Pathogenic E. Coli

Whole genome sequencing (WGS) has proven to be the ultimate tool for bacterial isolate characterization and relatedness determination. However, standardized and harmonized workflows, e.g. for DNA extraction, are required to ensure robust and exchangeable WGS data. Data sharing between (inter)national laboratories is essential to support foodborne pathogen control, including outbreak investigation. This study evaluated eight commercial DNA preparation kits for their potential influence on: (i) DNA quality for Nextera XT library preparation; (ii) MiSeq sequencing (data quality, read mapping against plasmid and chromosome references); and (iii) WGS data analysis, i.e. isolate characterization (serotyping, virulence and antimicrobial resistance genotyping) and phylogenetic relatedness (core genome multilocus sequence typing and single nucleotide polymorphism analysis). Shiga toxin-producing Escherichia coli (STEC) was selected as a case study. Overall, data quality and inferred phylogenetic relationships between isolates were not affected by the DNA extraction kit choice, irrespective of the presence of confounding factors such as EDTA in DNA solution buffers. Nevertheless, completeness of STEC characterization was, although not substantially, influenced by the plasmid extraction performance of the kits, especially when using Nextera XT library preparation. This study contributes to addressing the WGS challenges of standardizing protocols to support data portability and to enable full exploitation of its potential. Whole genome sequencing (WGS) is being or has already been implemented internationally in foodborne pathogen surveillance and outbreak investigations . Thanks to its single nucleotide resolution, WGS provides superior isolate characterization and (sub)typing. This enables increased pathogen insight, and linking of human illness to specific foods or production environments with an unprecedented level of confidence 5 . There are however several challenges to be considered to fully exploit its potential, including the standardization and harmonization of laboratory and computational workflows. Several consortia 6-9 are currently addressing

Whole genome sequencing (WGS) has proven to be the ultimate tool for bacterial isolate characterization and relatedness determination. However, standardized and harmonized workflows, e.g. for DNA extraction, are required to ensure robust and exchangeable WGS data. Data sharing between (inter)national laboratories is essential to support foodborne pathogen control, including outbreak investigation. This study evaluated eight commercial DNA preparation kits for their potential influence on: (i) DNA quality for Nextera XT library preparation; (ii) MiSeq sequencing (data quality, read mapping against plasmid and chromosome references); and (iii) WGS data analysis, i.e. isolate characterization (serotyping, virulence and antimicrobial resistance genotyping) and phylogenetic relatedness (core genome multilocus sequence typing and single nucleotide polymorphism analysis). Shiga toxin-producing Escherichia coli (STEC) was selected as a case study. Overall, data quality and inferred phylogen...

Commercial Concentrated Animal Feeding Operations (CAFOs) produce large quantities of waste material from the animals being housed in them. These feedlots found across the United States contain livestock that produce waste that results in hazardous runoff. Water sources surrounding CAFOs become contaminated making the water unusable for humans, livestock, and uninhabitable for aquatic life. This study examines how CAFOs affect water sources by testing for Escherichia coli (E. coli) content in bodies of water near CAFOs. We hypothesized that the level of E. coli content in water samples near CAFO sites will be higher than in water samples not near CAFOs sites. To test our hypothesis, private drinking water bacteriological tests were performed on water samples sourced within one mile of a CAFO and then compared to water samples sourced more than five miles from the nearest CAFO. We found an increase in the E. coli concentration in water source samples closer to CAFOs. This research is crucial to understanding the impact that CAFOs have on the environment. It also provides important information for those living near CAFOs so that they can make informed decisions regarding their use of nearby water sources.

Ipsat P1A is a recombinant β-lactamase which degrades antibiotic residue in the gastrointestinal tract. In an open-label, single-center controlled trial, 36 healthy subjects were randomized to receive (i) ampicillin (1 g intravenously [i.v.] every 6 h [q6h]), (ii) oral P1A recombinant β-lactamase (8.2 mg q6h), or (iii) ampicillin (1 g i.v. q6h) in combination with oral P1A recombinant β-lactamase (8.2 mg q6h) for 5 days. Fecal samples were collected before treatment, during treatment (days 3 to 5), and at follow-up (day 12). The primary end points were (i) changes in gastrointestinal microflora (determined by temperature gradient gel electrophoresis [TGGE]) and (ii) emergence of bacterial resistance (determined by conventional microbiology and PCR of TEM β-lactamase genes). Thirty-five subjects completed the study. The mean similarity percentages of TGGE profiles between baseline and each treatment day sample were significantly lower for the ampicillin group than for the group recei...

Background: Fluoroquinolone resistant Escherichia coli isolates have become an important challenge in healthcare settings in Iran. In this study, we have determined Fluoroquinolone resistant E. coli isolates (from both outpatients and inpatients) and evaluated mutations of gyrA and parC within the quinolone resistance-determining regions (QRDR) of these clinical isolates. Materials and methods: Clinical isolates were recovered from the urine sample of patients with urinary tract infections admitted at Alzahra hospital, Iran, between September and February 2013. We assessed antimicrobial susceptibility of all isolates and determined mutations in QRDR of gyrA and parC genes from 13 fluoroquinolone-resistant isolates by DNA sequencing. Results: A total of 135 E. coli strains were obtained from 135 patients (91 outpatients and 44 inpatients). The resistance rate of fluoroquinolones (Ciprofloxacin, Norfloxacin and Ofloxacin) among our strains was 45.2%. Two E. coli isolates were shown just a single mutation, but other isolates possessed 2-5 mutations in gyrA and parC genes. Mutations in the QRDR regions of gyrA were at positions Ser83 and Asp87 and parC at positions Ser80, Glu84, Gly78. Conclusions: Ciprofloxacin is the most common antimicrobial agent used for treating urinary tract infections (UTIs) in healthcare settings in Iran. Accumulation of different substitutions in the QRDR regions of gyrA and parC confers high-level resistance of fluoroquinolones in clinical isolates.

