Escherichia coli O157:H7 Populations in Sheep Can Be Reduced by Chlorate Supplementation†

2003 ◽  
Vol 66 (2) ◽  
pp. 194-199 ◽  
Author(s):  
T. R. CALLAWAY ◽  
T. S. EDRINGTON ◽  
R. C. ANDERSON ◽  
K. J. GENOVESE ◽  
T. L. POOLE ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Nitrate Reductase ◽  
Foodborne Pathogens ◽  
Intestinal Tract ◽  
Foodborne Pathogen ◽  
Escherichia Coli O157 ◽  
Foodborne Illnesses ◽  
Fatty Acid Production ◽  
E Coli ◽  
Ruminant Animals

Ruminant animals are a natural reservoir of the foodborne pathogen Escherichia coli O157:H7. Some foodborne pathogens (e.g., E. coli) are equipped with a nitrate reductase that cometabolically reduces chlorate. The intracellular reduction of chlorate to chlorite kills nitrate reductase–positive bacteria; however, species that do not reduce nitrate are not affected by chlorate. Therefore, it has been suggested that ruminants be supplemented with chlorate prior to shipment for slaughter in order to reduce foodborne illnesses in human consumers. Sheep (n = 14) were fed a high-grain ration and were experimentally infected with E. coli O157:H7. These sheep were given an experimental product (XCP) containing the equivalent of either 2.5 mM NaNO3 and 100 mM NaCl (control sheep; n = 7) or 2.5 mM NaNO3 and 100 mM NaClO3 (chlorate [XCP]–treated sheep; n = 7). Control and XCP-treated sheep were treated for 24 h; XCP treatment reduced the population of inoculated E. coli O157:H7 (P < 0.05) from 102, 105, and 105 CFU/g in the rumen, cecum, and rectum, respectively, to <101 CFU/g in all three sections of the gastrointestinal tract. The number of sheep testing positive for E. coli O157:H7 was significantly reduced by XCP treatment. In a similar fashion, total E. coli and coliforms were also reduced (P < 0.05) in all three compartments of the intestinal tract. Intestinal pH, total volatile fatty acid production, and the acetate/propionate ratio were unaffected by XCP treatment. On the basis of these results, it appears that chlorate treatment can be an effective method for the reduction of E. coli O157:H7 populations in ruminant animals immediately prior to slaughter.

Incidence and Toxin Production Ability of Escherichia coli O157:H7 Isolated from Cattle Trucks†

2007 ◽  
Vol 70 (10) ◽  
pp. 2383-2385 ◽  
Author(s):  
E. P. CUESTA ALONSO ◽  
S. E. GILLILAND ◽  
C. R. KREHBIEL
Keyword(s):  
Escherichia Coli ◽  
Potential Risk ◽  
Foodborne Pathogen ◽  
Toxin Production ◽  
Escherichia Coli O157 ◽  
Foodborne Illnesses ◽  
E Coli

Twelve cattle trucks were analyzed for the presence of Escherichia coli O157:H7. Three of them had been washed prior to arrival, and the others had not. Seventy-five percent of the trailers were positive for the presence of this foodborne pathogen. A total of 54 cultures were isolated and identified as E. coli O157:H7, all from the trucks that had not been cleaned. Most of the cultures (96.4%) produced Shiga-like toxin (verotoxin). No E. coli O157:H7 was detected in cattle trucks that were cleaned before arrival at the cattle pens. The incidence of E. coli O157:H7 in transport trailers increases the potential risk of contamination of cattle and transmission from farms to feedlots and to packing plants. This contamination increases the potential of contamination of meat during harvest and the risk of foodborne illnesses.

