. Of the 115 E. coli isolates obtained, 78.3% (90/115) were characterized as STEC, of which 52.2% (47/90) carried stx1 gene, 33.3% (30/90) stx2 and 14.5% (13/90) both genes. In search of virulence factors, 47.7% and 32.2% of the isolates carried the genes saa and cnf1. According to the analysis of the antimicrobial resistance profile, 83.3% (75/90) were resistant to at least one of the antibiotics tested. In phylogenetic classification grouped 24.4% (22/90) in group D (pathogenic), 32.2% (29/90) in group B1 (commensal) and 43.3% (39/90) in group A (commensal). The presence of several virulence factors as well as the high number of multiresistant isolates found in this study support the statement that sheep are potential carriers of pathogens threatening public health.


2014 ◽  
Vol 77 (8) ◽  
pp. 1269-1274 ◽  
Author(s):  
HIROHISA MEKATA ◽  
ATSUSHI IGUCHI ◽  
KIMIKO KAWANO ◽  
YUMI KIRINO ◽  
IKUO KOBAYASHI ◽  
...  

Bovines are recognized as an important reservoir of Shiga toxin–producing Escherichia coli (STEC). Although STEC strains are significant foodborne pathogens, not all of the STEC held by cattle are pathogenic, and which type of STEC that will become epidemic in humans is unpredictable. Information about the prevalence of serotype and virulence gene distribution in beef cattle is insufficient to develop monitoring and controlling activities for a food safety and security program. Thus, this study investigated the prevalence of O157 and non-O157 STEC in Japanese beef cattle and characterized the isolates by the type of O antigen and several virulence markers to help predict the pathogenicity. In this study, 64.2%(176 of 274) of enrichment cultures of fecal samples collected from an abattoir and farms were stx1 and/or stx2 positive by PCR. STEC strains were isolated from 22.1% (39 of 176) of the positive fecal samples, and these isolates represented 17 types of O antigen (O1, O2 or O50, O5, O8, O55, O84, O91, O109, O113, O136, O150, O156, O157, O163, O168, O174, and O177). Two selective media targeting major STEC groups, cefixime-tellurite sorbitol MacConkey agar and CHROMagar O26/O157, allowed isolation of a variety of STEC strains. The most frequently isolated STEC was O113 (8 of 39), which has previously been reported as a cause of foodborne infections. Although most of the O113 STEC isolated from infected patients possessed the enterohemolysin (hlyA) gene, none of the O113 STEC cattle isolates possessed the hlyA gene. The second most common isolate was O157 (6 of 39), and all these isolates contained common virulence factors, including eae, tir, lpf1, lpf2, and hlyA. This study shows the prevalence of O157 and non-O157 STEC in Japanese beef cattle and the relationship of O antigen and virulotypes of the isolates. This information may improve identification of the source of infection, developing surveillance programs or the current understanding of virulence factors of STEC infections.


2020 ◽  
Vol 68 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Eloisa Sevilla ◽  
Raúl C. Mainar-Jaime ◽  
Bernardino Moreno ◽  
Inmaculada Martín-Burriel ◽  
Mariano Morales ◽  
...  

AbstractThe aim of this study was to estimate the prevalence of antimicrobial resistance (AMR) in Escherichia coli from a dog population in Spain and assess specific virulence factors. Susceptibility to 22 antimicrobials was tested along with the production of extended-spectrum β-lactamases (ESBLs) and AmpC in faecal isolates from 100 dogs. Virulence-related genes associated with attaching and effacing E. coli (eae, Stx1, Stx2) and extraintestinal pathogenic E. coli – ExPEC – (papC, hlyA and cnf1) were detected by PCR. At least one kind of AMR was observed in 73% of the isolates. The highest prevalences corresponded to penicillin (45%), aminoglycoside (40%) and non-extended spectrum cephalosporin (39%) classes. Multidrug resistance (MDR) was observed in 53.4% of the resistant isolates. No resistance to colistin was found. Production of ESBL/AmpC enzymes was detected in 5% of E. coli. Shiga toxin-producing E. coli were not observed, enteropathogenic E. coli were identified in only 12% of them, and ExPEC were found in 25%. Dog faeces can be a source of E. coli strains potentially presenting a threat to humans through their virulence factors or AMR. The non-hygienic keeping of animals may increase the risk of colonisation of such pathogens in humans.