Aquatic environment contamination remains a foremost global public health hazards, and symbolizes a significant reservoir of releasing antibiotic resistant bacteria. The survival of Escherichia coli in aquatic environments serves as a potential reservoir of antibiotic resistance, encompassing but not restricted to a plasmid-mediated quinolone resistance (PMQR) mechanism. The current study aimed to detect the presence of the PMQR-qnrA gene in quinolone-resistant E. coli isolates. Sixty-one waterborne E. coli with known phylogroups/subgroups isolated from the Al-Hillah River in Babylon Province, Iraq, were screened for the phenotypic resistance to third-generation quinolones (levofloxacin and ofloxacin) and were further analysed for the presence of the qnrA gene using polymerase chain reaction (PCR). Fifty-seven (93.4%) of 61 E. coli isolates were levofloxacin-resistant, and 55 (90.2%) were ofloxacin-resistant. Among the 57 quinolone-resistant E. coli, 40 (65.57%) isolates were found ...

Background We aimed to investigate the prevalence, molecular epidemiology and prevalence factors for Extended Spectrum β-Lactamase-producing Enterobacteriaceae (ESBL-E) shedding by race horses. A cross-sectional study was performed involving fecal samples collected from 169 Thoroughbred horses that were housed at a large racing facility in Ontario, Canada. Samples were enriched, plated on selective plates, sub-cultured to obtain pure cultures and ESBL production was confirmed. Bacterial species were identified and antibiotic susceptibility profiles were assessed. E. coli sequence types (ST) and ESBL genes were determined using multilocus sequence type (MLST) and sequencing. Whole genome sequencing was performed to isolates harboring CTX-M-1 gene. Medical records were reviewed and associations were investigated. Results Adult horses (n = 169), originating from 16 different barns, were sampled. ESBL-E shedding rate was 12% (n = 21/169, 95% CI 8–18%); 22 ESBL-E isolates were molecularl...

Escherichia coli is a natural inhabitant of the gut and E. coli levels in water are considered internationally to be an indication of faecal contamination. Although not usually pathogenic, E. coli has been linked to numerous foodborne disease outbreaks, especially those associated with fresh produce. One of the most common ways through which E. coli can be transferred onto fresh produce is if contaminated water is used for irrigation. In this study, a total of 81 confirmed E. coli strains were isolated from the Plankenburg River as part of three separate studies over 3 years. During sampling, E. coli levels in the river were above the accepted levels set by the World Health Organization and the South African Department of Water Affairs and Forestry for safe irrigation of fresh produce, which indicates that transfer of E. coli during irrigation is highly probable. Multiplex polymerase chain reaction screening for pathogenic gene sequences revealed one enteroaggregative positive strai...

Background Enterotoxigenic Escherichia coli (ETEC) is a common cause of bacterial infection leading to acute watery diarrhea in infants and young children as well as in travellers to ETEC endemic countries. Ciprofloxacin is a broad-spectrum antimicrobial agent nowadays used for the treatment of diarrhea. This study aimed to characterize ciprofloxacin resistant ETEC strains isolated from diarrheal patients in Bangladesh. Methods A total of 8580 stool specimens from diarrheal patients attending the icddr,b Dhaka hospital was screened for ETEC between 2005 and 2009. PCR and Ganglioside GM1-Enzyme Linked Immuno sorbent Assay (ELISA) was used for detection of Heat labile (LT) and Heat stable (ST) toxins of ETEC. Antimicrobial susceptibilities for commonly used antibiotics and the minimum inhibitory concentration (MIC) of nalidixic acid, ciprofloxacin and azithromycin were examined. DNA sequencing of representative ciprofloxacin resistant strains was performed to analyze mutations of the quinolone resistance-determining region of gyrA, gyrB, parC and parE. PCR was used for the detection of qnr, a plasmid mediated ciprofloxacin resistance gene. Clonal variations among ciprofloxacin resistant (Cip R) and ciprofloxacin susceptible (Cip S) strains were determined by Pulsed-field gel electrophoresis (PFGE). Results Among 1067 (12%) ETEC isolates identified, 42% produced LT/ST, 28% ST and 30% LT alone. Forty nine percent (n = 523) of the ETEC strains expressed one or more of the 13 tested colonization factors (CFs) as determined by dot blot immunoassay. Antibiotic resistance of the ETEC strains was observed as follows: ampicillin 66%, azithromycin 27%,

People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:

Background: Escherichia coli (E. coli), the main human gut microorganism, is one of the evolved superbugs because of acquiring antimicrobial resistance (AMR) determinants via horizontal gene transfer (HGT). Purpose: This study aimed to screen isolates of gut commensal E. coli from healthy adult individuals for antimicrobial susceptibility and plasmid-mediated AMR encoding genes. Methods: Gut commensal E. coli bacteria were isolated from fecal samples that were taken from healthy adult individuals and investigated phenotypically for their antimicrobial susceptibility against diverse classes of antimicrobials using the Kirby Bauer disc method. PCR-based molecular assays were carried out to detect diverse plasmid-carried AMR encoding genes and virulence genes of different E. coli pathotypes (eaeA, stx, ipaH, est, elt, aggR and pCVD432). The examined AMR genes were β-lactam resistance encoding genes (bla CTX-M1 , bla TEM , bla CMY-2), tetracycline resistance encoding genes (tetA, tetB), sulfonamides resistance encoding genes (sul1, sulII), aminoglycoside resistance encoding genes (aac(3)-II, aac(6′)-Ib-cr) and quinolones resistance encoding genes (qnrA, qnrB, qnrS). Results: PCR results revealed the absence of pathotypes genes in 56 isolates that were considered gut commensal isolates. E. coli isolates showed high resistance rates against tested antimicrobial agents belonging to both β-lactams and sulfonamides (42/56, 75%) followed by quinolones (35/56, 62.5%), tetracyclines (31/56, 55.4%), while the lowest resistance rate was to aminoglycosides (24/56, 42.9%). Antimicrobial susceptibility profiles revealed that 64.3% of isolates were multidrug-resistant (MDR). High prevalence frequencies of plasmid-carried AMR genes were detected including bla TEM (64%) sulI (60.7%), qnrA (51.8%), aac(3)-II (37.5%), and tetA (46.4%). All isolates harbored more than one gene with the most frequent genetic profile among isolates was bla TEM-bla CTX-M1-like-qnrA-qnrB-tetA-sulI. Conclusion: Results are significant in the evaluation of plasmid-carried AMR genes in the human gut commensal E. coli, suggesting a potential human health risk and the necessity of strict regulation of the use of antibiotics in Egypt. Commensal E. coli bacteria may constitute a potential reservoir of AMR genes that can be transferred to other bacterial species.

