Waterborne infectious diseases are a major public health concern worldwide. Few methods have been established that are capable of measuring human exposure to multiple waterborne pathogens simultaneously using non-invasive samples such as saliva. Most current methods measure expos...
Corsi, Steven R.; Borchardt, Mark A.; Carvin, Rebecca B.; Burch, Tucker R; Spencer, Susan K.; Lutz, Michelle A.; McDermott, Colleen M.; Busse, Kimberly M.; Kleinheinz, Gregory; Feng, Xiaoping; Zhu, Jun
2016-01-01
Waterborne pathogens were measured at three beaches in Lake Michigan, environmental factors for predicting pathogen concentrations were identified, and the risk of swimmer infection and illness was estimated. Waterborne pathogens were detected in 96% of samples collected at three Lake Michigan beaches in summer, 2010. Samples were quantified for 22 pathogens in four microbial categories (human viruses, bovine viruses, protozoa, and pathogenic bacteria). All beaches had detections of human and bovine viruses and pathogenic bacteria indicating influence of multiple contamination sources at these beaches. Occurrence ranged from 40 to 87% for human viruses, 65–87% for pathogenic bacteria, and 13–35% for bovine viruses. Enterovirus, adenovirus A, Salmonella spp., Campylobacter jejuni, bovine polyomavirus, and bovine rotavirus A were present most frequently. Variables selected in multiple regression models used to explore environmental factors that influence pathogens included wave direction, cloud cover, currents, and water temperature. Quantitative Microbial Risk Assessment was done for C. jejuni, Salmonella spp., and enteroviruses to estimate risk of infection and illness. Median infection risks for one-time swimming events were approximately 3 × 10–5, 7 × 10–9, and 3 × 10–7 for C. jejuni, Salmonella spp., and enteroviruses, respectively. Results highlight the importance of investigating multiple pathogens within multiple categories to avoid underestimating the prevalence and risk of waterborne pathogens.
Zhao, Xinyan; Dong, Tao; Yang, Zhaochu; Pires, Nuno; Høivik, Nils
2012-02-07
Waterborne pathogens usually pose a global threat to animals and human beings. There has been a growing demand for convenient and sensitive tools to detect the potential emerging pathogens in water. In this study, a lab-on-a-chip (LOC) device based on the real-time immuno-NASBA (immuno-nucleic acid sequence-based amplification) assay was designed, fabricated and verified. The disposable immuno-NASBA chip is modelled on a 96-well ELISA microplate, which contains 43 reaction chambers inside the bionic channel networks. All valves are designed outside the chip and are reusable. The sample and reagent solutions were pushed into each chamber in turn, which was controlled by the valve system. Notably, the immuno-NASBA chip is completely compatible with common microplate readers in a biological laboratory, and can distinguish multiple waterborne pathogens in water samples quantitatively and simultaneously. The performance of the LOC device was demonstrated by detecting the presence of a synthetic peptide, ACTH (adrenocorticotropic hormone) and two common waterborne pathogens, Escherichia coli (E. coli) and rotavirus, in artificial samples. The results indicated that the LOC device has the potential to quantify traces of waterborne pathogens at femtomolar levels with high specificity, although the detection process was still subject to some factors, such as ribonuclease (RNase) contamination and non-specific adsorption. As an ultra-sensitive tool to quantify waterborne pathogens, the LOC device can be used to monitor water quality in the drinking water system. Furthermore, a series of compatible high-throughput LOC devices for monitoring waterborne pathogens could be derived from this prototype with the same design idea, which may render the complicated immuno-NASBA assays convenient to common users without special training.
Lu, Ding; McDowell, Julia Z.; Davis, George M.; Spear, Robert C.; Remais, Justin V.
2012-01-01
Environmental models, often applied to questions on the fate and transport of chemical hazards, have recently become important in tracing certain environmental pathogens to their upstream sources of contamination. These tools, such as first order decay models applied to contaminants in surface waters, offer promise for quantifying the fate and transport of pathogens with multiple environmental stages and/or multiple hosts, in addition to those pathogens whose environmental stages are entirely waterborne. Here we consider the fate and transport capabilities of the human schistosome Schistosoma japonicum, which exhibits two waterborne stages and is carried by an amphibious intermediate snail host. We present experimentally-derived dispersal estimates for the intermediate snail host and fate and transport estimates for the passive downstream diffusion of cercariae, the waterborne, human-infective parasite stage. Using a one dimensional advective transport model exhibiting first-order decay, we simulate the added spatial reach and relative increase in cercarial concentrations that dispersing snail hosts contribute to downstream sites. Simulation results suggest that snail dispersal can substantially increase the concentrations of cercariae reaching downstream locations, relative to no snail dispersal, effectively putting otherwise isolated downstream sites at increased risk of exposure to cercariae from upstream sources. The models developed here can be applied to other infectious diseases with multiple life-stages and hosts, and have important implications for targeted ecological control of disease spread. PMID:23162675
Contamination of water resources by pathogenic bacteria
2014-01-01
Water-borne pathogen contamination in water resources and related diseases are a major water quality concern throughout the world. Increasing interest in controlling water-borne pathogens in water resources evidenced by a large number of recent publications clearly attests to the need for studies that synthesize knowledge from multiple fields covering comparative aspects of pathogen contamination, and unify them in a single place in order to present and address the problem as a whole. Providing a broader perceptive of pathogen contamination in freshwater (rivers, lakes, reservoirs, groundwater) and saline water (estuaries and coastal waters) resources, this review paper attempts to develop the first comprehensive single source of existing information on pathogen contamination in multiple types of water resources. In addition, a comprehensive discussion describes the challenges associated with using indicator organisms. Potential impacts of water resources development on pathogen contamination as well as challenges that lie ahead for addressing pathogen contamination are also discussed. PMID:25006540
Augustine, Swinburne A. J.; Simmons, Kaneatra J.; Eason, Tarsha N.; Curioso, Clarissa L.; Griffin, Shannon M.; Wade, Timothy J.; Dufour, Alfred; Fout, G. Shay; Grimm, Ann C.; Oshima, Kevin H.; Sams, Elizabeth A.; See, Mary Jean; Wymer, Larry J.
2017-01-01
Waterborne infectious diseases are a major public health concern worldwide. Few methods have been established that are capable of measuring human exposure to multiple waterborne pathogens simultaneously using non-invasive samples such as saliva. Most current methods measure exposure to only one pathogen at a time, require large volumes of individual samples collected using invasive procedures, and are very labor intensive. In this article, we applied a multiplex bead-based immunoassay capable of measuring IgG antibody responses to six waterborne pathogens simultaneously in human saliva to estimate immunoprevalence in beachgoers at Boquerón Beach, Puerto Rico. Further, we present approaches for determining cutoff points to assess immunoprevalence to the pathogens in the assay. For the six pathogens studied, our results show that IgG antibodies against antigens from noroviruses GI.I and GII.4 were more prevalent (60 and 51.6%, respectively) than Helicobacter pylori (21.4%), hepatitis A virus (20.2%), Campylobacter jejuni (8.7%), and Toxoplasma gondii (8%) in the saliva of the study participants. The salivary antibody multiplex immunoassay can be used to examine immunoprevalence of specific pathogens in human populations. PMID:28507984
A Perspective on the Global Pandemic of Waterborne Disease.
Ford, Timothy E; Hamner, Steve
2015-05-29
Waterborne diseases continue to take a heavy toll on the global community, with developing nations, and particularly young children carrying most of the burden of morbidity and mortality. Starting with the historical context, this article explores some of the reasons why this burden continues today, despite our advances in public health over the past century or so. While molecular biology has revolutionized our abilities to define the ecosystems and etiologies of waterborne pathogens, control remains elusive. Lack of basic hygiene and sanitation, and failing infrastructure, remain two of the greatest challenges in the global fight against waterborne disease. Emerging risks continue to be the specter of multiple drug resistance and the ease with which determinants of virulence appear to be transmitted between strains of pathogens, both within and outside the human host.
Jadhav, Ankush; Shanmugham, Buvaneswari; Rajendiran, Anjana; Pan, Archana
2014-10-01
Food and waterborne diseases are a growing concern in terms of human morbidity and mortality worldwide, even in the 21st century, emphasizing the need for new therapeutic interventions for these diseases. The current study aims at prioritizing broad-spectrum antibacterial targets, present in multiple food and waterborne bacterial pathogens, through a comparative genomics strategy coupled with a protein interaction network analysis. The pathways unique and common to all the pathogens under study (viz., methane metabolism, d-alanine metabolism, peptidoglycan biosynthesis, bacterial secretion system, two-component system, C5-branched dibasic acid metabolism), identified by comparative metabolic pathway analysis, were considered for the analysis. The proteins/enzymes involved in these pathways were prioritized following host non-homology analysis, essentiality analysis, gut flora non-homology analysis and protein interaction network analysis. The analyses revealed a set of promising broad-spectrum antibacterial targets, present in multiple food and waterborne pathogens, which are essential for bacterial survival, non-homologous to host and gut flora, and functionally important in the metabolic network. The identified broad-spectrum candidates, namely, integral membrane protein/virulence factor (MviN), preprotein translocase subunits SecB and SecG, carbon storage regulator (CsrA), and nitrogen regulatory protein P-II 1 (GlnB), contributed by the peptidoglycan pathway, bacterial secretion systems and two-component systems, were also found to be present in a wide range of other disease-causing bacteria. Cytoplasmic proteins SecG, CsrA and GlnB were considered as drug targets, while membrane proteins MviN and SecB were classified as vaccine targets. The identified broad-spectrum targets can aid in the design and development of antibacterial agents not only against food and waterborne pathogens but also against other pathogens. Copyright © 2014 Elsevier B.V. All rights reserved.
Glass wool filters for concentrating waterborne viruses and agricultural zoonotic pathogens
USDA-ARS?s Scientific Manuscript database
The key first step in evaluating pathogen levels in suspected contaminated water is concentration. Concentration methods tend to be specific for a particular pathogen group or genus, for example viruses or Cryptosporidium, requiring multiple methods if the sampling program is targeting more than on...
LITERATURE REVIEW OF MOLECULAR METHODS FOR SIMULTANEOUS DETECTION OF PATHOGENS IN WATER
This literature search is a review of molecular technologies (qPCR, microarray, microfluidics and lab-on-a-chip) for simultaneous detection of multiple waterborne pathogens in order to understand the state of the technology. The search content focuses on: pathogen detection witho...
ENGINEERING ASPECTS OF WATERBORNE DISEASE INVESTIGATIONS
As part of a disease outbreak investigation involving drinking water, an engineering investigation may be necessary to determine how or why the pathogen of concern was able to get to the consumer. In many of the US outbreaks, the survival of the pathogen was dependent on multiple...
Hydrologic, land cover and seasonal patterns of waterborne pathogens in great lakes tributaries
USDA-ARS?s Scientific Manuscript database
Great Lakes tributaries deliver waterborne pathogens from a host of sources. To examine the hydrologic, land cover, and seasonal variability of waterborne pathogens, protozoa (2), pathogenic bacteria (4) and human (8) and bovine (8) viruses from eight rivers were monitored in the Great Lakes watersh...
NASA Astrophysics Data System (ADS)
Haramoto, E.
2018-03-01
In this study, the prevalence of various waterborne pathogens in water samples collected in the Kathmandu Valley, Nepal, and the applicability of Escherichia coli as an indicator of pathogen contamination in groundwater were assessed. Fifty-three water samples, including shallow groundwater and river water, were analyzed to examine the presence of protozoan (oo)cysts via fluorescence microscopy and that of viral and bacterial genomes via quantitative PCR. At least one of the seven types of pathogens tested (i.e., Cryptosporidium, Giardia, human adenoviruses, noroviruses of genogroups I and II, group A rotaviruses, and Vibrio cholerae) was detected in 68% (15/22) of the shallow dug well water samples; groundwater in the shallow dug wells was more contaminated compared with that in shallow tube wells (8/15, 53%). River water and sewage samples were contaminated with extremely high concentrations of multiple pathogens, whereas a tap water sample supplied by a water tanker tested positive for human adenoviruses and V. cholerae. The detection of host-specific Bacteroidales genetic markers revealed the effects of human and animal feces on groundwater contamination. The tested pathogens were sometimes detected even in E. coli-negative groundwater samples, indicative of the limitations of using E. coli as an indicator for waterborne pathogens in groundwater.
Identifiability and estimation of multiple transmission pathways in cholera and waterborne disease.
Eisenberg, Marisa C; Robertson, Suzanne L; Tien, Joseph H
2013-05-07
Cholera and many waterborne diseases exhibit multiple characteristic timescales or pathways of infection, which can be modeled as direct and indirect transmission. A major public health issue for waterborne diseases involves understanding the modes of transmission in order to improve control and prevention strategies. An important epidemiological question is: given data for an outbreak, can we determine the role and relative importance of direct vs. environmental/waterborne routes of transmission? We examine whether parameters for a differential equation model of waterborne disease transmission dynamics can be identified, both in the ideal setting of noise-free data (structural identifiability) and in the more realistic setting in the presence of noise (practical identifiability). We used a differential algebra approach together with several numerical approaches, with a particular emphasis on identifiability of the transmission rates. To examine these issues in a practical public health context, we apply the model to a recent cholera outbreak in Angola (2006). Our results show that the model parameters-including both water and person-to-person transmission routes-are globally structurally identifiable, although they become unidentifiable when the environmental transmission timescale is fast. Even for water dynamics within the identifiable range, when noisy data are considered, only a combination of the water transmission parameters can practically be estimated. This makes the waterborne transmission parameters difficult to estimate, leading to inaccurate estimates of important epidemiological parameters such as the basic reproduction number (R0). However, measurements of pathogen persistence time in environmental water sources or measurements of pathogen concentration in the water can improve model identifiability and allow for more accurate estimation of waterborne transmission pathway parameters as well as R0. Parameter estimates for the Angola outbreak suggest that both transmission pathways are needed to explain the observed cholera dynamics. These results highlight the importance of incorporating environmental data when examining waterborne disease. Copyright © 2013 Elsevier Ltd. All rights reserved.
Waterborne Pathogens: Detection Methods and Challenges
Ramírez-Castillo, Flor Yazmín; Loera-Muro, Abraham; Jacques, Mario; Garneau, Philippe; Avelar-González, Francisco Javier; Harel, Josée; Guerrero-Barrera, Alma Lilián
2015-01-01
Waterborne pathogens and related diseases are a major public health concern worldwide, not only by the morbidity and mortality that they cause, but by the high cost that represents their prevention and treatment. These diseases are directly related to environmental deterioration and pollution. Despite the continued efforts to maintain water safety, waterborne outbreaks are still reported globally. Proper assessment of pathogens on water and water quality monitoring are key factors for decision-making regarding water distribution systems’ infrastructure, the choice of best water treatment and prevention waterborne outbreaks. Powerful, sensitive and reproducible diagnostic tools are developed to monitor pathogen contamination in water and be able to detect not only cultivable pathogens but also to detect the occurrence of viable but non-culturable microorganisms as well as the presence of pathogens on biofilms. Quantitative microbial risk assessment (QMRA) is a helpful tool to evaluate the scenarios for pathogen contamination that involve surveillance, detection methods, analysis and decision-making. This review aims to present a research outlook on waterborne outbreaks that have occurred in recent years. This review also focuses in the main molecular techniques for detection of waterborne pathogens and the use of QMRA approach to protect public health. PMID:26011827
Centrifugal sedimentation immunoassays for multiplexed detection of enteric bacteria in ground water
Litvinov, Julia; Moen, Scott T.; Koh, Chung-Yan; ...
