Download or read book Development of a PCR Based Method to Detect Viable Cryptosporidium Parvum Oocysts from Environmental Water Concentrates written by Debanjana Dasgupta and published by . This book was released on 2003 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of TaqMan Real time PCR for the Detection of Viable Cryptosporidium Parvum Oocysts in Environmental Water Samples written by Melissa A. Cameron and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Cryptosporidium parvum is of growing public health concern due to its ability to survive typical water treatment processes. In order to protect the public from infection, the Environmental Protection Agency developed Method 1623 for the detection of Cryptosporidium oocysts in environmental water samples. Execution of this method is time consuming, and the results do not provide an accurate estimation of viability. Therefore, current research is focused on creating a real-time PCR method for the accurate detection of viable Cryptosporidium parvum in environmental water samples. This thesis presents the development of a real-time PCR method, and the results obtained in its use on field samples. The assay was standardized using multiple dilution series in addition to positive and negative controls. Environmental water samples were tested using this method and Method 1623 for comparison. The results were compared statistically to determine the degree of correlation between methods. The data show that the real-time PCR method correlates well to Method 1623. In addition, the assay was determined to be more cost effective and less labor intensive than Method 1623. Although these early findings are promising, additional research and development are needed before the proposed assay can be used in industry.
Download or read book Advancing Cryptosporidium Parvum Detection Methodologies written by Mark C. Jenkins and published by American Water Works Association. This book was released on 2002 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study focused on ideal methods of detecting C. parvum oocysts which give low detection limits, specific and sensitive detection in concentraded samples, and differentiation of viable from non-viable oocysts; are usable by a water treatment facility and provide quantitative results within a few hours. Potential useful methods are continuous flow centrifugation, rel-time TaqMan PCR, cell culture inoculation followed by PCR of DNA extration, and FISH.
Download or read book Assessment of Cryptosporidium Parvum Oocyst Viability by a Cell Culture based Infectivity Assay written by Mingqi Deng and published by . This book was released on 2000 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cryptosporidium written by Mark S Smith and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cryptosporidium, in its various forms, is a widely recognised cause of outbreaks of waterborne disease. Regulatory bodies worldwide are increasingly requiring the development of "fit-for-purpose" detection methods for this protozoan parasite, but analysis is often problematic. Bringing together international academic and industry-based experts, this book provides a comprehensive review of the current state of analytical techniques for the detection of Cryptosporidium, as well as looking at likely future developments. In particular, the issues of species identification and oocyst viability are addressed. Quality assurance issues and potential problems associated with the new Cryptosporidium regulations are also highlighted. The extent of the perceived problems and the regulatory backdrop against which the analysis must be carried out are also discussed. Scientists in the water industry, environmental testing laboratories, researchers, consultants, environmental health professionals, food manufacturers and regulatory or environmental bodies are amongst the many who should read this book. In addition, anyone with an interest in microbiological challenges and problem-solving will welcome the coverage.
Download or read book Evaluation of Genotyping Techniques for Crytosporidium Parvum written by Paul A. Rochelle and published by American Water Works Association. This book was released on 2001 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: A research teams reports on its efforts to develop and implement DNA fingerprinting techniques to characterize and differentiate the parvus species of protozoal parasite that is ubiquitous in rivers and lakes, is relatively resistant to chlorine disinfection at commonly used concentrations, and can prove fatal for immune compromised people who become infected. They evaluate fingerprinting methods based on polymerase chain reaction, determine which method is most suitable for determining strains or isolates within a species, implement the most appropriate molecular method for determining whether the isolates can be differentiated based on its animal or human host or geographical source, and determine the particular source of the protozoa contamination in source water. The report is not indexed. c. Book News Inc.