An Aggregation-Induced Emission Material Labeling Antigen-Based Lateral Flow Immunoassay Strip for Rapid Detection of Escherichia coli O157:H7

2021 ◽  
pp. 247263032098193
Author(s):  
Cheng Liu ◽  
Shuiqin Fang ◽  
Yachen Tian ◽  
Youxue Wu ◽  
Meijiao Wu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Rapid Detection ◽  
Foodborne Pathogen ◽  
Test Strip ◽  
Lateral Flow ◽  
Detection Sensitivity ◽  
Lateral Flow Immunoassay ◽  
Escherichia Coli O157 ◽  
Aggregation Induced Emission ◽  
E Coli

Escherichia coli O157:H7 ( E. coli O157:H7) is a dangerous foodborne pathogen, mainly found in beef, milk, fruits, and their products, causing harm to human health or even death. Therefore, the detection of E. coli O157:H7 in food is particularly important. In this paper, we report a lateral flow immunoassay strip (LFIS) based on aggregation-induced emission (AIE) material labeling antigen as a fluorescent probe for the rapid detection of E. coli O157:H7. The detection sensitivity of the strip is 105 CFU/mL, which is 10 times higher than that of the colloidal gold test strip. This method has good specificity and stability and can be used to detect about 250 CFU of E. coli O157:H7 successfully in 25 g or 25 mL of beef, jelly, and milk. AIE-LFIS might be valuable in monitoring food pathogens for rapid detection.

Ability ofEscherichia coliO157:H7 isolates to colonize the intestinal tract of conventional adult CD1 mice is transient

2001 ◽  
Vol 47 (1) ◽  
pp. 91-95 ◽  
Author(s):  
J Wayne Conlan ◽  
Sonia L Bardy ◽  
Rhonda KuoLee ◽  
Ann Webb ◽  
Malcolm B Perry
Keyword(s):  
Escherichia Coli ◽  
Mouse Model ◽  
Intestinal Tract ◽  
Vaccine Development ◽  
Escherichia Coli O157 ◽  
Intestinal Colonization ◽  
E Coli ◽  
Cd1 Mice ◽  
A Current

In an attempt to improve upon a current mouse model of intestinal colonization by Escherichia coli O157:H7 used in this laboratory for vaccine development, nine clinical isolates of the pathogen were screened for their ability to persist in the intestinal tract of conventional adult CD-1 mice. None of the test isolates of E. coli O157:H7 were capable of colonizing these mice for a period of more than two weeks. Most of the isolates appeared to be benign for the experimental host, but one isolate was lethal. This virulence correlated with the ability of the latter isolate to produce large quantities of Shiga-like toxin 2 in vitro.

A Comparison of the Survival in Feces and Water of Escherichia coli O157:H7 Grown under Laboratory Conditions or Obtained from Cattle Feces

2006 ◽  
Vol 69 (1) ◽  
pp. 6-11 ◽  
Author(s):  
L. SCOTT ◽  
P. McGEE ◽  
J. J. SHERIDAN ◽  
B. EARLEY ◽  
N. LEONARD
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogen ◽  
Hemorrhagic Colitis ◽  
Contaminated Water ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Cattle Feces ◽  
Oral Inoculation ◽  
Before And After ◽  
Uremic Syndrome

Escherichia coli O157:H7 is an important foodborne pathogen that can cause hemorrhagic colitis and hemolytic uremic syndrome. Cattle feces and fecally contaminated water are important in the transmission of this organism on the farm. In this study, the survival of E. coli O157:H7 in feces and water was compared following passage through the animal digestive tract or preparation in the laboratory. Feces were collected from steers before and after oral inoculation with a marked strain of E. coli O157:H7. Fecal samples collected before cattle inoculation were subsequently inoculated with the marked strain of E. coli O157:H7 prepared in the laboratory. Subsamples were taken from both animal and laboratory-inoculated feces to inoculate 5-liter volumes of water. E. coli O157:H7 in feces survived up to 97 days, and survival was not affected by the method used to prepare the inoculating strain. E. coli O157:H7 survived up to 109 days in water, and the bacteria collected from inoculated cattle were detected up to 10 weeks longer than the laboratory-prepared culture. This study suggests that pathogen survival in low-nutrient conditions may be enhanced by passage through the gastrointestinal tract.