2016-01-01
Water-born pathogens pose significant threat to the global population and early detection plays an important role both in making drinking water safe, as well as in diagnostics and treatment of water-borne diseases. We present an innovative centrifugal microfluidic platform (SpinDx) for detection of bacterial pathogens using bead-based immunoassays. Our approach is based on binding of pathogens to antibody-functionalized capture particles followed by sedimentation of the particles through a density-media in a microfluidic disk and quantification by fluorescence microscopy. Our platform is fast (20 min), sensitive (10 3 CFU/mL), requires minimal sample preparation, and can detect multiple pathogens simultaneously with sensitivitymore » similar to that required by the EPA. We demonstrate detection of a panel of enteric bacteria (Escherichia coli, Salmonella typhimurium, Shigella, Listeria, and Campylobacter) at concentrations as low as 10 3 CFU/mL or 30 bacteria per reaction.« less
Centrifugal sedimentation immunoassays for multiplexed detection of enteric bacteria in ground water
Litvinov, Julia; Moen, Scott T.; Koh, Chung-Yan; Singh, Anup K.
2016-01-01
Waterborne pathogens pose significant threat to the global population and early detection plays an important role both in making drinking water safe, as well as in diagnostics and treatment of water-borne diseases. We present an innovative centrifugal sedimentation immunoassay platform for detection of bacterial pathogens in water. Our approach is based on binding of pathogens to antibody-functionalized capture particles followed by sedimentation of the particles through a density-media in a microfluidic disk. Beads at the distal end of the disk are imaged to quantify the fluorescence and determine the bacterial concentration. Our platform is fast (20 min), can detect as few as ∼10 bacteria with minimal sample preparation, and can detect multiple pathogens simultaneously. The platform was used to detect a panel of enteric bacteria (Escherichia coli, Salmonella typhimurium, Shigella, Listeria, and Campylobacter) spiked in tap and ground water samples. PMID:26858815
Detection of Multiple Waterborne Pathogens Using Microsequencing Arrays
Aims: A microarray was developed to simultaneously detect Cryptosporidium parvum, Cryptosporidium hominis, Enterococcus faecium, Bacillus anthracis and Francisella tularensis in water. Methods and Results: A DNA microarray was designed to contain probes that specifically dete...
Development of saliva-based exposure assays for detecting exposure to waterborne pathogens
Identifying which pathogens we are exposed to can be challenging because many types of pathogens can be found in water and many pathogens have similar symptoms. EPA scientists have developed a simple way to measure human exposure to waterborne pathogens.
Global stability of a multiple infected compartments model for waterborne diseases
NASA Astrophysics Data System (ADS)
Wang, Yi; Cao, Jinde
2014-10-01
In this paper, mathematical analysis is carried out for a multiple infected compartments model for waterborne diseases, such as cholera, giardia, and rotavirus. The model accounts for both person-to-person and water-to-person transmission routes. Global stability of the equilibria is studied. In terms of the basic reproduction number R0, we prove that, if R0⩽1, then the disease-free equilibrium is globally asymptotically stable and the infection always disappears; whereas if R0>1, there exists a unique endemic equilibrium which is globally asymptotically stable for the corresponding fast-slow system. Numerical simulations verify our theoretical results and present that the decay rate of waterborne pathogens has a significant impact on the epidemic growth rate. Also, we observe numerically that the unique endemic equilibrium is globally asymptotically stable for the whole system. This statement indicates that the present method need to be improved by other techniques.
Microbiological safety of drinking water: United States and global perspectives.
Ford, T E
1999-01-01
Waterborne disease statistics only begin to estimate the global burden of infectious diseases from contaminated drinking water. Diarrheal disease is dramatically underreported and etiologies seldom diagnosed. This review examines available data on waterborne disease incidence both in the United States and globally together with its limitations. The waterborne route of transmission is examined for bacterial, protozoal, and viral pathogens that either are frequently associated with drinking water (e.g., Shigella spp.), or for which there is strong evidence implicating the waterborne route of transmission (e.g., Leptospira spp.). In addition, crucial areas of research are discussed, including risks from selection of treatment-resistant pathogens, importance of environmental reservoirs, and new methodologies for pathogen-specific monitoring. To accurately assess risks from waterborne disease, it is necessary to understand pathogen distribution and survival strategies within water distribution systems and to apply methodologies that can detect not only the presence, but also the viability and infectivity of the pathogen. Images Figure 1 Figure 2 PMID:10229718
BACTERIAL WATERBORNE PATHOGENS
Bacterial pathogens are examples of classical etiological agents of waterborne disease. While these agents no longer serve as major threats to U.S. water supplies, they are still important pathogens in areas with substandard sanitation and poor water treatment facilities. In th...
Glass wool filters for concentrating waterborne viruses and agricultural zoonotic pathogens
Millen, Hana T.; Gonnering, Jordan C.; Berg, Ryan K.; Spencer, Susan K.; Jokela, William E.; Pearce, John M.; Borchardt, Jackson S.; Borchardt, Mark A.
2012-01-01
The key first step in evaluating pathogen levels in suspected contaminated water is concentration. Concentration methods tend to be specific for a particular pathogen group, for example US Environmental Protection Agency Method 1623 for Giardia and Cryptosporidium1, which means multiple methods are required if the sampling program is targeting more than one pathogen group. Another drawback of current methods is the equipment can be complicated and expensive, for example the VIRADEL method with the 1MDS cartridge filter for concentrating viruses2. In this article we describe how to construct glass wool filters for concentrating waterborne pathogens. After filter elution, the concentrate is amenable to a second concentration step, such as centrifugation, followed by pathogen detection and enumeration by cultural or molecular methods. The filters have several advantages. Construction is easy and the filters can be built to any size for meeting specific sampling requirements. The filter parts are inexpensive, making it possible to collect a large number of samples without severely impacting a project budget. Large sample volumes (100s to 1,000s L) can be concentrated depending on the rate of clogging from sample turbidity. The filters are highly portable and with minimal equipment, such as a pump and flow meter, they can be implemented in the field for sampling finished drinking water, surface water, groundwater, and agricultural runoff. Lastly, glass wool filtration is effective for concentrating a variety of pathogen types so only one method is necessary. Here we report on filter effectiveness in concentrating waterborne human enterovirus, Salmonella enterica, Cryptosporidium parvum, and avian influenza virus.
Glass Wool Filters for Concentrating Waterborne Viruses and Agricultural Zoonotic Pathogens
Millen, Hana T.; Gonnering, Jordan C.; Berg, Ryan K.; Spencer, Susan K.; Jokela, William E.; Pearce, John M.; Borchardt, Jackson S.; Borchardt, Mark A.
2012-01-01
The key first step in evaluating pathogen levels in suspected contaminated water is concentration. Concentration methods tend to be specific for a particular pathogen group, for example US Environmental Protection Agency Method 1623 for Giardia and Cryptosporidium1, which means multiple methods are required if the sampling program is targeting more than one pathogen group. Another drawback of current methods is the equipment can be complicated and expensive, for example the VIRADEL method with the 1MDS cartridge filter for concentrating viruses2. In this article we describe how to construct glass wool filters for concentrating waterborne pathogens. After filter elution, the concentrate is amenable to a second concentration step, such as centrifugation, followed by pathogen detection and enumeration by cultural or molecular methods. The filters have several advantages. Construction is easy and the filters can be built to any size for meeting specific sampling requirements. The filter parts are inexpensive, making it possible to collect a large number of samples without severely impacting a project budget. Large sample volumes (100s to 1,000s L) can be concentrated depending on the rate of clogging from sample turbidity. The filters are highly portable and with minimal equipment, such as a pump and flow meter, they can be implemented in the field for sampling finished drinking water, surface water, groundwater, and agricultural runoff. Lastly, glass wool filtration is effective for concentrating a variety of pathogen types so only one method is necessary. Here we report on filter effectiveness in concentrating waterborne human enterovirus, Salmonella enterica, Cryptosporidium parvum, and avian influenza virus. PMID:22415031
Stokdyk, Joel P; Firnstahl, Aaron D; Spencer, Susan K; Burch, Tucker R; Borchardt, Mark A
2016-06-01
The limit of detection (LOD) for qPCR-based analyses is not consistently defined or determined in studies on waterborne pathogens. Moreover, the LODs reported often reflect the qPCR assay alone rather than the entire sample process. Our objective was to develop an approach to determine the 95% LOD (lowest concentration at which 95% of positive samples are detected) for the entire process of waterborne pathogen detection. We began by spiking the lowest concentration that was consistently positive at the qPCR step (based on its standard curve) into each procedural step working backwards (i.e., extraction, secondary concentration, primary concentration), which established a concentration that was detectable following losses of the pathogen from processing. Using the fraction of positive replicates (n = 10) at this concentration, we selected and analyzed a second, and then third, concentration. If the fraction of positive replicates equaled 1 or 0 for two concentrations, we selected another. We calculated the LOD using probit analysis. To demonstrate our approach we determined the 95% LOD for Salmonella enterica serovar Typhimurium, adenovirus 41, and vaccine-derived poliovirus Sabin 3, which were 11, 12, and 6 genomic copies (gc) per reaction (rxn), respectively (equivalent to 1.3, 1.5, and 4.0 gc L(-1) assuming the 1500 L tap-water sample volume prescribed in EPA Method 1615). This approach limited the number of analyses required and was amenable to testing multiple genetic targets simultaneously (i.e., spiking a single sample with multiple microorganisms). An LOD determined this way can facilitate study design, guide the number of required technical replicates, aid method evaluation, and inform data interpretation. Published by Elsevier Ltd.
Stokdyk, Joel P.; Firnstahl, Aaron; Spencer, Susan K.; Burch, Tucker R; Borchardt, Mark A.
2016-01-01
The limit of detection (LOD) for qPCR-based analyses is not consistently defined or determined in studies on waterborne pathogens. Moreover, the LODs reported often reflect the qPCR assay alone rather than the entire sample process. Our objective was to develop an approach to determine the 95% LOD (lowest concentration at which 95% of positive samples are detected) for the entire process of waterborne pathogen detection. We began by spiking the lowest concentration that was consistently positive at the qPCR step (based on its standard curve) into each procedural step working backwards (i.e., extraction, secondary concentration, primary concentration), which established a concentration that was detectable following losses of the pathogen from processing. Using the fraction of positive replicates (n = 10) at this concentration, we selected and analyzed a second, and then third, concentration. If the fraction of positive replicates equaled 1 or 0 for two concentrations, we selected another. We calculated the LOD using probit analysis. To demonstrate our approach we determined the 95% LOD for Salmonella enterica serovar Typhimurium, adenovirus 41, and vaccine-derived poliovirus Sabin 3, which were 11, 12, and 6 genomic copies (gc) per reaction (rxn), respectively (equivalent to 1.3, 1.5, and 4.0 gc L−1 assuming the 1500 L tap-water sample volume prescribed in EPA Method 1615). This approach limited the number of analyses required and was amenable to testing multiple genetic targets simultaneously (i.e., spiking a single sample with multiple microorganisms). An LOD determined this way can facilitate study design, guide the number of required technical replicates, aid method evaluation, and inform data interpretation.
DEVELOPMENT OF HUMAN BIOMARKERS OF EXPOSURE TO WATERBORNE PATHOGENS
Contaminated drinking water is major source of waterborne diseases. EPA has published a drinking water contaminant candidate list (CCL) that contains a number of pathogens that potentially could be regulated in drinking water. Studies indicate that certain viral pathogens (adenov...
NASA Astrophysics Data System (ADS)
Bridge, J. W.; Oliver, D.; Heathwaite, A.; Banwart, S.; Going Underground: Human Pathogens in The Soil-Water Environment Working Group
2010-12-01
We present the findings and recommendations of a recent UK working group convened to identify research priorities in environmental science and epidemiology of waterborne pathogens. Robust waterborne disease surveillance in the developed world remains a critical need, despite broad success of regulation and water treatment. Recent estimates suggest waterborne pathogens result in between 12 million and 19.5 million cases of illness per year in the US alone. Across the developed world, the value of preventing acute waterborne disease in 150 million people using small community or single-user supplies is estimated at above US$ 4,671 million. The lack of a high quality, reliable environmental knowledge base for waterborne pathogens is a key obstacle. Substantial improvements in understanding of pathogen survival and transport in soils, sediments and water are required both to aid identification of environmental aetiologies for organisms isolated in disease cases and to support novel mitigation responses directed towards specific exposure risks. However, the focus in monitoring and regulation on non-pathogenic faecal indicator organisms (easier and cheaper to detect in water samples) creates a lack of motivation to conduct detailed environmental studies of the actual pathogens likely to be encountered in disease surveillance. Robust disease surveillance may be regarded as an essential objective in epidemiology; but it constitutes a significant shift in perspective for the water industry. The health sector can play a vital role in changing attitudes by explicitly placing value on environmental water research which looks beyond compliance with water quality standards towards informing disease surveillance and influencing health outcomes. The summary of critical research priorities we outline provides a focus for developing and strengthening dialogue between health and water sectors to achieve a common goal - sophisticated management of waterborne diseases through sophisticated understanding of their environmental sources and dynamics.
DETECTING CCL-RELATED, EMERGING AND REGULATED WATERBORNE HUMAN PROTOZOA FOR EXPOSURE ASSESSMENT
Pathogenic intestinal protozoa (Giardia, Cryptosporidium) are significant etiological agents in the transmission of waterborne disease. Other emerging protozoa are also likely causes of waterborne disease. Toxoplasma gondii has been implicated in causing waterborne disease in N...
Waterborne Pathogens: The Protozoans.
Moss, Joseph Anthony
2016-09-01
Waterborne diseases associated with polluted recreational and potable waters have been documented for more than a century. Key microbial protozoan parasites, such as Cryptosporidium and Giardia, are causative agents for gastrointestinal disease worldwide. Although not a first-line diagnostic approach for these diseases, medical imaging, such as radiography, computed tomography, magnetic resonance imaging, ultrasonography, and nuclear medicine technologies, can be used to evaluate patients with long-term effects. This article describes protozoan pathogens that affect human health, treatment of common waterborne pathogen-related diseases, and associated medical imaging. ©2016 American Society of Radiologic Technologists.
ADEQUACY OF DISINFECTION FOR CONTROL OF NEWLY RECOGNIZED WATERBORNE PATHOGENS
Agents recently recognized as causes or potential causes of waterborne outbreaks include pathogenic bacteria (Campylobacter jejuni, Yersinia enterocoliticia), viruses (rotavirus, Norwalk virus and other poorly defined viral agents) and Giardia lamblia, a protozoan agent. Although...
Rapid Waterborne Pathogen Detection with Mobile Electronics.
Wu, Tsung-Feng; Chen, Yu-Chen; Wang, Wei-Chung; Kucknoor, Ashwini S; Lin, Che-Jen; Lo, Yu-Hwa; Yao, Chun-Wei; Lian, Ian
2017-06-09
Pathogen detection in water samples, without complex and time consuming procedures such as fluorescent-labeling or culture-based incubation, is essential to public safety. We propose an immunoagglutination-based protocol together with the microfluidic device to quantify pathogen levels directly from water samples. Utilizing ubiquitous complementary metal-oxide-semiconductor (CMOS) imagers from mobile electronics, a low-cost and one-step reaction detection protocol is developed to enable field detection for waterborne pathogens. 10 mL of pathogen-containing water samples was processed using the developed protocol including filtration enrichment, immune-reaction detection and imaging processing. The limit of detection of 10 E. coli O157:H7 cells/10 mL has been demonstrated within 10 min of turnaround time. The protocol can readily be integrated into a mobile electronics such as smartphones for rapid and reproducible field detection of waterborne pathogens.