2015 ◽  
Vol 60 (3) ◽  
pp. 1874-1877 ◽  
Author(s):  
S. Baron ◽  
S. Delannoy ◽  
S. Bougeard ◽  
E. Larvor ◽  
E. Jouy ◽  
...  

This study investigated antimicrobial resistance, screened for the presence of virulence genes involved in intestinal infections, and determined phylogenetic groups ofEscherichia coliisolates from untreated poultry and poultry treated with ceftiofur, an expanded-spectrum cephalosporin. Results show that none of the 76 isolates appeared to be Shiga toxin-producingE. colior enteropathogenicE. coli. All isolates were negative for the major virulence factors/toxins tested (ehxA,cdt, heat-stable enterotoxin [ST], and heat-labile enterotoxin [LT]). The few virulence genes harbored in isolates generally did not correlate with isolate antimicrobial resistance or treatment status. However, some of the virulence genes were significantly associated with certain phylogenetic groups.


2002 ◽  
Vol 65 (8) ◽  
pp. 1322-1325 ◽  
Author(s):  
MANSOUR SAMADPOUR ◽  
M. KUBLER ◽  
F. C. BUCK ◽  
G. A. DEPAVIA ◽  
E. MAZENGIA ◽  
...  

Shiga toxin–producing Escherichia coli (STEC) is increasingly recognized as a common cause of diarrhea. STEC infection is a major public health threat because of its ability to cause serious and potentially life-threatening illnesses. The main reservoirs of STEC are believed to be the intestinal tracts of animals. Several studies have investigated the prevalence of STEC in various food items. The objective of this study was to determine the prevalence of STEC in the Seattle ground beef supply. In addition, the relative amount of STEC contamination between stores was compared, and possible differences between types of ground beef based on fat content (9, 16, and 23%) were investigated. A survey of Stx-I and/or Stx-II genes in fecal samples from cattle at a local slaughter house was also conducted. Of 296 ground beef samples tested from area retail grocery stores, 16.8% were positive for the presence of the toxin genes. Our data showed that there was no statistically significant difference (P &gt; 0.05) in the prevalence of STEC between the ground beef samples of different fat contents and between grocery store chains. Of the 103 cattle fecal samples tested, 19 (18.4%) were found positive for the presence of Stx-I and/or Stx-II genes. The presence of a rather high percentage of STEC in the food supply in the absence of large number of cases suggests that not all STEC lineages are pathogenic for humans.


2001 ◽  
Vol 64 (10) ◽  
pp. 1613-1616 ◽  
Author(s):  
B. H. THRAN ◽  
H. S. HUSSEIN ◽  
M. R. HALL ◽  
S. F. KHAIBOULLINA

Shiga toxin–producing Escherichia coli (STEC) produce toxins that have been associated with several human illnesses. E. coli O157:H7 is the most well-studied STEC and was first associated with consumption of improperly cooked ground beef in 1982. E. coli O157:H7 is not the only foodborne STEC because other STEC serotypes are also associated with human illnesses. The objective of this study was to assess prevalence of STEC in 23 yearling beef (Angus) heifers grazing an irrigated grass pasture in spring (April), summer (July), fall (October), and winter (December) of 1999. A total of 86 fecal samples were rectally collected and were subjected to microbiological testing for the presence of STEC. Nine E. coli isolates from five heifers (one in spring and fall and three in winter) were toxic to Vero cells. Of these isolates, four were E. coli O157:H7, two belonged to the serogroup O6, one O39:NM, one O113:H−, and the final isolate was untypable. The STEC prevalence rate in our herd ranged from 4% (spring) to 15% (winter). Based on detecting both O157:H7 and non-O157:H7 STEC in our heifers, it is clear that screening fecal samples should not be limited to E. coli O157:H7. Identification of STEC-positive cattle prior to slaughter should help in reducing the risk of beef contamination with such foodborne pathogens if pre- and/or postharvest control measures are applied to such animals.