Objective of the study: Escherichia coli bacteria with increased antibiotic resistance represent a serious threat to public health. The aim of this study was to assess Cb6 (E)-1-& effectiveness against microorganisms (4-fluorophenyl), determine the effectiveness of Cb6 (E)-1-(4-fluorophenyl)-3-phenyl prop-2-en-1-one against anti-fungal agents and-3-phenylprop-2-en-1-one against E. coli (Curvularia). StudyDesign:Study was designed by sample collection, culturing, biochemical tests, sensitivity assay and qRT-PCR. Place and Duration: The prospective study was carried out at the University of Agriculture in Faisalabad, Pakistan from 1st February 2019 to 18 th June 2019. Methodology: Through horizontal and vertical gene transfer, Escherichia coli acquired resistance genes and developed resistance against many antibiotic classes. The following genes were examined in the current study in E. coli: Van B, ermC, Iva-A, Qnr-A, Qnr-B, tet M, tet O, and tet W resistance genes. To assess the effectiveness of the antibacterial and antifungal agents, antibiotic sensitivity testing was carried out. Results: E.coli chalcone resistance genes, have displayed highly significant (P 0.0001) expression in the patient sample when compared to the control. Conclusion: It was concluded that the chalcones are highly resistant to E coli in prediction. Van B, erm C, Iva-A, Qnr-A, Qnr-B, tet M, tet O, and tet Ware resistant genes of the Escherichia coli against the Cb6 (E)-1-(4-fluorophenyl)-3-phenyl prop-2-en-1one and it was showed the high expression level.

Fluoroquinolone antibiotics (FQs) have been used worldwide for chemotherapy, animal husbandry, and aquaculture, and the occurrence of FQ-resistant (FQs r) bacteria in natural environments has been reported. Plasmid-mediated transferable quinolone resistance (PMQR) genes are suspected to originate from the chromosomes of water-dwelling bacteria. However, the occurrence of and the potential reservoir of FQs r bacteria and PMQR genes in aquatic environments have not been elucidated. In this study, we detected FQs r bacteria and PMQR genes in aquatic environments in Thailand and Vietnam, and measured FQ contamination. Levels of contamination were greater Thailand (avg. 5130, max 46100 ng L −1) than in Vietnam (avg. 235, max 1130 ng L −1); however, the occurrence of FQs r bacteria was higher in Vietnam (~15%) than in Thailand (~7.0%), suggesting that contamination by FQs is not directly linked to the development of FQs r bacteria. Diverse taxonomic groups of FQs r-bacteria were identified, and one of the PMQR genes, qnrB, was detected from bacteria of environmental origin, not enteric bacteria. This suggests that the environmental bacteria are a potential reservoir of antibiotic resistance determinants even at un-contaminated sites.

Commercial Concentrated Animal Feeding
Operations (CAFOs) produce large quantities of
waste material from the animals being housed in
them. These feedlots found across the United States
contain livestock that produce waste that results in
hazardous runoff. Water sources surrounding CAFOs
become contaminated making the water unusable for
humans, livestock, and uninhabitable for aquatic life.
This study examines how CAFOs affect water sources
by testing for Escherichia coli ( E. coli) content in
bodies of water near CAFOs. We hypothesized that
the level of E. coli content in water samples near
CAFO sites will be higher than in water samples not
near CAFOs sites. To test our hypothesis, private
drinking water bacteriological tests were performed
on water samples sourced within one mile of a CAFO
and then compared to water samples sourced more
than five miles from the nearest CAFO. We found an
increase in the E. coli concentration in water source
samples closer to CAFOs. This research is crucial to
understanding the impact that CAFOs have on the
environment. It also provides important information
for those living near CAFOs so that they can make
informed decisions

The aim of this study was to detect and characterize pathogenic and antibiotic resistant Escherichia coli isolated from slaughterhouse wastewater and the effluents of a municipal wastewater treatment plant (WWTP) in Dakar, Senegal. Genetic markers associated with enterohemorrhagic E. coli (EHEC) and extraintestinal pathogenic E. coli (ExPEC) were screened in 268 E. coli isolates from slaughterhouse and 272 E. coli isolates from WWTP. Concerning antimicrobial resistance, 40 E. coli isolates were studied for each of the two sampling sites. None of the E. coli isolates harboring the genes associated with EHEC was detected in WWTP. Of the 13 tested virulence genes, fuyA and f17 were the most prevalent. The pathogenic and resistant E. coli was found in the raw wastewater and the influent of slaughterhouse. The final rejection used for urban gardening, including the watering of vegetables does not contain E. coli. These results showed that, after treatment, the sanitation risks associated with the reuse water from WWTP were low.

The isolation and screening of antibiotic resistance strains from three samples sites present in and around hospital of Patna resulted in isolation of 300 bacterial isolates. Out of which maximum number of isolates were obtained from site B while site A gave least number of isolates. 89 bacterial strains showed antibiotic resistance. Among these 89 isolates Site B had maximum number of antibiotic resistant isolates (51) followed by site C with 33 isolates. Among the four groups of antibiotic selected for investigation, the isolates showed highest antibiotic resistance against fluoroquinolones with 1, 20 and 14 isolates from site A, site B and site C respectively showing antibiotic resistance. Site B isolates showed significant resistance against group III (aminoglycosides) antibiotic. Site C isolates also showed maximum resistance against Group IV antibiotics followed by Group II, III and Group I. Site A sample showed resistance against Ciprofloxacin, however it showed sensitivity a...

The aim of this study was to detect and characterize pathogenic and antibiotic resistant Escherichia coli isolated from slaughterhouse wastewater and the effluents of a municipal wastewater treatment plant (WWTP) in Dakar, Senegal. Genetic markers associated with enterohemorrhagic E. coli (EHEC) and extraintestinal pathogenic E. coli (ExPEC) were screened in 268 E. coli isolates from slaughterhouse and 272 E. coli isolates from WWTP. Concerning antimicrobial resistance, 40 E. coli isolates were studied for each of the two sampling sites. None of the E. coli isolates harboring the genes associated with EHEC was detected in WWTP. Of the 13 tested virulence genes, fuyA and f17 were the most prevalent. The pathogenic and resistant E. coli was found in the raw wastewater and the influent of slaughterhouse. The final rejection used for urban gardening, including the watering of vegetables does not contain E. coli. These results showed that, after treatment, the sanitation risks associated with the reuse water from WWTP were low.

