scholarly journals Impact of Some Ecological Factors on Fecal Contamination of Drinking Water by Diarrheagenic Antibiotic-ResistantEscherichia coliin Zagazig City, Egypt

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Ahmed Elsadek Fakhr ◽  
Maha Kamal Gohar ◽  
Amal Hassan Atta

Fecal contamination of drinking water is a major health problem which accounts for many cases of diarrhea mainly in infants and foreigners. This contamination is a complex interaction of many parameters. Antibiotic resistance among bacterial isolates complicates the problem. The study was done to identify fecal contamination of drinking water by Diarrheagenic Antibiotic-ResistantEscherichia coliin Zagazig city and to trace reasons for such contamination, three hundred potable water samples were investigated forE. coliexistence. Locations ofE. colipositive samples were investigated in relation to population density, water source, and type of water pipe. SixteenE. colistrains were isolated. Antibiotic sensitivity was done and enterotoxigenic, enteropathogenic, and enterohaemorrhagic virulence genes were investigated by PCR. Probability of fecal contamination correlated with higher population density, with increased distance from Zagazig water plant, and with asbestos cement water pipes. Resistance to at least one antimicrobial drug was found in all isolates. Virulence genes were detected in a rate of 26.27%, 13.13%, 20%, 6.67%, and 33.33% for LT, ST, stx1, stx2, and eae genes, respectively. This relatively high frequency of fecal contamination points towards the high risk of developing diarrhea by antibiotic resistant DEC in low socioeconomic communities particularly with old fashion distribution systems.

2019 ◽  
Vol 13 (1) ◽  
pp. 171-176
Author(s):  
Samson Girma ◽  
Zelalem Yaregal ◽  
Yosef Beyene ◽  
Mengistu Tadesse ◽  
Desalegn Addise ◽  
...  

Background: The decline in microbial quality of drinking water may be attributed to many factors among which the presence of biofilm within the distribution system is the major cause of contamination. Drinking water distribution systems provide an oligotrophic environment, for post-treatment recovery and regrowth of microorganisms including the opportunistic Nontuberculosis Mycobacterium (NTM). Objective: The aim was to look for opportunistic non tuberculosis mycobacterium and indicator organisms of fecal contamination from biofilm in drinking water distribution pipeline from selected sites of Addis Ababa. Materials and Methods: A total of 40 biofilm samples were collected from two sub-cities of Addis Ababa. Biofilm samples were taken from the inner surfaces of the get valve and water meter. For the detection of E. coli and E. faecalis, diluted biofilm samples were filtered, then it was incubated on respective culture media. For non-tuberculosis mycobacterium, the homogenized biofilm sediment was processed using the standard SD bio line method, whereby, The processed sediment was inoculated to appropriate solid and liquid culture media. The DNA extraction was conducted by chemical lysis followed by PCR amplification, from the grown colonies on LJ media (Löwenstein–Jensen). The identification of Mycobacterium species was performed by reverse hybridization using a membrane strip and an enzymatic color reaction. Results: From the total biofilm samples, 14 out of 40 (35%) were positive for mycobacteria species. M. gordonea was the most prevalent specie of Mycobacterium, whereby 8/14 (57.1%) of the isolates were from this species followed by M. fortuitum 1/14 (7.14%). About (35.7%) 5/14 of the genus Mycobaterium were unidentified species. Indicator organisms of fecal contamination (E. coli and E. faecalis) were found in 3/40(7.5%) and 6/40(15%) respectively. There was no statistically significant association between nontuberculosis mycobacterium and the indicator organisms at p value of 0.01. Conclusion: The study has highlighted that the occurrence of NTM in drinking water distribution in a significant proportion. M. gordonae was found to be the most dominant species of nontuberculosis mycobacterium found in the distribution line biofilm samples.