Jardine, Jocelyn Leonie; Abia, Akebe Luther King; Mavumengwana, Vuyo; Ubomba-Jaswa, Eunice
2017-09-15
Hot spring water may harbour emerging waterborne opportunistic pathogens that can cause infections in humans. We have investigated the diversity and antimicrobial resistance of culturable emerging and opportunistic bacterial pathogens, in water and sediment of hot springs located in Limpopo, South Africa. Aerobic bacteria were cultured and identified using 16S ribosomal DNA (rDNA) gene sequencing. The presence of Legionella spp. was investigated using real-time polymerase chain reaction. Isolates were tested for resistance to ten antibiotics representing six different classes: β-lactam (carbenicillin), aminoglycosides (gentamycin, kanamycin, streptomycin), tetracycline, amphenicols (chloramphenicol, ceftriaxone), sulphonamides (co-trimoxazole) and quinolones (nalidixic acid, norfloxacin). Gram-positive Kocuria sp. and Arthrobacter sp. and gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were isolated, all recognised as emerging food-borne pathogens. Legionella spp. was not detected throughout the study. Isolates of Kocuria , Arthrobacter and Hafnia and an unknown species of the class Gammaproteobacteria were resistant to two antibiotics in different combinations of carbenicillin, ceftriaxone, nalidixic acid and chloramphenicol. Cronobacter sp. was sensitive to all ten antibiotics. This study suggests that hot springs are potential reservoirs for emerging opportunistic pathogens, including multiple antibiotic resistant strains, and highlights the presence of unknown populations of emerging and potential waterborne opportunistic pathogens in the environment.
Hydrologic, land cover, and seasonal patterns of waterborne pathogens in Great Lakes tributaries
Lenaker, Peter L.; Corsi, Steven; Borchardt, Mark A.; Spencer, Susan K.; Baldwin, Austin K.; Lutz, Michelle A.
2017-01-01
Great Lakes tributaries are known to deliver waterborne pathogens from a host of sources. To examine the hydrologic, land cover, and seasonal patterns of waterborne pathogens (i.e. protozoa (2), pathogenic bacteria (4) human viruses, (8) and bovine viruses (8)) eight rivers were monitored in the Great Lakes Basin over 29 months from February 2011 to June 2013. Sampling locations represented a wide variety of land cover classes from urban to agriculture to forest. A custom automated pathogen sampler was deployed at eight sampling locations which provided unattended, flow-weighted, large-volume (120–1630 L) sampling. Human and bovine viruses and pathogenic bacteria were detected by real-time qPCR in 16%, 14%, and 1.4% of 290 samples collected while protozoa were never detected. The most frequently detected pathogens were: bovine polyomavirus (11%), and human adenovirus C, D, F (9%). Human and bovine viruses were present in 16.9% and 14.8% of runoff-event samples (n = 189) resulting from precipitation and snowmelt, and 13.9% and 12.9% of low-flow samples (n = 101), respectively, indicating multiple delivery mechanisms could be influential. Data indicated human and bovine virus prevalence was different depending on land cover within the watershed. Occurrence, concentration, and flux of human viruses were greatest in samples from the three sampling locations with greater than 25% urban influence than those with less than 25% urban influence. Similarly, occurrence, concentration, and flux of bovine viruses were greatest in samples from the two sampling locations with greater than 50 cattle/km2 than those with less than 50 cattle/km2. In seasonal analysis, human and bovine viruses occurred more frequently in spring and winter seasons than during the fall and summer. Concentration, occurrence, and flux in the context of hydrologic condition, seasonality, and land use must be considered for each watershed individually to develop effective watershed management strategies for pathogen reduction.
Gibney, Katherine B; O'Toole, Joanne; Sinclair, Martha; Leder, Karin
2017-06-01
AbstractUniversal access to safe drinking water is a global priority. To estimate the annual disease burden of campylobacteriosis, nontyphoidal salmonellosis, cryptosporidiosis, giardiasis, and norovirus attributable to waterborne transmission in Australia, we multiplied regional World Health Organization (WHO) estimates of the proportion of cases attributable to waterborne transmission by estimates of all-source disease burden for each study pathogen. Norovirus was attributed as causing the most waterborne disease cases (479,632; 95% uncertainty interval [UI]: 0-1,111,874) followed by giardiasis and campylobacteriosis. The estimated waterborne disability-adjusted life year (DALY) burden for campylobacteriosis (2,004; 95% UI: 0-5,831) was 7-fold greater than other study pathogens and exceeded the WHO guidelines for drinking water quality (1 × 10 -6 DALY per person per year) by 90-fold. However, these estimates include disease transmitted via either drinking or recreational water exposure. More precise country-specific and drinking water-specific attribution estimates would better define the health burden from drinking water and inform changes to treatment requirements.
U.S. ENVIRONMENTAL PROTECTION AGENCY'S REGULATION AND MANAGEMENT OF WATERBORNE VIRUSES
The U.S. Environmental Protection Agency (USEPA) manages waterborne viruses and other pathogens through the establishment of rules and regulations that are designed to ensure public health protection. The rules that currently regulate pathogens focus on the management of viruses...
GLOBAL WARMING AND TRANS-BOUNDARY MOVEMENT OF WATERBORNE MICROBIAL PATHOGENS
Subtle increases in temperatures can have profound impacts on the prevalence of various waterborne microbial pathogens. Such impacts may be seen in three major areas: 1) fecally-contaminated drinking waters; 2) fresh produce that has been irrigated or processed with contaminated ...
Brouwer, Andrew F; Masters, Nina B; Eisenberg, Joseph N S
2018-04-20
Waterborne enteric pathogens remain a global health threat. Increasingly, quantitative microbial risk assessment (QMRA) and infectious disease transmission modeling (IDTM) are used to assess waterborne pathogen risks and evaluate mitigation. These modeling efforts, however, have largely been conducted independently for different purposes and in different settings. In this review, we examine the settings where each modeling strategy is employed. QMRA research has focused on food contamination and recreational water in high-income countries (HICs) and drinking water and wastewater in low- and middle-income countries (LMICs). IDTM research has focused on large outbreaks (predominately LMICs) and vaccine-preventable diseases (LMICs and HICs). Human ecology determines the niches that pathogens exploit, leading researchers to focus on different risk assessment research strategies in different settings. To enhance risk modeling, QMRA and IDTM approaches should be integrated to include dynamics of pathogens in the environment and pathogen transmission through populations.
Immunomagnetic separation for MEMS-based biosensor of waterborne pathogens detection
NASA Astrophysics Data System (ADS)
Guo, Jianjiang; Zhang, Rongbiao
2017-07-01
Rapid isolation and detection of special pathogens present in environmental drinking water is critical for water quality monitoring. Numerical analysis and experimental investigations on immunomagnetic capture and isolation of waterborne pathogens with magnetic nanoparticles (MNPs) in microfluidic channel are performed. A finite-element COMSOL-based model is established to demonstrate the novel method of on-chip capturing pathogens using MNPs together with periodic pulse magnetic field. Simulation results determine the optimum magnetic pole current and switching frequency for magnetic separation. With the magnetic isolation experiment platform built up, as a pathogen example of Escherichia coli O157:H7, the performance of the method is experimentally verified. Both numerical and experimental results are found to agree reasonably well. Results of these investigations show that the capture efficiency of the immunomagnetic separation method is more than 92%, which could be encouraging for the design and optimization of MEMS-based biosensor of waterborne pathogen detection.
Purpose of reviewThis review discusses the utility of pathogen-specific antibody biomarkers for improving estimates of the population burden of waterborne infections, assessing the fraction of infections that can be prevented by specific water treatments, and understanding transm...
Water treatment and wastewater disposal practices have reduced the death rate from waterborne illness. However, the number of individuals made ill, and the number of outbreaks of waterborne disease still fluctuates greatly. This is partly due to newly recognized disease agents,...
Exum, Natalie G; Pisanic, Nora; Granger, Douglas A; Schwab, Kellogg J; Detrick, Barbara; Kosek, Margaret; Egorov, Andrey I; Griffin, Shannon M; Heaney, Christopher D
2016-09-01
This review discusses the utility of pathogen-specific antibody biomarkers for improving estimates of the population burden of waterborne infections, assessing the fraction of infections that can be prevented by specific water treatments, and understanding transmission routes and the natural history and ecology of disease in different populations (including asymptomatic infection rates). We review recent literature on the application of pathogen-specific antibody response data to estimate incidence and prevalence of acute infections and their utility to assess the contributions of waterborne transmission pathways. Advantages and technical challenges associated with the use of serum versus minimally invasive salivary antibody biomarkers in cross-sectional and prospective surveys are discussed. We highlight recent advances and challenges and outline future directions for research, development, and application of antibody-based and other immunological biomarkers of waterborne infections.
Mortality from selected diseases that can be transmitted by water - United States, 2003-2009.
Gargano, J W; Adam, E A; Collier, S A; Fullerton, K E; Feinman, S J; Beach, M J
2017-06-01
Diseases spread by water are caused by fecal-oral, contact, inhalation, or other routes, resulting in illnesses affecting multiple body systems. We selected 13 pathogens or syndromes implicated in waterborne disease outbreaks or other well-documented waterborne transmission (acute otitis externa, Campylobacter, Cryptosporidium, Escherichia coli (E. coli), free-living ameba, Giardia, Hepatitis A virus, Legionella (Legionnaires' disease), nontuberculous mycobacteria (NTM), Pseudomonas-related pneumonia or septicemia, Salmonella, Shigella, and Vibrio). We documented annual numbers of deaths in the United States associated with these infections using a combination of death certificate data, nationally representative hospital discharge data, and disease-specific surveillance systems (2003-2009). We documented 6,939 annual total deaths associated with the 13 infections; of these, 493 (7%) were caused by seven pathogens transmitted by the fecal-oral route. A total of 6,301 deaths (91%) were associated with infections from Pseudomonas, NTM, and Legionella, environmental pathogens that grow in water system biofilms. Biofilm-associated pathogens can cause illness following inhalation of aerosols or contact with contaminated water. These findings suggest that most mortality from these 13 selected infections in the United States does not result from classical fecal-oral transmission but rather from other transmission routes.
Global Warming and Trans-Boundary Movement of Waterborne Microbial Pathogens - Book Chapter
Subtle increases in temperature can have profound impacts on the prevalence of various waterborne microbial pathogens. Such impacts may be seen in three major areas, 1) fecally contaminated drinking water, 2) fresh produce that has been irrigated or processed with contaminated wa...
MEASURE OCCURRENCE AND EXPOSURE TO CCL-RELATED, EMERGING AND REGULATED WATERBORNE HUMAN PROTOZOA
Pathogenic waterborne protozoa (Giardia, Cryptosporidium) have been identified as significant etiological agents in the transmission of waterborne disease. Microsporidians, which are on the Agency's Contaminant Candidate List, are obligate intracellular parasites of invertebrate...
DEVELOPMENT OF A BIOMARKER SYSTEM FOR DETECTING EXPOSURE TO WATERBORNE VIRAL PATHOGENS
EPA has published a drinking water contaminant candidate list (CCL) that includes waterborne pathogens and chemicals that may be considered for regulation at a future date. For each contaminant on the CCL, the Agency will need sufficient data to conduct analyses on the extent of...
THE ROLE OF FILTRATION IN PREVENTING WATERBORNE DISEASE
Filtration is an important treatment process in the removal of pathogenic microorganisms and the prevention of waterborne disease. Historically, filtration was responsible for reducing death and illness from waterborne disease in 1871 in Germany. Other early examples in the U.S. ...
Exum, Natalie G.; Pisanic, Nora; Granger, Douglas A.; Schwab, Kellogg J.; Detrick, Barbara; Kosek, Margaret; Egorov, Andrey I.; Griffin, Shannon M.; Heaney, Christopher D.
2016-01-01
Purpose of review This review discusses the utility of pathogen-specific antibody biomarkers for improving estimates of the population burden of waterborne infections, assessing the fraction of infections that can be prevented by specific water treatments, and understanding transmission routes and the natural history and ecology of disease in different populations (including asymptomatic infection rates). Recent findings We review recent literature on the application of pathogen-specific antibody response data to estimate incidence and prevalence of acute infections and their utility to assess the contributions of waterborne transmission pathways. Advantages and technical challenges associated with the use of serum versus minimally invasive salivary antibody biomarkers in cross-sectional and prospective surveys are discussed. Summary We highlight recent advances and challenges and outline future directions for research, development, and application of antibody-based and other immunological biomarkers of waterborne infections. PMID:27352014
Jardine, Jocelyn Leonie; Mavumengwana, Vuyo
2017-01-01
Hot spring water may harbour emerging waterborne opportunistic pathogens that can cause infections in humans. We have investigated the diversity and antimicrobial resistance of culturable emerging and opportunistic bacterial pathogens, in water and sediment of hot springs located in Limpopo, South Africa. Aerobic bacteria were cultured and identified using 16S ribosomal DNA (rDNA) gene sequencing. The presence of Legionella spp. was investigated using real-time polymerase chain reaction. Isolates were tested for resistance to ten antibiotics representing six different classes: β-lactam (carbenicillin), aminoglycosides (gentamycin, kanamycin, streptomycin), tetracycline, amphenicols (chloramphenicol, ceftriaxone), sulphonamides (co-trimoxazole) and quinolones (nalidixic acid, norfloxacin). Gram-positive Kocuria sp. and Arthrobacter sp. and gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were isolated, all recognised as emerging food-borne pathogens. Legionella spp. was not detected throughout the study. Isolates of Kocuria, Arthrobacter and Hafnia and an unknown species of the class Gammaproteobacteria were resistant to two antibiotics in different combinations of carbenicillin, ceftriaxone, nalidixic acid and chloramphenicol. Cronobacter sp. was sensitive to all ten antibiotics. This study suggests that hot springs are potential reservoirs for emerging opportunistic pathogens, including multiple antibiotic resistant strains, and highlights the presence of unknown populations of emerging and potential waterborne opportunistic pathogens in the environment. PMID:28914802
García-Gil, Alejandro; Gasco-Cavero, Samanta; Garrido, Eduardo; Mejías, Miguel; Epting, Jannis; Navarro-Elipe, Mercedes; Alejandre, Carmen; Sevilla-Alcaine, Elena
2018-08-15
The implications of intensive use of shallow geothermal energy resources in shallow urban aquifers are still not known for waterborne pathogens relevant to human health. Firstly, we hypothesized that waterborne enteric pathogens would be relatively increased in heated groundwater plumes. To prove this, microbiological sampling of 31 piezometers covering the domain of an urban groundwater body affected by microbiological contamination and energetically exploited by 70 groundwater heat pump systems was performed. Mean differences of pathogenic bacteria contents between impacted and non-impacted monitoring points were assessed with a two-tailed independent Student's t-test or Mann-Whitney U and correlation coefficients were also calculated. Surprisingly, the results obtained revealed a significant and generalized decrease in waterborne pathogen contents in thermally impacted piezometers compared to that of non-impacted piezometers. This decrease is hypothesized to be caused by a heat shock to bacteria within the heat exchangers. The statistically significant negative correlations obtained between waterborne pathogen counts and temperature could be explained by the spatial distribution of the bacteria, finding that bacteria start to recover with increasing distance from the injection point. Also, different behavior groups fitting exponential regression models were found for the bacteria species studied, justified by the different presence and influence of several aquifer parameters and major, minor and trace elements studied, as well as the coexistence with other bacteria species. The results obtained from this work reinforce the concept of shallow geothermal resources as a clean energy source, as they could also provide the basis to control the pathogenic bacteria contents in groundwater bodies. Copyright © 2018 Elsevier B.V. All rights reserved.
One criterion on which chlorine treatment of water may be based is the concentration (C) in mg/l multiplied by the time (t) in min of exposure or Ct values. We compared different Ct values on waterborne pathogenic bacteria by cultural assay for viability and 2 assays that mea...
The role of water in healthcare-associated infections.