Participants in an unorganized gathering are potential hosts of diseases, bringing diseases from around the world to be introduced to a large at-risk population. Therefore, we investigated the gene repertoire in 29 Escherichia coli strains linked to urinary tract infection isolated from patients transferred to the hospital after attending an unorganized gathering in Cairo. Virulence and resistance determinants, phenotypic antibiotic resistance, biofilm formation, their serotypes and phylogenetic relationships were analyzed. The 29 tested serovars were phenotypically virulent, with the prevalence of group B2, and resistant to tetracycline, naldixic acid, ampicillin, trimethoprim, neomycin, oxytetracycline and erythromycin encoding the iss virulent gene. A One Health approach is a must to monitor and control E. coli urinary tract infections.

The aim of this study was to detect and characterize pathogenic and antibiotic resistant Escherichia coli isolated from slaughterhouse wastewater and the effluents of a municipal wastewater treatment plant (WWTP) in Dakar, Senegal. Genetic markers associated with enterohemorrhagic E. coli (EHEC) and extraintestinal pathogenic E. coli (ExPEC) were screened in 268 E. coli isolates from slaughterhouse and 272 E. coli isolates from WWTP. Concerning antimicrobial resistance, 40 E. coli isolates were studied for each of the two sampling sites. None of the E. coli isolates harboring the genes associated with EHEC was detected in WWTP. Of the 13 tested virulence genes, fuyA and f17 were the most prevalent. The pathogenic and resistant E. coli was found in the raw wastewater and the influent of slaughterhouse. The final rejection used for urban gardening, including the watering of vegetables does not contain E. coli. These results showed that, after treatment, the sanitation risks associated with the reuse water from WWTP were low.

The aim of this study was to detect and characterize pathogenic and antibiotic resistant Escherichia coli isolated from slaughterhouse wastewater and the effluents of a municipal wastewater treatment plant (WWTP) in Dakar, Senegal. Genetic markers associated with enterohemorrhagic E. coli (EHEC) and extraintestinal pathogenic E. coli (ExPEC) were screened in 268 E. coli isolates from slaughterhouse and 272 E. coli isolates from WWTP. Concerning antimicrobial resistance, 40 E. coli isolates were studied for each of the two sampling sites. None of the E. coli isolates harboring the genes associated with EHEC was detected in WWTP. Of the 13 tested virulence genes, fuyA and f17 were the most prevalent. The pathogenic and resistant E. coli was found in the raw wastewater and the influent of slaughterhouse. The final rejection used for urban gardening, including the watering of vegetables does not contain E. coli. These results showed that, after treatment, the sanitation risks associated with the reuse water from WWTP were low.

The occurrence of antibiotic resistance genes (ARGs) as emerging contaminants is of continued concern for human health. Antibiotics used in aquaculture have promoted the evolution and spread of ARGs. This study aimed to investigate the occurrence of 37 ARGs conferring resistance to six classes of antibiotics in 94 aquatic animals from five cities in southeast coast of China. The results showed that R, II, I, B, A, A, and S were identified as the prominent ARGs with the high detection frequencies ranging from 30.9 to 51.1% in total samples. Then relative expression amount of seven prominent ARGs quantified by qPCR, ranging from 0.003 to 0.065. The S was the most abundant ARG among the seven ARGs. Though A was the second highest detection frequency of ARGs, it was the lowest expression amount ARG. The occurrences and abundances of ARGs in freshwater aquatic animals were greater than those in marine, reflecting the discrepancy of cultivation pattern between the freshwater and marine aq...

Objective: KPC-producing Gram-negative bacilli (GNB) have been described in five continents since KPC were identified in the early 1990s. After full characterization of multi-drug (MD) resistant (R) blood GNB from 2001 07 from 12 healthcare facilities served by a Toronto clinical microbiology laboratory revealed no KPC-producers, a review of 2008 KP was done. Methods: The laboratory information system was used to identify any KP testing meropenem-R (MR) by Vitek 2 from all specimen types received in 2008 from the same 12 healthcare facilities. Any MR-KP detected was investigated using CLSI broth microdilution, the modified Hodge Test and KPC PCR with sequencing. A chart review was completed. Results: A single MR-KP isolate was identified. The modified Hodge Test was positive, and PCR and sequence analysis revealed the isolate contained a bla KPC-3 gene. Based on CLSI or FDA criteria, MIC testing (mg/L) revealed R to piperacillin-tazobactam (MIC > 128/4), ticarcillin/clavulanic acid (MIC > 128/2), ampicillin/sulbactam (MIC > 32/16), ceftazidime and cefepime (MIC > 32), ertapenem (MIC > 8), meropenem and imipenem (MIC > 16), ciprofloxacin (MIC > 4), levofloxacin (MIC > 8), and gemifloxacin (MIC > 1); with intermediate susceptibility to chloramphenicol (MIC 16); and susceptibility to tigecycline (MIC 0.25), doxycycline and minocycline (MIC 4), gentamicin (MIC 4) and amikacin (MIC 16). The KP was isolated once from peritoneal dialysis effluent fluid in Feb 2008 from a 55 year-old female who presented with peritonitis. The KP was not considered to be significant and was not treated. Rectal carriage was not ascertained at the time but was negative when tested 11 months later. The patient had a history of multiple admissions to other Toronto hospitals but had no travel history outside of Toronto within the previous year. Conclusions: This is the first known report of a KPC-producing KP in Toronto, Canada. The patient had no exposures outside of Toronto suggesting local acquisition. More aggressive surveillance in Torontobased laboratories should be done to ascertain the prevalence of KPC in the region. Additional review of carbapenem-susceptible Enterobacteriaceae with reduced susceptibility to carbapenems is ongoing and may reveal additional KPC-producing organisms.

