scholarly journals Detection of shiga toxin producing Escherichia coli isolated from children and cattle using PCR technique

2010 ◽  
Vol 9 (3) ◽  
pp. 76
Author(s):  
H. N. A'aiz, And F. A. Abdulla A. H. Al- Hama
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Dna Marker ◽  
Hospitalized Children ◽  
Bacterial Isolates ◽  
Macconkey Agar ◽  
Biochemical Tests ◽  
Fecal Samples ◽  
E Coli ◽  
Stx2 Gene

This study was undertaken to detect STEC isolates, gene(Stx2) in Escherichia coli isolatesand characterize them by biochemical tests , enterohemolysin production and PCR.During aperiod of seven months (November 2007 to May 2008), a total of 280 fecal samples werecollected from 120 hospitalized children suffering from diarrhea and 160 cattle fecal samples .Feces specimens were screened for the presence of NSF E. coli and STEC by cultured onsorbitol MacConkey agar (SMAC).A total of 209 (74.6%) non-sorbitol fermenting (NSF)bacterial isolates were obtained , 69 (57.5%) from children fecal samples and 140 (87.5%) fromcattle feces . Of which 5 (4.16%) NSF E. coli isolated from children fecal samples and 38(23.75%) from cattle feces. NSF isolates were identified as Shiga toxin producing E. coli(STEC), but only 16 (10%) isolates of cattle and 2 (1.6%)isolates of children were PCR-positivefor (Stx2) gene which gave amplification bands at 346 bp using DNA marker in the interpretationof the results. Among 18 STEC studied, a total of 16 (88.8%) isolates expressed enterohemolysinon washing sheep blood agar plates.On the other hand, the study was showed that the sensitivityand specificity of PCR technique in diagnosis of STEC were 41.8% , 100% respectively, incomparison with other tests like biochemical tests, sensitivity and specificity of these tests were(100% , 86.9%) respectively.

Prevalence and Molecular Characterization of Escherichia coli O157:H7 in Bulk Tank Milk and Fecal Samples from Cull Cows: A 12-Month Survey of Dairy Farms in East Tennessee

2002 ◽  
Vol 65 (5) ◽  
pp. 752-759 ◽  
Author(s):  
S. E. MURINDA ◽  
L. T. NGUYEN ◽  
S. J. IVEY ◽  
B. E. GILLESPIE ◽  
R. A. ALMEIDA ◽  
...  
Keyword(s):  
Shiga Toxin ◽  
Dairy Farms ◽  
Escherichia Coli O157 ◽  
Bacterial Isolates ◽  
Macconkey Agar ◽  
Bulk Tank Milk ◽  
Fecal Samples ◽  
E Coli ◽  
Milk Samples ◽  
Bulk Tank

A study on the prevalence of Escherichia coli O157:H7 was conducted on 30 dairy farms in east Tennessee between May 2000 and April 2001. This pathogen was isolated from 8 of 30 (26.7%) dairy farms at various sampling times. A total of 415 fecal samples from cull dairy cows and 268 bulk tank milk samples were analyzed. Overall, 10 of 683 (1.46%) samples (2 of 268 [0.75%] milk samples and 8 of 415 [1.93%] fecal samples) tested positive for E. coli O157:H7. Food and Drug Administration Bacteriological Analytical Manual protocols were used for the conventional isolation and confirmation of E. coli O157:H7. Samples were shake cultured (150 rpm) at 42°C for 24 h in tryptic soy broth containing 2 mg of novobiocin per liter. White colonies isolated on cefixime-tellurite sorbitol MacConkey agar plates were evaluated for fluorescence on sorbitol MacConkey agar supplemented with 0.025 g of methylumbelliferyl-β-d-glucuronide per liter. Nonfluorescing white colonies were biochemically typed and serologically confirmed. Multiplex polymerase chain reaction profiles of E. coli O157: H7 isolates indicated the presence of common virulence factors (Shiga toxin, enterohemolysin, and intimin) of Shiga toxin–producing E. coli, suggesting the potential human pathogenicity of bacterial isolates. Pulsed-field gel electrophoresis profiles of SpeI and XbaI restriction enzyme–digested genomic DNA were used to establish relatedness among bacterial isolates. Data from this study indicate that both cull dairy cows and bulk tank milk pose a potential hazard with regard to human foodborne illness. It is therefore imperative to develop on-farm and preharvest pathogen reduction programs to control the carriage of E. coli O157:H7 pathogens.

