scholarly journals The rationale for introducing the indices «Generalized coliform bacteria» and «Escherichia coli» into the scheme of sanitary and microbiological control of water quality as indices of fecal contamination

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 – 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.```


2020 ◽  
Vol 23 ◽  
Author(s):  
Mariana Amabile Waideman ◽  
Vivian Plaça Teixeira ◽  
Elisa Hizuru Uemura ◽  
Tânia Montenegro Stamford ◽  
Diego Averaldo Guiguet Leal ◽  
...  

Abstract The study evaluated the drinking water quality from 45 public schools in the city of Curitiba, Brazil. Water samples were harvested from two different points at each school: the first one, drinking fountain used by students (n=45) and the second, kitchen faucet (n=45), comprising 90 samples. The samples were submitted to analysis according to current legislation, such as: dosage of free chlorine; colony counts of heterotrophic bacteria; presence of total coliform bacteria and Escherichia coli. In addition, an enterococci analysis was also included as a complementary microbiological indicator of fecal contamination. The isolated strains of enterococci were identified and submitted to an antibiotic susceptibility test. In relation to the legal parameters, 35.5% (n=16) of the 45 schools evaluated did not meet the quality water standards set by the Brazilian legislation. Although none of the 90 samples exhibited the presence Escherichia coli, 6.6% (n=6) of the analyzed samples presented enterococci contamination. Regarding the antibiotic susceptibility test, the isolated strains demonstrated a similar behavior, became resistant to six antibiotics and had intermediate sensitivity to one (Streptomycin) of the nine antibiotics tested. The drinking water destined for human consumption in the public schools may pose health risks for students since the fecal contamination by enterococci was confirmed, and it could be observed that the water may be a source of genes from bacteria resistant to antimicrobials. This study reinforces the importance of monitoring complementary microbiological indicators to assure water quality, seeing that fecal contamination was detected only when alternative parameters were inserted, emphasizing the relevance of including microbiological indicators beyond what the legislation requires to evaluate the drinking water more effectively and to safeguard public health.


2015 ◽  
Vol 54 (3) ◽  
pp. 194-203
Author(s):  
Eva Grilc ◽  
Ivanka Gale ◽  
Aleš Veršič ◽  
Tina Žagar ◽  
Maja Sočan

Abstract Introduction. Even brief episodes of fecal contamination of drinking water can lead directly to illness in the consumers. In water-borne outbreaks, the connection between poor microbial water quality and disease can be quickly identified. The impact of non-compliant drinking water samples due to E. coli taken for regular monitoring on the incidence of notified acute gastrointestinal infections has not yet been studied. Methods. The objective of this study was to analyse the geographical distribution of notified acute gastrointestinal infections (AGI) in Slovenia in 2010, with hotspot identification. The second aim of the study was to correlate the fecal contamination of water supply system on the settlement level with the distribution of notified AGI cases. Spatial analysis using geo-information technology and other methods were used. Results. Hot spots with the highest proportion of notified AGI cases were mainly identified in areas with small supply zones. The risk for getting AGI was drinking water contaminated with E. coli from supply zones with 50-1000 users: RR was 1.25 and significantly greater than one (p-value less than 0.001). Conclusion. This study showed the correlation between the frequency of notified AGI cases and noncompliant results in drinking water monitoring.


Author(s):  
Azwar Azwar ◽  
Safrida Safrida ◽  
Yarmaliza Yarmaliza ◽  
Fitrah Reynaldi ◽  
Arfah Husna