This study was conducted to assess the retail food as a possible vehicle for antimicrobial resistant, particularly quinolones resistant and pathogenic Escherichia coli. We determined the prevalence and characteristics of nalidixic acid (Nal) resistant E. coli isolates from diverse retail food samples. In all, 70 (28%) of 250 E. coli isolates studied were Nal-resistant E. coli and 91% of these were multi-drug resistant. Plasmid mediated quinolone resistance genes were identified in 32 isolates, including aac(6 0)-Ib-cr (n D 16), qnrS1 (n D 11) and qnrB19 (n D 7). Mutations in gyr A and par C genes were detected among 80% of the isolates, and the isolates showed substitution Ser83-Leu and Asp87-Asn in gyrA and Ser80-Ile in parC. In addition, three different gene cassettes were identified (aadA1, aadA7, aac(3)-Id) in 18%. Virulenceassociated genes stx1, eae, sfa, hlyA and stx2 were found in six (8%), three (4%), two (3%), three (4%) and three (4%) isolates, respectively. E. coli isolates of phylogenetic group A were dominant (64%, 45/70). Pulsed field gel electrophoresis revealed none epidemiological relationship between these isolates. The results of this work report the higher frequency of Nal-resistant E. coli isolates from Moroccan retail food samples including MDR and pathogenic isolates.

BackgroundPseudomonas aeruginosa is an opportunistic pathogen and a major cause of infections. Widespread resistance in human infections are increasing the use of last resort antimicrobials such as polymyxins. However, these have been used for decades in veterinary medicine. Companion animals are an understudied source of antimicrobial resistant P. aeruginosa isolates. This study evaluated the susceptibility of P. aeruginosa veterinary isolates to polymyxins to determine whether the veterinary niche represents a potential reservoir of resistance genes for pathogenic bacteria in both animals and humans.Methods and resultsClinical P. aeruginosa isolates (n=24) from UK companion animals were compared for antimicrobial susceptibility to a panel of human-associated isolates (n=37). Minimum inhibitory concentration (MIC) values for polymyxin B and colistin in the companion animals was significantly higher than in human isolates (P=0.033 and P=0.013, respectively). Genotyping revealed that...

People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:

Antimicrobial resistance is known to be an emerging problem, but the extent of the issue remains incomplete. The aim of this study was to determine the presence or absence of nine resistance genes (blaTEM , catI, mecA, qnrS, sulI, sulII, tet(A), tet(Q), vanA) in the faeces of 141 pigeons from four urban parks in Alajuela, Guadalupe, Tres Ríos and San José in Costa Rica. The genes were identified by real-time PCR directly from enema samples. About 30% of the samples were positive for genes catI and sulI; between 13% and 17% were positive for qnrS, sulII, tet(A) and tet(Q); and 4% were positive for blaTEM . The mecA and vanA genes were not detected. The average of antimicrobial resistance genes detected per pigeon was 2. Eight different patterns of resistance were identified, without differences in the sampling areas, being the most common pattern 2 (sulII positive samples). During rainy season, the genes more frequently found were sulI and tet(A). In conclusion, the urban inhabiting ...

Antibiotic selection pressure and genetic associations may lead to the cooccurrence of resistance and virulence in individual pathogens. However, there is a lack of rigorous epidemiological evidence that demonstrates the cooccurrence of resistance and virulence at the population level. Using samples from a population-based case-control study in 25 villages in rural Ecuador, we characterized resistance to 12 antibiotics among pathogenic ( n = 86) and commensal ( n = 761) Escherichia coli isolates, classified by the presence or absence of known diarrheagenic virulence factor genes. The prevalences of resistance to single and multiple antibiotics were significantly higher for pathogenic isolates than for commensal isolates. Using a generalized estimating equation, antibiotic resistance was independently associated with virulence factor carriage, case status, and antibiotic use (for these respective factors: odds ratio [OR] = 3.0, with a 95% confidence interval [CI] of 1.7 to 5.1; OR = ...

Participants in an unorganized gathering are potential hosts of diseases, bringing diseases from around the world to be introduced to a large at-risk population. Therefore, we investigated the gene repertoire in 29 Escherichia coli strains linked to urinary tract infection isolated from patients transferred to the hospital after attending an unorganized gathering in Cairo. Virulence and resistance determinants, phenotypic antibiotic resistance, biofilm formation, their serotypes and phylogenetic relationships were analyzed. The 29 tested serovars were phenotypically virulent, with the prevalence of group B2, and resistant to tetracycline, naldixic acid, ampicillin, trimethoprim, neomycin, oxytetracycline and erythromycin encoding the iss virulent gene. A One Health approach is a must to monitor and control E. coli urinary tract infections.

E. coli can be distributed into four major phylogenetic groups (A, B1, B2, and D) based on phylogenetic analysis and subdivided into seven subgroups A0, A1, B1, B2, B3, D1, and D2. The detection of three primers chu A (the outermembrane hemin receptor gene), yjaA (the gene encodes an uncharacterized protein) and TSPE4.C2 (an anonymous DNA fragment) can be done by using a rapid multiplex method for Polymerase Chain Reaction (PCR) based method [3,4]. A study reported that extraintestinal pathogenic strains of groups B2 and D have virulence factors more commonly, while the majority of A and B1 strains are non-pathogenic and isolated from non-diarrheic fecal samples [5,6]. The most common gram-negative pathogen in humans, Escherichia coli is of particular concern because shows multidrug resistance, and their resistance genes are easily transferable to other strains. Such resistance can spread through fecal contamination of surface water, wetlands, river water, and even drinking water [7...

The presence of multidrug-resistant bacteria has been proposed as an environmental impact indicator of wastewater use in agricultural soils. Nevertheless, the effect of untreated wastewater discharge on occurrence and persistence of these type of bacteria in soils is unclear. In this study, multidrug-resistant bacteria and microbial indicators of fecal contamination (coliforms and Salmonella) were determined at different depths (0-15, 15-30 and 30-50 cm), in active agricultural soils under different untreated wastewater irrigation pattern (a zone with past and present wastewater irrigation; a zone with wastewater irrigation until 2003; and a zone that had never been irrigated with wastewater) in Chihuahua, Mexico. A total of 94 multidrug-resistant strains were recovered from all tested soil samples, even from those that have never been irrigated with wastewater. Higher presence (P < 0.05) of multidrug-resistant bacteria was found in soils currently irrigated with untreated wastewater than in soils that has not been irrigated with wastewater for more than 10 years; the later had presence of multidrug-resistant bacteria that was statistically higher than soils that had never been irrigated with wastewater. Wastewater irrigation showed an impact on proliferation of antibiotic-resistant Gram negative bacteria in soils actually irrigated but not in Gram positive bacteria. No statistical difference was found for coliforms and Salmonella between the three soil groups. The effect of depth in multidrug-resistance bacteria presence was negligible. Although multidrug-resistant bacteria was also isolate from soils without wastewater irrigation, their persistence in a highest number in soils irrigated with wastewater suggest that use of untreated wastewater for irrigation enhance the proliferation of multidrug-resistant microorganisms which can be monitoring in soils even after a long period of time after the last irrigation.