2011 ◽  
Vol 1 (4) ◽  
pp. 233-237
Author(s):  
A. O. Ajayi ◽  
N. F. Agangan

In present investigation, the bacteriological analysis and antibiotic sensitivitypattern of drinking water samples collected from different sources ofAkungba Ã¢â‚¬ÂAkoko, Nigeria was done. The antibiotics mainly considered in ourstudy for determining the sensitivity were amongst the commonly used inthis area for treatment of infectious diseases. As a result, the bacteriologicalindex, especially coliform count was observed notably high with 72 x10 1 cfu/ml for stream sample and 26.4 x 10 1 cfu/ml for borehole sample. The majorbacterial isolates identified in the water samples were Staphylococcus sp,E.coli  Ã¢â‚¬Ânegative bacteria wereobserved showing 75% and 65% resistant to Septrin and Amoxicillin respectively.Also, multiple drug resistance was observed for many antibiotics.Therefore, the presence of high amount antibiotic resistant bacteria of clinicalimportance is reported in these water sources which are usually consumedby students and members of the University community. Hence, thisstudy necessitates the need for water treatment so that epidemics of waterbornebacterial disease can be averted in this region., Klebsiella sp, Pseudomonas sp., Enterococcus sp., Bacillus cereus andothers. With regards to the antibiotic sensitivity test, all isolates showed100% resistance to Ampicillin and Cloxacillin and 85.7% resistance to Zinnacef[a cephalosporin product]. However, the gram 


2017 ◽  
Vol 83 (6) ◽  
Author(s):  
James R. Johnson ◽  
Stephen B. Porter ◽  
Brian Johnston ◽  
Paul Thuras ◽  
Sarah Clock ◽  
...  

ABSTRACT Chicken meat products are hypothesized to be vehicles for transmitting antimicrobial-resistant and extraintestinal pathogenic Escherichia coli (ExPEC) to consumers. To reassess this hypothesis in the current era of heightened concerns about antimicrobial use in food animals, we analyzed 175 chicken-source E. coli isolates from a 2013 Consumer Reports national survey. Isolates were screened by PCR for ExPEC-defining virulence genes. The 25 ExPEC isolates (12% of 175) and a 2:1 randomly selected set of 50 non-ExPEC isolates were assessed for their phylogenetic/clonal backgrounds and virulence genotypes for comparison with their resistance profiles and the claims on the retail packaging label (“organic,” “no antibiotics,” and “natural”). Compared with the findings for non-ExPEC isolates, the group of ExPEC isolates had a higher prevalence of phylogroup B2 isolates (44% versus 4%; P < 0.001) and a lower prevalence of phylogroup A isolates (4% versus 30%; P = 0.001), a higher prevalence of multiple individual virulence genes, higher virulence scores (median, 11 [range, 4 to 16] versus 8 [range, 1 to 14]; P = 0.001), and higher resistance scores (median, 4 [range, 0 to 8] versus 3 [range, 0 to 10]; P < 0.001). All five isolates of sequence type 131 (ST131) were ExPEC (P = 0.003), were as extensively resistant as the other isolates tested, and had higher virulence scores than the other isolates tested (median, 12 [range, 11 to 13] versus 8 [range, 1 to 16]; P = 0.005). Organic labeling predicted lower resistance scores (median, 2 [range, 0 to 3] versus 4 [range, 0 to 10]; P = 0.008) but no difference in ExPEC status or virulence scores. These findings document a persisting reservoir of extensively antimicrobial-resistant ExPEC isolates, including isolates from ST131, in retail chicken products in the United States, suggesting a potential public health threat. IMPORTANCE We found that among Escherichia coli isolates from retail chicken meat products purchased across the United States in 2013 (many of these isolates being extensively antibiotic resistant), a minority had genetic profiles suggesting an ability to cause extraintestinal infections in humans, such as urinary tract infection, implying a risk of foodborne disease. Although isolates from products labeled “organic” were less extensively antibiotic resistant than other isolates, they did not appear to be less virulent. These findings suggest that retail chicken products in the United States, even if they are labeled “organic,” pose a potential health threat to consumers because they are contaminated with extensively antibiotic-resistant and, presumably, virulent E. coli isolates.