scholarly journals Prevalence of enterotoxigenic and Shiga toxin-producing Escherichia coli in pigs slaughtered in Mato Grosso, Brazil

2010 ◽  
Vol 5 (02) ◽  
pp. 123-127 ◽  
Author(s):  
Rodrigo Prado Martins ◽  
Maria Cristina Da Silva ◽  
Valeria Dutra ◽  
Luciano Nakazato ◽  
Domingos da Silva Leite
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Enterotoxigenic Escherichia Coli ◽  
Future Research ◽  
Macconkey Agar ◽  
Mato Grosso ◽  
E Coli ◽  
Pcr Assays ◽  
Porcine Origin ◽  
Stx2 Gene

Introduction: This study aimed to estimate the prevalence of enterotoxigenic Escherichia coli (ETEC) and Shiga toxin-producing Escherichia coli (STEC) strains in pigs slaughtered in abattoirs located in the state of Mato Grosso, Brazil. Methodology: Intestinal samples from 74 animals were aseptically dissected and lumen content was plated on MacConkey agar. Confluent colonies from each plate were screened for the presence of ETEC and STEC strains by PCR assays. Results: It was verified that the prevalence of STEC and ETEC carriers was 1.35% and 9.46% respectively. One (1.35%) of the 74 samples tested was positive for the stx2 gene, and seven (9.46%) for st1, of which two (2.70%) were also positive for lt1. Conclusion: The results provided represent a benchmark for future research on pathogenic E. coli of porcine origin in Mato Grosso. 

Prevalence of non-O157 Shiga Toxin-producing E. Coli in Children and Calves in Al- Muthanna Province, Iraq

2021 ◽  
Vol 14 (2) ◽  
pp. 78-90
Author(s):  
Ahmed Jarad ◽  
Kh. Al- Jeboori
Keyword(s):  
Shiga Toxin ◽  
Latex Agglutination ◽  
Macconkey Agar ◽  
Biochemical Tests ◽  
Bacteriological Study ◽  
E Coli ◽  
Additional Information ◽  
Single Colony ◽  
Big Six ◽  
Reliable Isolation

The present study focus on non-O157 Shiga toxin-producing E. Coli (STEC), included a bacteriological study was subjected to provide additional information for non-O157 STEC prevalence in children and calves. Isolation by using selective culturing media (CHROMagar STEC and CHROMagar O157) from 127 children suffering from diarrhea and 133 calves in Al- Muthanna province. Characterization depends on culturing positive colony on MacConkey agar and Levin’s Eosin Methylene blue agar, staining single colony from the growth by gram stain, biochemical tests; Indole, the Methyl Red, Voges-Proskauer, Citrate test, Oxidase, Catalase, Urease, Motility, Kligler Iron and Api-20E, were done to confirm a diagnosis of non-O157 STEC, The reliable isolation as non-O157 STEC serotyping by specific latex agglutination test for the target non-O157 STEC (big six) serogroup (O26, O45, O103, O111, O121 and O145). The current study showed the prevalence of non-O157 STEC was 20 of out 127 (15.73%) in samples collected from children and 27 / 133 (20.30%) in calves samples in conclusion the Non-O157 STEC is an important cause of diarrhea in children, and calves; finally, the calves play an important reservoir for Non-O157 STEC.

scholarly journals Prevalence and molecular detection of shiga toxin producing Escherichia coli from diarrheic cattle