The quality of drinking water supply must be guaranteed. The WHO (World Health Organization) determines water quality by means of E. Coli bacteria. Based on the Minister of Health Regulation No. 492 / MENKES / PER / IV / 2010 The maximum permissible content of E. Coli in drinking water is 0 per 100 ml. The presence of E. coli in water is an indicator of human and animal fecal pollution that can cause diarrhea and even death. Selection of Refillable Drinking Water (AMIU) as an alternative to fulfill drinking water needs is a risk that can endanger health if the quality of AMIU is added if consumers do not pay attention to safety and hygiene. This study aims to see the content of E. coli in Refill Drinking Water (AMIU) in Samatiga District, West Aceh Regency. This research is experimental with cross sectional design using quantitative laboratory examination with the Most Probable Number (MPN) method. The population in this study were all refill drinking water depots that did not have a drinking certificate in Samatiga District, West Aceh Regency. The research sample used a total sampling method of 7 refill drinking water depots. The results of the analysis showed that from all samples as many as 6 samples (85.71%) tested positive for Escherichia coli bacteria and 1 sample (14.29%) tested negative for Escherichia coli bacteria. Based on the calculation of the number of colonies with the MPN / 100 ml table then comparing with the requirements of the Regulation of the Minister of Health of the Republic of Indonesia Number 492 / Menkes / Per / IV / 2010 concerning drinking water quality requirements that the 6 samples tested positive were not suitable for consumption.


2019 ◽  
Vol 2 (2) ◽  
pp. a13-19
Author(s):  
ELEXSON NILLIAN ◽  
AMIZA NUR ◽  
DIYANA NUR ◽  
AMIRAH ZAKIRAH ◽  
GRACE BEBEY

Contamination of drinks with E. coli O157:H7 served in food premises such as restaurants can cause haemorrhagic colitis and haemolytic uremic syndrome to humans. The presence or absence of faecal pathogen was demonstrated using coliform group as indicator microorganisms. Therefore, this study was conducted to detect the presence of E. coli O157:H7 in drinking water from food restaurant premise in Kota Samarahan and Kuching to ensure safe and potable drinking water is served to the consumer. A total of thirty (n=30) drink samples including six types of each of the samples are cold plain water, iced tea, iced milo, syrup and iced milk tea. Most Probable Number (MPN) procedure was used in this study to enumerate the MPN values of coliform bacteria in each drink collected. A total of 53.33% (16/30) of the drink samples showed positive E. coli detection. Then, the PCR assay showed 6.25% (one out of 16 isolates) samples were positive and carried stx1 gene produced by E. coli O157:H7 in iced milo sample types. This study showed the drinks collected from food premises was contaminated with faecal contamination, which was not safe to drink by the consumer. Therefore, preventive actions should be taken to prevent foodborne illness outbreak in future


2021 ◽  
Vol 909 (1) ◽  
pp. 012006
Author(s):  
Efadeswarni ◽  
F Y Amandita ◽  
N Puspandari ◽  
N Aini

Abstract The water quality of the Sunter River in Jakarta was classified as heavily polluted due to activities around the river, both domestic and non-domestic. As one of the environmental parameters for water quality, the presence of Escherichia coli (E. coli) is normally found any natural environment, and under certain conditions it can become resistant to antimicrobials due to genetic mutations. The mutated E. coli produces Extended Spectrum Beta-Lactamase (ESBL) enzymes and has a higher survival ability in antibiotic-contaminated river water, thus potentially endangering public health. This study was aimed to evaluate the effect of environmental factors on the abundance of ESBL producing E. coli and their resistance to antibiotic cefotaxime. Sampling was conducted in six locations representing the upstreams and the downstreams of Sunter River, following the Global Surveillance guidelines. E. coli strains were isolated using Tryptone Bile X-glucuronide (TBX) agar medium (with and without the addition of cefotaxime 4μg/ml) and the antibiotic sensitivity test of ESBL E. coli was conducted by performing a double-disk test. The results showed that the highest average abundance of ESBL E. coli was found in the sample taken from Sindang Station (904.24 x 104 colony per unit (CFU) / 100 mL) and the lowest was from Sunter Station (1,58 x 104 CFU / 100 mL). The results of the Bivariate Pearson correlation analysis showed that temperature, pH, and salinity were negatively correlated with the abundance of ESBL-producing E. coli bacteria.