1995 ◽  
Vol 31 (5-6) ◽  
pp. 123-129 ◽  
Author(s):  
Rami Pedahzur ◽  
Ovadia Lev ◽  
Badri Fattal ◽  
Hillel I. Shuval

The inactivation efficiencies of silver ions, hydrogen peroxide and their combination was studied as part of a performance evaluation of the combined disinfectant for drinking water applications. The major advantages of such combined disinfectant include, low toxicity of its components, long lasting residual effect and low disinfection by product formation. Specific strains of E. coli (E. coli-B (SR-9) and E. coli K-12) were used in this study as target microorganisms and the separate and combined inactivation efficiencies of silver and hydrogen peroxide were evaluated at different concentrations and exposure durations. Both, silver and hydrogen peroxide exhibited a significant inactivation performance even at concentrations that do not pose any health risk according to the EEC, WHO and the USEPA (the USEPA Maximum Contaminant Level (MCL) of silver is 90 ppb, and currently, there is no MCL for hydrogen peroxide but it is approved as a food additive in the USA). Combinations of 1:1000 silver:hydrogen peroxide (w) exhibited higher inactivation performance as compared with each of the disinfectants alone and in some cases a synergistic effect was observed, i.e., the combined disinfectant exhibited higher inactivation performance than the sum of the inactivation levels of the separate disinfectants. Thus, for example, one hour exposure to 30 ppb silver, 30 ppm hydrogen peroxide and their combination yielded 2.87, 0.65 and 5 logs of inactivation respectively. While the rate of inactivation shown by this combined disinfectant, now available commercially in a stabilized formulation is relatively slow, it may well hold promise as a secondary disinfectant providing long lasting residuals and biofilm control required for distribution systems. Its disinfection action may be similar to chloramines, the use of which has been recently outlawed in France and in Germany and which are now under careful scrutiny in other countries due to the formation of undesirable by-products.


2014 ◽  
Vol 81 (5) ◽  
pp. 1788-1798 ◽  
Author(s):  
Abhirosh Chandran ◽  
Asit Mazumder

ABSTRACTEscherichia coliisolates (n= 658) obtained from drinking water intakes of Comox Lake (2011 to 2013) were screened for the following virulence genes (VGs):stx1andstx2(Shiga toxin-producingE. coli[STEC]),eaeand the adherence factor (EAF) gene (enteropathogenicE. coli[EPEC]), heat-stable (ST) enterotoxin (variants STh and STp) and heat-labile enterotoxin (LT) genes (enterotoxigenicE. coli[ETEC]), andipaH(enteroinvasiveE. coli[EIEC]). The only genes detected wereeaeandstx2, which were carried by 37.69% (n= 248) of the isolates. Onlyeaewas harbored by 26.74% (n= 176) of the isolates, representing potential atypical EPEC strains, while onlystx2was detected in 10.33% (n= 68) of the isolates, indicating potential STEC strains. Moreover, four isolates were positive for both thestx2andeaegenes, representing potential EHEC strains. The prevalence of VGs (eaeorstx2) was significantly (P< 0.0001) higher in the fall season, and multiple genes (eaeplusstx2) were detected only in fall. Repetitive element palindromic PCR (rep-PCR) fingerprint analysis of 658E. coliisolates identified 335 unique fingerprints, with an overall Shannon diversity (H′) index of 3.653. Diversity varied among seasons over the years, with relatively higher diversity during fall. Multivariate analysis of variance (MANOVA) revealed that the majority of the fingerprints showed a tendency to cluster according to year, season, and month. Taken together, the results indicated that the diversity and population structure ofE. colifluctuate on a temporal scale, reflecting the presence of diverse host sources and their behavior over time in the watershed. Furthermore, the occurrence of potentially pathogenicE. colistrains in the drinking water intakes highlights the risk to human health associated with direct and indirect consumption of untreated surface water.