2016 ◽  
Vol 14 (1) ◽  
pp. 63-68 ◽  
Author(s):  
MM Akter ◽  
S Majumder ◽  
KH MNH Nazir ◽  
M Rahman
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Molecular Detection ◽  
Chain Reaction ◽  
Specific Primers ◽  
Fecal Samples ◽  
E Coli ◽  
Uremic Syndrome ◽  
Polymerase Chain ◽  
Positive Isolate

Shiga toxin-producing Escherichia coli (STEC) are zoonotically important pathogen which causes hemorrhagic colitis, diarrhea, and hemolytic uremic syndrome in animals and humans. The present study was designed to isolate and identify the STEC from fecal samples of diarrheic cattle. A total of 35 diarrheic fecal samples were collected from Bangladesh Agricultural University (BAU) Veterinary Teaching Hospital. The samples were primarily examined for the detection of E. coli by cultural, morphological and biochemical characteristics, followed by confirmation of the isolates by Polymerase Chain Reaction (PCR) using gene specific primers. Later, the STEC were identified among the isolated E. coli through detection of Stx-1 and Stx-2 genes using duplex PCR. Out of 35 samples, 25 (71.43%) isolates were confirmed to be associated with E. coli, of which only 7 (28%) isolates were shiga toxin producers, and all of them were positive for Stx-1. However, no Stx-2 positive isolate could be detected. From this study, it may be concluded that cattle can act as a reservoir of STEC which may transmit to human or other animals.J. Bangladesh Agril. Univ. 14(1): 63-68, June 2016

Comparison of a New Enrichment Procedure for Shiga Toxin–Producing Escherichia coli with Five Standard Methods

2005 ◽  
Vol 68 (8) ◽  
pp. 1593-1599 ◽  
Author(s):  
MICHAEL A. GRANT
Keyword(s):  
Escherichia Coli ◽  
Real Time ◽  
Shiga Toxin ◽  
Real Time Pcr ◽  
Target Cells ◽  
Macconkey Agar ◽  
Standard Methods ◽  
E Coli ◽  
Canadian Health ◽  
Health Products

A new procedure for enrichment of Escherichia coli O157:H7 and other Shiga toxin–producing E. coli was compared to five standard methods: the British Public Health Laboratory Service, International Standard Method, U.S. Department of Agriculture, Canadian Health Products and Food Branch, and U.S. Food and Drug Administration. The new procedure was comparable to the standard methods in its ability to detect target cells inoculated into foods at approximately 1 CFU g−1. Comparisons were also made of the ability of the six enrichment procedures to detect E. coli O157:H7 against a large background of competitor microorganisms. In these experiments the new procedure yielded more target cells than the other five enrichments by two to three orders of magnitude as determined by enumeration on sorbitol MacConkey agar with tellurite and cefixime and Rainbow agar with tellurite and novobiocin and by verification of presumptive colonies by real-time PCR. For example, the population of enterohemorrhagic E. coli strain 6341 recovered on sorbitol MacConkey agar with tellurite and cefixime after enrichment with the experimental method was 2.42 × 108 CFU ml−1 and 1.80 × 106 CFU ml−1 after enrichment with the Canadian Health Products and Food Branch method, the second most effective in this experiment. In addition, broth cultures resulting from each of the six enrichment procedures were used to prepare templates for real-time PCR detection of stx1/stx2. Resulting threshold cycle (Ct) values after the experimental enrichment were similar to positive control values, whereas the five standard methods produced delayed Ct values or were not detected.

scholarly journals Antibiotic Resistance of Sorbitol Non-Fermenting Shiga Toxin Producing Escherichia coli Isolated from Buffaloes

2021 ◽  
Vol 10 (1) ◽  
pp. 51-54
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Veterinary Medicine ◽  
Nalidixic Acid ◽  
Shiga Toxin ◽  
Emerging Pathogen ◽  
E Coli ◽  
Antibiotic Resistance Profile ◽  
Reservoir Species ◽  
Stx2 Gene

