Novel Single-Tube Agar-Based Test System for Motility Enhancement and Immunocapture of Escherichia coli O157:H7 by H7 Flagellar Antigen-Specific Antibodies

Fecal samples from cattle in 100 feedlots in 13 states were bacteriologically cultured for Escherichia coli O157 that did not ferment sorbitol, lacked beta-glucuronidase, and possessed genes coding for Shiga-like toxin. In each feedlot 30 fresh fecal-pat samples were collected from each of four pens: with the cattle shortest on feed, with cattle longest on feed, and with cattle in two randomly selected pens. E. coli O157 was isolated from 210 (1.8%) of 11,881 fecal samples. One or more samples were positive for E. coli O157 in 63 of the 100 feedlots tested. E. coli O157 was found at roughly equal prevalence in all the geographical regions sampled. The prevalence of E. coli O157 in the pens with cattle shortest on feed was approximately threefold higher than for randomly selected and longest on feed pens. Of the E. coli O157 isolates found in this study, 89.52% expressed the H7 flagellar antigen. E. coli O157 was found to be widely distributed among feedlot cattle, but at a low prevalence, in the United States.

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Serology and Genetics of the Flagellar Antigen of Escherichia coli O157:H7a,7c

Journal of Clinical Microbiology ◽

10.1128/jcm.41.3.1033-1040.2003 ◽

2003 ◽

Vol 41 (3) ◽

pp. 1033-1040 ◽

Cited By ~ 3

Author(s):

Y. A. Ratiner ◽

S. Salmenlinna ◽

M. Eklund ◽

M. Keskimaki ◽

A. Siitonen

Keyword(s):

Escherichia Coli ◽

Escherichia Coli O157 ◽

Flagellar Antigen

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Reverse Transcription-Multiplex PCR Assay for Simultaneous Detection of Escherichia coli O157:H7, Vibrio cholerae O1, and Salmonella Typhi

Clinical Chemistry ◽

10.1373/clinchem.2004.036814 ◽

2004 ◽

Vol 50 (11) ◽

pp. 2037-2044 ◽

Cited By ~ 41

Author(s):

Nicole J Morin ◽

Zhilong Gong ◽

Xing-Fang Li

Keyword(s):

Escherichia Coli ◽

Multiplex Pcr ◽

Vibrio Cholerae ◽

Reverse Transcription ◽

Simultaneous Detection ◽

Salmonella Typhi ◽

Escherichia Coli O157 ◽

Single Tube ◽

E Coli ◽

Vibrio Cholerae O1

Abstract Background: Escherichia coli O157:H7, Vibrio cholerae O1, and Salmonella Typhi are pathogenic bacteria that can be found in contaminated water supplies throughout the world. No currently available assays can simultaneously detect and identify all three pathogens. Our aim was to develop a rapid and reliable technique for simultaneous detection of these pathogens. Methods: Four unique genes were chosen as the targets of detection. Forward and reverse primers were designed to specifically amplify different sizes of these target genes: a 239-bp region of the E. coli O157 lipopolysaccharide (LPS) gene (rfbE); a 179-bp region of the H7 flagellin gene (fliC); a 419-bp region of the V. cholerae O1 LPS gene (rfbE); and a 329-bp region of Salmonella Typhi LPS gene (tyv). To ensure the detection of only viable replicating bacteria, RNA was extracted for analysis. After reverse transcription, cDNAs were simultaneously amplified in a single tube by multiplex PCR. The multiplex PCR products were analyzed by gel electrophoresis. To characterize the assay we analyzed, in a blinded fashion, seven unknown RNA samples containing various combinations of total RNA from these bacteria as well as clinical isolates. Results: All seven unknown RNA samples were correctly identified. The assay was able to detect and identify as few as 30 cells of E. coli O157:H7 and Salmonella Typhi in clinical isolates, and the presence of other bacteria did not interfere with the analysis. Conclusion: An assay combining reverse transcription with single-tube multiplex PCR was successfully developed and validated for simultaneous detection of viable E. coli O157:H7, V. cholerae O1, and Salmonella Typhi.

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Evaluation of the Reveal and SafePath Rapid Escherichia coli O157 Detection Tests for Use on Bovine Feces and Carcasses

Journal of Food Protection ◽

10.4315/0362-028x-63.7.860 ◽

2000 ◽

Vol 63 (7) ◽

pp. 860-866 ◽

Cited By ~ 9

Author(s):

CHRISTINE A. POWER ◽

ROGER P. JOHNSON ◽

SCOTT A. McEWEN ◽

W. BRUCE McNAB ◽

MANSEL W. GRIFFITHS ◽

...