2021 ◽  
Vol 6 (4) ◽  
pp. 181
Author(s):  
Jannatul Ferdous ◽  
Ridwan Bin Rashid ◽  
Rebeca Sultana ◽  
Sabera Saima ◽  
Musharrat Jahan Prima ◽  
...  

This study aimed to investigate the origin of diverse pathotypes of E. coli, isolated from communal water sources and from the actual drinking water vessel at the point-of-drinking inside households in a low-income urban community in Arichpur, Dhaka, Bangladesh, using a polymerase chain reaction (PCR). Forty-six percent (57/125, CI 95%: 41−58) of the isolates in the point-of-drinking water and 53% (55/103, CI 95%: 45−64) of the isolates in the source water were diarrheagenic E. coli. Among the pathotypes, enterotoxigenic E. coli (ETEC) was the most common, 81% (46/57) of ETEC was found in the point-of-drinking water and 87% (48/55) was found in the communal source water. Phylogenetic group B1, which is predominant in animals, was the most frequently found isolate in both the point-of-drinking water (50%, 91/181) and in the source (50%, 89/180) water. The phylogenetic subgroup B23, usually of human origin, was more common in the point-of-drinking water (65%, 13/20) than in the source water (35%, 7/20). Our findings suggest that non-human mammals and birds played a vital role in fecal contamination for both the source and point-of-drinking water. Addressing human sanitation without a consideration of fecal contamination from livestock sources will not be enough to prevent drinking-water contamination and thus will persist as a greater contributor to diarrheal pathogens.


2019 ◽  
Author(s):  
Amy J. Pickering ◽  
Jenna Swarthout ◽  
MaryAnne Mureithi ◽  
John Mboya ◽  
Benjamin F. Arnold ◽  
...  

AbstractCombined water, sanitation, and handwashing (WSH) interventions have the potential to reduce fecal pathogens along more transmission pathways than single interventions alone. We measured Escherichia coli levels in 3909 drinking water samples, 2691 child hand rinses, and 2422 toy ball rinses collected from households enrolled in a two-year cluster-randomized controlled trial evaluating single and combined WSH interventions. Water treatment alone reduced E. coli in drinking water, while a combined WSH intervention improved water quality by the same magnitude but did not affect levels of fecal indicator bacteria on child hands or toy balls. The failure of the WSH interventions to reduce E. coli along important child exposure pathways is consistent with the lack of a protective effect from the interventions on child diarrhea or child growth during the trial. Our results have important implications for WSH program design; the sanitation and handwashing interventions implemented in this trial should not be expected to reduce child exposure to fecal contamination in other similar settings.


2021 ◽  
Vol 99 (12) ◽  
pp. 1353-1359
Author(s):  
Angelika V. Zagainova ◽  
Galina M. Trukhina ◽  
Yury A. Rakhmanin ◽  
Tamara Z. Artemova ◽  
Marina A. Sukhina

Introduction. The increasing bacterial contamination of water bodies requires an increase in water quality control’s reliability to ensure epidemic safety against waterborne infections. Therefore, researchers in both Russia and Europe came to the conclusion that it is necessary to search for indicator microorganisms that can more accurately suggest the presence of pathogens. microorganisms in water than traditional indicators. The aim of the study was to justify the introduction of indicator indices of fecal contamination “generalized coliform bacteria” and Escherichia coli to assess the safety of drinking water Material and methods. The article provides an analysis of domestic and international regulatory documents and literary materials regulating the quality of drinking water in terms of sanitary and microbiological indicators and assessment criteria. The results of many years of experimental and field research carried out by research organizations and practical organizations of the Federal Service for Supervision of Consumer Rights Protection and Human Welfare are presented. Results. On the territory of Russia, “general coliform bacteria,” is one of the indicator indices chosen according to the fermentation of lactose, determine the safety of drinking water. The water does not take into account pathogenic bacteria (Salmonella, Shigella) and a number of lactose-negative opportunistic bacteria, causative agents of intestinal infections. The study of microorganisms isolated from the feces of patients confirms the frequency of occurrence of lactose-negative microorganisms to varying from 20 to 100% of strains. With an annual trend towards a decrease in the percentage of non-standard drinking water samples in terms of microbiological indices, general intestinal infections (GII) of unknown etiology increase, i.e. risk of GII. If the quality of drinking water does not correspond to thermotolerant coliform bacteria (TCB), 95% of samples contain E. coli. Therefore, the determination of E. coli more reliably indicates the intake of fresh fecal contamination and provides efficiency in taking measures to eliminate an unfavorable situation than TCB. Conclusion. Reasons are given for the introduction of more reliable microbiological indicators of water safety control, such as - “generalized coliform bacteria” with the preservation of the abbreviation GCB, combining both lactose-positive and lactose-negative bacteria, determined by the sign of glucose fermentation, negative oxidase test and negative stain according to Gram and E. coli as an indicator of recent faecal contamination, which will allow the assessment of water quality for a wide range of bacteria of the order Enterobacterials, corresponding to the modern taxonomy of Enterobacteriaceae NCBI, will ensure harmonization with international requirements and the safety of drinking water for the population.