Decker, Brooke K; Palmore, Tara N
2013-08-01
The aim is to discuss the epidemiology of infections that arise from contaminated water in healthcare settings, including Legionnaires' disease, other Gram-negative pathogens, nontuberculous mycobacteria, and fungi. Legionella can colonize a hospital water system and infect patients despite use of preventive disinfectants. Evidence-based measures are available for secondary prevention. Vulnerable patients can develop healthcare-associated infections with waterborne organisms that are transmitted by colonization of plumbing systems, including sinks and their fixtures. Room humidifiers and decorative fountains have been implicated in serious outbreaks, and pose unwarranted risks in healthcare settings. Design of hospital plumbing must be purposeful and thoughtful to avoid the features that foster growth and dissemination of Legionella and other pathogens. Exposure of patients who have central venous catheters and other invasive devices to tap water poses a risk for infection with waterborne pathogens. Healthcare facilities must conduct aggressive clinical surveillance for Legionnaires' disease and other waterborne infections in order to detect and remediate an outbreak promptly. Hand hygiene is the most important measure to prevent transmission of other Gram-negative waterborne pathogens in the healthcare setting.
The Role of Water in Healthcare-Associated Infections
Decker, Brooke K.; Palmore, Tara N.
2017-01-01
Purpose of review The aim is to discuss the epidemiology of infections that arise from contaminated water in healthcare settings, including Legionnaire’s disease, other Gram-negative pathogens, nontuberculous mycobacteria, and fungi. Recent findings Legionella can colonize a hospital water system and infect patients despite use of preventive disinfectants. Evidence-based measures are available for secondary prevention. Vulnerable patients can develop care-associated infections with waterborne organisms that are transmitted by colonization of plumbing systems, including sinks and their fixtures. Room humidifiers and decorative fountains have been implicated in serious outbreaks, and pose unwarranted risks in healthcare settings. Summary Design of hospital plumbing must be purposeful and thoughtful to avoid the features that foster growth and dissemination of Legionella and other pathogens. Exposure of patients who have central venous catheters and other invasive devices to tap water poses a risk for infection with waterborne pathogens. Healthcare facilities must conduct aggressive clinical surveillance for Legionnaire’s disease and other waterborne infections in order to detect and remediate an outbreak promptly. Hand hygiene is the most important measure to prevent transmission of other Gram-negative waterborne pathogens in the healthcare setting. PMID:23806897
USDA-ARS?s Scientific Manuscript database
The limit of detection (LOD) for qPCR-based analyses is not consistently defined or determined in studies on waterborne pathogens. Moreover, the LODs reported often reflect the qPCR assay rather than the entire sample process. Our objective was to develop a method to determine the 95% LOD (lowest co...
Reversible assembly of magnetized particles: Application to water-borne pathogen enumeration
NASA Astrophysics Data System (ADS)
Ramadan, Qasem
2009-12-01
Reversible assembly of magnetized particles and cells has been proposed and implemented. The approach is based on magnetized particles or magnetically labeled cell immobilization in an array of individual particle/cell for optical counting. The device has been tested for few types of magnetic particles and one water-borne pathogen: Giardia Lamblia. An individual particle immobilization efficiency of 92% was achieved.
[The pathogens responsible for waterborne infections: the biological risk for agricultural laborer].
Dragone, M; Gioffrè, A; Marramao, A
2007-01-01
The presence of microbiological agents in waters intended for human consumption, irrigation and recreational activity, is a significant risk for the human health. Recent epidemiological data demonstrate an increase of the diseases caused by waterborne pathogens, especially of the gastroenteritis infections, in the industrialized countries. Numerous studies have evidenced the contamination of deep and surface waters; bacteria within contaminated water represent a highly diversified group, that are usually encountered in wastewater and sewage. In particular the pollution of the groundwater is much dangerous, from the viewpoint of drinking water safety. In fact, the groundwaters whenever polluted, have an insufficient self-purification. The aim of this paper was to estimate the presence of waterborne pathogens in groundwater intended for the irrigation. Well water samples were collected at eighteen different agricultural areas located in Calabria and analyzed for the presence of waterborne pathogens. The results shows a diffuse pollution of the wells in all of the monitorated zones. Then out of eighteen examined samples were positive for total coliforms and Enterococcus spp. and the value of total microbial contamination were higher than 100 UFC/ml; eight of these ten wells were contaminated from Salmonella spp. and Shigella spp. (minimal value 2x10(1) UFC/l; maximum value 2x10(3) UFC/l).
Recommended advanced techniques for waterborne pathogen detection in developing countries.
Alhamlan, Fatimah S; Al-Qahtani, Ahmed A; Al-Ahdal, Mohammed N
2015-02-19
The effect of human activities on water resources has expanded dramatically during the past few decades, leading to the spread of waterborne microbial pathogens. The total global health impact of human infectious diseases associated with pathogenic microorganisms from land-based wastewater pollution was estimated to be approximately three million disability-adjusted life years (DALY), with an estimated economic loss of nearly 12 billion US dollars per year. Although clean water is essential for healthy living, it is not equally granted to all humans. Indeed, people who live in developing countries are challenged every day by an inadequate supply of clean water. Polluted water can lead to health crises that in turn spread waterborne pathogens. Taking measures to assess the water quality can prevent these potential risks. Thus, a pressing need has emerged in developing countries for comprehensive and accurate assessments of water quality. This review presents current and emerging advanced techniques for assessing water quality that can be adopted by authorities in developing countries.
Assessing Exposure to Waterborne Pathogens
In the U.S, and other developed countries, application of the multi-barrier approach for protecting and treating water supplies has led to the virtual elimination of waterborne threats such as cholera and typhoid. Nevertheless, illnesses associated with contaminated drinking wat...
DETECTION OF MICROSPORIDIA IN ENVIRONMENTAL WATERS
The health effects associated with various waterborne pathogenic microorganisms has been well documented. During the last quarter century protozoan parasites like Giardia and Cryptosporidium have been added to this group. To date, however, the causes of many cases of waterborne...
In 1971, the U.S. Environmental Protection Agency (EPA) entered into a long term agreement with the Centers for Disease Control and Prevention (CDC) to gather data on the occurrence of waterborne illness. It is difficult however to know what effects increases in surveillance hav...
Bridle, Helen; Balharry, Dominique; Gaiser, Birgit; Johnston, Helinor
2015-09-15
Contaminated drinking water is one of the most important environmental contributors to the human disease burden. Monitoring of water for the presence of pathogens is an essential part of ensuring drinking water safety. In order to assess water quality it is essential to have methods available to sample and detect the type, level and viability of pathogens in water which are effective, cheap, quick, sensitive, and where possible high throughput. Nanotechnology has the potential to drastically improve the monitoring of waterborne pathogens when compared to conventional approaches. To date, there have been no reviews that outline the applications of nanotechnology in this area despite increasing exploitation of nanotechnology for this purpose. This review is therefore the first overview of the state-of-the-art in the application of nanotechnology to waterborne pathogen sampling and detection schemes. Research in this field has been centered on the use of engineered nanomaterials. The effectiveness and limitations of nanomaterial-based approaches is outlined. A future outlook of the advances that are likely to emerge in this area, as well as recommendations for areas of further research are provided.
Williams, Margaret M; Armbruster, Catherine R; Arduino, Matthew J
2013-01-01
Several bacterial species that are natural inhabitants of potable water distribution system biofilms are opportunistic pathogens important to sensitive patients in healthcare facilities. Waterborne healthcare-associated infections (HAI) may occur during the many uses of potable water in the healthcare environment. Prevention of infection is made more challenging by lack of data on infection rate and gaps in understanding of the ecology, virulence, and infectious dose of these opportunistic pathogens. Some healthcare facilities have been successful in reducing infections by following current water safety guidelines. This review describes several infections, and remediation steps that have been implemented to reduce waterborne HAIs.
WATERBORNE PATHOGENS IN URBAN WATERSHEDS
Pathogens are microorganisms that can cause sickness or even death. A serious concern for managers of water resources, pathogens in the urban environment easily enter waters through a number of pathways, including discharge of inadequately treated sewage, stormwater runoff, combi...
ESTABLISH AND STANDARDIZE METHODOLOGY FOR DETECTION OF WATERBORNE VIRUSES FROM HUMAN SOURCES
Research is conducted to develop and standardize methods to detect and measure occurrence of human enteric viruses that cause waterborne disease. The viruses of concern include the emerging pathogens--hepatitis E virus and group B rotaviruses. Also of concern are the coxsackiev...
MICROBES IN DRINKING WATER: RECENT EPIDEMIOLOGICAL RESEARCH TO ASSESS WATERBORNE RISKS
The waterborne transmission of enteric pathogens to humans causes illnesses that occur as an epidemic (a temporal excess of cases over some background level of disease), often called an outbreak, or as endemic disease (a background of ongoing disease prevalence that can be consta...
Microbiology: Detection of Bacterial Pathogens and Their Occurrence.
ERIC Educational Resources Information Center
Reasoner, Donald J.
1978-01-01
Presents a literature review of bacterial pathogens that are related to water pollution, covering publications from 1976-77. This review includes: (1) bacterial pathogens in animals; and (2) detection and identification of waterborne bacterial pathogens. A list of 129 references is also presented. (HM)
USDA-ARS?s Scientific Manuscript database
Quantitative microbial risk assessment (QMRA) is a valuable complement to epidemiology for understanding the health impacts of waterborne pathogens. The approach works by extrapolating available data in two ways. First, dose-response data are typically extrapolated from feeding studies, which use ...
This ongoing project involves the development, validation and pilot application of a multiplex immunoassay based on Luminex microsphere technology to measure salivary antibody responses to the potentially-waterborne pathogens, noroviruses (Norwalk, VA387 and VA207), rotaviruses, ...
Making hospital water safe, examined.
Pearson, Susan
2011-01-01
What are the best methods for monitoring hospital water systems to prevent contamination by waterborne pathogens such as Pseudomonas aeruginosa and Legionella? How can hospital staff determine whether a Pseudomonas outbreak is due to cross-contamination between patients and staff, or to the contamination of a systemic water supply, and how can we best protect our most vulnerable patients from infection with the array of pathogenic organisms lurking in hospitals? As Susan Pearson reports, these were among the questions discussedby leading microbiologists at a recent one-day "waterborne infections" seminar organised by Pall Medical in Glasgow.
Hoyer, Andrea B; Schladow, S Geoffrey; Rueda, Francisco J
2015-10-15
Pathogen contamination of drinking water lakes and reservoirs is a severe threat to human health worldwide. A major source of pathogens in surface sources of drinking waters is from body-contact recreation in the water body. However, dispersion pathways of human waterborne pathogens from recreational beaches, where body-contact recreation is known to occur to drinking water intakes, and the associated risk of pathogens entering the drinking water supply remain largely undocumented. A high spatial resolution, three-dimensional hydrodynamic and particle tracking modeling approach has been developed to analyze the risk and mechanisms presented by pathogen dispersion. The pathogen model represents the processes of particle release, transport and survival. Here survival is a function of both water temperature and cumulative exposure to ultraviolet (UV) radiation. Pathogen transport is simulated using a novel and computationally efficient technique of tracking particle trajectories backwards, from a drinking water intake toward their source areas. The model has been applied to a large, alpine lake - Lake Tahoe, CA-NV (USA). The dispersion model results reveal that for this particular lake (1) the risk of human waterborne pathogens to enter drinking water intakes is low, but significant; (2) this risk is strongly related to the depth of the thermocline in relation to the depth of the intake; (3) the risk increases with the seasonal deepening of the surface mixed layer; and (4) the risk increases at night when the surface mixed layer deepens through convective mixing and inactivation by UV radiation is eliminated. While these risk factors will quantitatively vary in different lakes, these same mechanisms will govern the process of transport of pathogens. Copyright © 2015 Elsevier Ltd. All rights reserved.
Pathogens in drinking water: Are there any new ones
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reasoner, D.J.
1993-01-01
Since 1976 three newly recognized human pathogens have become familiar to the drinking water industry as waterborne disease agents. These are: the legionnaires disease agent, Legionella pneumophila and related species; and two protozoan pathogens, Giardia lamblia and Cryptosporidium parvum, both of which form highly disinfectant resistant cysts that are shed in the feces of infected individuals. The question frequently arises - are there other emerging waterborne pathogens that may pose a human health problem that the drinking water industry will have to deal with. The paper will review the current state of knowledge of the occurrence and incidence of pathogensmore » and opportunistic pathogens other than Legionella, Giardia and Cryptosporidium in treated and untreated drinking water. Bacterial agents that will be reviewed include Aeromonas, Pseudomonas, Campylobacter, Mycobacterium, Yersinia and Plesiomonas. Aspects of detection of these agents including detection methods and feasibility of monitoring will be addressed.« less
Recent developments in detection and enumeration of waterborne bacteria: a retrospective minireview.
Deshmukh, Rehan A; Joshi, Kopal; Bhand, Sunil; Roy, Utpal
2016-12-01
Waterborne diseases have emerged as global health problems and their rapid and sensitive detection in environmental water samples is of great importance. Bacterial identification and enumeration in water samples is significant as it helps to maintain safe drinking water for public consumption. Culture-based methods are laborious, time-consuming, and yield false-positive results, whereas viable but nonculturable (VBNCs) microorganisms cannot be recovered. Hence, numerous methods have been developed for rapid detection and quantification of waterborne pathogenic bacteria in water. These rapid methods can be classified into nucleic acid-based, immunology-based, and biosensor-based detection methods. This review summarizes the principle and current state of rapid methods for the monitoring and detection of waterborne bacterial pathogens. Rapid methods outlined are polymerase chain reaction (PCR), digital droplet PCR, real-time PCR, multiplex PCR, DNA microarray, Next-generation sequencing (pyrosequencing, Illumina technology and genomics), and fluorescence in situ hybridization that are categorized as nucleic acid-based methods. Enzyme-linked immunosorbent assay (ELISA) and immunofluorescence are classified into immunology-based methods. Optical, electrochemical, and mass-based biosensors are grouped into biosensor-based methods. Overall, these methods are sensitive, specific, time-effective, and important in prevention and diagnosis of waterborne bacterial diseases. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.
Graczyk, Thaddeus K; Sunderland, Deirdre; Awantang, Grace N; Mashinski, Yessika; Lucy, Frances E; Graczyk, Zofi; Chomicz, Lidia; Breysse, Patrick N
2010-04-01
During summer months, samples of marine beach water were tested weekly for human waterborne pathogens in association with high and low bather numbers during weekends and weekdays, respectively. The numbers of bathers on weekends were significantly higher than on weekdays (P < 0.001), and this was associated with a significant (P < 0.04) increase in water turbidity. The proportion of water samples containing Cryptosporidium parvum, Giardia duodenalis, and Enterocytozoon bieneusi was significantly higher (P < 0.03) on weekends than on weekdays, and significantly (P < 0.01) correlated with enterococci counts. The concentration of all three waterborne pathogens was significantly correlated with bather density (P < 0.01). The study demonstrated that: (a) human pathogens were present in beach water on days deemed acceptable for bathing according to fecal bacterial standards; (b) enterococci count was a good indicator for the presence of Cryptosporidium, Giardia, and microsporidian spores in recreational marine beach water; (c) water should be tested for enterococci during times when bather numbers are high; (d) re-suspension of bottom sediments by bathers caused elevated levels of enterococci and waterborne parasites, thus bathers themselves can create a non-point source for water contamination; and (e) exposure to recreational bathing waters can play a role in epidemiology of microsporidiosis. In order to protect public health, it is recommended to: (a) prevent diapered children from entering beach water; (b) introduce bather number limits to recreational areas; (c) advise people with gastroenteritis to avoid bathing; and (d) use showers prior to and after bathing.
Environmental waters are important reservoirs of pathogenic microorganisms, many of which are of fecal origin. In most cases, the presence of pathogens is determined using surrogate bacterial indicators. In other cases, direct detection of the pathogen in question is required. M...
A microfluidic laser scattering sensor for label-free detection of waterborne pathogens
NASA Astrophysics Data System (ADS)
Wei, Huang; Yang, Limei; Li, Feng
2016-10-01
A microfluidic-based multi-angle laser scattering (MALS) sensor capable of acquiring scattering pattern of single particle is demonstrated. The size and relative refractive index (RI) of polystyrene (PS) microspheres were deduced with accuracies of 60 nm and 0.001 by analyzing the scattering patterns. We measured scattering patterns of waterborne parasites i.e., cryptosporidium parvum (c.parvum) and giardia lamblia (g.lamblia), and some other representative species in 1 L water within 1 hour, and the waterborne parasites were identified with accuracy better than 96% by classification of distinctive scattering patterns with a support-vector-machine (SVM) algorithm. The system provides a promising tool for label-free and rapid detection of waterborne parasites.
Microfluidics for effective concentration and sorting of waterborne protozoan pathogens.
Jimenez, M; Bridle, H
2016-07-01
We report on an inertial focussing based microfluidics technology for concentrating waterborne protozoa, achieving a 96% recovery rate of Cryptosporidium parvum and 86% for Giardia lamblia at a throughput (mL/min) capable of replacing centrifugation. The approach can easily be extended to other parasites and also bacteria. Copyright © 2016 Elsevier B.V. All rights reserved.
Climate change impacts on faecal indicator and waterborne pathogen concentrations and disease
NASA Astrophysics Data System (ADS)
Hofstra, Nynke; Vermeulen, Lucie C.; Wondmagegn, Berhanu Y.
2013-04-01
Changes in temperature and precipitation patterns may impact on the concentrations of the faecal indicator E. coli and waterborne pathogens, such as Cryptosporidium, in the surface water, and consequently - through drinking water, recreational water or consumption of irrigated vegetables - on the risk of waterborne disease. Although an increased temperature would generally increase the decline of pathogens and therefore decrease the surface water concentrations, increased precipitation and an increased incidence of extreme precipitation may increase surface water concentrations through increased (sub-)surface runoff and an increased risk of sewer overflows. And while the diluting effect of increased precipitation decreases the surface water concentration, decreased precipitation increases the percentage of sewage in the surface water and therefore increases the concentration. Moreover, (extreme) precipitation after drought may also increase the concentration. Changes in behaviour, such as increased recreation and irrigation with higher temperatures may impact on the disease risk. What the balance is between these positive and negative impacts of climate change on faecal indicator and waterborne pathogen concentrations and disease is not well known yet. A lack of available statistical or process-based models and suitable scenarios prevents quantitative analyses. We will present two examples of recent studies that aim to assess the impact of climate change on faecal indicator concentrations and waterborne disease. The first is a study on the relationship between climate variables and E. coli concentrations in the water of river systems in the Netherlands for the period 1985 - 2010. This study shows that each of the variables water temperature (negatively), precipitation and discharge (both positively) are significantly correlated with E. coli concentrations for most measurement locations. We will also present a linear regression model, including all of these variables. In the second example we assess the relationship between the weather variables precipitation and minimum and maximum temperature and the number of diarrhoeal cases in Ethiopia. We have digitised data from the Ethiopian health service and hospitals on the number of diarrhoeal cases for the period 2005 - 2010 and used meteorological data from their weather service. Very strong correlations can be found between the monthly weather variables and the number of diarrhoeal cases and a linear regression model including all variables explains a large part of the variability of the data. The studies indicate that climate change may increase the waterborne pathogen concentration in surface water and disease risk and should therefore not be ignored as a threat to microbial water quality.
Helicobacter pylori is a pathogenic bacteria which inhabits the human stomach and upper gastrointestinal tract. This encyclopedic entry summarizes the potential role of this organism as a waterborne pathogen. Information is provided on the physiology and morphology of this bacter...
Development and validation of same-day monitoring methods for recreational water
When water is polluted, swimmers can become ill from exposure to waterborne pathogens. EPA scientists have developed a new DNA extraction method for determining the amount of pathogens present in water.
The primary goal of the disinfection process in drinking water treatment is the inactivation of microbial pathogens. These pathogens comprise a diverse group of organisms which serve as the etiological agents of waterborne disease. Included in this group are bacterial, viral and ...
USDA-ARS?s Scientific Manuscript database
Waterborne pathogens were detected in 96% of samples collected at three Lake Michigan beaches during the summer of 2010. Linear regression models were developed to explore environmental factors that may be influential for pathogen prevalence. Simulation of pathogen concentration using these models, ...
Legionella - (re-)awakening to the Amoeba-based Pathogens of Distribution System Biofilm
Fecal pathogens have long been the focus of concern in the distribution of drinking waters. Yet today, with distribution system ‘failures’ accounting for the majority of waterborne outbreaks in the USA, there is growing realization that pathogens endemic to aquatic biofilms may a...
DISINFECTION OF EMERGING PATHOGENS
There is a growing awareness of the need to control waterborne microbial pathogens. This presentation will concentate on the role of chemical inactivation, using chlorine, chloramines and ozone as a means of controlling bacterial and protozoan species. Information will be present...
NASA Astrophysics Data System (ADS)
Harter, T.; Li, X.; Atwill, E. R.; Packman, A. I.
2015-12-01
Several surveys of microbial indicators and pathogens were conducted to determine the impact of confined animal farming operations (CAFOs) on shallow, local, and regional groundwater quality in the Central Valley aquifer system, California. The aquifer system consists of highly heterogeneous, alluvial, unconsolidated coarse- to fine-grained sediments and is among the largest aquifers in the U.S.. Overlying landuse includes 3 million ha of irrigated agriculture and 1.7 million mature dairy cows in nearly 1,500 CAFOs. A multi-scale survey of water-borne indicator pathogens (Enterococcus spp. and generic E. coli) and of three water-borne pathogens (Campylobacter, Salmonella, and E. coli O157:H7) was conducted at five different spatial scales, increasing with distance from animal sources of these enteric microbial organisms: moist surfaces within individual CAFO sub-systems (calf-hutches, heifer corrals, mature cow stalls, hospital barn etc.), first encountered (shallow) groundwater immediately below these sub-systems, production aquifer below CAFOs, production aquifer near CAFOs, and production aquifer away from CAFOs. Where found, indicator pathogens were tested for antibiotic resistance. Hundreds of samples were collected at each scale: continuously during irrigation events and seasonally over a multi-year period at the three smaller site-scales; and in a one-time survey at the two larger, regional scales. All three pathogens were frequently detected in moist surface samples across CAFO sub-systems, albeit at concentrations several orders of magnitude lower than enteric indicators. Two of the three pathogens (but not Campylobacter) were also detected in first encountered groundwater, at 3-9 m below ground surface, in 1% of samples. No pathogens were found at the production aquifer scales. Generic E. coli was detected in ¼ of first encountered groundwater samples, and in 4% of production aquifer samples, while Enterococcus spp. was ubiquitously present across the three site scales on CAFOs and in ¼ of production aquifer samples near and away from CAFOs. Two thirds of E. coli and five in six Enterococcus exhibited resistance to multiple (> 2) antibiotics. Field monitoring results are consistent with fate and transport modeling that accounts for heterogeneity in aquifer systems.
Background/Question/Methods: Runoff from agricultural fields undergoing manure applications or housing livestock operations may carry a variety of chemical and microbial contaminants that compromise water quality and increase the possibility of human exposure to pathogenic microo...
QUANTITATIVE ASSESSMENT OF PATHOGENS IN DRINKING WATER
The project has been summarized in a series of peer-reviewed published papers as outlined in the Publication section of this report. Pathogens capable of causing waterborne diseases include bacteria, protozoa, and viruses. Fecal indicator bacteria are the primary microorganisms u...
MANAGING WATERBORNE PATHOGENS ASSOCIATED WITH CONCENTRATED ANIMAL FEEDING OPERATIONS
Pathogenic microorganisms of fecal origin are the leading cause of river and stream impairments in the United States. Runoff from agricultural operations, particularly animal agricultural, can be a major contributor of fecal microbial pollution in a watershed. Several management...
THE SIGNIFICANCE OF ENTERIC VIRUSES AND WATERBORNE ILLNESS
With growing concern over drinking water safety, considerable attention has been directed towards microbial pathogens in source waters, and the adequacy of current methods used to detect, monitor and treat for these pathogens. The focus has been on bacterial and protozoan pathog...
Rundell, Mark S; Pingle, Maneesh; Das, Sanchita; Hussain, Aashiq; Ocheretina, Oksana; Charles, Macarthur; Larone, Davise H; Spitzer, Eric D; Golightly, Linnie; Barany, Francis
2014-06-01
Enteric pathogens that cause gastroenteritis remain a major global health concern. The goal of this study was to develop a multiplex PCR/ligation detection reaction (LDR) assay for the detection of all NIAID category B bacterial food and water-borne pathogens directly from stool specimens. To validate the PCR/LDR assay, clinical isolates of Campylobacter spp., Vibrio spp., Shigella spp., Salmonella spp., Listeria monocytogenes, Yersinia enterocolitica, and diarrheagenic Escherichia coli were tested. The sensitivity and specificity of the assay were assessed using a large number of seeded culture-negative stool specimens and a smaller set of clinical specimens from Haiti. The overall sensitivity ranged from 91% to 100% (median 100%) depending on the species. For the majority of organisms, the sensitivity was 100%. The overall specificity based on initial testing ranged from 98% to 100% depending on the species. After additional testing of discordant samples, the lowest specificity was 99.4%. PCR/LDR detected additional category B agents (particularly diarrheagenic E. coli) in 11/40 specimens from Haiti that were culture-positive for V. cholerae and in approximately 1% of routine culture-negative stool specimens from a hospital in New York. This study demonstrated the ability of the PCR/LDR assay to detect a large comprehensive panel of category B enteric bacterial pathogens as well as mixed infections. This type of assay has the potential to provide earlier warnings of possible public health threats and more accurate surveillance of food and water-borne pathogens. Copyright © 2014 Elsevier Inc. All rights reserved.
Rundell, Mark S.; Pingle, Maneesh; Das, Sanchita; Hussain, Aashiq; Ocheretina, Oksana; Charles, Macarthur; Larone, Davise H.; Spitzer, Eric D.; Golightly, Linnie; Barany, Francis
2014-01-01
Enteric pathogens that cause gastroenteritis remain a major global health concern. The goal of this study was to develop a multiplex PCR/LDR assay for the detection of all NIAID category B bacterial food and water-borne pathogens directly from stool specimens. To validate the PCR/LDR assay, clinical isolates of Campylobacter spp., Vibrio spp., Shigella spp., Salmonella spp., Listeria monocytogenes, Yersinia enterocolitica, and diarrheagenic Escherichia coli were tested. The sensitivity and specificity of the assay was assessed using a large number of seeded culture-negative stool specimens and a smaller set of clinical specimens from Haiti. The overall sensitivity ranged from 91 to 100% (median 100%) depending on the species. For the majority of organisms the sensitivity was 100%. The overall specificity based on initial testing ranged from 98% to 100% depending on the species. After additional testing of discordant samples the lowest specificity was 99.4%. PCR/LDR detected additional category B agents (particularly diarrheagenic E. coli) in 11/40 specimens from Haiti that were culture-positive for V. cholerae and in approximately 1% of routine culture-negative stool specimens from a hospital in New York. This study demonstrated the ability of the PCR/LDR assay to detect a large comprehensive panel of category B enteric bacterial pathogens as well as mixed infections. This type of assay has the potential to provide earlier warnings of possible public health threats and more accurate surveillance of food and water-borne pathogens. PMID:24709368
This paper describes the application and method performance parameters of a Luminex xMAP™ bead-based, multiplex immunoassay for measuring specific antibody responses in saliva samples (n=5438) to antigens of six common waterborne pathogens (Campylobacter jejuni, Helicobacter pylo...
Runoff from agricultural fields and urban landscapes may carry a variety of microbial contaminants that compromises water quality and increases the possibility of human exposure to pathogenic microorganisms. Establishing the relationship between microbial source tracking (MST) ma...
Ranking filter methods for concentrating pathogens in lake water
USDA-ARS?s Scientific Manuscript database
Accurately comparing filtration methods for concentrating waterborne pathogens is difficult because of two important water matrix effects on recovery measurements, the effect on PCR quantification and the effect on filter performance. Regarding the first effect, we show how to create a control water...
The Microbiological and Chemical Exposure Assessment Research Division of the EPA Office of Research and Development's National Exposure Research Laboratory has a robust in-house research program aimed at developing better occurrence and exposure methods for waterborne pathogens....
Next generation sequencing of oomycete communities in nursery irrigation water
Joyce Eberhart; Fumiaki Funahashi; Zachary S.L. Foster; Jennifer Parke
2017-01-01
Horticultural nurseries are under increasing pressure to reduce, remediate, and recycle irrigation water. A major constraint for reusing irrigation water is contamination by waterborne plant pathogenic Phytophthora and Pythium species. Current research is focused on helping plant nurseries monitor oomycete pathogens in...
Significance of Viable but Nonculturable Escherichia coli: Induction, Detection, and Control.
Ding, Tian; Suo, Yuanjie; Xiang, Qisen; Zhao, Xihong; Chen, Shiguo; Ye, Xingqian; Liu, Donghong
2017-03-28
Diseases caused by foodborne or waterborne pathogens are emerging. Many pathogens can enter into the viable but nonculturable (VBNC) state, which is a survival strategy when exposed to harsh environmental stresses. Pathogens in the VBNC state have the ability to evade conventional microbiological detection methods, posing a significant and potential health risk. Therefore, controlling VBNC bacteria in food processing and the environment is of great importance. As the typical one of the gram-negatives, Escherichia coli ( E. coli ) is a widespread foodborne and waterborne pathogenic bacterium and is able to enter into a VBNC state in extreme conditions (similar to the other gram-negative bacteria), including inducing factors and resuscitation stimulus. VBNC E. coli has the ability to recover both culturability and pathogenicity, which may bring potential health risk. This review describes the concrete factors (nonthermal treatment, chemical agents, and environmental factors) that induce E. coli into the VBNC state, the condition or stimulus required for resuscitation of VBNC E. coli , and the methods for detecting VBNC E. coli . Furthermore, the mechanism of genes and proteins involved in the VBNC E. coli is also discussed in this review.
Legionella and Mycobacterium Occurrence/Persistence in Homes and Office Buildings
Legionella and non-tuberculous Mycobacterium species are two of the more important environmental pathogens that cause human health effects. They contribute to the highest economic burden and one of the heaviest disease burdens of all of the waterborne pathogens that pose a risk t...
A Customized DNA Microarray for Microbial Source Tracking in Environmental Systems
It is estimated that more than 160, 000 miles of rivers and streams in the United States are impaired due to the presence of waterborne pathogens. These pathogens typically originate from human and other animal fecal pollution sources; therefore, a rapid microbial source tracking...
Common Features of Opportunistic Premise Plumbing Pathogens
Falkinham, Joseph O.
2015-01-01
Recently it has been estimated that the annual cost of diseases caused by the waterborne pathogens Legionella pneumonia, Mycobacterium avium, and Pseudomonas aeruginosa is $500 million. For the period 2001–2012, the estimated cost of hospital admissions for nontuberculous mycobacterial pulmonary disease, the majority caused by M. avium, was almost $1 billion. These three waterborne opportunistic pathogens are normal inhabitants of drinking water—not contaminants—that share a number of key characteristics that predispose them to survival, persistence, and growth in drinking water distribution systems and premise plumbing. Herein, I list and describe these shared characteristics that include: disinfectant-resistance, biofilm-formation, growth in amoebae, growth at low organic carbon concentrations (oligotrophic), and growth under conditions of stagnation. This review is intended to increase awareness of OPPPs, identify emerging OPPPs, and challenge the drinking water industry to develop novel approaches toward their control. PMID:25918909
Baron, Julianne L; Peters, Tammy; Shafer, Raymond; MacMurray, Brian; Stout, Janet E
2014-11-01
Opportunistic waterborne pathogens (eg, Legionella, Pseudomonas) may persist in water distribution systems despite municipal chlorination and secondary disinfection and can cause health care-acquired infections. Point-of-use (POU) filtration can limit exposure to pathogens; however, their short maximum lifetime and membrane clogging have limited their use. A new faucet filter rated at 62 days was evaluated at a cancer center in Northwestern Pennsylvania. Five sinks were equipped with filters, and 5 sinks served as controls. Hot water was collected weekly for 17 weeks and cultured for Legionella, Pseudomonas, and total bacteria. Legionella was removed from all filtered samples for 12 weeks. One colony was recovered from 1 site at 13 weeks; however, subsequent tests were negative through 17 weeks of testing. Total bacteria were excluded for the first 2 weeks, followed by an average of 1.86 log reduction in total bacteria compared with controls. No Pseudomonas was recovered from filtered or control faucets. This next generation faucet filter eliminated Legionella beyond the 62 day manufacturers' recommended maximum duration of use. These new POU filters will require fewer change-outs than standard filters and could be a cost-effective method for preventing exposure to Legionella and other opportunistic waterborne pathogens in hospitals with high-risk patients. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
[Diseases transmitted through water for human consumption].
Franco, E; Dentamaro, M
2003-01-01
The water for human consumption maintains a biological risk and can transmit diseases. The classical waterborne and the presently frequent diseases caused by protozoi Giardia and Cryptosporidium are considered and Arcobacter butzleri, a new waterborne pathogen, is described. Many measures have been adopted by institutions to ensure the quality of the drinking water. Managers and public health operators is working in order to verify the efficiency of more suitable indicators for its monitoring.
Microbial risk assessment (MRA) in the food industry is used to support HACCP – which largely focuses on bacterial pathogen control in processing foodstuffs Potential role of microbially-contaminated water used in food production is not as well understood Emergence...
Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy. Pathogen-specific antibodies in saliva can be used as bioindicators of recent or ongoing infection. Because collection of saliva is easy and painless, i...
Fundamentals, achievements and challenges in the electrochemical sensing of pathogens.
Monzó, Javier; Insua, Ignacio; Fernandez-Trillo, Francisco; Rodriguez, Paramaconi
2015-11-07
Electrochemical sensors are powerful tools widely used in industrial, environmental and medical applications. The versatility of electrochemical methods allows for the investigation of chemical composition in real time and in situ. Electrochemical detection of specific biological molecules is a powerful means for detecting disease-related markers. In the last 10 years, highly-sensitive and specific methods have been developed to detect waterborne and foodborne pathogens. In this review, we classify the different electrochemical techniques used for the qualitative and quantitative detection of pathogens. The robustness of electrochemical methods allows for accurate detection even in heterogeneous and impure samples. We present a fundamental description of the three major electrochemical sensing methods used in the detection of pathogens and the advantages and disadvantages of each of these methods. In each section, we highlight recent breakthroughs, including the utilisation of microfluidics, immunomagnetic separation and multiplexing for the detection of multiple pathogens in a single device. We also include recent studies describing new strategies for the design of future immunosensing systems and protocols. The high sensitivity and selectivity, together with the portability and the cost-effectiveness of the instrumentation, enhances the demand for further development in the electrochemical detection of microbes.
Workshop focuses on study of climate's effects on health
NASA Astrophysics Data System (ADS)
Diaz, Henry F.; Epstein, Paul R.; Aron, Joan L.; Confalonieri, Ulisses E. C.
Changes in temperature, precipitation, humidity, and storm patterns influence upsurges of waterborne diseases such as hepatitis, shigella dysentery, typhoid, and cholera as well as vector-borne pathogens such as malaria, dengue, yellow fever, encephalitis, schistosomiasis, plague, and hantavirus. Cycles of flooding and drought directly affect factors such as the multiplication rates of disease vectors, the biting rate of vectors, and the amount of host-vector interaction. Indirectly, climate influences parameters important to vector spread or survival such as agricultural practices, the disruption of ecosystems, or changes in social systems and practices, which in turn change the relationship between the parasite, the vector, its predators, and the host.
Spatial variation in disease resistance: from molecules to metapopulations
Laine, Anna-Liisa; Burdon, Jeremy J.; Dodds, Peter N.; Thrall, Peter H.
2010-01-01
Summary Variation in disease resistance is a widespread phenomenon in wild plant-pathogen associations. Here, we review current literature on natural plant-pathogen associations to determine how diversity in disease resistance is distributed at different hierarchical levels – within host individuals, within host populations, among host populations at the metapopulation scale and at larger regional scales. We find diversity in resistance across all spatial scales examined. Furthermore, variability seems to be the best counter-defence of plants against their rapidly evolving pathogens. We find that higher diversity of resistance phenotypes also results in higher levels of resistance at the population level. Overall, we find that wild plant populations are more likely to be susceptible than resistant to their pathogens. However, the degree of resistance differs strikingly depending on the origin of the pathogen strains used in experimental inoculation studies. Plant populations are on average 16% more resistant to allopatric pathogen strains than they are to strains that occur within the same population (48 % vs. 32 % respectively). Pathogen dispersal mode affects levels of resistance in natural plant populations with lowest levels detected for hosts of airborne pathogens and highest for waterborne pathogens. Detailed analysis of two model systems, Linum marginale infected by Melampsora lini, and Plantago lanceolata infected by Podosphaera plantaginis, show that the amount of variation in disease resistance declines towards higher spatial scales as we move from individual hosts to metapopulations, but evaluation of multiple spatial scales is needed to fully capture the structure of disease resistance. Synthesis: Variation in disease resistance is ubiquitous in wild plant-pathogen associations. While the debate over whether the resistance structure of plant populations is determined by pathogen-imposed selection versus non-adaptive processes remains unresolved, we do report examples of pathogen-imposed selection on host resistance. Here we highlight the importance of measuring resistance across multiple spatial scales, and of using sympatric strains when looking for signs of coevolution in wild plant-pathogen interactions. PMID:21243068
2012-04-01
attack), the spread of waterborne pathogens (e.g. typhoid fever ) and airborne pathogens (e.g. avian flu, Severe Acute Respiratory Syndromes, and...hemorrhagic fever with fatality in humans ranging from 50-89% (Biosafety level 4) (Brion and Silverstein, 1999). If one aggregate of ebola viruses
A review of outbreaks of waterborne disease associated with ships: evidence for risk management.
Rooney, Roisin M.; Bartram, Jamie K.; Cramer, Elaine H.; Mantha, Stacey; Nichols, Gordon; Suraj, Rohini; Todd, Ewen C. D.
2004-01-01
OBJECTIVE: The organization of water supply to and on ships differs considerably from that of water supply on land. Risks of contamination can arise from source water at the port or during loading, storage, or distribution on the ship. The purpose of this article is to review documented outbreaks of waterborne diseases associated with passenger, cargo, fishing, and naval ships to identify contributing factors so that similar outbreaks can be prevented in the future. METHODS: The authors reviewed 21 reported outbreaks of waterborne diseases associated with ships. For each outbreak, data on pathogens/toxins, type of ship, factors contributing to outbreaks, mortality and morbidity, and remedial action are presented. RESULTS: The findings of this review show that the majority of reported outbreaks were associated with passenger ships and that more than 6,400 people were affected. Waterborne outbreaks due to Enterotoxigenic Escherichia coli, noroviruses, Salmonella spp, Shigella sp, Cryptosporidium sp, and Giardia lamblia occurred on ships. Enterotoxigenic E. coli was the pathogen most frequently associated with outbreaks. One outbreak of chemical water poisoning also occurred on a ship. Risk factors included contaminated port water, inadequate treatment, improper loading techniques, poor design and maintenance of storage tanks, ingress of contamination during repair and maintenance, cross-connections, back siphonage, and insufficient residual disinfectant. CONCLUSIONS: Waterborne disease outbreaks on ships can be prevented. The factors contributing to outbreaks emphasize the need for hygienic handling of water along the supply chain from source to consumption. A comprehensive approach to water safety on ships is essential. This may be achieved by the adoption of Water Safety Plans that cover design, construction, operation, and routine inspection and maintenance. PMID:15219801
A review of outbreaks of waterborne disease associated with ships: evidence for risk management.
Rooney, Roisin M; Bartram, Jamie K; Cramer, Elaine H; Mantha, Stacey; Nichols, Gordon; Suraj, Rohini; Todd, Ewen C D
2004-01-01
The organization of water supply to and on ships differs considerably from that of water supply on land. Risks of contamination can arise from source water at the port or during loading, storage, or distribution on the ship. The purpose of this article is to review documented outbreaks of waterborne diseases associated with passenger, cargo, fishing, and naval ships to identify contributing factors so that similar outbreaks can be prevented in the future. The authors reviewed 21 reported outbreaks of waterborne diseases associated with ships. For each outbreak, data on pathogens/toxins, type of ship, factors contributing to outbreaks, mortality and morbidity, and remedial action are presented. The findings of this review show that the majority of reported outbreaks were associated with passenger ships and that more than 6,400 people were affected. Waterborne outbreaks due to Enterotoxigenic Escherichia coli, noroviruses, Salmonella spp, Shigella sp, Cryptosporidium sp, and Giardia lamblia occurred on ships. Enterotoxigenic E. coli was the pathogen most frequently associated with outbreaks. One outbreak of chemical water poisoning also occurred on a ship. Risk factors included contaminated port water, inadequate treatment, improper loading techniques, poor design and maintenance of storage tanks, ingress of contamination during repair and maintenance, cross-connections, back siphonage, and insufficient residual disinfectant. Waterborne disease outbreaks on ships can be prevented. The factors contributing to outbreaks emphasize the need for hygienic handling of water along the supply chain from source to consumption. A comprehensive approach to water safety on ships is essential. This may be achieved by the adoption of Water Safety Plans that cover design, construction, operation, and routine inspection and maintenance.
A practical approach to ensuring safe water.
Pearson, Susan
2012-08-01
Susan Pearson BSc reports on a recent specialist waterborne diseases 'masterclass' held in Nottingham, at which leading experts discussed not only the control of Pseudomonas, but also other problematic waterborne pathogens such as Legionella, the cause of Legionnaires' disease. The Pall Medical-sponsored event provided plenty of 'food for thought' for estates and facilities personnel responsible for hospital water systems, and clearly demonstrated how difficult and persistent a foe organisms such as Pseudomonas aeruginosa and Legionella pneumophila, which, if left unchecked, pose significant patient health risks, can be.
Occurrence and Control of Tularemia in Drinking Water ...
Journal Article This review article will focus on tularemia acquired from contaminated drinking water and the adequacy of control measures for preventing waterborne transmission. Contaminated drinking water can serve as a vehicle for the spread of tularemia. Disease occurrence has been most commonly associated with untreated community and domestic water supplies. F. tularensis is of interest both from the standpoint of natural occurring waterborne outbreaks and in regards to its potential use as a bio-threat organism. The organism can persist in the aquatic environment and methods exist for detection in water. While capable of being inactivated by commonly used drinking water disinfectants, F. tularensis does exhibit an increased resistance to chlorination in comparison to other waterborne vegetative bacterial pathogens.
Jalava, Katri; Rintala, Hanna; Ollgren, Jukka; Maunula, Leena; Gomez-Alvarez, Vicente; Revez, Joana; Palander, Marja; Antikainen, Jenni; Kauppinen, Ari; Räsänen, Pia; Siponen, Sallamaari; Nyholm, Outi; Kyyhkynen, Aino; Hakkarainen, Sirpa; Merentie, Juhani; Pärnänen, Martti; Loginov, Raisa; Ryu, Hodon; Kuusi, Markku; Siitonen, Anja; Miettinen, Ilkka; Santo Domingo, Jorge W; Hänninen, Marja-Liisa; Pitkänen, Tarja
2014-01-01
Failures in the drinking water distribution system cause gastrointestinal outbreaks with multiple pathogens. A water distribution pipe breakage caused a community-wide waterborne outbreak in Vuorela, Finland, July 2012. We investigated this outbreak with advanced epidemiological and microbiological methods. A total of 473/2931 inhabitants (16%) responded to a web-based questionnaire. Water and patient samples were subjected to analysis of multiple microbial targets, molecular typing and microbial community analysis. Spatial analysis on the water distribution network was done and we applied a spatial logistic regression model. The course of the illness was mild. Drinking untreated tap water from the defined outbreak area was significantly associated with illness (RR 5.6, 95% CI 1.9-16.4) increasing in a dose response manner. The closer a person lived to the water distribution breakage point, the higher the risk of becoming ill. Sapovirus, enterovirus, single Campylobacter jejuni and EHEC O157:H7 findings as well as virulence genes for EPEC, EAEC and EHEC pathogroups were detected by molecular or culture methods from the faecal samples of the patients. EPEC, EAEC and EHEC virulence genes and faecal indicator bacteria were also detected in water samples. Microbial community sequencing of contaminated tap water revealed abundance of Arcobacter species. The polyphasic approach improved the understanding of the source of the infections, and aided to define the extent and magnitude of this outbreak.
Bed sediments of streams and rivers may store high concentrations of fecal indicator bacteria (FIB) and pathogens. Due to resuspension events, these contaminants can be mobilized into the water column and affect overall water quality. Other bacterial indicators such as microbial ...
NASA Astrophysics Data System (ADS)
Ceylan Koydemir, Hatice; Feng, Steve; Liang, Kyle; Nadkarni, Rohan; Benien, Parul; Ozcan, Aydogan
2017-06-01
Giardia lamblia is a waterborne parasite that affects millions of people every year worldwide, causing a diarrheal illness known as giardiasis. Timely detection of the presence of the cysts of this parasite in drinking water is important to prevent the spread of the disease, especially in resource-limited settings. Here we provide extended experimental testing and evaluation of the performance and repeatability of a field-portable and cost-effective microscopy platform for automated detection and counting of Giardia cysts in water samples, including tap water, non-potable water, and pond water. This compact platform is based on our previous work, and is composed of a smartphone-based fluorescence microscope, a disposable sample processing cassette, and a custom-developed smartphone application. Our mobile phone microscope has a large field of view of 0.8 cm2 and weighs only 180 g, excluding the phone. A custom-developed smartphone application provides a user-friendly graphical interface, guiding the users to capture a fluorescence image of the sample filter membrane and analyze it automatically at our servers using an image processing algorithm and training data, consisting of >30,000 images of cysts and >100,000 images of other fluorescent particles that are captured, including, e.g. dust. The total time that it takes from sample preparation to automated cyst counting is less than an hour for each 10 ml of water sample that is tested. We compared the sensitivity and the specificity of our platform using multiple supervised classification models, including support vector machines and nearest neighbors, and demonstrated that a bootstrap aggregating (i.e. bagging) approach using raw image file format provides the best performance for automated detection of Giardia cysts. We evaluated the performance of this machine learning enabled pathogen detection device with water samples taken from different sources (e.g. tap water, non-potable water, pond water) and achieved a limit of detection of 12 cysts per 10 ml, an average cyst capture efficiency of 79%, and an accuracy of 95%. Providing rapid detection and quantification of waterborne pathogens without the need for a microbiology expert, this field-portable imaging and sensing platform running on a smartphone could be very useful for water quality monitoring in resource-limited settings.
Epidemicity thresholds for water-borne and water-related diseases.
Mari, Lorenzo; Casagrandi, Renato; Rinaldo, Andrea; Gatto, Marino
2018-06-14
Determining the conditions that favor pathogen establishment in a host community is key to disease control and eradication. However, focusing on long-term dynamics alone may lead to an underestimation of the threats imposed by outbreaks triggered by short-term transient phenomena. Achieving an effective epidemiological response thus requires to look at different timescales, each of which may be endowed with specific management objectives. In this work we aim to determine epidemicity thresholds for some prototypical examples of water-borne and water-related diseases, a diverse family of infections transmitted either directly through water infested with pathogens or by vectors whose lifecycles are closely associated with water. From a technical perspective, while conditions for endemicity are determined via stability analysis, epidemicity thresholds are defined through generalized reactivity analysis, a recently proposed method that allows the study of the short-term instability properties of ecological systems. Understanding the drivers of water-borne and water-related disease dynamics over timescales that may be relevant to epidemic and/or endemic transmission is a challenge of the utmost importance, as large portions of the developing world are still struggling with the burden imposed by these infections. Copyright © 2018 Elsevier Ltd. All rights reserved.