scholarly journals Growth of Salmonella and Other Foodborne Pathogens on Inoculated Inshell Pistachios during Simulated Delays between Hulling and Drying

2019 ◽  
Vol 82 (5) ◽  
pp. 815-825 ◽  
Author(s):  
MAHTA MOUSSAVI ◽  
VANESSA LIEBERMAN ◽  
CHRIS THEOFEL ◽  
JAVAD BAROUEI ◽  
LINDA J. HARRIS
Keyword(s):  
Escherichia Coli ◽  
Relative Humidity ◽  
Foodborne Pathogens ◽  
Lag Time ◽  
Escherichia Coli O157 ◽  
Contributing Factors ◽  
Shell Surface ◽  
E Coli ◽  
Significant Growth ◽  
Lower Maximum

ABSTRACT During harvest, pistachios are hulled, separated in water into floater and sinker streams (in large part on the basis of nut density), and then dried before storage. Higher prevalence and levels of Salmonella were previously observed in floater pistachios, but contributing factors are unclear. To examine the behavior of pathogens on hulled pistachios during simulated drying delays, floater and sinker pistachios collected from commercial processors were inoculated at 1 or 3 log CFU/g with cocktails of Salmonella and in some cases Escherichia coli O157:H7 or Listeria monocytogenes and incubated for up to 30 h at 37°C and 90% relative humidity. Populations were measured by plating onto tryptic soy agar and appropriate selective agars. In most cases, no significant growth (P > 0.05) of Salmonella was observed in the first 3 h after inoculation in hulled floaters and sinkers. Growth of Salmonella was greater on floater pistachios than on corresponding sinkers and on floater pistachios with ≥25% hull adhering to the shell surface than on corresponding floaters with <25% adhering hull. Maximum Salmonella populations (2 to 7 log CFU/g) were ∼2-log higher on floaters than on corresponding sinkers. The growth of E. coli O157:H7 and Salmonella on hulled pistachios was similar, but a longer lag time (approximately 11 h) and significantly lower maximum populations (4 versus 5 to 6 log CFU/g; P < 0.05) were predicted for L. monocytogenes. Significant growth of pathogens on hulled pistachios is possible when delays between hulling and drying are longer than 3 h, and pathogen growth is enhanced in the presence of adhering hull material.

Rapid and accurate detection of Escherichia coli O157:H7 in beef using microfluidic wax-printed paper-based ELISA

The Analyst ◽  
2020 ◽  
Vol 145 (8) ◽  
pp. 3106-3115 ◽  
Author(s):  
Yanan Zhao ◽  
Dexin Zeng ◽  
Chao Yan ◽  
Wei Chen ◽  
Jianluan Ren ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Point Of Care ◽  
Foodborne Pathogen ◽  
Escherichia Coli O157 ◽  
Good Sensitivity ◽  
Point Of Care Testing ◽  
Accurate Detection ◽  
New Ideas ◽  
Sensitivity Specificity

Escherichia coli O157:H7 is a severe foodborne pathogen. Paper-based ELISA can rapidly and accurately detect E.coli O157:H7 in beef. The method has good sensitivity, specificity and repeatability. It is suitable for point-of-care testing and offers new ideas for the detection of other foodborne pathogens.