Author(s):  
Farhan Mohammad Khan ◽  
Rajiv Gupta

Escherichia coli or E. coli is a member of the fecal coliform group and is a more specific indicator of fecal contamination than other fecal coliform species, its presence indicate possibly presence of harmful bacteria which will cause diseases and it also suggests the extent as well as the nature of the contaminants. E. coli bacteria able to survive in water for 4 &ndash; 12 weeks and at present, it appears as an indicator to provide the accurate bacterial contamination of fecal matter in drinking water, because of the availability of simple, affordable, fast, sensitive and exact detection techniques. According to the laboratory experiment based techniques, 24 - 48 hours are required for the bacterial concentration to be reported. So, there is a necessity for continuous monitoring. Techniques for detection of many pathogenic bacterial strains are not yet available, sometimes days to weeks are required to get the results. To overcome the difficulties, expensive and time-consuming techniques are required to detect, count and identify the presence of specific bacterial strain. Public health relies on online monitoring of water quality that depends majorly on examination of fecal indicator bacteria, thus protection of health requires fecal pollution indicator so that it is not required to analyze drinking water to overcome the problems associated with waterborne diseases. This paper will brief the classification, sources, survival of E. coli bacteria and its correlation with basic water quality parameters in water sources.```


2014 ◽  
Vol 15 (1&2) ◽  
pp. 99-107
Author(s):  
G.V Zodape

14 drinking water samples were collected from Vile Parle to Dadar of Suburban’s of (P-South ward offices of B.M.C (Bombay Municipal Corporation) Mumbai in the month from June to December 2012. The samples of drinking-water were analyzed for Cu, Zn, Mn, Fe, As, Cr, Ni, Pb, Cd and Hg. From the results so obtained, the contamination due to heavy metals – Zn (3.115 ppm and 7.816 ppm), Mn (3.115 ppm and 7.426 ppm), Fe (1.124 ppm and 2.872 ppm), As (0.011 ppm to 0.091 ppm), Cr (0.188 ppm and 0.998 ppm ), Pb (1.587 ppm and 4.56 ppm) and Cd (0.011 ppm and 0.051 ppm ) was found to be high whereas the contamination due to Cu (0.012 ppm and 0.313 ppm), Ni (0.126 ppm and 0.774 ppm), were found below the acceptable limits and no Hg was detected in the samples of drinking-water. In the present work, MacConkey Broth was used as a differential medium for detection and enumeration of coliforms from a wide variety water samples. The presence of positive doubtful presumptive test immediately suggests that the water is non potable (i.e., both acid and gas develops in a tube after 48 hours incubation). Confirmation suggests that there is fecal contamination in the water under investigation and hence it is non potable. All the fourteen samples (streaked from positive Ma cConkey broth tubes) were found to be contaminated with E. coli, which was further confirmed by the presence of colonies with green metallic sheen observed under a microscope confirmed that the said samples were contaminated with E. coli - the major indicator of fecal contamination.


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