Sorbitol non-fermenting Shiga toxin producing Escherichia coli (SNF-STEC) is considered as a significant emerging pathogen. Though, cattle and buffaloes are the chief reservoir, species like goat, sheep, deer and other ruminants can also harbor this pathogen. Therefore, this pathogen can easily be transmitted to human and other animals through food chain and their environment. The present study, aimed to ascertain the antibiotic resistance profile of SNF-STEC isolates from buffaloes as well as to detect the resistance genes. A total of 33 sorbitol non-fermenting (SNF) E. coli isolates were tested against ten commonly used antibiotics both in human and veterinary medicine. Results revealed that 78.8% isolates were resistant to sulfamethoxazole-trimethoprim and nalidixic acid whereas 60.6% to tetracycline and 48.5% to doxycycline. The majority of the isolates were found sensitive to both gentamycin and ciprofloxacin (90%) followed by erythromycin (66.7%) and ceftriaxone (51.5%). Of 33 SNF E. coli, 12 were STEC harboring both stx1 and stx2 gene that dictated 66.7% isolates were found resistant to sulfamethoxazole-trimethoprim and nalidixic acid followed by ampicillin (58.3%) and tetracycline (58.3%). blaTEM was detected in 66.7% ampicillin resistant isolates and sul2 was exposed in 34.6% sulfamethoxazole-trimethoprim resistant isolates. sul1 gene was negative for the sulfamethoxazole-trimethoprim resistant isolates.

scholarly journals Detection of auto-transporter Sat and Vat genes among Escherichia coli strains isolated from urinary tract infections

2019 ◽  
Vol 23 (10) ◽  
pp. 40 ◽  
Author(s):  
Wisal R. Yaseen AL- Hayali1 ◽  
Alaa Younis Mahdy2 ◽  
Muhammad Abdul Zaraq Ibrahim3
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Urinary Tract Infections ◽  
Duplex Pcr ◽  
Macconkey Agar ◽  
Biochemical Tests ◽  
E Coli ◽  
Genes Encoding ◽  
Tract Infections ◽  
Pcr Techniques

This study was designed to detect the presence of genes encoding autotranspoter proteins in E. coli that causes UTI by using PCR techniques. Seventy two urine sample were collected from patients infected with UTI whom attended to Salah-AL-deen general hospital in Tikrit city, during three months period (September to November 2016). All samples were cultivated on Blood agar and MacConkey agar. The 47(65.2%) E. coli isolates were confirmed using standard biochemical tests for E. coli. The results indicate the frequencies of Sat gene was 27 strains(57.5%) while Vat gene was 12 strains (25.5%) while the Duplex PCR detected 8(17%) strains of E. coli contained two genes. With this method, we confirmed that autotransporter genes are pathospecifically distributed among the E. coli strains studied.   http://dx.doi.org/10.25130/tjps.23.2018.167

scholarly journals Selective Isolation of eae-Positive Strains of Shiga Toxin-Producing Escherichia coli

2000 ◽  
Vol 38 (4) ◽  
pp. 1684-1687 ◽  
Author(s):  
Hiroshi Fukushima ◽  
Ken Hoshina ◽  
Manabu Gomyoda
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Acid Resistance ◽  
Selective Isolation ◽  
Macconkey Agar ◽  
Tellurite Resistance ◽  
E Coli

Culture on cefixime, tellurite, and sorbitol-MacConkey agar after HCl treatment facilitated the growth of 410 (94%) of 436eae-positive Shiga toxin-producing Escherichia coli (STEC) strains and 17 (16%) of 107 eae-negative STEC strains. This selectivity was closely related to acid resistance in E. coli and tellurite resistance ineae-positive STEC strains.

Escherichia coli O157 and non-O157 Shiga Toxin–Producing Escherichia coli in Fecal Samples of Finished Pigs at Slaughter in Switzerland

2006 ◽  
Vol 69 (2) ◽  
pp. 260-266 ◽  
Author(s):  
M. KAUFMANN ◽  
C. ZWEIFEL ◽  
M. BLANCO ◽  
J. E. BLANCO ◽  
J. BLANCO ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Escherichia Coli O157 ◽  
Strongly Correlated ◽  
Fecal Samples ◽  
E Coli ◽  
High Prevalence ◽  
Strain Testing ◽  
Typical Epec ◽  
Uremic Syndrome

Fecal samples from 630 slaughtered finisher pigs were examined by PCR to assess the shedding of Escherichia coli O157 (rfbE) and Shiga toxin–producing E. coli (STEC, stx). The proportion of positive samples was 7.5% for rfbE and 22% for stx. By colony hybridization, 31 E. coli O157 and 45 STEC strains were isolated, and these strains were further characterized by phenotypic and genotypic traits. Among E. coli O157 strains, 30 were sorbitol positive, 30 had an H type other than H7, and none harbored stx genes. Intimin (eae), enterohemolysin (ehxA), EAST1 (astA), and porcine A/E–associated protein (paa) were present in 10, 3, 26, and 6% of strains. Among them, one eae-γ1–positive O157:H7 strain testing positive for ehxA and astA and two eae-α1–positive O157:H45 strains were classified as enteropathogenic E. coli (EPEC). The O157:H45 EPEC harbored the EAF plasmid and the bfpA gene, factors characteristic for typical EPEC. The isolated STEC strains (43 sorbitol positive) belonged to 11 O:H serotypes, including three previously reported in human STEC causing hemolytic uremic syndrome (O9:H−, O26:H−, and O103:H2). All but one strain harbored stx2e. The eae and ehxA genes, which are strongly correlated with human disease, were present in only one O103:H2 strain positive for stx1 and paa, whereas the astA gene was found more frequently (14 strains). High prevalence of STEC was found among finisher pigs, but according to the virulence factors the majority of these strains seem to be of low virulence.

Risk of Escherichia coli O157:H7, Non-O157 Shiga Toxin–Producing Escherichia coli, and Campylobacter spp. in Food Animals and Their Products in Qatar

2015 ◽  
Vol 78 (10) ◽  
pp. 1812-1818 ◽  
Author(s):  
HUSSNI O. MOHAMMED ◽  
KORANA STIPETIC ◽  
AHMED SALEM ◽  
PATRICK McDONOUGH ◽  
YUNG FU CHANG ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Cross Sectional Study ◽  
Campylobacter Coli ◽  
Escherichia Coli O157 ◽  
Cross Sectional ◽  
Fecal Samples ◽  
E Coli ◽  
Cattle Feces ◽  
Campylobacter Spp

Escherichia coli O157:H7, non-O157 E. coli, and Campylobacter spp. are among the top-ranked pathogens that threaten the safety of food supply systems around the world. The associated risks and predisposing factors were investigated in a dynamic animal population using a repeat-cross-sectional study design. Animal and environmental samples were collected from dairy and camel farms, chicken processing plants, and abattoirs and analyzed for the presence of these pathogens using a combination of bacterial enrichment and real-time PCR tests without culture confirmation. Data on putative risk factors were also collected and analyzed. E. coli O157:H7 was detected by PCR at higher levels in sheep and camel feces than in cattle feces (odds ratios [OR], 6.8 and 21.1, respectively). Although the genes indicating E. coli O157:H7 were detected at a relatively higher rate (4.3%) in fecal samples from dairy cattle, they were less common in milk and udder swabs from the same animals (1 and 2%, respectively). Among the food adulterants, E. coli O103 was more common in cattle fecal samples, whereas O26 was more common in sheep feces and O45 in camel feces compared with cattle (OR, 2.6 and 3.1, respectively). The occurrence of E. coli in the targeted populations differed by the type of sample and season of the year. Campylobacter jejuni and Campylobacter coli were more common in sheep and camel feces than in cattle feces. Most of the survey and surveillance of E. coli focused on serogroup O157 as a potential foodborne hazard; however, based on the PCR results, non-O157 Shiga toxin–producing E. coli serotypes appeared to be more common, and efforts should be made to include them in food safety programs.

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