scholarly journals Review of Methods Suitable for Environmental Surveillance of Salmonella Typhi and Paratyphi

2020 ◽  
Vol 71 (Supplement_2) ◽  
pp. S79-S83
Author(s):  
Graciela Matrajt ◽  
Lorraine Lillis ◽  
J Scott Meschke
Keyword(s):  
Drinking Water ◽  
Surface Waters ◽  
Environmental Samples ◽  
Salmonella Typhi ◽  
Environmental Surveillance ◽  
Enteric Disease ◽  
Grab Sampling ◽  
Population Prevalence ◽  
Clinical Surveillance ◽  
Sampling Approach

Abstract Typhoid fever is an enteric disease caused by the pathogens Salmonella Typhi and Salmonella Paratyphi. Clinical surveillance networks are lacking in many affected areas, thus presenting a need to understand transmission and population prevalence. Environmental surveillance (ES) has been suggested as a potentially effective method in the absence of (or in supplement to) clinical surveillance. This review summarizes methods identified in the literature for sampling and detection of typhoidal Salmonella from environmental samples including drinking water, wastewater, irrigation water, and surface waters. Methods described use a trap or grab sampling approach combined with various selective culture and molecular methods. The level to which the performance of identified methods is characterized for ES in the literature is variable, thus arguing for the optimization and standardization of ES techniques.

A method for prioritization of areas for pesticides surveillance on surface waters: a study in Minas Gerais, Brazil

2008 ◽  
Vol 57 (11) ◽  
pp. 1693-1698 ◽  
Author(s):  
C. T. Menezes ◽  
L. Heller
Keyword(s):  
Developing Countries ◽  
Quality Control ◽  
Drinking Water ◽  
Surface Water ◽  
Surface Waters ◽  
Multicriteria Analysis ◽  
Legal Issues ◽  
Environmental Surveillance ◽  
Health Authorities ◽  
The World

The occurrence of pesticides in drinking water is a matter of growing concern in several parts of the world, mainly in developing countries, due the possible adverse effects on human health. Pesticides applied in the agriculture are an important source of contamination and are rarely monitored in surface water in developing countries, either by water supply operators or health authorities, often not accomplishing the legal issues regarding the quality control of raw waters. The paper discusses a method for prioritization of surveillance actions of pesticides in surface waters, through multicriteria analysis. Five criteria were defined and a range of weight was established for each criterion. For validation of the method, it was applied in five sub-basins of Grande River Basin—MG. This application allowed ordering priority sub-basins for pesticides surveillance, suggesting two sub-basins as priorities. The validation performed enabled the evaluation and adjustment of the method, mainly regarding the availability of information. The method showed a practical alternative for the environmental surveillance, targeting priority areas. Moreover, its structure allows the application in other different areas and for other pollutants.

The presence of Giardia and Cryptosporidium in surface waters and effluents in Israel

1997 ◽  
Vol 35 (11-12) ◽  
pp. 381-384 ◽  
Author(s):  
U. Zuckerman ◽  
D. Gold ◽  
G. Shelef ◽  
R. Armon
Keyword(s):  
Public Health ◽  
Drinking Water ◽  
Surface Waters ◽  
Environmental Samples ◽  
Health Hazard ◽  
Water Reservoir ◽  
Domestic Sewage ◽  
Average Concentration ◽  
High Concentration ◽  
Drinking Water Reservoir

During a period of 9 months (May 1995-January 1996), various environmental sources were investigated for the presence of Giardia and Cryptosporidium in Israel. Out of 15 samples from five streams, 12 were positive for Cryptosporidium (80%) with an average concentration of 0.04–1.9 oocysts/l and 8 were positive for Giardia (53.3%) with 0.05–0.78 cysts/l. Two springs were also tested and found positive for Cryptosporidium and (0.54 oocysts/l) only. The main drinking water reservoir of Israel, Lake Kineret, was also sampled 6 times at two sites. Cryptosporidium was isolated in 4/6 samples (66.6%) at an average concentration of 0.3–1.09 oocysts/l while Giardia was present in 5/6 samples (83.3%), 0.135–16.2 cysts/l. Drinking water entering a filtration pilot plant was also tested and found positive for Cryptosporidium in 23/35 samples (0–317 oocysts/l) and 8/35 for Giardia (0–16.7 cysts/l). In order to evaluate some potential inputs of contamination of the drinking water sources, two possible contributors were tested: domestic sewage and cowshed effluents. In sewage effluents, 3/3 samples were positive for both Cryptosporidium and Giardia. The oocysts and cysts were present at 8.3–8.05/l and 5–27.3/l respectively. In cowshed effluents, 1/6 samples was positive for Cryptosporidium at a high concentration (3,630 oocysts/l) but no Giardia cysts were found. The levels of Cryptosporidium and Giardia oocysts and cysts isolated from these environmental samples may present a public health hazard although no major outbreaks have so far been reported in Israel.

Habitat Association of Klebsiella Species

1985 ◽  
Vol 6 (2) ◽  
pp. 52-58 ◽  
Author(s):  
Susan T. Bagley
Keyword(s):  
Drinking Water ◽  
Gastrointestinal Tract ◽  
Surface Waters ◽  
Industrial Effluents ◽  
Opportunistic Pathogen ◽  
Habitat Associations ◽  
Habitat Association ◽  
Klebsiella Species ◽  
Almost All ◽  
Polluted Waters

AbstractThe genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that “K. pneumoniae” actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae—humans, animals, sewage, and polluted waters and soils; K. oxytoca—frequent association with most habitats; K. terrigena— unpolluted surface waters and soils, drinking water, and vegetation; K. planticola—sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis—infrequently detected (primarily with humans).

Water Treatment Considerations–Aquatic Humus

1983 ◽  
Vol 15 (S2) ◽  
pp. 95-101 ◽  
Author(s):  
E T Gjessing
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Humic Substances ◽  
Health Effects ◽  
Surface Waters ◽  
Cold Climate ◽  
Treatment Processes ◽  
Aquatic Humus ◽  
Treatment Considerations

For several reasons the surface waters in cold climate areas are coloured due to humic substances. There are two major objections against humus in drinking water, the first is concerned with aesthetical and practical problems and the second is due to indirect negative health effects. There are essentially three different methods in use today for the removal or reduction of humus colour in water: (1) Addition of chemicals with the intention of reducing the “solubility”, (2) Addition of chemicals in order to bleach or mineralize the humus, and (3) Filtration with the intention of removal of coloured particles and some of the “soluble” colour. The treatment processes are discussed.

A Nude Mouse Model as an in vivo Infectivity Assay for Cryptospomdiosis

1993 ◽  
Vol 27 (3-4) ◽  
pp. 65-68 ◽  
Author(s):  
B. H. Kwa ◽  
M. Moyad ◽  
M. A. Pentella ◽  
J. B. Rose
Keyword(s):  
Drinking Water ◽  
Mouse Model ◽  
Nude Mouse ◽  
Cryptosporidium Parvum ◽  
Nude Mice ◽  
Surface Waters ◽  
Nude Mouse Model ◽  
Infectivity Assay ◽  
Limiting Dilution

Cryptosporidium parvum is an important patliogen of diarrlieal disease which has been implicated in several outbreaks associated with contamination of surface waters. In monitoring for C. parvum in drinking water sources, it is important to asce tain the viability, and more importantly, the infectivity of low numbers of recovered oocysts. Groups of 10 Balb/C nude (nu/nu) mice, 4-8 weeks old at time of inoculation, were infected with C. parvum oocysts from naturally infected calves and purified using Sheather's sucrose gradients. Oocysts were counted using the Merifluor IFA kit (Meridian). Each group of 10 mice were infected with 1,10,100 and 1000 oocysts respectively. Numbers of oocysts per inoculation were determined by limiting dilution, and parallel inocula were counted microscopically to ascertain the accuracy of the dilutions. Two uninfected nude mice were kept in each cage to serve as controls. Mouse stools were collected every 4 days, concentrated using the Fekal Kontrate Concentration Kit (Meridian) and oocysts were counted with a UV microscope using the Merifluor IFA Kit (Meridian). Oocyst counts were expressed in terms of number of oocyst/g feces. Mice inoculated with 1000 oocysts began to shed oocysts on day 32, mice inoculated with 100 oocysts began to shed on days 44-48, mice inoculated with 10 oocysts began to shed on days 56-60, and mice inoculated with 1 oocyst shed on days 68-88. All infected mice continued to shed oocysts intermittently and with variable oocyst counts until day 180 when the experiment was terminated. This study established that it is possible to infect nude mice with very low numbers, down to a single oocyst. We are currently in the process of correlating the nude mouse assay with other viability assays.

Viruses and Water: Problems, Detection, and Control

1993 ◽  
Vol 27 (7-8) ◽  
pp. 127-133 ◽  
Author(s):  
H. Dizer ◽  
J. Dürkop ◽  
A. Grohmann ◽  
H. Kopecka ◽  
J. M. López-Pila
Keyword(s):  
Drinking Water ◽  
Surface Waters ◽  
Membrane Filtration ◽  
Wastewater Treatment Plants ◽  
Health Hazard ◽  
Primary Source ◽  
Detection Methods ◽  
Secondary Effluent ◽  
Naturally Occurring ◽  
Water Problems

Secondary effluent of wastewater treatment plants contains a high number of viruses and other pathogens, which pose a health risk to the population, (especially when receiv ng waters are used for bathing and swimming, or for growing shellfish. In areas with a high density of population, where drinking water supply is dependent on surface waters and contaminated rivers are the primary source of drinking water, failure of the filtration or of the disinfection step, or of any other “barriers” supposed to warrant safe potable water, will increase the risk of health hazard for the consumer. We have compared the efficiency of viral elimination in secondary effluent by flocculation, uv rradiation and membrane filtration taking naturally occurring, or additionally seeded f2 phages, as indicator for viruses. Flocculation decreased the number of phages present in secondary effluent by more than two logs. If combined with uv irradiation, the elimination reached five additional logs. Membrane filtration eliminated essentially all naturally occurring phages. Improvement of the quality of surface waters calls for a refinement of detection methods for viruses. We have found that the polymerase chain reaction (PCR) might be used for detecting viruses in surface waters.

Bank filtration: a suitable process for the removal of iodinated X-ray contrast media?

2004 ◽  
Vol 50 (5) ◽  
pp. 261-268 ◽  
Author(s):  
S. Schittko ◽  
A. Putschew ◽  
M. Jekel
Keyword(s):  
Drinking Water ◽  
Contrast Media ◽  
Surface Waters ◽  
Sampling Period ◽  
Transformation Products ◽  
Bank Filtration ◽  
Anoxic Conditions ◽  
X Ray ◽  
High Concentrations ◽  
Media Concentration

After bank filtration, effluent influenced surface waters are often used as raw drinking water. It is known that high concentrations of iodinated X-ray contrast media are detectable in such surface waters and thus, more knowledge about the behaviour of the contrast media during bank filtration is necessary and the subject of investigations in this study. The adsorbable organic iodine (AOI), four widely used iodinated X-ray contrast media and four possible transformation products were quantified in an influenced lake, five groundwater wells and a drinking water well. Under anoxic conditions the AOI as well as the concentration of the contrast media are decreased by bank filtration, whereby the AOI is decreased by 64% and the contrast media concentration can be reduced up to 95%, depending on the compound. In the raw drinking water the following average concentrations were determined: Iopromid <20 ng/L, Diatrizote 166 ng/L, Iopamidol 166 ng/L and Iohexol 34 ng/L. Instationary conditions during the sampling period indicate that, at least under anoxic conditions, a large part of the contrast media and transformation products, which are still iodinated, may be associated to colloids and/or humic material.

scholarly journals Identification and management of microbial contaminations in a surface drinking water source

2007 ◽  
Vol 5 (S1) ◽  
pp. 67-79 ◽  
Author(s):  
J. Åström ◽  
T. J. R. Pettersson ◽  
T. A. Stenström
Keyword(s):  
Drinking Water ◽  
Water Intake ◽  
Surface Waters ◽  
Microbial Contamination ◽  
Water Source ◽  
Drinking Water Source ◽  
Raw Water ◽  
Indicator Organisms ◽  
E Coli ◽  
The City

Microbial contamination of surface waters constitutes a health risk for drinking water consumers which may be lowered by closing the raw water intake. We have evaluated microbial discharge events reported in the river Göta älv, which is used for raw water supply to the city of Göteborg. Elevated levels of faecal indicator bacteria were observed during periods of closed raw water intake. High bacteria levels were, however, also occasionally detected during periods of open intake, probably as a result of microbial discharge far upstream in the river which may be difficult to predict and manage by closing the intake. Accumulated upstream precipitations, resulting in surface runoff and wastewater contaminations in the catchment, correlated positively with the levels of total coliforms, E. coli, intestinal enterococci and sulfite-reducing clostridia. Levels of faecal indicator organisms were negatively correlated to the water temperature due to enhanced survival at lower temperatures. Wastewater discharges from a municipality located just upstream of the water intake resulted in elevated E. coli concentrations downstream at the raw water intake for Göteborg. To improve the prediction of microbial contaminations within the river Göta älv, monitoring data on turbidity and upstream precipitation are of particular importance.

scholarly journals Seasonal Dynamics in the Number and Composition of Coliform Bacteria in Drinking Water Reservoirs

2021 ◽  
Author(s):  
Carolin Reitter ◽  
Heike Petzoldt ◽  
Andreas Korth ◽  
Felix Schwab ◽  
Claudia Stange ◽  
...  
Keyword(s):  
Climate Change ◽  
Drinking Water ◽  
Microbial Community ◽  
Water Temperature ◽  
Surface Waters ◽  
Coliform Bacteria ◽  
List Type ◽  
Water Production ◽  
Water Reservoirs ◽  
Drinking Water Production

AbstractWorldwide, surface waters like lakes and reservoirs are one of the major sources for drinking water production, especially in regions with water scarcity. In the last decades, they have undergone significant changes due to climate change. This includes not only an increase of the water temperature but also microbiological changes. In recent years, increased numbers of coliform bacteria have been observed in these surface waters. In our monitoring study we analyzed two drinking water reservoirs (Klingenberg and Kleine Kinzig Reservoir) over a two-year period in 2018 and 2019. We detected high numbers of coliform bacteria up to 2.4 x 104 bacteria per 100 ml during summer months, representing an increase of four orders of magnitude compared to winter. Diversity decreased to one or two species that dominated the entire water body, namely Enterobacter asburiae and Lelliottia spp., depending on the reservoir. Interestingly, the same, very closely related strains have been found in several reservoirs from different regions. Fecal indicator bacteria Escherichia coli and enterococci could only be detected in low concentrations. Furthermore, fecal marker genes were not detected in the reservoir, indicating that high concentrations of coliform bacteria were not due to fecal contamination. Microbial community revealed Frankiales and Burkholderiales as dominant orders. Enterobacterales, however, only had a frequency of 0.04% within the microbial community, which is not significantly affected by the extreme change in coliform bacteria number. Redundancy analysis revealed water temperature, oxygen as well as nutrients and metals (phosphate, manganese) as factors affecting the dominant species. We conclude that this sudden increase of coliform bacteria is an autochthonic process that can be considered as a mass proliferation or “coliform bloom” within the reservoir. It is correlated to higher water temperatures in summer and is therefore expected to occur more frequently in the near future, challenging drinking water production.HighlightsColiform bacteria proliferate in drinking water reservoirs to values above 104 per 100 mlThe genera Lelliottia and Enterobacter can form these “coliform blooms”Mass proliferation is an autochthonic process, not related to fecal contaminationsIt is related to water temperature and appears mainly in summerIt is expected to occur more often in future due to climate changeGraphical abstract

scholarly journals Nanomaterials Based Drinking Water Purification: Comparative Study with a Conventional Water Purification Process

2018 ◽  
Vol 63 (1) ◽  
pp. 96-112 ◽  
Author(s):  
Barış Şimşek ◽  
İnci Sevgili ◽  
Özge Bildi Ceran ◽  
Haluk Korucu ◽  
Osman Nuri Şara
Keyword(s):  
Silver Nanoparticles ◽  
Drinking Water ◽  
Graphene Oxide ◽  
Water Treatment ◽  
Water Purification ◽  
Drinking Water Treatment ◽  
Treatment Method ◽  
Salmonella Typhi ◽  
Liquid Ratio ◽  
Solid Liquid

One of the ways of fully securing the presence of fresh water is water treatment process. Nanomaterials and nanotechnology offers an innovative solution for water treatment. In this study, physical, chemical and microbiological improvement rates of raw water were analyzed after filtration with graphene oxide. Graphene oxide's water treatment performance; silver nanoparticles, silver nanoparticles & graphene oxide composites that are commonly used in water treatment were compared with a traditional treatment method. When compared to the traditional method, there were improvements of 50 %, 40.7 %, 86.8 % and 45.5 % for color, TIC, TOC and hardness properties, respectively in water treatment by GO-based filtration with solid liquid ratio of 0.7 % (v/v). In water treatment with GO-Ag based filtration, 39.8 %, 69.8 %, 10.3 % and 28.6 % of improvements were obtained for TIC, TOC, hardness and LSI value compared to the conventional method. Both GO at 0.7 % (v/v) solid-liquid ratio and GO-Ag nanocomposites were successful in the number of total viable microorganisms and inhibiting microorganisms such as Escherichia coli fecal (gaita-infected), Salmonella typhi, Enterococcus faecalis, Pseudomona aeruginosa and Staphylococcus aureus. Among the studied parameters GO-Ag nanocomposites found to be the most suitable for drinking water treatment.

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