2021 ◽  
Vol 41 ◽  
Author(s):  
Bruna R. Arrais ◽  
Ângela V.B.A. Silveira ◽  
Angélica F. Oliveira ◽  
Nayara C. Barbosa ◽  
Ariel E. Stella ◽  
...  

ABSTRACT: The present study was aimed at subtyping of Stx1 and Stx2 genes and characterization of antimicrobial resistance in 106 Shiga toxin-producing Escherichia coli (STEC) strains isolated from cattle and sheep feces. PCR was used to determine the subtypes, and the disk-diffusion method was used to evaluate the antimicrobial resistance. Ten antibiotics from five different classes were tested. Among the isolates of bovine origin, two subtypes of Stx1 (Stx1a and Stx1c), and four subtypes of Stx2 (Stx2a, Stx2b, Stx2c, and Stx2d) were identified. In isolates of sheep origin, two subtypes of Stx1 (Stx1a and Stx1c), and four subtypes of Stx2 (Stx2a, Stx2b, Stx2c, and Stx2 g) were identified. The results obtained suggest the presence of high diversity in Stx1 and Stx2 genes. Further, 96.6% (57/59) of bovine fecal strains and 89.4% (42/47) of sheep fecal strains showed resistance to at least one tested antibiotic. In both animal species, most strains were multidrug-resistant (MDR) (67.8% in cattle and 59.6% in sheep), with no significant difference between host animals. Adult animals were eight times more likely to have STEC with greater pathogenic potential. STEC with the highest pathogenic potential were three times more likely to be multidrug-resistant than STEC with the lowest pathogenic potential. The data reported in this study suggests the occurrence of strains with high potential pathogenicity in the region studied. Therefore, the ruminants of this region are carriers of strains that can cause infections in humans.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Mohamed Sabry Abd Elraheam Elsayed ◽  
Samah Mahmoud Eldsouky ◽  
Tamer Roshdy ◽  
Abeer Mohamed Ahmed Bayoume ◽  
Ghada M. Nasr ◽  
...  

Abstract Background The Shiga toxin-producing Escherichia coli (STEC) represented a great risk to public health. In this study, 60 STEC strains recovered from broiler and duck fecal samples, cow’s milk, cattle beef, human urine, and ear discharge were screened for 12 virulence genes, phenotypic and genotypic antimicrobial resistance, and multiple-locus variable-number tandem-repeat analysis (MLVA). Results The majority of strains harbored Shiga toxin 1 (stx1) and stx1d, stx2 and stx2e, and ehxA genes, while a minority harbored stx2c subtype and eaeA. We identified 10 stx gene combinations; most of strains 31/60 (51.7%) exhibited four copies of stx genes, namely the stx1, stx1d, stx2, and stx2e, and the strains exhibited a high range of multiple antimicrobial resistance indices. The resistance genes blaCTX-M-1 and blaTEM were detected. For the oxytetracycline resistance genes, most of strains contained tetA, tetB, tetE, and tetG while the tetC was present at low frequency. MLVA genotyping resolved 26 unique genotypes; genotype 21 was highly prevalent. The six highly discriminatory loci DI = 0.9138 are suitable for the preliminary genotyping of STEC from animals and humans. Conclusions The STEC isolated from animals are virulent, resistant to antimicrobials, and genetically diverse, thus demands greater attention for the potential risk to human.


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