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).

Back to pre-disinfection of highly polluted waters

2002 ◽  
Vol 2 (3) ◽  
pp. 219-226
Author(s):  
N. Narkis ◽  
A. Katz-Stoller
Keyword(s):  
Drinking Water ◽  
Chlorine Dioxide ◽  
Surface Waters ◽  
Pathogenic Microorganisms ◽  
Organic Substances ◽  
Ammonium Ions ◽  
Chlorine Disinfection ◽  
Main Disadvantage ◽  
Polluted Waters ◽  
By Products

The initial pre-disinfection was one of the stages that most contributed to the formation of a large number of halogenated disinfection by-products (DBPs). The threat and awareness to the formation of chlorine disinfection by-products, refrained from using pre-disinfection with chlorine in the treatment of contaminated raw waters, to be used as drinking water. The main purpose of this research was to study whether chlorine dioxide can be used for pre-disinfection in the treatment of highly polluted wastewaters and surface waters. Chlorine dioxide was found suitable, as a replacement for chlorine, for disinfection of water containing natural organic substances, effluents’ organic materials and ammonium ions, due to its advantages, and especially because it is an effective disinfectant for killing pathogenic microorganisms and destroying viruses. Chlorine dioxide does not form THMs and barely creates chloroorganic compounds. However, the main disadvantage of the chlorine dioxide is the creation of undesirable chlorite and chlorate ions, which are suspected of being toxic. This research showed that the undesirable chlorite ions can be removed completely by adding Fe+2, which reduces ClO2- to the harmless Cl-, and is oxidized to Fe+3, to form the ferric polyhydroxo complexes, that can be used as the flocculant, in the next flocculation step, for the achievement of safer drinking water.

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.

scholarly journals Evidence of Quorum Sensing in Cyanobacteria by Homoserine Lactones: The Origin of Blooms

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1831
Author(s):  
Natalia Herrera ◽  
Fernando Echeverri
Keyword(s):  
Cell Proliferation ◽  
Quorum Sensing ◽  
Microcystis Aeruginosa ◽  
Industrial Effluents ◽  
Cyanobacterial Blooms ◽  
Cylindrospermopsis Raciborskii ◽  
Bacterial Communication ◽  
Homoserine Lactones ◽  
Exogenous Compounds ◽  
Almost All

Although several theories have been postulated to explain cyanobacterial blooms, their biochemical origin has not yet been found. In this work, we explore the existence of bacterial communication, called quorum sensing, in Microcystis aeruginosa and Cylindrospermopsis raciborskii. Thus, the application of several known acylhomoserine lactones to cultures of both cyanobacteria causes profound metabolic. At 72 h post-application, some of them produced substantial increases in cell proliferation, while others were inhibitors. There was a correlation with colony-forming activity for most of them. According to ELISA analysis, the microcystin levels were increased with some lactones. However, there was a clear difference between M. aeruginosa and C. raciborskii culture since, in the first one, there was an inducing effect on cell proliferation, while in C. raciborskii, the effects were minor. Besides, there were compound inhibitors and inducers of microcystins production in M. aeruginosa, but almost all compounds were only inducers of saxitoxin production in C. raciborskii. Moreover, each lactone appears to be involved in a specific quorum sensing process. From these results, the formation of cyanobacterial blooms in dams and reservoirs could be explained since lactones may come from cyanobacteria and other sources as bacterial microflora-associated or exogenous compounds structurally unrelated to lactones, such as drugs, industrial effluents, and agrochemicals.

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.

Prevalence of Colistin resistance among Enterobacteriaceae, A 10-year glance

2021 ◽  
Vol 1 (1) ◽  
pp. 016-024
Author(s):  
Assama Riaz ◽  
Dinali Obeysekera ◽  
Kelsie Ruslow
Keyword(s):  
Healthcare Systems ◽  
Klebsiella Pneumonia ◽  
Unanswered Question ◽  
Colistin Resistance ◽  
Klebsiella Species ◽  
Gram Negative ◽  
The World ◽  
Gram Negative Organisms ◽  
Almost All ◽  
Alternative Antibiotic

Multidrug resistance is a global healthcare problem. Gram-negative organisms, particularly Enterobacteriaceae strains are responsible for almost 60% of nosocomial infections. Colistin acts as the last treatment resort in complicated, critical, and MDR cases; also become resistant in the last few years in an escalating manner. Its resistance has been reported almost all over the world. Since there is no alternative antibiotic of colistin-resistant isolates is available. The last year of 2020 was completely engaged with the Covid-19 pandemic for global healthcare systems. This issue is still persisting with no solution. Strict infection control policies and a noval antibiotic with lesser side effects are great in demand to resolve this issue. We gathered 28 studies from 2010 that reported colistin resistance among Enterobacteriaceae throughout the world. Colistin resistance still reported and escalated globally with no available solution. Asia was the leading region with 50% of selected studies followed by Europe and Klebsiella pneumonia and Klebsiella species were the leading organisms of colistin resistance among Enterobacteriaceae. This mini-review was designed to highlight the global importance of colistin-resistant isolates among Enterobacteriaceae, which still an unanswered question.

scholarly journals Antibiotic Susceptibility Pattern of Bacteria Isolated from an Urban Referral Hospital in Dhaka City

2016 ◽  
Vol 2 (2) ◽  
pp. 7-11
Author(s):  
M Mushfequr Rahman ◽  
J Ashraful Haq ◽  
MAH Golam Morshed ◽  
Farida Huq
Keyword(s):  
Antibiotic Susceptibility ◽  
Referral Hospital ◽  
Dhaka City ◽  
Bacterial Strains ◽  
Klebsiella Species ◽  
Acinetobacter Species ◽  
Pseudomonas Species ◽  
Judicious Choice ◽  
Almost All ◽  
First And Second Generation

The present study was to assess the pattern of antibiotic susceptibility of the isolated bacteria in an urban referral hospital in Dhaka City. A total of 393 bacterial strains were isolated from various specimens over a l0-months period. The majority of the organisms were Escherichia coli Q3.33oh) followed by Klebsiella species (27.480 ), Staphylococcas aureus (l7.Oioh),Lcinetobacter species (8.l4yo), Pseudomonas species (7.l2Yo), and others. The thirdgeneration Cephalosporins Hke Ceftriaxone, Ceftazidime and Cefotaxime were sensitive against 45-66yo isolated Enterobacteriaceae. The first- and second-generation Cephalosporins were less effective. The sensitivity to Ciprofloxacin of various Enterobacteriaceae was only between 33-4Oo compared to 52.8-67.9Vo against Gentamicin. Majority of the Enterobacteriaceae were resistant to Ampicillin, whereas almost all of the Enterobacteriaceae (94-100%o) were sensitive to Imipenem. Ahont97.UY;s Acinetobacter species were susceptible to Imipenem. Sensitivity of the organism (Acinetobacter) to third-generation Cephalosporins ranged between 50-560 , whereas 40.60/o were found sensitive to Ciprofloxacin. The sensitivity to Chloramphenicol, Co-trimoxazole, Cephalexin and Ampicillin ranged between 9.3oh to 34.30 . About 93.0%o of Pseudomonas species were sensitive to Imipenem. The rate of susceptibility to Gentamicin and Netilmicin was higher than those of the Ciprofloxacin and Ceftriaxone (67.80/o and, 53.57o vs, 39.2yo), About 707o of isolated S. aureus were resistant to OxacilHn but all were sensitive to Vancomycin. The result of this study would help the physicians to make a judicious choice of,.anti.biotics for therapeutic purposes.Bangladesh J Med Microbiol 2008; O2 (02):7-ll

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 ANTIBACTERIAL RESISTANCE PATTERN OF PSEUDOMONAS AERUGINOSA ISOLATED FROM CLINICAL SAMPLES AT A GENERAL HOSPITAL IN PADANG, WEST SUMATRA, INDONESIA

2017 ◽  
Vol 10 (8) ◽  
pp. 158
Author(s):  
Rustini Rustini ◽  
Jamsari Jamsari ◽  
Marlina Marlina ◽  
Nasrul Zubir ◽  
Yori Yuliandra
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Bacterial Resistance ◽  
Clinical Sample ◽  
Opportunistic Pathogen ◽  
Positive Control ◽  
Diffusion Method ◽  
Clinical Samples ◽  
Resistance Pattern ◽  
Tract Infections ◽  
Almost All

Objectives: Pseudomonas aeruginosa is an opportunistic pathogen that has an innate resistance to some antibiotics. This bacterium is one of the mostcommon causes of nosocomial infections that include surgical wound infections, burns, and urinary tract infections. The bacteria have been reportedlyresistant to many antibiotics and have developed multidrug resistance (MDR). The objective of the study was to determine the resistance pattern ofP. aeruginosa isolated from clinical samples of patients against some major antibiotics.Methods: Isolates of P. aeruginosa were obtained from clinical sample of urine, sputum, swabs, pus, feces, and blood and cultured in cetrimide agar. P.aeruginosa ATCC 27853 was used as a positive control. The antibacterial susceptibility testing was conducted against 13 antibiotics: Ceftazidime, cefotaxime,ceftriaxone, cefoperazone, ciprofloxacin, levofloxacin, ofloxacin, gentamicin, amikacin, piperacillin, ticarcillin, meropenem, and imipenem. The examinationwas carried out using agar diffusion method of Kirby-Bauer and following the standards from Clinical and Laboratory Standards Institute (CLSI).Results: The results showed that bacterial resistance was established against all tested antibiotics. The highest number of resistance was shownagainst ceftriaxone (44.21%), whereas the most susceptibility was exhibited against amikacin (only 9.47% of resistance). MDR P. aeruginosa (MDRPA)was detected on almost all clinical samples tested, except the feces. The sample with the highest percentage of MDRPA was the pus.Conclusion: The study concludes that the most effective antibiotic against P. aeruginosa is amikacin (91.51%), whereas the most resistance is exhibited to ceftriaxone (43.16%).

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