scholarly journals Evaluation of stx1, stx2, hlyA, and eaeA Virulence Genes in Escherichia coli O157:H7 Isolated from Meat (Beef and Mutton) in Hamedan, Iran, During 2015-2016

2020 ◽  
Vol 8 (2) ◽  
pp. 55-59
Author(s):  
Fatemeh Binandeh ◽  
Mohammadreza Pajohi-Alamoti ◽  
Pezhman Mahmoodi ◽  
Azam Ahangari
Keyword(s):  
Escherichia Coli ◽  
Virulence Genes ◽  
Escherichia Coli O157 ◽  
Isolation And Identification ◽  
E Coli ◽  
Multiplex Pcr Assay ◽  
Agar Media ◽  
Cattle Meat ◽  
Meat Samples ◽  
Encoding Genes

Background and Objectives: Consuming raw or undercooked cattle meat is the most common transmission way of infection with Escherichia coli O157:H7. The present study aimed to identify virulence genes stx1, stx2, hlyA, and eaeA in E. coli isolated from meat samples (beef and mutton) in Hamedan during 2015 and 2016. Materials and Methods: For this purpose, the swabs were randomly taken from 160 meat samples including 80 beef samples and 80 mutton samples from butcher shops. Isolation and identification of E. coli cells were conducted by culturing the swab samples on MacConkey agar and Eosin methylene blue agar media. Then, the identity of the suspected E. coli O157:H7 colonies was investigated by a multiplex PCR assay and eventually, the isolates were evaluated for the presence of stx1, stx2, hlyA, eaeA virulence genes. Results: The results showed that out of 160 cultured samples on the selective media, 60 samples (37.5%) were contaminated with E. coli. O157:H7, O157, and H7 strains were identified using PCR, among which only E. coli O157:H7 possessed all four virulence factor encoding genes. Conclusion: The results of this study showed that beef could be a reservoir for E. coli O157:H7, and it may be involved in the transmission of this pathogen to humans.

Comparison of Methods for Detection and Isolation of Cold- and Freeze-Stressed Escherichia coli O157:H7 in Raw Ground Beef†

2007 ◽  
Vol 70 (7) ◽  
pp. 1663-1669 ◽  
Author(s):  
PINA M. FRATAMICO ◽  
LORI K. BAGI
Keyword(s):  
Escherichia Coli ◽  
Ground Beef ◽  
Escherichia Coli O157 ◽  
Pcr Assay ◽  
Initial Inoculum ◽  
E Coli ◽  
Multiplex Pcr Assay ◽  
Treatment Type ◽  
Agar Media ◽  
Main Effects

A comparison was made of the relative efficiencies of three enrichment media, RapidChek Escherichia coli O157:H7 enrichment broth (REB), R&F broth (RFB), and modified E. coli broth containing novobiocin (mEC+n), and four selective plating media for detection of cold- and freeze-stressed E. coli O157:H7 in raw ground beef. Ground beef (25 g) was inoculated with E. coli O157:H7 at ≤0.5 and ≤2 CFU/g, and samples were then enriched immediately or were stored at 4°C for 72 h or at −20°C for 2 weeks and then enriched. After 8 or 20 h of enrichment, the cultures were plated onto R&F E. coli O157: H7 chromogenic plating medium, cefixime-tellurite sorbitol MacConkey agar, CHROMagar O157, and Rainbow agar O157 and tested using the RapidChek E. coli O157 lateral flow immunoassay and a multiplex PCR assay targeting the E. coli O157: H7 eae, stx1, and stx2 genes. Recovery of E. coli O157:H7 on the four agar media was 4.0 to 7.9 log CFU/ml with the REB enrichment, 1.4 to 7.4 log CFU/ml with RFB, 1.7 to 6.7 log CFU/ml with mEC+n incubated at 42°C, and 1.3 to 3.3 log CFU/ml from mEC+n incubated at 35°C. The percentages of positive ground beef samples containing nonstressed, cold-stressed, and freeze-stressed E. coli O157:H7 as obtained by plating, the immunoassay, and the PCR assay were 97, 88, and 97%, respectively, with REB, 92, 81, and 78%, respectively, with RFB, 97, 58, and 53%, respectively, with mEC+n incubated at 42°C, and 22, 31, and 25%, respectively, with mEC+n incubated at 35°C. Logistic regression analyses of the data indicated significant main effects of treatment, type of medium, enrichment time, inoculum concentration, and detection method. In particular, a positive result was 1.1 times more likely to occur after 20 h of enrichment than after 8 h, 25 times more likely with RFB and REB than with mEC+nat35°C, 3.7 times more likely with an initial inoculum of ≤2.0 CFU/g than with ≤0.5 CFU/g, 2.5 to 3 times more likely using freeze-stressed or nonstressed bacteria than with cold-stressed bacteria, and 2.5 times more likely by plating than by the immunoassay or the PCR assay. REB had better overall performance for enrichment of cold- and freeze-stressed E. coli O157:H7 present in ground beef than did the other media examined.

scholarly journals Effect of Electron Beam Irradiation on Survival of Escherichia coli O157:H7 and Salmonella enterica serovar Thyphimurium in Minced Camel Meat during Refrigerated Storage

2019 ◽  
Author(s):  
A. Amiri ◽  
H. Zandi ◽  
H. Mozaffari Khosravi
Keyword(s):  
Escherichia Coli ◽  
Electron Beam ◽  
Electron Beam Irradiation ◽  
Escherichia Coli O157 ◽  
Refrigerated Storage ◽  
Beam Irradiation ◽  
E Coli ◽  
Serovar Typhimurium ◽  
Camel Meat ◽  
Meat Samples

Background: Electron beam irradiation is one of the effective ways to control foodborne pathogens. We evaluated the effect of electron beam irradiation on survival of Escherichia coli O157:H7 and Salmonella enterica serovar Thyphimurium in minced camel meat during refrigerated storage. Methods: The meat samples were inoculated with E. coli O157:H7 and S. enterica serovar Thyphimurium and then irradiated with doses of 0, 1, 2, 3, and 5 kGy. The samples were stored at 4±1 °C and evaluated microbiologically up to 10 days. Data were analyzed using SPSS software version 18. Results: The microbial loads of minced camel meat samples were significantly reduced (p<0.0001) with increasing the dose of irradiation. The most effective dose was 5 kGy that highly reduced S. enterica serovar Typhimurium, and completely destroyed E. coli O157:H7. However, E. coli O157:H7 was more sensitive to electron beam irradiation than S. enterica serovar Typhimurium. Conclusion: Electron beam irradiation effectively reduced the population of both E. coli O157:H7 and S. enterica serovar Typhimurium in minced camel meat in a dose dependent manner.

Prevalence of shiga toxin-producing Escherichia coli O157, O26 and O111 in milk, meat and faeces of cattle, sheep and pigs slaughtered in Benin

2020 ◽  
Vol 152 ◽  
pp. 15667-15675
Author(s):  
Chakirath Folakè Arikè Salifou ◽  
Cyrille Boko ◽  
Isidore Houaga ◽  
Raoul Agossa ◽  
Isabelle Ogbankotan ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Virulence Genes ◽  
Animal Origin ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Milk Samples ◽  
Food Of Animal Origin ◽  
Cattle Faeces ◽  
Risk Assessment And Management

Objectives: The study aimed to search for E. coli O157 and non-O157 in milk, meat and faeces of cattle, sheep and pigs slaughtered in Cotonou. Methodology and Results: One hundred and Seventy-Five (175) samples including 25 meat, 25 faeces per species and 25 milk from cattle were analysed for E. coli O157; O26 and O111 and the virulence genes were identified by PCR. The SAS software (1998) and the bilateral Z test were used to calculate and compare the identification frequencies. E. coli O157 was identified in 4% of cattle faeces, 4% of sheep faeces, and 20% of beef and, in 20% of milk samples. E. coli O26 was identified in 12% of cattle faeces and, in 8% of beef samples. E. coli O111 was identified at frequencies of 8%, and 12% in faeces of sheep and pigs, respectively. The eae gene was detected in 4% of beef, ovine meat, milk, pig faeces and in sheep faeces. stx1 was detected in 8% of milk, and in 4% of bovine and sheep faeces. The strains possessing the gene were all of E. coli O157 with the exception of one from pig faeces identified as O111. Conclusions and application of findings: The presence of these serogroups of E. coli with virulence genes poses a real food safety problem in Benin. This study findings must be taken into account for risk assessment and management related to the consumption of food of animal origin. Keywords: Benin, E. coli O157, O26, O111, faeces, meat, milk

scholarly journals Antimicrobial Resistance Pattern of Escherichia coli Isolated from Frozen Chicken Meat in Bangladesh

Pathogens ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 420 ◽  
Author(s):  
Mst. Sonia Parvin ◽  
Sudipta Talukder ◽  
Md. Yamin Ali ◽  
Emdadul Haque Chowdhury ◽  
Md. Tanvir Rahman ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Foodborne Pathogens ◽  
Biochemical Properties ◽  
Chicken Meat ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Isolation And Identification ◽  
E Coli ◽  
Encoding Genes

Escherichia coli is known as one of the most important foodborne pathogens in humans, and contaminated chicken meat is an important source of foodborne infection with this bacterium. The occurrence of extended-spectrum β-lactamase (ESBL)-producing E. coli (ESBL-Ec), in particular, in chicken meat is considered a global health problem. This study aimed to determine the magnitude of E. coli, with special emphasis on ESBL-Ec, along with their phenotypic antimicrobial resistance pattern in frozen chicken meat. The study also focused on the determination of ESBL-encoding genes in E. coli. A total of 113 frozen chicken meat samples were purchased from 40 outlets of nine branded supershops in five megacities in Bangladesh. Isolation and identification of E. coli were done based on cultural and biochemical properties, as well as PCR assay. The resistance pattern was determined by the disc diffusion method. ESBL-encoding genes were determined by multiplex PCR. The results showed that 76.1% of samples were positive for E. coli, of which 86% were ESBL producers. All the isolates were multidrug-resistant (MDR). Resistance to 9–11 and 12–13 antimicrobial classes was observed in 38.4% and 17.4% isolates, respectively, while only 11.6% were resistant to 3–5 classes. Possible extensive drug resistance (pXDR) was found in 2.3% of isolates. High single resistance was observed for oxytetracycline (93%) and amoxicillin (91.9%), followed by ampicillin (89.5%), trimethoprim–sulfamethoxazole, and pefloxacin (88.4%), and tetracycline (84.9%). Most importantly, 89.6% of isolates were resistant to carbapenems. All the isolates were positive for the blaTEM gene. However, the blaSHV and blaCTX-M-2 genes were identified in two ESBL-non producer isolates. None of the isolates carried the blaCTX-M-1 gene. This study provided evidence of the existence of MDR and pXDR ESBL-Ec in frozen chicken meat in Bangladesh, which may pose a risk to human health if the meat is not properly cooked or pickled raw only. This emphasizes the importance of the implementation of good slaughtering and processing practices by the processors.

Occurrence and Characterization of Escherichia coli O157 and Other Serotypes in Raw Meat Products in Morocco

2008 ◽  
Vol 71 (10) ◽  
pp. 2082-2086 ◽  
Author(s):  
LUCIANO BENEDUCE ◽  
GIUSEPPE SPANO ◽  
ARI Q. NABI ◽  
FRANCESCO LAMACCHIA ◽  
SALVATORE MASSA ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Susceptibility Testing ◽  
Meat Products ◽  
Molecular Techniques ◽  
Escherichia Coli O157 ◽  
Raw Meat ◽  
E Coli ◽  
Meat Samples ◽  
The City

In this study, 100 raw meat samples were collected from 15 local Moroccan butcheries in five different areas of the city of Rabat during a period of 4 months. Overall, 7 of 15 butcheries from three areas of the city yielded strains of Escherichia coli O157. Single isolates from 9 (9%) of 100 raw meat samples were biochemically and serologically confirmed as E. coli O157. Using molecular techniques, two strains were positive for the Shiga toxin, with two additional strains containing an attaching-effacing gene. All potentially virulent serotypes isolated from these meat samples showed distinct pulsed-field gel electrophoresis profiles. Based on antibiotic susceptibility testing, more than 70% of the isolates were resistant to ampicillin and clavulanic acid–amoxicillin. Moreover, one strain was resistant to more than three antibiotics. Our study represents the first survey of E. coli O157 and related serotypes in raw meat products in Morocco.

scholarly journals Detex for Detection of Escherichia coli O157 in Raw Ground Beef and Raw Ground Poultry

2001 ◽  
Vol 84 (3) ◽  
pp. 752-760 ◽  
Author(s):  
Yvette M Henry ◽  
Nandini Natrajan ◽  
Wendy F Lauer
Keyword(s):  
Escherichia Coli ◽  
False Positive Rate ◽  
Ground Beef ◽  
Escherichia Coli O157 ◽  
Department Of Agriculture ◽  
E Coli ◽  
Metal Plating ◽  
Positive Rate ◽  
Meat Samples ◽  
Inspection Service

Abstract A method for detection of Escherichia coli O157 in beef and poultry is presented. The method is antibody-based and uses a patented antibody-specific metal-plating procedure for the detection of E. coli O157 in enriched meat samples. Both raw ground beef and raw ground poultry were tested as matrixes for the organism. The sensitivity and specificity of the assay were 98 and 90%, respectively. The accuracy of the assay was 96%. Overall, the method agreement between the E. coli O157 Detex assay and the U.S. Department of Agriculture/Food Safety Inspection Service method was 96%. Sample temperature upon loading of the apparatus was critical to the observed false-positive rate of the system.

Ascorbic Acid Enhances Destruction of Escherichia coli O157:H7 during Home-Type Drying of Apple Slices

2001 ◽  
Vol 64 (8) ◽  
pp. 1244-1248 ◽  
Author(s):  
JENNIFER A. BURNHAM ◽  
PATRICIA A. KENDALL ◽  
JOHN N. SOFOS
Keyword(s):  
Escherichia Coli ◽  
Ascorbic Acid ◽  
Acid Solution ◽  
Escherichia Coli O157 ◽  
Bacterial Populations ◽  
Ascorbic Acid Solution ◽  
Initial Inoculum ◽  
E Coli ◽  
Apple Slices ◽  
Agar Media

Destruction of Escherichia coli O157:H7 was evaluated on inoculated apple slices dehydrated at two temperatures with and without application of predrying treatments. Half-ring slices (0.6 cm thick) of peeled and cored Gala apples were inoculated by immersion for 30 min in a four-strain composite inoculum of E. coli O157:H7. The inoculated slices (8.7 to 9.4 log CFU/g) either received no predrying treatment (control), were soaked for 15 min in a 3.4% ascorbic acid solution, or were steam blanched for 3 min at 88°C immediately prior to drying at 57.2 or 62.8°C for up to 6 h. Samples were plated on tryptic soy (TSA) and sorbitol MacConkey (SMAC) agar media for direct enumeration of surviving bacterial populations. Steam blanching changed initial inoculation levels by +0.3 to −0.7 log CFU/g, while immersion in the ascorbic acid solution reduced the inoculation levels by 1.4 to 1.6 log CFU/g. Dehydration of control samples for 6 h reduced mean bacterial populations by 2.9 log CFU/g (TSA or SMAC) at 57.2°C and by 3.3 (SMAC) and 3.5 (TSA) log CFU/g at 62.8°C. Mean decreases from initial inoculum levels for steam-blanched slices after 6 h of drying were 2.1 (SMAC) and 2.0 (TSA) log CFU/g at 57.2°C, and 3.6 (TSA or SMAC) log CFU/g at 62.8°C. In contrast, initial bacterial populations on ascorbic acid–pretreated apple slices declined by 5.0 (SMAC) and 5.1 (TSA) log CFU/g after 3 h of dehydration at 57.2°C, and by 7.3 (SMAC) and 6.9 (TSA) log CFU/g after 3 h at 62.8°C. Reductions on slices treated with ascorbic acid were in the range of 8.0 to 8.3 log CFU/g after 6 h of drying, irrespective of drying temperature or agar medium used. The results of immersing apple slices in a 3.4% ascorbic acid solution for 15 min prior to drying indicate that a predrying treatment enhances the destruction of E. coli O157:H7 on home-dried apple products.

Virulence Characterization and Molecular Subtyping of Typical and Atypical Escherichia coli O157:H7 and O157:H(−) Isolated from Fecal Samples and Beef Carcasses in Mexico

2015 ◽  
Vol 78 (2) ◽  
pp. 264-272 ◽  
Author(s):  
CLAUDIA NARVÁEZ-BRAVO ◽  
ALEJANDRO ECHEVERRY ◽  
MARKUS F. MILLER ◽  
ARGENIS RODAS-GONZÁLEZ ◽  
M. TODD BRASHEARS ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Genes ◽  
Immunomagnetic Separation ◽  
Latex Agglutination ◽  
Escherichia Coli O157 ◽  
High Genetic Diversity ◽  
E Coli ◽  
System A ◽  
Metabolic Genes ◽  
Beef Carcasses

The objective of the study was to characterize virulence genes and subtype Escherichia coli O157:H7 and O157:H(−) isolates obtained from a vertically integrated feedlot slaughter plant in Mexico. A total of 1,695 samples were collected from feedlots, holding pens, colon contents, hides, and carcasses. E. coli O157:H7 detection and confirmation was carried out using conventional microbiology techniques, immunomagnetic separation, latex agglutination, and the BAX system. A total of 97 E. coli O157 strains were recovered and screened for key virulence and metabolic genes using multiplex and conventional PCR. Eighty-eight (91.72%) of the strains carried stx2, eae, and ehxA genes. Ten isolates (8.25%) were atypical sorbitol-fermenting strains, and nine were negative for the flicH7 gene and lacked eae, stx1, stx2, and ehxA. One sorbitol-positive strain carried stx2, eae, tir, toxB, and iha genes but was negative for stx1 and ehxA. Pulsed-field gel electrophoresis (PFGE) analysis yielded 49 different PFGE subtypes, showing a high genetic diversity; however, the majority of the typical isolates were closely related (80 to 90% cutoff). Atypical O157 isolates were not closely related within them or to typical E. coli O157:H7 isolates. Identical PFGE subtypes were found in samples obtained from colon contents, feedlots, holding pens, and carcasses. Isolation of a sorbitol-fermenting E. coli O157 positive for a number of virulence genes is a novel finding in Mexico. These data showed that genetically similar strains of E. coli O157:H7 can be found at various stages of beef production and highlights the importance of preventing cross-contamination at the pre- and postharvest stages of processing.

scholarly journals Isolation and Identification of Salmonella and Escherichia coli from Raw Goat Meat in Uyo Metropolis, Akwaibom State

2020 ◽  
pp. 50-60
Author(s):  
Hephzibah Oluwatoyin Ajulo ◽  
Matthew Olugbenga Ajulo ◽  
N. S. E. Udo Ekereumoh
Keyword(s):  
Escherichia Coli ◽  
Bacterial Load ◽  
Bacterial Count ◽  
Viable Count ◽  
Public Health Issue ◽  
Isolation And Identification ◽  
Goat Meat ◽  
E Coli ◽  
Source Of Infection ◽  
Meat Samples

Introduction: In Nigeria, abattoirs have become a source of infection and pollution, attracting domestic animals, wild carnivores and rodents due to lack of adequate slaughtering and disposal facilities. Improper processing of meat consumed by the majority of people in Nigeria is a serious public health issue. Aims: This study was aimed at isolating, characterizing, and identifying Salmonella sp. and Escherichia coli from raw goat meat in Uyo metropolis. Study Design: Fresh goat meat samples were collected from different locations within Uyo metropolis namely; such as goat meat collected at Itam junction market (GTI), Anua junction market (GTA), Ikot Okubo junction market (GTO), Itak Uyo market (GTU), Etuk market (GTE), Ndueh Otong market (GTN) and Mbiere Ebeh market (GTM). Results: The analysis of fresh raw goat meat in Uyo metropolis showed that the total viable count of bacterial load detected on the fresh raw goat meat samples ranged from 9.1X102cfu/g to 1.07X104cfu/g. The highest bacterial count for E. coli was obtained from raw goat meat obtained from GTA1 (3.4X103 cfu/g) followed by GTM2 (3.2X103 cfu/g). The highest bacterial count for Salmonella was obtained from raw goat meat obtained from GTO1 (1.07X104) followed by GTM 2 (1.02X104). The result showed that in addition to E. coli (100%) that was found in all goat meat samples, the most common isolated microorganisms from the fresh raw goat meat samples was Salmonella choleraesuis (38.8%) followed by Salmonella salaemae (34.4%) and Salmonella kauffmanni (9.5%) respectively. Conclusion: This study has indicated high microbial contamination of Escherichia coli and Salmonella sp. in the raw goat meats sold at the selected junctions of Uyo metropolis which suggested a high level of contamination of raw goat meats use for consumed in homes within Uyo metropolis.

scholarly journals Escherichia Coli O157:H7: Distribution, molecular characterization, antimicrobial resistance patterns and source of contamination of sheep and goat carcasses at an export Abattoir, Mojdo, Ethiopia

2019 ◽  
Author(s):  
Solomon Abreham ◽  
Akafete Teklu ◽  
Eric Cox ◽  
Tesfaye Sisay Tessema
Keyword(s):  
Escherichia Coli ◽  
Molecular Characterization ◽  
Virulence Genes ◽  
Antibiotic Sensitivity ◽  
Latex Agglutination ◽  
Human Infection ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Source Of Infection ◽  
Resistance Patterns

Abstract Background : Cattle have been identified as a major reservoir of E. coli O157:H7 for human infection; the ecology of the organism in sheep and goats is less understood. This study was carried out to determine prevalence, source of infection, antibiotic resistance and molecular characterization of Escherichia coli O157: H7 isolated from sheep and goat. Methods : Systematic random sampling was carried out at Modjo export abattoir, Ethiopia, from November 2012 to April 2013 to collect 408 samples from 72 sheep and 32 goats. Samples collected were skin swabs, fecal samples, intestinal mucosal swabs and the inside and outside part of carcasses as well as carcass in contacts such as workers hands, knife, hook and carcass washing water. Then, samples were processed following standard bacteriological procedures. Non-Sorbitol fermenting colonies were tested on latex agglutination test and the positives are subjected to PCR for detection of attaching and effacing genes ( eaeA) and shiga toxin producing genes ( stx1 and stx2 ). All E. coli O157:H7 isolates were checked for their susceptibility pattern towards 15 selected antibiotics. Results : E. coli O157:H7 were detected in only 20/408 samples (4.9%). Among these 20 positive samples, 70% (14/20), 25% (5/20) and 5% (1/20) were from sheep, goats and knife samples, respectively. No significant associations were found between carcasses and the assumed sources of contaminations. Of all the 20 isolates virulence genes were found in 10 (50%) of them; 3 (15%) with only the eaeA gene and 7(35%) expressing eaeA and stx2 genes. All the isolates were susceptible to Norfloxacin (NOR) (100%). Conclusions : The presence of virulence genes shows E. coli O157:H7 is a potential source of human infection in Ethiopia. Key words : Abattoir, antibiotic sensitivity, CT-SMAC, E. coli O157:H7, IMS, Latex agglutination, multiplex PCR.

Sign in / Sign up

Export Citation Format

Share Document