Effects of Chlorine on Enterovirus RNA Degradation
The primary mechanism of disinfection of waterborne pathogens by chlorine has always been believed to be due to the alteration of proteins by free chlorine and subsequent disruption of their biological structure.
Knowledge Mapping for Climate Change and Food- and Waterborne Diseases.
Semenza, Jan C; Höuser, Christoph; Herbst, Susanne; Rechenburg, Andrea; Suk, Jonathan E; Frechen, Tobias; Kistemann, Thomas
2012-02-01
The authors extracted from the PubMed and ScienceDirect bibliographic databases all articles published between 1998 and 2009 that were relevant to climate change and food- and waterborne diseases. Any material within each article that provided information about a relevant pathogen and its relationship with climate and climate change was summarized as a key fact, entered into a relational knowledge base, and tagged with the terminology (predefined terms) used in the field. These terms were organized, quantified, and mapped according to predefined hierarchical categories. For noncholera Vibrio sp. and Cryptosporidium sp., data on climatic and environmental influences (52% and 49% of the total number of key facts, respectively) pertained to specific weather phenomena (as opposed to climate change phenomena) and environmental determinants, whereas information on the potential effects of food-related determinants that might be related to climate or climate change were virtually absent. This proportion was lower for the other pathogens studied ( Campylobacter sp. 40%, Salmonella sp. 27%, Norovirus 25%, Listeria sp. 8%), but they all displayed a distinct concentration of information on general food-and water-related determinants or effects, albeit with little detail. Almost no information was available concerning the potential effects of changes in climatic variables on the pathogens evaluated, such as changes in air or water temperature, precipitation, humidity, UV radiation, wind, cloud coverage, sunshine hours, or seasonality. Frequency profiles revealed an abundance of data on weather and food-specific determinants, but also exposed extensive data deficiencies, particularly with regard to the potential effects of climate change on the pathogens evaluated. A reprioritization of public health research is warranted to ensure that funding is dedicated to explicitly studying the effects of changes in climate variables on food- and waterborne diseases.
Knowledge Mapping for Climate Change and Food- and Waterborne Diseases
Semenza, Jan C.; Höuser, Christoph; Herbst, Susanne; Rechenburg, Andrea; Suk, Jonathan E.; Frechen, Tobias; Kistemann, Thomas
2011-01-01
The authors extracted from the PubMed and ScienceDirect bibliographic databases all articles published between 1998 and 2009 that were relevant to climate change and food- and waterborne diseases. Any material within each article that provided information about a relevant pathogen and its relationship with climate and climate change was summarized as a key fact, entered into a relational knowledge base, and tagged with the terminology (predefined terms) used in the field. These terms were organized, quantified, and mapped according to predefined hierarchical categories. For noncholera Vibrio sp. and Cryptosporidium sp., data on climatic and environmental influences (52% and 49% of the total number of key facts, respectively) pertained to specific weather phenomena (as opposed to climate change phenomena) and environmental determinants, whereas information on the potential effects of food-related determinants that might be related to climate or climate change were virtually absent. This proportion was lower for the other pathogens studied (Campylobacter sp. 40%, Salmonella sp. 27%, Norovirus 25%, Listeria sp. 8%), but they all displayed a distinct concentration of information on general food-and water-related determinants or effects, albeit with little detail. Almost no information was available concerning the potential effects of changes in climatic variables on the pathogens evaluated, such as changes in air or water temperature, precipitation, humidity, UV radiation, wind, cloud coverage, sunshine hours, or seasonality. Frequency profiles revealed an abundance of data on weather and food-specific determinants, but also exposed extensive data deficiencies, particularly with regard to the potential effects of climate change on the pathogens evaluated. A reprioritization of public health research is warranted to ensure that funding is dedicated to explicitly studying the effects of changes in climate variables on food- and waterborne diseases. PMID:24771989
Issues of the presence of parasitic protozoa in surface waters
NASA Astrophysics Data System (ADS)
Hawrylik, Eliza
2018-02-01
Parasitic protozoa are very numerous organisms in the environment that play an important role in the spread of water-borne diseases. Water-borne epidemics caused by parasitic protozoa are noted throughout the world. Within these organisms, intestinal protozoa of the genera Cryptosporidium and Giardia are ones of the most serious health hazards for humans. This paper focuses on the problem of the presence of parasitic protozoa in surface waters. Characteristics of the most frequently recognized pathogens responsible for water-borne outbreaks were described, as well as sources of contamination and surface waters contamination due to protozoa of the genus Cryptosporidium and Giardia were presented. The methods of destroying the cysts and oocysts of parasitic protozoa used nowadays in the world were also presented in a review.
Pathogenic agents in freshwater resources
NASA Astrophysics Data System (ADS)
Geldreich, Edwin E.
1996-02-01
Numerous pathogenic agents have been found in freshwaters used as sources for water supplies, recreational bathing and irrigation. These agents include bacterial pathogens, enteric viruses, several protozoans and parasitic worms more common to tropical waters. Although infected humans are a major source of pathogens, farm animals (cattle, sheep, pigs), animal pets (dogs, cats) and wildlife serve as significant reservoirs and should not be ignored. The range of infected individuals within a given warm-blooded animal group (humans included) may range from 1 to 25%. Survival times for pathogens in the water environment may range from a few days to as much as a year (Ascaris, Taenia eggs), with infective dose levels varying from one viable cell for several primary pathogenic agents to many thousands of cells for a given opportunistic pathogen.As pathogen detection in water is complex and not readily incorporated into routine monitoring, a surrogate is necessary. In general, indicators of faecal contamination provide a positive correlation with intestinal pathogen occurrences only when appropriate sample volumes are examined by sensitive methodology.Pathways by which pathogens reach susceptible water users include ingestion of contaminated water, body contact with polluted recreational waters and consumption of salad crops irrigated by polluted freshwaters. Major contributors to the spread of various water-borne pathogens are sewage, polluted surface waters and stormwater runoff. All of these contributions are intensified during periods of major floods. Several water-borne case histories are cited as examples of breakdowns in public health protection related to water supply, recreational waters and the consumption of contaminated salad crops. In the long term, water resource management must focus on pollution prevention from point sources of waste discharges and the spread of pathogens in watershed stormwater runoff.
Hospital water and opportunities for infection prevention
Decker, Brooke K.; Palmore, Tara N.
2017-01-01
Nosocomial waterborne pathogens may reach patients through several modes of transmission. Colonization of healthcare facility waterworks can occur in the proximal infrastructure, in the distal water outlets, or both. Infections with waterborne organisms such as Legionella, mycobacteria, Pseudomonas, and others cause significant morbidity and mortality, particularly in immunocomprised patients. Hospitals should have prospective water safety plans that include preventive measures, as prevention is preferable to remediation of contaminated hospital water distribution system. Whole genome sequencing may provide more informative epidemiologic data to link patient infections with hospital water isolates. PMID:25217106
Many waterborne pathogens originate in the gastrointestinal tract of humans or other animals (the primary habitat), and enter water bodies (secondary habitat) via direct fecal deposition, runoff, or sewage discharges. Fecal indicator bacteria (FIB) such as fecal coliforms, entero...
USDA-ARS?s Scientific Manuscript database
Bed sediments of streams and rivers may store high concentrations of fecal indicator bacteria (FIB) and pathogens. These contaminants can be mobilized into the water column due to resuspension events, thus affecting overall water quality. Along with the contaminants, other markers such as microbia...
Non-Cholera Vibrios: The Microbial Barometer of Climate Change.
Baker-Austin, Craig; Trinanes, Joaquin; Gonzalez-Escalona, Narjol; Martinez-Urtaza, Jaime
2017-01-01
There is a growing interest in the role of climate change in driving the spread of waterborne infectious diseases, such as those caused by bacterial pathogens. One particular group of pathogenic bacteria - vibrios - are a globally important cause of diseases in humans and aquatic animals. These Gram-negative bacteria, including the species Vibrio vulnificus, Vibrio parahaemolyticus and Vibrio cholerae, grow in warm, low-salinity waters, and their abundance in the natural environment mirrors ambient environmental temperatures. In a rapidly warming marine environment, there are greater numbers of human infections, and most notably outbreaks linked to extreme weather events such as heatwaves in temperate regions such as Northern Europe. Because the growth of pathogenic vibrios in the natural environment is largely dictated by temperature, we argue that this group of pathogens represents an important and tangible barometer of climate change in marine systems. We provide a number of specific examples of the impacts of climate change on this group of bacteria and their associated diseases, and discuss advanced strategies to improve our understanding of these emerging waterborne diseases through the integration of microbiological, genomic, epidemiological, climatic, and ocean sciences. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
Dale, Katie; Kirk, Martyn; Sinclair, Martha; Hall, Robert; Leder, Karin
2010-10-01
To examine the frequency and circumstances of reported waterborne outbreaks of gastroenteritis in Australia. Examination of data reported to OzFoodNet between 2001 and 2007. During these seven years, 6,515 gastroenteritis outbreaks were reported to OzFoodNet, most of which were classified as being transmitted person-to-person or from an unknown source. Fifty-four (0.83%) outbreaks were classified as either 'waterborne' or 'suspected waterborne', of which 78% (42/54) were attributed to recreational water and 19% (10/54) to drinking water. Of the drinking water outbreaks, implicated pathogens were found on all but one occasion and included Salmonella sp. (five outbreaks), Campylobacter jejuni (three outbreaks) and Giardia (one outbreak). There have been few waterborne outbreaks detected in Australia, and most of those reported have been associated with recreational exposure. However, there are difficulties in identifying and categorising gastroenteritis outbreaks, as well as in obtaining microbiological and epidemiological evidence, which can result in misclassification or underestimation of water-associated events. Gastroenteritis surveillance data show that, among reported water-associated gastroenteritis outbreaks in Australia, recreational exposure is currently more common than a drinking water source. However, ongoing surveillance for waterborne outbreaks is important, especially as drought conditions may necessitate replacement of conventional drinking water supplies with alternative water sources, which could incur potential for new health risks. © 2010 The Authors. Journal Compilation © 2010 Public Health Association of Australia.
Daniels, N A; Neimann, J; Karpati, A; Parashar, U D; Greene, K D; Wells, J G; Srivastava, A; Tauxe, R V; Mintz, E D; Quick, R
2000-04-01
Enterotoxigenic Escherichia coli (ETEC) has become the leading bacterial cause of gastroenteritis outbreaks on cruise ships. Investigation of recent outbreaks of ETEC gastroenteritis on 3 cruise ships indicated that all were associated with consuming beverages with ice cubes on board the ship (relative risk [RR], 1.4, 95% confidence interval [CI], 1.0-1.9, P=.02; RR, 1.9, 95% CI, 1.3-2. 9, P<.001; and RR, 1.3, 95% CI, 1.0-1.6, P<.01), and 2 were associated with drinking unbottled water (RR, 2.7, 95% CI, 1.8-4.1, P<.001; RR, 1.7, 95% CI, 1.3-2.3, P<.001). Multiple ETEC serotypes were detected in patients' stool specimens in each of the 3 outbreaks, and 12 (38%) of 32 isolates were resistant to > or =3 antimicrobial agents. ETEC appears to be emerging as a waterborne pathogen on cruise ships. Water bunkered in overseas ports was the likely source of ETEC infection in these outbreaks. To ensure passenger safety, cruise ships that take on water in foreign ports must ensure that water treatment and monitoring systems function properly.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-31
.... The proposed revisions require systems that have an indication of coliform contamination in the... deaths due to potential fecal contamination and waterborne pathogen exposure. This proposal also...
Elimination of viruses from domestic wastewater: requirements and technologies.
Zhang, Chong-Miao; Xu, Li-Mei; Xu, Peng-Cheng; Wang, Xiaochang C
2016-04-01
Domestic wastewater contains various pathogens, which, if not sufficiently eliminated, may enter the receiving water bodies and cause water-transmitted diseases. Among the waterborne pathogens, viruses may occur, survive and/or decay much differently from bacteria in water. In many cases, the diseases caused by viruses are more severe. Therefore, research efforts are mainly directed at the behavior of viruses in water environments, as well as the elimination of viruses from wastewater. In this paper, an overview of the occurrence of viruses in wastewater is presented, together with their categories, methods of detection and potential to cause waterborne diseases. As wastewater treatment plants are critical nodes for the influx and termination of virus transmission, the behavior of viruses at each stage of treatment is reviewed. Particular attention is paid to the unit operations, which play crucial roles in virus removals, such as coagulation and membrane filtration, and that for virus inactivation, such as chemical disinfection and UV irradiation. Future needs for the development of new technologies for virus elimination, source control, and finding more suitable indicators of viral pathogens are also highlighted.
ESTABLISH AND STANDARDIZE METHODOLOGY FOR ...
Research is conducted to develop and standardize methods to detect and measure occurrence of human enteric viruses that cause waterborne disease. The viruses of concern include the emerging pathogens--hepatitis E virus and group B rotaviruses. Also of concern are the coxsackieviruses and echoviruses--two members of the Office of Water's Contaminant Candidate List (CCL). Under this task, indicators of fecal pollution are also being evaluated as to their importance in evaluating microbial water quality. Another focus of the research is to address the standardization, evaluation and promulgation of detection methods for bacterial viruses. Develop sensitive techniques to detect and identify emerging human waterborne pathogenic viruses and viruses on the CCL.Determine effectiveness of viral indicators to measure microbial quality in water matrices.Support activities: (a) culture and distribution of mammalian cells for Agency and scientific community research needs, (b) provide operator expertise for research requiring confocal and electron microscopy, (c) glassware cleaning, sterilization and biological waste disposal for the Cincinnati EPA facility, (d) operation of infectious pathogenic suite, (e) maintenance of walk-in constant temperature rooms and (f) provide Giardia cysts.
River Networks As Ecological Corridors for Species, Populations and Pathogens of Water-Borne Disease
NASA Astrophysics Data System (ADS)
Rinaldo, A.
2014-12-01
River basins are a natural laboratory for the study of the integration of hydrological, ecological and geomorphological processes. Moving from morphological and functional analyses of dendritic geometries observed in Nature over a wide range of scales, this Lecture addresses essential ecological processes that take place along dendritic structures, hydrology-driven and controlled, like e.g.: population migrations and human settlements, that historically proceeded along river networks to follow water supply routes; riparian ecosystems composition that owing to their positioning along streams play crucial roles in their watersheds and in the loss of biodiversity proceeding at unprecedented rates; waterborne disease spreading, like epidemic cholera that exhibits epidemic patterns that mirror those of watercourses and of human mobility and resurgences upon heavy rainfall. Moreover, the regional incidence of Schistosomiasis, a parasitic waterborne disease, and water resources developments prove tightly related, and proliferative kidney disease in fish thrives differently in pristine and engineered watercourses: can we establish quantitatively the critical linkages with hydrologic drivers and controls? How does connectivity within a river network affect community composition or the spreading mechanisms? Does the river basin act as a template for biodiversity or for species' persistence? Are there hydrologic controls on epidemics of water-borne disease? Here, I shall focus on the noteworthy scientific perspectives provided by spatially explicit eco-hydrological studies centered on river networks viewed as ecological corridors for species, populations and pathogens of waterborne disease. A notable methodological coherence is granted by the mathematical description of river networks as the support for reactive transport. The Lecture overviews a number of topics idiosyncratically related to my own research work but ideally aimed at a coherent body of materials and methods. A theory is thus argued to emerge on the role of dendritic geometries as environmental support for ecological dynamics and processes - a fun and possibly even instructive novel research field, possibly a hotspot of eco-hydrologic research in the years to come.