The presence of multidrug-resistant bacteria has been proposed as an environmental impact indicator of wastewater use in agricultural soils. Nevertheless, the effect of untreated wastewater discharge on occurrence and persistence of these type of bacteria in soils is unclear. In this study, multidrug-resistant bacteria and microbial indicators of fecal contamination (coliforms and Salmonella) were determined at different depths (0-15, 15-30 and 30-50 cm), in active agricultural soils under different untreated wastewater irrigation pattern (a zone with past and present wastewater irrigation; a zone with wastewater irrigation until 2003; and a zone that had never been irrigated with wastewater) in Chihuahua, Mexico. A total of 94 multidrug-resistant strains were recovered from all tested soil samples, even from those that have never been irrigated with wastewater. Higher presence (P < 0.05) of multidrug-resistant bacteria was found in soils currently irrigated with untreated wastewater than in soils that has not been irrigated with wastewater for more than 10 years; the later had presence of multidrug-resistant bacteria that was statistically higher than soils that had never been irrigated with wastewater. Wastewater irrigation showed an impact on proliferation of antibiotic-resistant Gram negative bacteria in soils actually irrigated but not in Gram positive bacteria. No statistical difference was found for coliforms and Salmonella between the three soil groups. The effect of depth in multidrug-resistance bacteria presence was negligible. Although multidrug-resistant bacteria was also isolate from soils without wastewater irrigation, their persistence in a highest number in soils irrigated with wastewater suggest that use of untreated wastewater for irrigation enhance the proliferation of multidrug-resistant microorganisms which can be monitoring in soils even after a long period of time after the last irrigation.

The presence of ciprofloxacin resistance commensal Escherichia coli (C-R-Ec) was determined for goats in the absence of selective pressure in Northern and Central Greece. The C-R-Ec was categorized in 3 groups with respect to their phenotypic resistance to other antibiotics as well as the carriage of antibiotic resistance genes. The first group consisted of 7 C-R-Ec that were found also resistant to tetracycline. Among them tet(B) (n = 7), qnr(S) (n = 7), and qnr(B) (n = 3) producers were identified by polymerase chain reaction. The second group consisted of 10 C-R-Ec that were found sensitive to all other antibiotics, and their phenotypic resistance to ciprofloxacin was not attributed to the presence of resistance genes. Finally, the third group consisted of 2 C-R-Ec also resistant to sulfamethoxazole. These strains were not carrying any transferable elements that contribute to resistance either to ciprofloxacin or to sulfamethoxazole. This is the first report of ciprofloxacin-resistant E. coli isolated from goats in Greece.

Escherichia coli has been the leading model organism for many decades. It is a fundamental player in modern biology, facilitating the molecular biology revolution of the last century. The acceptance of E. coli as model organism is predicated primarily on the study of one E. coli lineage; E. coli K-12. However, the antecedents of today's laboratory strains have undergone extensive mutagenesis to create genetically tractable offspring but which resulted in loss of several genetic traits. We wished to determine whether these genetic lesions altered the physiology of E. coli such that observations made for E. coli K-12 were not reflective of the true physiology of the species. Here we have repaired the wbbL locus, restoring the ability of E. coli K-12 strain MG1655 to express the O antigen on its cell surface. We demonstrate that O-antigen production results in drastic alterations of many phenotypes and the density of the O antigen is critical for the observed phenotypes. Importantly, the presence of the O antigen enables laboratory strains of E. coli to enter the gut of the Caenorhabditis elegans nematode worm and to kill C. elegans at rates similar to pathogenic bacterial species. We show that killing is associated with bacterial resistance to mechanical shear and persistence in the C. elegans gut. We demonstrate C. elegans killing is a feature of other commensal E. coli and that killing occurs at the same rate as known pathogens. These results suggest C. elegans is not an effective model of human infectious disease.

The aim of this study was to detect and characterize pathogenic and antibiotic resistant Escherichia coli isolated from slaughterhouse wastewater and the effluents of a municipal wastewater treatment plant (WWTP) in Dakar, Senegal. Genetic markers associated with enterohemorrhagic E. coli (EHEC) and extraintestinal pathogenic E. coli (ExPEC) were screened in 268 E. coli isolates from slaughterhouse and 272 E. coli isolates from WWTP. Concerning antimicrobial resistance, 40 E. coli isolates were studied for each of the two sampling sites. None of the E. coli isolates harboring the genes associated with EHEC was detected in WWTP. Of the 13 tested virulence genes, fuyA and f17 were the most prevalent. The pathogenic and resistant E. coli was found in the raw wastewater and the influent of slaughterhouse. The final rejection used for urban gardening, including the watering of vegetables does not contain E. coli. These results showed that, after treatment, the sanitation risks associated with the reuse water from WWTP were low.

Antibiotic selection pressure and genetic associations may lead to the cooccurrence of resistance and virulence in individual pathogens. However, there is a lack of rigorous epidemiological evidence that demonstrates the cooccurrence of resistance and virulence at the population level. Using samples from a population-based case-control study in 25 villages in rural Ecuador, we characterized resistance to 12 antibiotics among pathogenic ( n = 86) and commensal ( n = 761) Escherichia coli isolates, classified by the presence or absence of known diarrheagenic virulence factor genes. The prevalences of resistance to single and multiple antibiotics were significantly higher for pathogenic isolates than for commensal isolates. Using a generalized estimating equation, antibiotic resistance was independently associated with virulence factor carriage, case status, and antibiotic use (for these respective factors: odds ratio [OR] = 3.0, with a 95% confidence interval [CI] of 1.7 to 5.1; OR = ...

Objective: This study aimed to determine prevalence, antimicrobial susceptibility profile and the genetic basis to antimicrobial resistance, targeting blaTEM gene expression of diarrheagenic Escherichia coli among patients suffering from gastroenteritis in Kitale County Referral Hospital. Methods: A cross-sectional study design was adopted. A total of 103 fecal specimens were collected from participants ranging in age from two weeks to 82 years. E. coli was isolated and identified based on phenotypic and biochemical properties. Antimicrobial susceptibility was determined by Kirby-Bauer disk diffusion method. Polymerase chain reaction was used to detect the presence of blaTEM gene. Results: The prevalence of E. coli was 90.2% and age of the patient explained 53% of variation in prevalence. Isolates of diarrheagenic E. coli showed varied degree of susceptibility with sulfamethoxazole at 97%, co-trimoxazole 96%, ampicillin 84%, chloramphenicol 27%, tetracycline 16%, kanamycin 10% and s...

Diarrheagenic Escherichia coli (DEC) are often disseminated through the fecal matter of livestock and waste products including slurry and manure. The study aimed to characterize archived DEC recovered from cattle fecal matter, manure and slurry for quinolone resistance and extended spectrum beta-lactamases (ESBLs) with focus on trends in antimicrobial susceptibility patterns. The susceptibility of the bacteria was tested using standard laboratory procedures. Polymerase chain reaction (PCR) was carried out to detect the presence of qnrA, qnrB, qnrS genes and β-lactamase producing genes (blaESBL) such us blaTEM and blaSHV. About 91% of DEC strains were multidrug resistant (MDR) with non-susceptibility to ≥1 agent in ≥3 antimicrobial classes. The most common resistance was to amoxicillin-clavulanic acid (96.36%), followed by tretacycline (89.09%), ceftazidime (76.36%), and cefotaxime (70.780%). qnrS (18.2%) was the most prevalent quinolone resistant genes, followed by qnrB (7.2%) and q...

This study aimed at verifying the possibility of implementing Performance-Focused Activity-Based Costing system (PFABC) for costing and performance measurement in Al-Rasheed Bank/ Al-Seef Branch by preparing a special model for this purpose. That's to indicate whether it will generate more useful cost information than that provided by Uniform Accounting System used in the bank under study. It was conducted practically through the utilization of data and financial statements of (2020).
The study found a set of conclusions, the most important of which are: (1) The (PFABC) system provides more useful cost information than Al-Rasheed Bank/ Al-Seef Branch's existent system because of its ability to determine the actual and planned costs for each activity separately, which in turn will compute variances and taking corrective actions. Hence, there will be integrated cost information for each activity to help costing and performance measurement in a more reliability and accurately manner; (2) The (PFABC) system cannot be implemented in Al-Rasheed Bank - Al-Seef Branch due to lack of staff and computers resources, lack of advanced information technology, and insufficient experience and knowledge of bank's accountants and other staff to implement such a system.

The isolation and screening of antibiotic resistance strains from three samples sites present in and around hospital of Patna resulted in isolation of 300 bacterial isolates. Out of which maximum number of isolates were obtained from site B while site A gave least number of isolates. 89 bacterial strains showed antibiotic resistance. Among these 89 isolates Site B had maximum number of antibiotic resistant isolates (51) followed by site C with 33 isolates. Among the four groups of antibiotic selected for investigation, the isolates showed highest antibiotic resistance against fluoroquinolones with 1, 20 and 14 isolates from site A, site B and site C respectively showing antibiotic resistance. Site B isolates showed significant resistance against group III (aminoglycosides) antibiotic. Site C isolates also showed maximum resistance against Group IV antibiotics followed by Group II, III and Group I. Site A sample showed resistance against Ciprofloxacin, however it showed sensitivity a...

Background: In many parts of the world, health problems and diseases have often been caused by discharging untreated or inadequately treated wastewater. In this study, we aimed to control physico-chemical parameters in wastewater samples. Also, microbiological analyses were done to reveal Salmonella strains and each Escherichia coli (E.coli) pathotype. Findings: Sixty wastewater samples were collected from fifteen different regions of Tunisia. All physico-chemical parameters (pH, residual free chlorine, total suspended solids, biological oxygen demand, and chemical oxygen demand) were evaluated. For microbiological analyses, samples were filtered to concentrate bacteria. DNA was extracted by boiling and subjected to polymerase chain reaction (PCR) using different pairs of primers. The mean pH values recorded for the sampling point were above the WHO pH tolerance limit. The total suspended solids (TSS) concentrations varied between 240 mg/L and 733 mg/L in entrance points and between 13 mg/L and 76 mg/L in exit points. In entrance points, the studied wastewater has an average COD concentration that varied between 795 mg/mL to 1420 mg/mL. Whereas, BOD concentration of the wastewater ranged between 270 mg/L to 610 mg/L. In exit points, COD concentration varied between 59 mg/L and 141 mg/L, whereas BOD concentration ranged from 15 mg/L to 87 mg/L. The bacteriological control of wastewaters showed that, in entrance points, Escherichia coli (E.coli) was detected at the rate of 76.6%. Three E.coli pathotypes were found: ETEC (53.3%), EAEC (16.6%) and EIEC (6.6%). Concerning the ETEC isolated strains, 8 of 16 (50%) have only the heat-labile toxin gene, 5 of 16 (31.2%) present only the heat-stable toxin gene and 3 of 16 (18.7%) of strains possess both heat-labile toxin gene and heat-stable toxin gene. In exist point, the same pathotypes were found but all detected ETEC strains present only the "est" gene. Concerning Salmonella isolated strains; percentages of 66.6% and 20% were found in entrance and exit points respectively. Conclusions: Wastewaters contain a large amount of pathogenic bacteria that present a real impact on human health. Assessment wastewater treatment stations have to consider in account enterobacterial pathogens as potential pathogens that should be correctly controlled.

