Can routine monitoring of E. coli fully account for peak event concentrations at drinking water intakes in agricultural and urban rivers?

Monitoring the microbiological quality of water used for recreational activities is very important to human public health. Although the sanitary quality of recreational marine waters could be evaluated by standard methods, they are time-consuming and need confirmation. For these reasons, faster and more sensitive methods, such as the defined substrate-based technology, have been developed. In the present work, we have compared the standard method of membrane filtration using Tergitol-TTC agar for total coliforms and Escherichia coli, and Slanetz and Bartley agar for enterococci, and the IDEXX defined substrate technology for these faecal pollution indicators to determine the microbiological quality of natural recreational waters. ISO 17994:2004 standard was used to compare these methods. The IDEXX for total coliforms and E. coli, Colilert®, showed higher values than those obtained by the standard method. Enterolert® test, for the enumeration of enterococci, showed lower values when compared with the standard method. It may be concluded that more studies to evaluate the precision and accuracy of the rapid tests are required in order to apply them for routine monitoring of marine and freshwater recreational bathing areas. The main advantages of these methods are that they are more specific, feasible and simpler than the standard methodology.

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Bacteria Detection and Differentiation Using Impedance Flow Cytometry

Sensors ◽

10.3390/s18103496 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3496 ◽

Cited By ~ 21

Author(s):

Casper Clausen ◽

Maria Dimaki ◽

Christian Bertelsen ◽

Gustav Skands ◽

Romen Rodriguez-Trujillo ◽

...

Keyword(s):

Drinking Water ◽

Real Time ◽

Electrical Response ◽

Solid Particles ◽

Electrical Impedance Spectroscopy ◽

Contaminated Water ◽

E Coli ◽

Two Samples ◽

Microbiological Control ◽

Frequency Phase

Monitoring of bacteria concentrations is of great importance in drinking water management. Continuous real-time monitoring enables better microbiological control of the water and helps prevent contaminated water from reaching the households. We have developed a microfluidic sensor with the potential to accurately assess bacteria levels in drinking water in real-time. Multi frequency electrical impedance spectroscopy is used to monitor a liquid sample, while it is continuously passed through the sensor. We investigate three aspects of this sensor: First we show that the sensor is able to differentiate Escherichia coli (Gram-negative) bacteria from solid particles (polystyrene beads) based on an electrical response in the high frequency phase and individually enumerate the two samples. Next, we demonstrate the sensor’s ability to measure the bacteria concentration by comparing the results to those obtained by the traditional CFU counting method. Last, we show the sensor’s potential to distinguish between different bacteria types by detecting different signatures for S. aureus and E. coli mixed in the same sample. Our investigations show that the sensor has the potential to be extremely effective at detecting sudden bacterial contaminations found in drinking water, and eventually also identify them.

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Drinking water and diarrhoeal disease due to Escherichia coli

Journal of Water and Health ◽

10.2166/wh.2003.0008 ◽

2003 ◽

Vol 1 (2) ◽

pp. 65-72 ◽

Cited By ~ 49

Author(s):

Paul R. Hunter

Keyword(s):

Escherichia Coli ◽

Drinking Water ◽

Clinical Presentation ◽

Diarrhoeal Disease ◽

Central Place ◽

E Coli ◽

Related Disease ◽

Direct Damage ◽

Water Microbiology

Escherichia coli has had a central place in water microbiology for decades as an indicator of faecal pollution. It is only relatively recently that the role of E. coli as pathogen, rather than indicator, in drinking water has begun to be stressed. Interest in the role of E. coli as a cause of diarrhoeal disease has increased because of the emergence of E. coli O157:H7 and other enterohaemorrhagic E. coli, due to the severity of the related disease. There are enterotoxigenic, enteropathogenic, enterohaemorrhagic, enteroinvasive, enteroaggregative and diffusely adherent strains of E. coli. Each type of E. coli causes diarrhoeal disease through different mechanisms and each causes a different clinical presentation. Several of the types cause diarrhoea by the elaboration of one or more toxins, others by some other form of direct damage to epithelial cells. This paper discusses each of these types in turn and also describes their epidemiology, with particular reference to whether they are waterborne or not.

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Spread of Antibiotic Resistance in Aquatic Environments: E. coli as a Case Study

Proceedings ◽

10.3390/proceedings2110693 ◽

2018 ◽

Vol 2 (11) ◽

pp. 693 ◽

Cited By ~ 1

Author(s):

Maria Adamantia Efstratiou ◽

Marina Bountouni ◽

Efthimios Kefalas

Keyword(s):

Escherichia Coli ◽

Drinking Water ◽

Antibiotic Resistance ◽

Rural Communities ◽

Ground Water ◽

Aquatic Environments ◽

Multiple Resistance ◽

E Coli ◽

Of Greece

The aim of this study was to gather information on the spread of antibiotic resistance in Escherichia coli isolates from wells, boreholes and untreated drinking water in islands of Greece. We analyzed for antibiotic resistance 235 E. coli strains isolated from untreated drinking water of small rural communities, and ground water from 4 islands. Resistance was tested against Norfloxacin, Ciprofloxacin, Levofloxacin, Amoxicillin and Cefaclor. More than half (54.9%) were resistant to at least one of the antibiotics tested. Of these 26.3% showed multiple resistance (to two or more antibiotics). Strains from drinking water sources were overall more sensitive. Frequent resistance was observed for Amoxicillin (38.3%) and Levofloxacin (28.5%), low for Norfloxacin (5.5%).

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