Author(s):  
Francesca Rubino ◽  
Yahaira Corona ◽  
José Guadalupe Jiménez Pérez ◽  
Charlotte D. Smith

In many regions where drinking water supply is intermittent and unreliable, households adapt by storing water in cisterns or rooftop tanks. Both intermittent supply and stored water can be vulnerable to contamination by microorganisms with deleterious health effects. The Guadalajara Metropolitan Area is a rapidly growing urban center with over five million residents where household storage is nearly ubiquitous. This pilot study was conducted in July 2018 to examine the microbiological quality of drinking water in Guadalajara. Samples were tested for free available chlorine residual, total coliform bacteria, and E. coli. A survey on access to water and public perspectives was also conducted. Water exiting rooftop tanks exceeded regulatory limits for total coliform levels in half of the homes studied. Piped water arriving at two homes had total coliform levels that far exceeded regulatory limits. No E. coli were detected in any of the samples. Only 35% of homes had a chlorine residual between the recommended 0.2 and 1.5 mg/L. Many homes reported unpleasant odors and colors. Only 7% of residents drank the piped water. Future studies are needed, especially during April and May when many homes reported a higher disruption to water service.


2018 ◽  
Vol 12 (09) ◽  
pp. 700-705
Author(s):  
Mojtaba Bonyadian ◽  
Hamdallah Moshtaghi ◽  
Hanie Nadi

Introduction: The quality of drinking water has an important role in human health. This study was aimed to detect Escherichia. coli, Salmonella sp. and Vibrio cholerae from bottled drinking waters produced in Iran. Methodology: A total of 240 samples of bottled water of different brands were collected for testing between March 2015 to December 2015 in Shahrekord-Iran. Samples were examined by polymerase chain reaction (PCR) combined with culture methods for the detection of E. coli, Salmonella sp., and V. cholerae. Results: The results of PCR revealed that the uidA gene from E. coli, IpaB gene from Salmonella sp, and epsM gene from V. cholerae were detected in 6 (2.5%), 1 (0.4 %), 0 (0%) of the samples, respectively. But in culture methods, only E. coli 5 (2.1%) were isolated from the samples. The contamination with E. coli was significantly higher (P < 0.05) in water produced during the hot seasons than the cold seasons. Conclusions: This study confirmed the presence of Escherichia coli as the main microorganism in bottle drinking water in Iran. Also, our study showed that PCR can be used as a screening method for monitoring the enteric pathogens in drinking water.


Author(s):  
Francesca Rubino ◽  
Yahaira Corona ◽  
José Guadalupe Jiménez Pérez ◽  
Charlotte Smith

In many regions where drinking water supply is intermittent and unreliable, households adapt by storing water in cisterns or rooftop tanks. Both intermittent supply and stored water can be vulnerable to contamination by microorganisms with deleterious health effects. The Metropolitan Zone of Guadalajara is a rapidly growing urban center with over five million residents where household storage is nearly ubiquitous. This pilot study was conducted in July 2018 to examine the microbiological quality of drinking water in Guadalajara. Samples were tested for free available chlorine residual, total coliform bacteria, and Escherichia coli. A survey on access to water and public perspectives was also conducted. Water exiting rooftop tanks exceeded regulatory limits for total coliform levels in half of the homes studied. Piped water arriving at two homes had total coliform levels that far exceeded regulatory limits. No E. coli were detected in any of the samples. Only 35% of homes had a chlorine residual between the recommended 0.2 and 1.5 mg/L. Many homes reported unpleasant odors and colors. Only 7% of residents drank the piped water. Future studies are needed, especially during April and May when many homes reported a higher disruption to water service.


2000 ◽  
Vol 124 (3) ◽  
pp. 417-425 ◽  
Author(s):  
M. RUTTER ◽  
G. L. NICHOLS ◽  
A. SWAN ◽  
J. DE LOUVOIS

Results from statutory testing of private water supplies in nine Public Health Laboratories in England were compiled, and the effects of supply class, source, treatment and location on water quality were examined. A total of 6551 samples from 2911 supplies was examined, over a 2-year period, of which 1342 (21%) samples, and 949 (33%) supplies on at least one occasion, failed current regulations for Escherichia coli. Total coliforms, including E. coli, were detected in 1751 (27%) samples from 1215 (42%) supplies. The percentage of samples positive for E. coli was highest in summer and autumn, and lowest in winter. Samples taken from larger supplies and from boreholes were less frequently contaminated than those from other sources. Chlorination, filtration or UV light treatment improved the bacteriological quality of supplies, but still resulted in a low level of compliance with the regulations. The public health implications of the study are discussed.


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