Objective: This study aimed to determine prevalence, antimicrobial susceptibility profile and the genetic basis to antimicrobial resistance, targeting blaTEM gene expression of diarrheagenic Escherichia coli among patients suffering from gastroenteritis in Kitale County Referral Hospital. Methods: A cross-sectional study design was adopted. A total of 103 fecal specimens were collected from participants ranging in age from two weeks to 82 years. E. coli was isolated and identified based on phenotypic and biochemical properties. Antimicrobial susceptibility was determined by Kirby-Bauer disk diffusion method. Polymerase chain reaction was used to detect the presence of blaTEM gene. Results: The prevalence of E. coli was 90.2% and age of the patient explained 53% of variation in prevalence. Isolates of diarrheagenic E. coli showed varied degree of susceptibility with sulfamethoxazole at 97%, co-trimoxazole 96%, ampicillin 84%, chloramphenicol 27%, tetracycline 16%, kanamycin 10% and s...

Background: In many parts of the world, health problems and diseases have often been caused by discharging untreated or inadequately treated wastewater. In this study, we aimed to control physico-chemical parameters in wastewater samples. Also, microbiological analyses were done to reveal Salmonella strains and each Escherichia coli (E.coli) pathotype. Findings: Sixty wastewater samples were collected from fifteen different regions of Tunisia. All physico-chemical parameters (pH, residual free chlorine, total suspended solids, biological oxygen demand, and chemical oxygen demand) were evaluated. For microbiological analyses, samples were filtered to concentrate bacteria. DNA was extracted by boiling and subjected to polymerase chain reaction (PCR) using different pairs of primers. The mean pH values recorded for the sampling point were above the WHO pH tolerance limit. The total suspended solids (TSS) concentrations varied between 240 mg/L and 733 mg/L in entrance points and between 13 mg/L and 76 mg/L in exit points. In entrance points, the studied wastewater has an average COD concentration that varied between 795 mg/mL to 1420 mg/mL. Whereas, BOD concentration of the wastewater ranged between 270 mg/L to 610 mg/L. In exit points, COD concentration varied between 59 mg/L and 141 mg/L, whereas BOD concentration ranged from 15 mg/L to 87 mg/L. The bacteriological control of wastewaters showed that, in entrance points, Escherichia coli (E.coli) was detected at the rate of 76.6%. Three E.coli pathotypes were found: ETEC (53.3%), EAEC (16.6%) and EIEC (6.6%). Concerning the ETEC isolated strains, 8 of 16 (50%) have only the heat-labile toxin gene, 5 of 16 (31.2%) present only the heat-stable toxin gene and 3 of 16 (18.7%) of strains possess both heat-labile toxin gene and heat-stable toxin gene. In exist point, the same pathotypes were found but all detected ETEC strains present only the "est" gene. Concerning Salmonella isolated strains; percentages of 66.6% and 20% were found in entrance and exit points respectively. Conclusions: Wastewaters contain a large amount of pathogenic bacteria that present a real impact on human health. Assessment wastewater treatment stations have to consider in account enterobacterial pathogens as potential pathogens that should be correctly controlled.

Among the diseases which etiopathogenesis is associated with Escherichia coli, acute diarrhea stands out. Studies on the characterization of the antimicrobial susceptibility profile contribute to the selection of appropriate empirical antimicrobial therapy. In this study, the antimicrobial susceptibility profile of 98 enterotoxigenic E. coli (ETEC) and enteropathogenic E. coli (EPEC) strains isolated from fecal specimens of children with acute diarrhea was evaluated. The resistance rates to ampicillin, sulfamethoxazole/trimethoprim, amoxicillin/ clavulanate, and nalidixic acid were high, ranging from 34.7% to 10.2%. The result of this research recommends the use of cefotaxime and ceftriaxone for the empirical treatment of children with acute diarrhea which the etiology suggested is ETEC or EPEC.

Fluoroquinolone antibiotics (FQs) have been used worldwide for chemotherapy, animal husbandry, and aquaculture, and the occurrence of FQ-resistant (FQs r) bacteria in natural environments has been reported. Plasmid-mediated transferable quinolone resistance (PMQR) genes are suspected to originate from the chromosomes of water-dwelling bacteria. However, the occurrence of and the potential reservoir of FQs r bacteria and PMQR genes in aquatic environments have not been elucidated. In this study, we detected FQs r bacteria and PMQR genes in aquatic environments in Thailand and Vietnam, and measured FQ contamination. Levels of contamination were greater Thailand (avg. 5130, max 46100 ng L −1) than in Vietnam (avg. 235, max 1130 ng L −1); however, the occurrence of FQs r bacteria was higher in Vietnam (~15%) than in Thailand (~7.0%), suggesting that contamination by FQs is not directly linked to the development of FQs r bacteria. Diverse taxonomic groups of FQs r-bacteria were identified, and one of the PMQR genes, qnrB, was detected from bacteria of environmental origin, not enteric bacteria. This suggests that the environmental bacteria are a potential reservoir of antibiotic resistance determinants even at un-contaminated sites.

Southeast Asia has become the center of rapid industrial development and economic growth. However, this growth has far outpaced investment in public infrastructure, leading to the unregulated release of many pollutants, including wastewater-related contaminants such as antibiotics. Antibiotics are of major concern because they can easily be released into the environment from numerous sources, and can subsequently induce development of antibiotic-resistant bacteria. Recent studies have shown that for some categories of drugs this source-to-environment antibiotic resistance relationship is more complex. This review summarizes current understanding regarding the presence of quinolones, sulfonamides, and tetracyclines in aquatic environments of Indochina and the prevalence of bacteria resistant to them. Several noteworthy findings are discussed: (1) quinolone contamination and the occurrence of quinolone resistance are not correlated; (2) occurrence of the sul sulfonamide resistance gene varies geographically; and (3) microbial diversity might be related to the rate of oxytetracycline resistance.

Contamination of surface waters in developing countries is a great concern. Treated and untreated wastewaters have been discharged into rivers and streams, leading to possible waterborne infection outbreaks and may represent a significant dissemination mechanism of antibiotic resistance genes. In this study, the water quality of San Pedro River, the main river and pluvial collector of the Aguascalientes State, Mexico was assessed. Thirty sample locations were tested throughout the River. The main physicochemical parameters of water were evaluated. Results showed high levels of fecal pollution as well as inorganic and organic matter abundant enough to support the heterotrophic growth of microorganisms. These results indicate poor water quality in samples from different locations. One hundred and fifty Escherichia coli were collected and screened by PCR for several virulence genes. Isolates were classified as either pathogenic (n = 91) or commensal (n = 59). The disc diffusion method ...