Inactivation of Escherichia coli O157:H7 and Salmonella and Native Microbiota on Fresh Strawberries by Antimicrobial Washing and Coating

2018 ◽  
Vol 81 (8) ◽  
pp. 1227-1235 ◽  
Author(s):  
MINGMING GUO ◽  
TONY Z. JIN ◽  
JOSHUA B. GURTLER ◽  
XUETONG FAN ◽  
MADHAV P. YADAV
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Allyl Isothiocyanate ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Native Microflora ◽  
Pathogen Populations ◽  
Antimicrobial Treatments ◽  
Antimicrobial Effectiveness

ABSTRACT Antimicrobial washing (AW), antimicrobial coating (AC), and a combination of washing followed by coating (AW+AC) were evaluated for their ability to inactivate artificially inoculated foodborne pathogens and native microbiota on strawberries stored at 4°C. Strawberries were inoculated with a six-strain composite of Escherichia coli O157:H7 and Salmonella; treated by AW, AC, or AW+AC; and stored at 4°C for 3 weeks. The washing solution contained 90 ppm of peracetic acid, and the coating solution consisted of chitosan (1%, w/v), allyl isothiocyanate (1%, v/v), and corn-bio fiber gum (5%, w/v). The effectiveness of the antimicrobial treatments against E. coli O157:H7 and Salmonella pathogens and native microflora on strawberries and their impact on fruit quality (appearance, weight loss, color, and firmness) were determined. By the end of storage, pathogen populations on strawberries were 2.5 (AW+AC), 2.9 (AC), 3.8 (AW), and 4.2 log CFU for the positive (untreated) control. AW+AC treatments also inactivated the greatest population of native microflora, followed by the AC treatment alone. AW+AC treatments showed additional antimicrobial effectiveness against these two pathogens and native microflora. Both AW+AC and AC treatments preserved the color, texture, and appearance of strawberries throughout storage. The coating treatments (AW+AC and AC alone) further reduced the loss of moisture throughout storage. The AW treatment was the least effective in reducing populations of pathogens and native microflora and in maintaining the quality of strawberries throughout storage. This study demonstrates a method to improve the microbiological safety, shelf life, and quality of strawberries.

Rapid and Sensitive Detection of Escherichia coli O157:H7 in Milk and Ground Beef Using Magnetic Bead–Based Immunoassay Coupled with Tyramide Signal Amplification

2014 ◽  
Vol 77 (1) ◽  
pp. 100-105 ◽  
Author(s):  
MUHSIN AYDIN ◽  
GENE P. D. HERZIG ◽  
KWANG CHEOL JEONG ◽  
SAMANTHA DUNIGAN ◽  
PARTH SHAH ◽  
...  
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Food Safety ◽  
Foodborne Pathogens ◽  
Signal Amplification ◽  
Magnetic Bead ◽  
Escherichia Coli O157 ◽  
Tyramide Signal Amplification ◽  
E Coli ◽  
Enrichment Step

Escherichia coli O157:H7 is a major foodborne pathogen that has posed serious problems for food safety and public health. Recent outbreaks and recalls associated with various foods contaminated by E. coli O157:H7 clearly indicate its deleterious effect on food safety. A rapid and sensitive detection assay is needed for this harmful organism to prevent foodborne illnesses and control outbreaks in a timely manner. We developed a magnetic bead–based immunoassay for detection of E. coli O157:H7 (the most well-known Shiga toxigenic E. coli strain) with a 96-well microplate as an assay platform. Immunomagnetic separation (IMS) and tyramide signal amplification were coupled to the assay to increase its sensitivity and specificity. This immunoassay was able to detect E. coli O157:H7 in pure culture with a detection limit of 50 CFU/ml in less than 3 h without an enrichment step. The detection limit was decreased 10-fold to 5 CFU/ml with addition of a 3-h enrichment step. When this assay was tested with other nontarget foodborne pathogens and common enteric bacteria, no cross-reactivity was found. When tested with artificially contaminated ground beef and milk samples, the assay sensitivity decreased two- to fivefold, with detection limits of 250 and 100 CFU/ml, respectively, probably because of the food matrix effect. The assay results also were compared with those of a sandwich-type enzyme-linked immunosorbent assay (ELISA) and an ELISA coupled with IMS; the developed assay was 25 times and 4 times more sensitive than the standard ELISA and the IMS-ELISA, respectively. Tyramide signal amplification combined with IMS can improve sensitivity and specificity for detection of E. coli O157:H7. The developed assay could be easily adapted for other foodborne pathogens and will contribute to improved food safety and public health.