Safe drinking water and waterborne outbreaks.
Moreira, N A; Bondelind, M
2017-02-01
The present work compiles a review on drinking waterborne outbreaks, with the perspective of production and distribution of microbiologically safe water, during 2000-2014. The outbreaks are categorised in raw water contamination, treatment deficiencies and distribution network failure. The main causes for contamination were: for groundwater, intrusion of animal faeces or wastewater due to heavy rain; in surface water, discharge of wastewater into the water source and increased turbidity and colour; at treatment plants, malfunctioning of the disinfection equipment; and for distribution systems, cross-connections, pipe breaks and wastewater intrusion into the network. Pathogens causing the largest number of affected consumers were Cryptosporidium, norovirus, Giardia, Campylobacter, and rotavirus. The largest number of different pathogens was found for the treatment works and the distribution network. The largest number of affected consumers with gastrointestinal illness was for contamination events from a surface water source, while the largest number of individual events occurred for the distribution network.
Jalava, Katri; Rintala, Hanna; Ollgren, Jukka; Maunula, Leena; Gomez-Alvarez, Vicente; Revez, Joana; Palander, Marja; Antikainen, Jenni; Kauppinen, Ari; Räsänen, Pia; Siponen, Sallamaari; Nyholm, Outi; Kyyhkynen, Aino; Hakkarainen, Sirpa; Merentie, Juhani; Pärnänen, Martti; Loginov, Raisa; Ryu, Hodon; Kuusi, Markku; Siitonen, Anja; Miettinen, Ilkka; Santo Domingo, Jorge W.; Hänninen, Marja-Liisa; Pitkänen, Tarja
2014-01-01
Failures in the drinking water distribution system cause gastrointestinal outbreaks with multiple pathogens. A water distribution pipe breakage caused a community-wide waterborne outbreak in Vuorela, Finland, July 2012. We investigated this outbreak with advanced epidemiological and microbiological methods. A total of 473/2931 inhabitants (16%) responded to a web-based questionnaire. Water and patient samples were subjected to analysis of multiple microbial targets, molecular typing and microbial community analysis. Spatial analysis on the water distribution network was done and we applied a spatial logistic regression model. The course of the illness was mild. Drinking untreated tap water from the defined outbreak area was significantly associated with illness (RR 5.6, 95% CI 1.9–16.4) increasing in a dose response manner. The closer a person lived to the water distribution breakage point, the higher the risk of becoming ill. Sapovirus, enterovirus, single Campylobacter jejuni and EHEC O157:H7 findings as well as virulence genes for EPEC, EAEC and EHEC pathogroups were detected by molecular or culture methods from the faecal samples of the patients. EPEC, EAEC and EHEC virulence genes and faecal indicator bacteria were also detected in water samples. Microbial community sequencing of contaminated tap water revealed abundance of Arcobacter species. The polyphasic approach improved the understanding of the source of the infections, and aided to define the extent and magnitude of this outbreak. PMID:25147923
2013-09-06
Despite advances in water management and sanitation, waterborne disease outbreaks continue to occur in the United States. CDC collects data on waterborne disease outbreaks submitted from all states and territories through the Waterborne Disease and Outbreak Surveillance System. During 2009-2010, the most recent years for which finalized data are available, 33 drinking water-associated outbreaks were reported, comprising 1,040 cases of illness, 85 hospitalizations, and nine deaths. Legionella accounted for 58% of outbreaks and 7% of illnesses, and Campylobacter accounted for 12% of outbreaks and 78% of illnesses. The most commonly identified outbreak deficiencies in drinking water-associated outbreaks were Legionella in plumbing systems (57.6%), untreated ground water (24.2%), and distribution system deficiencies (12.1%), suggesting that efforts to identify and correct these deficiencies could prevent many outbreaks and illnesses associated with drinking water. In addition to the drinking water outbreaks, 12 outbreaks associated with other nonrecreational water were reported, comprising 234 cases of illness, 51 hospitalizations, and six deaths. Legionella accounted for 58% of these outbreaks, 42% of illnesses, 96% of hospitalizations, and all deaths. Public health, regulatory, and industry professionals can use this information to target prevention efforts against pathogens, infrastructure problems, and water sources associated with waterborne disease outbreaks.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-21
... is necessary to protect the public from the hazards associated with airborne and waterborne... the hazards associated with the airborne and waterborne activities during the exercise. Discussion of... the Tampa Convention Center in Tampa, Florida. The exercise will consist of multiple airborne and...
Transport of selected bacterial pathogens in agricultural soil and quartz sand.
Schinner, Tim; Letzner, Adrian; Liedtke, Stefan; Castro, Felipe D; Eydelnant, Irwin A; Tufenkji, Nathalie
2010-02-01
The protection of groundwater supplies from microbial contamination necessitates a solid understanding of the key factors controlling the migration and retention of pathogenic organisms through the subsurface environment. The transport behavior of five waterborne pathogens was examined using laboratory-scale columns packed with clean quartz at two solution ionic strengths (10 mM and 30 mM). Escherichia coli O157:H7 and Yersinia enterocolitica were selected as representative Gram-negative pathogens, Enterococcus faecalis was selected as a representative Gram-positive organism, and two cyanobacteria (Microcystis aeruginosa and Anabaena flos-aquae) were also studied. The five organisms exhibit differing attachment efficiencies to the quartz sand. The surface (zeta) potential of the microorganisms was characterized over a broad range of pH values (2-8) at two ionic strengths (10 mM and 30 mM). These measurements are used to evaluate the observed attachment behavior within the context of the DLVO theory of colloidal stability. To better understand the possible link between bacterial transport in model quartz sand systems and natural soil matrices, additional experiments were conducted with two of the selected organisms using columns packed with loamy sand obtained from an agricultural field. This investigation highlights the need for further characterization of waterborne pathogen surface properties and transport behavior over a broader range of environmentally relevant conditions. Copyright 2008 Elsevier Ltd. All rights reserved.
MALDI-MIS INVESTIGATIONS OF DRINKING WATER PATHOGENS--GIARDIA AND CRYPTOSPORIDIUM
The protozoan parasites, Cryptosporidium parvum and Giardia lamblia, have been responsible for numerous waterborne outbreaks of gastrointestinal illness in the United States. The 1993 cryptosporidiosis outbreak in Milwaukee affected approximately 400,000 people and resulted in o...
AN IMPROVED METHOD FOR DETECTING VIRUSES IN WATER
Enteroviruses are important etiological agents of waterborne disease and are responsible for outbreaks of gastroenteritis. However, the prevalence and occurrence of these pathogens in raw drinking water sources is poorly understood. This is primarily due to the limited methods ...
VARIATIONS IN SEASONAL PATTERNS OF GASTROINTESTINAL INFECTIONS ALONG A RIVER
Epidemiologic analysis of waterborne diseases typically considers socio-economic, demographic, and pathogen-specific characteristics. However, hydrological parameters may need to be considered as well. Fate and transport models of watersheds have demonstrated impairment due to li...
Titanium Dioxide-Based Antibacterial Surfaces for Water Treatment
The field of water disinfection is gaining much interest since waterborne diseases caused by pathogenic microorganisms directly endanger human health. Antibacterial surfaces offer a new, ecofriendly technique to reduce the harmful disinfection byproducts that form in medical and ...
A Spike Cocktail Approach to Improve Microbial Performance Monitoring for Water Reuse
Water reuse, via either centralized treatment of traditional wastewater or decentralized treatment and on-site reuse, is becoming an increasingly important element of sustainable water management. Despite advances in waterborne pathogen detection methods, low and highly variable ...
FINGERPRINTING OF C. PARVUM BY MATRIX ASSISTED LASER DESORPTION IONIZATION MASS SPECTROMETRY
The oocysts of Cryptosporidium parvum, an enteric protozoan pathogen, are responsible for the worst microbial waterborne outbreak of gastroenteritis in recent history. The 1993 outbreak in Milwaukee, WI, sickened approximately 403,000 individuals, resulting in the hospitalizatio...
Saliva-based immunoassay of waterborne pathogen exposure
Water is our most important resource and ensuring its safety, security and sustainability is a global priority. Of almost equal importance is the protection of the global community from microbiological and chemical contaminants in our drinking and recreational water sources. Meth...
Edge, T A; Khan, I U H; Bouchard, R; Guo, J; Hill, S; Locas, A; Moore, L; Neumann, N; Nowak, E; Payment, P; Yang, R; Yerubandi, R; Watson, S
2013-10-01
The occurrence of waterborne pathogens was investigated at three drinking water intakes located about 2 km offshore in Lake Ontario. Water sampling was conducted over 3 years for Campylobacter spp., Cryptosporidium spp., Giardia spp., cultivable enteric viruses, and water quality parameters. All pathogens were detected in the offshore source water for each water treatment plant (WTP1 to WTP3), although at relatively low frequencies and concentrations. Giardia was the most common pathogen, occurring in 36% of water samples from the influent of WTP1 (n = 46), and with a maximum concentration of 0.70 cysts/liter in this influent. Cryptosporidium occurred as frequently as 15% in the WTP2 influent (n = 35), with a maximum concentration of 0.40 oocysts/liter in the WTP1 influent. The human Bacteroidales HF183 DNA marker was most common in the WTP1 influent (19%), and this was the only WTP where the Cryptosporidium hominis genotype was detected. No water quality parameter was predictive of pathogen occurrence across all three WTP influents. Escherichia coli was often below detection when pathogens were detected, and spikes in E. coli concentrations often did not coincide with pathogen occurrence. After summer rain events, river plumes had E. coli concentrations as high as 222 CFU/100 ml in surface waters 2 km offshore, without impacting drinking water intakes below the thermocline on the lake bottom. At times, prechlorination to control mussels at offshore intake cribs compromised the use of E. coli for "raw" water quality assessment, particularly for chlorine-resistant Cryptosporidium. E. coli measured by standard methods did not reliably predict pathogen occurrence at drinking water intakes in offshore ecosystems.
Khan, I. U. H.; Bouchard, R.; Guo, J.; Hill, S.; Locas, A.; Moore, L.; Neumann, N.; Nowak, E.; Payment, P.; Yang, R.; Yerubandi, R.; Watson, S.
2013-01-01
The occurrence of waterborne pathogens was investigated at three drinking water intakes located about 2 km offshore in Lake Ontario. Water sampling was conducted over 3 years for Campylobacter spp., Cryptosporidium spp., Giardia spp., cultivable enteric viruses, and water quality parameters. All pathogens were detected in the offshore source water for each water treatment plant (WTP1 to WTP3), although at relatively low frequencies and concentrations. Giardia was the most common pathogen, occurring in 36% of water samples from the influent of WTP1 (n = 46), and with a maximum concentration of 0.70 cysts/liter in this influent. Cryptosporidium occurred as frequently as 15% in the WTP2 influent (n = 35), with a maximum concentration of 0.40 oocysts/liter in the WTP1 influent. The human Bacteroidales HF183 DNA marker was most common in the WTP1 influent (19%), and this was the only WTP where the Cryptosporidium hominis genotype was detected. No water quality parameter was predictive of pathogen occurrence across all three WTP influents. Escherichia coli was often below detection when pathogens were detected, and spikes in E. coli concentrations often did not coincide with pathogen occurrence. After summer rain events, river plumes had E. coli concentrations as high as 222 CFU/100 ml in surface waters 2 km offshore, without impacting drinking water intakes below the thermocline on the lake bottom. At times, prechlorination to control mussels at offshore intake cribs compromised the use of E. coli for “raw” water quality assessment, particularly for chlorine-resistant Cryptosporidium. E. coli measured by standard methods did not reliably predict pathogen occurrence at drinking water intakes in offshore ecosystems. PMID:23835181
Obtaining Highly Purified Toxoplasma gondii Oocysts by a Discontinuous Cesium Chloride Gradient
Toxoplasma gondii is an obligate intracellular protozoan pathogen that commonly infects humans. It is a well characterized apicomplexan associated with causing food- and water-borne disease outbreaks. The definitive host is the feline species where sexual replication occurs res...
Murphy, H M; Thomas, M K; Schmidt, P J; Medeiros, D T; McFADYEN, S; Pintar, K D M
2016-05-01
Waterborne illness related to the consumption of contaminated or inadequately treated water is a global public health concern. Although the magnitude of drinking water-related illnesses in developed countries is lower than that observed in developing regions of the world, drinking water is still responsible for a proportion of all cases of acute gastrointestinal illness (AGI) in Canada. The estimated burden of endemic AGI in Canada is 20·5 million cases annually - this estimate accounts for under-reporting and under-diagnosis. About 4 million of these cases are domestically acquired and foodborne, yet the proportion of waterborne cases is unknown. There is evidence that individuals served by private systems and small community systems may be more at risk of waterborne illness than those served by municipal drinking water systems in Canada. However, little is known regarding the contribution of these systems to the overall drinking water-related AGI burden in Canada. Private water supplies serve an estimated 12% of the Canadian population, or ~4·1 million people. An estimated 1·4 million (4·1%) people in Canada are served by small groundwater (2·6%) and surface water (1·5%) supplies. The objective of this research is to estimate the number of AGI cases attributable to water consumption from these supplies in Canada using a quantitative microbial risk assessment (QMRA) approach. This provides a framework for others to develop burden of waterborne illness estimates for small water supplies. A multi-pathogen QMRA of Giardia, Cryptosporidium, Campylobacter, E. coli O157 and norovirus, chosen as index waterborne pathogens, for various source water and treatment combinations was performed. It is estimated that 103 230 AGI cases per year are due to the presence of these five pathogens in drinking water from private and small community water systems in Canada. In addition to providing a mechanism to assess the potential burden of AGI attributed to small systems and private well water in Canada, this research supports the use of QMRA as an effective source attribution tool when there is a lack of randomized controlled trial data to evaluate the public health risk of an exposure source. QMRA is also a powerful tool for identifying existing knowledge gaps on the national scale to inform future surveillance and research efforts.
Chaidez, Cristóbal; Ibarra-Rodríguez, Juan R; Valdez-Torres, José Benigno; Soto, Marcela; Gerba, Charles P; Castro-Del Campo, Nohelia
2016-09-01
In developing countries, rural communities often face the lack of potable water infrastructure and must rely on untreated sources for drinking, which are often contaminated with waterborne pathogens. The use of home water treatment devices is seen as one means of reducing the risk of exposure to waterborne pathogens. The aim of this study was to evaluate the microbiological and physicochemical performance of a simple in-home point-of-use device based on gravity ultrafiltration through an ultrafilter membrane. Twenty-five randomly selected households from 2 rural communities in Culiacán, Mexico, were enrolled. Water samples were collected before and after treatment and during storage for a period of 8 weeks. Heterotrophic bacteria, total coliforms, fecal coliforms, Escherichia coli, and Giardia spp were quantified, as well as various physicochemical parameters. All of the untreated water samples contained high levels of indicator bacteria, but none were detected in the treated water fulfilling the requirements set by the Mexican Norm (NOM-127-SSA1-1994) and the World Health Organization guidelines for drinking water. However, indicator bacteria (fecal coliforms and E coli) were detected in every sample from water stored 24 hours after treatment. This study demonstrated that point-of-use filters using gravity-fed ultrafilters are a low-cost, effective water treatment technology for water of poor microbial quality. However, further identification of the sources and mechanisms by which water is contaminated when stored after treatment will help with designing and implementing better strategies for keeping water safe for domestic use. Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.
Molecular assessment of bacterial pathogens - a contribution to drinking water safety.
Brettar, Ingrid; Höfle, Manfred G
2008-06-01
Human bacterial pathogens are considered as an increasing threat to drinking water supplies worldwide because of the growing demand of high-quality drinking water and the decreasing quality and quantity of available raw water. