Concentrations of Escherichia coli and Genetic Diversity and Antibiotic Resistance Profiling of Salmonella Isolated from Irrigation Water, Packing Shed Equipment, and Fresh Produce in Texas

2005 ◽  
Vol 68 (1) ◽  
pp. 70-79 ◽  
Author(s):  
E. A. DUFFY ◽  
L. M. LUCIA ◽  
J. M. KELLS ◽  
A. CASTILLO ◽  
S. D. PILLAI ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Genetic Diversity ◽  
Irrigation Water ◽  
Pathogenic Bacteria ◽  
Susceptibility Testing ◽  
Fresh Produce ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Element Sequence

Fresh produce has been repeatedly implicated as a vehicle in the transmission of foodborne gastroenteritis. In an effort to assess the risk factors involved in the contamination of fresh produce with pathogenic bacteria, a total of 1,257 samples were collected from cantaloupe, oranges, and parsley (both in the field and after processing) and from the environment (i.e., irrigation water, soil, equipment, etc.). Samples were collected twice per season from two production farms per commodity and analyzed for the presence of Salmonella and Escherichia coli. E. coli was detected on all types of commodities (cantaloupe, oranges, and parsley), in irrigation water, and on equipment surfaces. A total of 25 Salmonella isolates were found: 16 from irrigation water, 6 from packing shed equipment, and 3 from washed cantaloupes. Salmonella was not detected on oranges or parsley. Serotyping, pulsed-field gel electrophoresis (PFGE), and repetitive element sequence-based PCR (rep-PCR) assays were applied to all Salmonella isolates to evaluate the genetic diversity of the isolates and to determine relationships between sources of contamination. Using PFGE, Salmonella isolates obtained from irrigation water and equipment were determined to be different from cantaloupe isolates; however, DNA fingerprinting did not conclusively define relationships between contamination sources. All Salmonella isolates were subjected to antimicrobial susceptibility testing using the disk diffusion method, and 20% (5 of 25) of the isolates had intermediate sensitivity to streptomycin. One Salmonella isolate from cantaloupe was resistant to streptomycin.

scholarly journals Fecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae in hospital and community settings in Chad

2019 ◽  
Vol 8 (1) ◽  
Author(s):  
Oumar Ouchar Mahamat ◽  
Abdelsalam Tidjani ◽  
Manon Lounnas ◽  
Mallorie Hide ◽  
Julio Benavides ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pathogenic Bacteria ◽  
Hospitalized Patients ◽  
Diffusion Method ◽  
Community Settings ◽  
Carriage Rate ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Fecal Carriage ◽  
Extended Spectrum

Abstract Background Fecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) remains poorly documented in Africa. The objective of this study was to determine the prevalence of ESBL-PE fecal carriage in Chad. Methods In total, 200 fresh stool samples were collected from 100 healthy community volunteers and 100 hospitalized patients from January to March 2017. After screening using ESBL-selective agar plates and species identification by MALDI-TOF mass spectrometry, antibiotic susceptibility was tested using the disk diffusion method, and ESBL production confirmed with the double-disc synergy test. The different ESBL genes in potential ESBL-producing isolates were detected by PCR and double stranded DNA sequencing. Escherichia coli phylogenetic groups were determined using a PCR-based method. Results ESBL-PE fecal carriage prevalence was 44.5% (51% among hospitalized patients vs 38% among healthy volunteers; p < 0.05). ESBL-producing isolates were mostly Escherichia coli (64/89) and Klebsiella pneumoniae (16/89). PCR and sequencing showed that 98.8% (87/89) of ESBL-PE harbored blaCTX-M genes: blaCTX-M-15 in 94.25% (82/87) and blaCTX-M-14 in 5.75% (5/87). Phylogroup determination by quadruplex PCR indicated that ESBL-producing E. coli isolates belonged to group A (n = 17; 27%), C (n = 17; 27%), B2 (n = 9; 14%), B1 (n = 8; 13%), D (n = 8; 13%), E (n = 1; 1.6%), and F (n = 1; 1.6%). The ST131 clone was identified in 100% (9/9) of E. coli B2 strains. Conclusions The high fecal carriage rate of ESBL-PE associated with CTX-M-15 in hospital and community settings of Chad highlights the risk for resistance transmission between non-pathogenic and pathogenic bacteria.

scholarly journals Identification of Extended-Spectrumβ-LactamasesEscherichia coliStrains Isolated from Market Garden Products and Irrigation Water in Benin

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Wassiyath Moussé ◽  
Haziz Sina ◽  
Farid Baba-Moussa ◽  
Pacôme A. Noumavo ◽  
Nadège A. Agbodjato ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Susceptibility ◽  
Irrigation Water ◽  
Food Habits ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Pcr Method ◽  
Horticultural Products

The present study aimed at biochemical and molecular characterization ofEscherichia colistrains isolated from horticultural products and irrigation water of Cotonou. The samples were collected from 12 market gardeners of 4 different sites. Rapid’E. colimedium was used for identification ofE. colistrains and the antimicrobial susceptibility was performed by the agar disk diffusion method. Theβ-lactamases production was sought by the liquid acidimetric method. The genes coding forβ-lactamases and toxins were identified by PCR method. The results revealed that about 34.95% of the analyzed samples were contaminated byE. coli. Cabbages were the most contaminated byE. coli(28.26%) in dry season. All isolated strains were resistant to amoxicillin. The penicillinase producingE. colicarriedblaTEM(67.50%),blaSHV(10%), andblaCTX-M(22.50%) genes. The study revealed that the resistance genes such as SLTI (35.71%), SLTII (35.71%), ETEC (7.15%), and VTEC (21.43%) were carried. Openly to the found results and considering the importance of horticultural products in Beninese food habits, it is important to put several strategies aiming at a sanitary security by surveillance and sensitization of all the actors on the risks of some practices.

scholarly journals Prevalence of antimicrobial-resistant Escherichia coli from raw vegetables in Lebanon

2016 ◽  
Vol 10 (04) ◽  
pp. 354-362 ◽  
Author(s):  
Dima Faour-Klingbeil ◽  
Victor Kuri ◽  
Sukayna Fadlallah ◽  
Ghassan M. Matar
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Agents ◽  
Risk Mitigation ◽  
Fresh Produce ◽  
Mitigation Strategies ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Post Harvest ◽  
Fresh Vegetables

Introduction: Fresh produce has been implicated in a number of documented outbreaks of foodborne illness caused by bacteria, viruses, and parasites. Shiga toxin-producing Escherichia coli (STEC) have been detected on vegetables, raising concerns about the prevalence of E. coli contamination in produce, which can take place at various points from farm to fork. This study aimed to detect the presence of STEC and multidrug-resistant (MDR) E. coli on fresh vegetables and water from different sources along the fresh produce supply chain in Lebanon. Methodology: E. coli isolates (n = 60) were group serotyped using trivalent antisera (trivalent 1 [O111+O55+O26], trivalent 2 [O86+O119+O127], trivalent 3 [O125; O126; O128], and trivalent 4 [O114+O124+O142]) and tested for stx1 and stx2 genes by polymerase chain reaction (PCR) assay. Resistance to antimicrobial agents was determined using the disk diffusion method. Results: The virulence genes stx1 and stx2 were not detected in any of the isolates. However, 60% of the isolates were MDR and predominantly observed in trivalent 2 (32%). It is postulated that the inadequate post-harvest washing contributed to transmission of antimicrobial-resistant E. coli at wholesale and retail levels. Fresh vegetables harbor MDR E. coli and their consumption poses risks of increasing the reservoir of antimicrobial resistance in the intestines of the Lebanese population. Conclusions: Greater emphasis should be placed on vigilant sanitation measures at the consumption level, and effective national risk mitigation strategies are crucial to minimize fecal contamination in the early stages of production, particularly in the post-harvest washing processes.

scholarly journals Phenotypic Antimicrobial Susceptibility of Escherichia coli from Raw Meats, Ready-to-Eat Meats, and Their Related Samples in One Health Context

2021 ◽  
Vol 9 (2) ◽  
pp. 326
Author(s):  
Frederick Adzitey ◽  
Nurul Huda ◽  
Amir Husni Mohd Shariff
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Antimicrobial Susceptibility ◽  
Resistance Index ◽  
Diffusion Method ◽  
Resistant Bacteria ◽  
Disk Diffusion Method ◽  
E Coli ◽  
The Usa ◽  
Raw Meats

Meat is an important food source that can provide a significant amount of protein for human development. The occurrence of bacteria that are resistant to antimicrobials in meat poses a public health risk. This study evaluated the occurrence and antimicrobial resistance of E. coli (Escherichia coli) isolated from raw meats, ready-to-eat (RTE) meats and their related samples in Ghana. E. coli was isolated using the USA-FDA Bacteriological Analytical Manual and phenotypic antimicrobial susceptibility test was performed by the disk diffusion method. Of the 200 examined meats and their related samples, 38% were positive for E. coli. Notably, E. coli was highest in raw beef (80%) and lowest in RTE pork (0%). The 45 E. coli isolates were resistant ≥ 50% to amoxicillin, trimethoprim and tetracycline. They were susceptible to azithromycin (87.1%), chloramphenicol (81.3%), imipenem (74.8%), gentamicin (72.0%) and ciprofloxacin (69.5%). A relatively high intermediate resistance of 33.0% was observed for ceftriaxone. E. coli from raw meats, RTE meats, hands of meat sellers and working tools showed some differences and similarities in their phenotypic antimicrobial resistance patterns. Half (51.1%) of the E. coli isolates exhibited multidrug resistance. The E. coli isolates showed twenty-two different resistant patterns, with a multiple antibiotic resistance index of 0.0 to 0.7. The resistant pattern amoxicillin (A, n = 6 isolates) and amoxicillin-trimethoprim (A-TM, n = 6 isolates) were the most common. This study documents that raw meats, RTE meats and their related samples in Ghana are potential sources of antimicrobial-resistant E. coli and pose a risk for the transfer of resistant bacteria to the food chain, environment and humans.

scholarly journals Evaluation of extended spectrum beta lactamase enzymes prevalence in clinical isolates of Escherichia coli

2011 ◽  
Vol 2 (1) ◽  
pp. 8
Author(s):  
Ronak Bakhtiari ◽  
Jalil Fallah Mehrabadi ◽  
Hedroosha Molla Agamirzaei ◽  
Ailar Sabbaghi ◽  
Mohammad Mehdi Soltan Dallal
Keyword(s):  
Escherichia Coli ◽  
Disk Diffusion ◽  
Confirmatory Test ◽  
Diffusion Method ◽  
Multi Drug Resistance ◽  
Beta Lactamase ◽  
Disk Diffusion Method ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Extended Spectrum

Resistance to b-lactam antibiotics by gramnegative bacteria, especially <em>Escherichia coli (E. coli)</em>, is a major public health issue worldwide. The predominant resistance mechanism in gram negative bacteria particularly <em>E. coli </em>is via the production of extended spectrum beta lactamase (ESBLs) enzymes. In recent years, the prevalence of b-lactamase producing organisms is increased and identification of these isolates by using disk diffusion method and no-one else is not satisfactory. So, this investigation focused on evaluating the prevalence of ESBL enzymes by disk diffusion method and confirmatory test (Combined Disk). Five hundred clinical samples were collected and 200 <em>E. coli </em>isolates were detected by standard biochemical tests. To performing initial screening of ESBLs was used from Disk diffusion method on <em>E. coli </em>isolates. A confirmation test (Combined Disk method) was performed on isolates of resistant to cephalosporin's indicators. Up to 70% isolates exhibited the Multi Drug Resistance phenotype. In Disk diffusion method, 128(64%) <em>E. coli </em>isolates which resistant to ceftazidime and cefotaxime while in Combined Disk, among 128 screened isolates, 115 (89.8%) isolates were detected as ESBLs producers. This survey indicate beta lactamase enzymes are playing a significant role in antibiotic resistance and correct detection of them in phenotypic test by using disk diffusion and combined Disk is essential for accurate recognition of ESBLs.

scholarly journals Occurrence of toxigenic Escherichia coli in raw milk cheese in Brazil

2007 ◽  
Vol 59 (2) ◽  
pp. 508-512 ◽  
Author(s):  
B.R. Paneto ◽  
R.P. Schocken-Iturrino ◽  
C. Macedo ◽  
E. Santo ◽  
J.M. Marin
Keyword(s):  
Escherichia Coli ◽  
Polymerase Chain Reaction ◽  
Antimicrobial Agents ◽  
Raw Milk ◽  
Diffusion Method ◽  
Chain Reaction ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Polymerase Chain ◽  
Raw Milk Cheese

The occurrence of toxigenic Escherichia coli in raw milk cheese was surveyed in Middle Western Brazil. Fifty samples of cheese from different supermarkets were analyzed for E.coli. The isolates were serotyped and screened for the presence of verotoxigenic E. coli (VTEC) and enterotoxigenic E. coli (ETEC) by Polymerase Chain Reaction (PCR). The susceptibility to thirteen antimicrobial agents was evaluated by the disk diffusion method. E.coli were recovered from 48 (96.0%) of the samples. The serogroups identified were O125 (6.0%), O111 (4.0%), O55 (2.0%) and O119 (2.0%). Three (6.0%) and 1(2.0%) of the E.coli isolates were VTEC and ETEC, respectively. Most frequent resistance was observed to the following antimicrobials: cephalothin (60.0%), nalidixic acid (40.0%), doxycyclin (33.0%), tetracycline (31.0%) and ampicillin (29.0%).

scholarly journals Molecular types, virulence profiles and antimicrobial resistance of Escherichia coli causing bovine mastitis

2019 ◽  
Vol 6 (1) ◽  
pp. e000369 ◽  
Author(s):  
Magdalena Nüesch-Inderbinen ◽  
Nadine Käppeli ◽  
Marina Morach ◽  
Corinne Eicher ◽  
Sabrina Corti ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Bovine Mastitis ◽  
Tetracycline Resistance ◽  
Diffusion Method ◽  
Sample Population ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Phylogenetic Grouping ◽  
Resistance Rates ◽  
Susceptibility Profiles

BackgroundEscherichia coli is an important aetiological agent of bovine mastitis worldwide.MethodsIn this study, 82 E. coli from bovine mastitis milk samples from 49 farms were analysed for their genetic diversity using phylogenetic grouping and multilocus sequence typing. The isolates were examined by PCR for a selection of virulence factors (VFs). Antimicrobial susceptibility profiles were assessed using the disk diffusion method.ResultsThe most prevalent phylogroups were group B1 (41.5 per cent of the isolates) and group A (30.5 per cent). A variety of 35 different sequence types (STs) were identified, including ST1125 (11 per cent), ST58 (9.8 per cent), ST10 (8.5 per cent) and ST88 (7.3 per cent). Aggregate VF scores (the number of unique VFs detected for each isolate) ranged from 1 to 3 for 63.4 per cent of the isolates and were at least 4 for 12.2 per cent. For 24.4 per cent of the isolates, the score was 0. The three most frequent VFs were traT, fyuA and iutA. The majority (72 per cent) of the isolates harboured traT. The majority (68.3 per cent) of the isolates were fully susceptible to all antimicrobials tested, with 22 per cent resistant to ampicillin and 14.6 per cent to tetracycline. Resistance rates were low for gentamicin (3.7 per cent), amoxicillin/clavulanic acid (2.4 per cent) and ceftiofur (1.2 per cent), respectively.ConclusionAmong the study’s sample population, E. coli strains were genotypically diverse, even in cows from the same farm, although some STs occurred more frequently than others. Susceptibility to clinically relevant compounds remained high.

scholarly journals A Preliminary Study: Antibiotic Resistance Patterns of Escherichia coli and Enterococcus Species from Wildlife Species Subjected to Supplementary Feeding on Various South African Farms

Animals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 396 ◽  
Author(s):  
Michaela Sannettha van den Honert ◽  
Pieter Andries Gouws ◽  
Louwrens Christiaan Hoffman
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Supplementary Feeding ◽  
Health Concern ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Wildlife Species ◽  
Human Contact ◽  
Resistance Patterns

Studies have shown that antibiotic resistance among wild animals is becoming a public health concern, owing to increased contact and co-habitation with domestic animals that, in turn, results in increased human contact, indirectly and directly. This type of farming practice intensifies the likelihood of antibiotic resistant traits in microorganisms transferring between ecosystems which are linked via various transfer vectors, such as rivers and birds. This study aimed to determine whether the practice of wildlife supplementary feeding could have an influence on the antibiotic resistance of the bacteria harboured by the supplementary fed wildlife, and thus play a potential role in the dissemination of antibiotic resistance throughout nature. Escherichia coli and Enterococcus were isolated from the faeces of various wildlife species from seven different farms across South Africa. The Kirby-Bauer disk diffusion method was used according to the Clinical and Laboratory Standards Institute 2018 guidelines. The E. coli (F: 57%; N = 75% susceptible) and Enterococcus (F: 67%; N = 78% susceptible) isolates from the supplementary fed (F) wildlife were in general, found to be more frequently resistant to the selection of antibiotics than from those which were not supplementary fed (N), particularly towards tetracycline (E. coli F: 56%; N: 71%/Enterococcus F: 53%; N: 89% susceptible), ampicillin (F: 82%; N = 95% susceptible) and sulphafurazole (F: 68%; N = 98% susceptible). Interestingly, high resistance towards streptomycin was observed in the bacteria from both the supplementary fed (7% susceptible) and non-supplementary fed (6% susceptible) wildlife isolates. No resistance was found towards chloramphenicol and ceftazidime.

scholarly journals Unstable Mechanisms of Resistance to Inhibitors of Escherichia coli Lipoprotein Signal Peptidase

mBio ◽  
2020 ◽  
Vol 11 (5) ◽  
Author(s):  
Homer Pantua ◽  
Elizabeth Skippington ◽  
Marie-Gabrielle Braun ◽  
Cameron L. Noland ◽  
Jingyu Diao ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Susceptibility ◽  
Pathogenic Bacteria ◽  
Susceptibility Testing ◽  
Regulatory Elements ◽  
Signal Peptidase ◽  
Type Ii ◽  
Mechanisms Of Resistance ◽  
Content Type ◽  
E Coli

ABSTRACT Clinical development of antibiotics with novel mechanisms of action to kill pathogenic bacteria is challenging, in part, due to the inevitable emergence of resistance. A phenomenon of potential clinical importance that is broadly overlooked in preclinical development is heteroresistance, an often-unstable phenotype in which subpopulations of bacterial cells show decreased antibiotic susceptibility relative to the dominant population. Here, we describe a new globomycin analog, G0790, with potent activity against the Escherichia coli type II signal peptidase LspA and uncover two novel resistance mechanisms to G0790 in the clinical uropathogenic E. coli strain CFT073. Building on the previous finding that complete deletion of Lpp, the major Gram-negative outer membrane lipoprotein, leads to globomycin resistance, we also find that an unexpectedly modest decrease in Lpp levels mediated by insertion-based disruption of regulatory elements is sufficient to confer G0790 resistance and increase sensitivity to serum killing. In addition, we describe a heteroresistance phenotype mediated by genomic amplifications of lspA that result in increased LspA levels sufficient to overcome inhibition by G0790 in culture. These genomic amplifications are highly unstable and are lost after as few as two subcultures in the absence of G0790, which places amplification-containing resistant strains at high risk of being misclassified as susceptible by routine antimicrobial susceptibility testing. In summary, our study uncovers two vastly different mechanisms of resistance to LspA inhibitors in E. coli and emphasizes the importance of considering the potential impact of unstable and heterogenous phenotypes when developing antibiotics for clinical use. IMPORTANCE Despite increasing evidence suggesting that antibiotic heteroresistance can lead to treatment failure, the significance of this phenomena in the clinic is not well understood, because many clinical antibiotic susceptibility testing approaches lack the resolution needed to reliably classify heteroresistant strains. Here we present G0790, a new globomycin analog and potent inhibitor of the Escherichia coli type II signal peptidase LspA. We demonstrate that in addition to previously known mechanisms of resistance to LspA inhibitors, unstable genomic amplifications containing lspA can lead to modest yet biologically significant increases in LspA protein levels that confer a heteroresistance phenotype.

scholarly journals Detection of plasmid-mediated qnr genes among the quinolone-resistant Escherichia coli isolates in Iran

2014 ◽  
Vol 8 (07) ◽  
pp. 818-822 ◽  
Author(s):  
Farzaneh Firoozeh ◽  
Mohammad Zibaei ◽  
Younes Soleimani-Asl
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Urinary Tract Infections ◽  
Quinolone Resistance ◽  
Diffusion Method ◽  
Chain Reaction ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Polymerase Chain ◽  
Tract Infections

Introduction: Plasmid-mediated quinolone resistance, which complicates treatment, has been increasingly identified in Escherichia coli isolates worldwide. The purpose of this study was to identify the plasmid-mediated qnrA and qnrB genes among the quinolone-resistant Escherichia coli isolated from urinary tract infections in Iran. Methodology: A total of 140 Escherichia coli isolates were collected between March and October 2012 from urinary tract infections in Khorram Abad, Iran. All isolates were tested for quinoloe resistance using the disk diffusion method. Also, all quinolone-resistant isolates were screened for the presence of the qnrA and qnrB genes by polymerase chain reaction. Minimum inhibitory concentrations (MICs) of ciprofloxacin for the qnr-positive isolates were determined. Results: One hundred sixteen (82.8%) of 140 Escherichia coli isolates were nalidixic acid-resistant; among them, 14 (12.1%) and 9 (7.8%) were qnrA and qnrB-positive, respectively. Two quinolone-resistant isolates harbored both qnrA and qnrB. Among 63 ciprofloxacin-resistant isolates, 14 (22.2%) and 9 (14.3%) were found to carry qnrA and qnrB genes, respectively. The ciprofloxacin MIC range was 0.25–512 μg/mL for 23 qnr-positive Escherichia coli isolates, 18 of which had MICs values of 4–512 μg/mL. Conclusion: Our study shows that the frequency of plasmid-mediated quinolone resistance genes among E. coli isolates in Iran is high.

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