Inactivation of Escherichia coli O157:H7 and Listeria monocytogenes on Plastic Kitchen Cutting Boards by Electrolyzed Oxidizing Water

1999 ◽  
Vol 62 (8) ◽  
pp. 857-860 ◽  
Author(s):  
KUMAR S. VENKITANARAYANAN ◽  
GABRIEL O. I. EZEIKE ◽  
YEN-CON HUNG ◽  
MICHAEL P. DOYLE
Keyword(s):  
Escherichia Coli ◽  
Listeria Monocytogenes ◽  
Laminar Flow ◽  
Foodborne Pathogens ◽  
Deionized Water ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Laminar Flow Hood ◽  
Cutting Boards ◽  
Temperature Time

One milliliter of culture containing a five-strain mixture of Escherichia coli O157:H7 (∼1010 CFU) was inoculated on a 100-cm2 area marked on unscarred cutting boards. Following inoculation, the boards were air-dried under a laminar flow hood for 1 h, immersed in 2 liters of electrolyzed oxidizing water or sterile deionized water at 23°C or 35°C for 10 or 20 min; 45°C for 5 or 10 min; or 55°C for 5 min. After each temperature–time combination, the surviving population of the pathogen on cutting boards and in soaking water was determined. Soaking of inoculated cutting boards in electrolyzed oxidizing water reduced E. coli O157:H7 populations by ≥5.0 log CFU/100 cm2 on cutting boards. However, immersion of cutting boards in deionized water decreased the pathogen count only by 1.0 to 1.5 log CFU/100 cm2. Treatment of cutting boards inoculated with Listeria monocytogenes in electrolyzed oxidizing water at selected temperature–time combinations (23°C for 20 min, 35°C for 10 min, and 45°C for 10 min) substantially reduced the populations of L. monocytogenes in comparison to the counts recovered from the boards immersed in deionized water. E. coli O157:H7 and L. monocytogenes were not detected in electrolyzed oxidizing water after soaking treatment, whereas the pathogens survived in the deionized water used for soaking the cutting boards. This study revealed that immersion of kitchen cutting boards in electrolyzed oxidizing water could be used as an effective method for inactivating foodborne pathogens on smooth, plastic cutting boards.

Parenteral immunization with a glycoconjugate vaccine containing the O157 antigen of Escherichia coli O157:H7 elicits a systemic humoral immune response in mice, but fails to prevent colonization by the pathogen

1999 ◽  
Vol 45 (4) ◽  
pp. 279-286
Author(s):  
J Wayne Conlan ◽  
Andrew D Cox ◽  
Rhonda KuoLee ◽  
Ann Webb ◽  
Malcolm B Perry
Keyword(s):  
Escherichia Coli ◽  
Intestinal Tract ◽  
Horse Serum ◽  
Convincing Evidence ◽  
Escherichia Coli O157 ◽  
Intestinal Colonization ◽  
E Coli ◽  
Humoral Immune ◽  
Parenteral Immunization ◽  
Glycoconjugate Vaccine

The results of the present study show that whereas both BALB/c and C57BL/6 mice parenterally inoculated with a horse serum albumin - Escherichia coli O157 antigen conjugate vaccine develop systemic, specific antibodies to the carrier protein, only the former mice routinely develop antibodies to the carbohydrate O157 moiety. However, little convincing evidence was found to show that these antibodies transuded into the intestinal tract either naturally or in response to an oral inoculum of the pathogen. Moreover, this vaccination procedure failed to protect mice against intestinal colonization following oral challenge with the pathogen. Thus, the results of this study suggest that parenteral vaccination might be an unsuitable strategy for combatting E. coli O157:H7 organisms located in the gut.Key words: Escherichia coli, glycoconjugate vaccine, mice.

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