Keyword(s):

Escherichia Coli ◽

Reference System ◽

Reference Method ◽

Field Testing ◽

Immunomagnetic Separation ◽

Test System ◽

Escherichia Coli O157 ◽

E Coli ◽

Beef Carcasses ◽

Bovine Feces

The Reveal (Neogen Corp., Lansing, Mich.) and SafePath (SafePath Laboratories LLC, St. Paul, Minn.) tests were evaluated for their performance as beef fecal and beef carcass Escherichia coli O157:H7 monitoring tests. Agreement between these tests and a reference test system was determined using naturally contaminated bovine feces and beef carcasses. The reference system utilized immunomagnetic separation with plating onto cefixime, tellurite, sorbitol MacConkey agar, followed by colony testing using a serum agglutination test for the O157 antigen. Relative to this reference method, the Reveal test showed a sensitivity of 46% and a specificity of 82% on bovine feces and a specificity of 99% on carcass samples. The SafePath test, demonstrated a significantly higher sensitivity at 79% and a similar specificity of 79%. On carcass samples the SafePath test performed similarly to the Reveal test, demonstrating a specificity of 100% relative to the reference system. There was an insufficient number of E. coli O157-positive carcass samples to estimate precisely the sensitivity of these two methods. Both methods show promise as rapid carcass monitoring tests, but further field testing to estimate sensitivity is needed to complete their evaluation. The proportion of positive fecal samples for E. coli O157:H7 by the reference method ranged from 10.2% to 36% in 10 lots of cattle with an overall mean of 17.3% (39/225). Quarter carcass sponging of 125 carcasses revealed 1.6% positive for the pathogen (2/125).

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H7 antiserum-sorbitol fermentation medium: a single tube screening medium for detecting Escherichia coli O157:H7 associated with hemorrhagic colitis.

Journal of Clinical Microbiology ◽

10.1128/jcm.22.4.620-625.1985 ◽

1985 ◽

Vol 22 (4) ◽

pp. 620-625 ◽

Cited By ~ 94

Author(s):

J J Farmer ◽

B R Davis

Keyword(s):

Escherichia Coli ◽

Fermentation Medium ◽

Hemorrhagic Colitis ◽

Escherichia Coli O157 ◽

Single Tube

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Bedeutung von Escherichia coli O157 beim Schlachtschaf in der Schweiz

Schweizer Archiv für Tierheilkunde ◽

10.1024/0036-7281.148.6.289 ◽

2006 ◽

Vol 148 (6) ◽

pp. 289-295 ◽

Cited By ~ 8

Author(s):

C. Zweifel ◽

M. Kaufmann ◽

J. Blanco ◽

R. Stephan

Keyword(s):

Escherichia Coli ◽

Escherichia Coli O157

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Molecular profiling and antimicrobial susceptibility of Escherichia coli O157:H7 isolated in Bulgaria

BULGARIAN JOURNAL OF VETERINARY MEDICINE ◽

10.15547/bjvm.2263 ◽

2020 ◽

Vol 23 (3) ◽

pp. 310-318

Author(s):

K. Koev ◽

T. Stoyanchev ◽

G. Zhelev ◽

P. Marutsov ◽

K. Gospodinova ◽

...

Keyword(s):

Escherichia Coli ◽

Escherichia Coli O157 ◽

Acid Sensitivity ◽

Lower Extent ◽

Phenotype Analysis ◽

Anal Swab ◽

Amoxicillin Clavulanic Acid ◽

Primary Identification ◽

Stx1 Gene ◽

Cattle Farms

The purpose of this study was to detect the presence of shiga-toxin producing Escherichia coli (STEC) in faeces of healthy dairy cattle and to determine the sensitivity of isolates to several antimicrobial drugs. A total of 1,104 anal swab samples originating from 28 cattle farms were examined. After the primary identification, 30 strains were found to belong to serogroup О157. By means of conventional multiplex PCR, isolates were screened for presence of resistance genes stx1, stx2 and eaeА. Twenty-nine strains possesses amplicons with a size corresponding to genes stx2 and eaeA, one had amplicons also for the stx1 gene and one lacked amplicons of all three genes. Twenty-eight strains demonstrated amplicons equivalent to gene H7. The results from phenotype analysis of resistance showed preserved sensitivity to ceftriaxone, ceftazidime, cefotaxime, cephalothin, streptomycin, gentamicin, tetracycline, enrofloxacin and combinations sulfamethoxazole/trimethoprim and amoxicillin/clavulanic acid. Sensitivity to ampicillin was relatively preserved, although at a lower extent.

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