Download or read book Cryptosporidium Parvum Oocysts written by Satomi Kato and published by . This book was released on 2001 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparing Cell Culture and Mouse Assays for Measuring Infectivity of Cryptosporidium written by Paul A. Rochelle and published by IWA Publishing. This book was released on 2005-06-30 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cell culture techniques are routinely used for measuring the infectivity of a wide range of human pathogens. A variety of different cell culture systems and detection methodologies have been applied to Cryptosporidium parvum. However, the correlation between cell culture methods and animal infectivity assays has not been thoroughly investigated. Although many cell culture methods have been developed for C. parvum, it has not been proven that infectivity in cell culture is a good indicator of the ability of oocysts to cause infections in animals. The objective of this research was to compare in-vitro cell culture methods with a mouse assay for measuring infectivity of C. parvum oocysts. The specific objectives were to (1) compare the dose response and sensitivity of cell culture and mouse assays with multiple isolates; (2) compare infectivity methods with oocysts exposed to environmental water samples; (3) determine the reproducibility and variability of the methods; and (4) compare cell culture and animal assays for assessing ozone and UV disinfection.For untreated oocysts, challenge doses were enumerated by flow cytometry. Dose response curves were constructed by regression analysis of oocyst dose against a logistic transformation of the proportional infectivity and the 50% infectious doses for each isolate were calculated by solving the regression for a logit value of zero. Infections in CD-1 mice were detected by microscopy following staining with hematoxylin and eosin. Infection in HCT-8 and Caco-2 cells was detected by C. parvum-specific RT-PCR. In MDCK cells, infection was detected using immunofluorescence. For disinfection studies, oocysts were exposed to UV using a medium-pressure, collimated beam apparatus and inactivation was measured as the difference in ID50 of unexposed and UV-exposed oocysts. Oocysts were exposed to ozone using batch, semi-batch, and single continuously stirred tank reactors at 1, 5, and 15°C.This investigation demonstrated that in-vitro cell culture was equivalent with a mouse assay for measuring infectivity of untreated C. parvum oocysts and should therefore be considered a practical alternative for assessing the potential of oocysts to cause infection. However, the high levels of variability displayed by mouse and cell culture methods indicated that infectivity and disinfection experiments should be limited to discerning relatively large differences. Of the three cell culture assays, the HCT-8/RT-PCR method displayed the closest agreement with the CD-1 mouse assay. C. hominis was infectious in HCT-8 cells but did not infect mice. Similar results were obtained with CD-1 mice and HCT-8 cells for measuring infectivity of oocysts that had been exposed to environmental water for 35 days. There was also very good agreement between HCT-8 cell culture and CD-1 mouse assays for measuring UV inactivation of C. parvum. A medium-pressure UV dosage of 5.6 mJ/cm2 resulted in 2-log10 inactivation. The shapes of ozone inactivation curves were generally the same for mouse and cell culture derived data although the CD-1 mouse assay typically generated 0.5 to 1-log10 higher levels of inactivation than HCT-8 cells. In addition, there was a stimulatory response in oocysts exposed to ozone below 20 mg.min/L when assayed by HCT-8 cell culture. Consequently, further research is necessary to understand the response of oocysts to ozone when inactivation is assessed by cell culture methods. The water industry should adopt in-vitro cell culture as a routine method for measuring the infectivity of waterborne C. parvum and C. hominis oocysts. This project has demonstrated that cell culture has equivalency with the standard CD-1 mouse assay and cell culture assays can be applied to oocysts recovered from water using approved methods. However, there needs to be a thorough, robust, and well-controlled study to compare the various cell culture-based assays for measuring C. parvum and C. hominis infectivity. This evaluation should include inter-laboratory comparisons and round-robin testing. Cell culture-based assays should also be used to assess disinfection of C. hominis isolates. Originally published by AwwaRF for its subscribers in 2004. This publication can also be purchased and downloaded via Pay Per View on Water Intelligence Online - click on the Pay Per View icon below
Download or read book Development of a New Method to Detect Cryptosporidium Parvum Oocysts from Water Samples by Using Aluminium Sulphate Flocculation and Immunomagnetic Separation written by Christoph Bissegger and published by . This book was released on 1997 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Detection and Quantification of Cryptosporidium Oocysts in Environmental Samples written by Megha Duggal and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Indicators for Waterborne Pathogens written by National Research Council and published by National Academies Press. This book was released on 2004-06-19 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent and forecasted advances in microbiology, molecular biology, and analytical chemistry have made it timely to reassess the current paradigm of relying predominantly or exclusively on traditional bacterial indicators for all types of waterborne pathogens. Nonetheless, indicator approaches will still be required for the foreseeable future because it is not practical or feasible to monitor for the complete spectrum of microorganisms that may occur in water, and many known pathogens are difficult to detect directly and reliably in water samples. This comprehensive report recommends the development and use of a "tool box" approach by the U.S Environmental Protection Agency and others for assessing microbial water quality in which available indicator organisms (and/or pathogens in some cases) and detection method(s) are matched to the requirements of a particular application. The report further recommends the use of a phased, three-level monitoring framework to support the selection of indicators and indicator approaches.Â
Download or read book Development of an in Situ PCR Assay to Detect Cryptosporidium Oocysts in Environmental Samples written by Stacey E. Chmura and published by . This book was released on 2010 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies on the Survival and Viability Testing of Cryptosporidium Parvum Oocysts in the Water Environment written by and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Manual of Environmental Microbiology written by Cindy H. Nakatsu and published by John Wiley & Sons. This book was released on 2020-08-11 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The single most comprehensive resource for environmental microbiology Environmental microbiology, the study of the roles that microbes play in all planetary environments, is one of the most important areas of scientific research. The Manual of Environmental Microbiology, Fourth Edition, provides comprehensive coverage of this critical and growing field. Thoroughly updated and revised, the Manual is the definitive reference for information on microbes in air, water, and soil and their impact on human health and welfare. Written in accessible, clear prose, the manual covers four broad areas: general methodologies, environmental public health microbiology, microbial ecology, and biodegradation and biotransformation. This wealth of information is divided into 18 sections each containing chapters written by acknowledged topical experts from the international community. Specifically, this new edition of the Manual Contains completely new sections covering microbial risk assessment, quality control, and microbial source tracking Incorporates a summary of the latest methodologies used to study microorganisms in various environments Synthesizes the latest information on the assessment of microbial presence and microbial activity in natural and artificial environments The Manual of Environmental Microbiology is an essential reference for environmental microbiologists, microbial ecologists, and environmental engineers, as well as those interested in human diseases, water and wastewater treatment, and biotechnology.
Download or read book Development and Standardization of a Cryptosporidium Genotyping Tool for Water Samples written by Lihua Xiao and published by American Water Works Association. This book was released on 2006 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: CD-ROM contains data gathered in the research of this study.
Download or read book Waterborne Pathogens written by Emmanuelle Guillot and published by IWA Publishing. This book was released on 2009-11-15 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: Infectious diseases caused by pathogenic bacteria, viruses and protozoa, are the most common and widespread health risk associated with drinking water. Most waterborne pathogens are introduced into drinking water supplies by human or animal faeces (enteric pathogens) but they can also exist naturally in water environments as indigenous aquatic micro-organisms. Controlling the risks related to these pathogens is a permanent challenge for the water industry. In addition to the constantly evolving range of pathogens to consider, assessing and managing such risks requires the integration of information issued by a wide range of disciplines. The necessary knowledge is however still sketchy and incomplete for most pathogens, and research efforts are necessary to fill the remaining gaps of knowledge. The purpose of this study is to provide an updated, comprehensive review of current knowledge on a selection of pathogens of interest for the drinking water industry, and to identify the remaining gaps of knowledge and thus the necessary research to be conducted. Emphasis has been laid on the information needed to assess and manage the risks related to each of these pathogens in drinking water production and distribution. The pathogens considered in this review were selected on the basis of: Their recognized or highly suspected transmission by drinking water through ingestion, inhalation, or contact Their recognized pathogenic character for humans The severity of their health effects Each micro-organism in this study is described in a summary fact sheet composed of the following items: microbiology, human health effects, geographical distribution, epidemiology, ecology, inactivation/removal, surrogates, environmental detection and research needs. Since much remains unknown about many aspects that are common to viruses, the study features a general section on virus research needs. A special section summarizes the risk management research conducted on waterborne pathogens. Finally, the conclusion gives an overview of the main gaps in current knowledge on waterborne pathogens. Visit the IWA WaterWiki to read and share material related to this title: http://www.iwawaterwiki.org/xwiki/bin/view/Articles/WaterbornePathogens
Download or read book Applied and Environmental Microbiology written by and published by . This book was released on 2000 with total page 998 pages. Available in PDF, EPUB and Kindle. Book excerpt:
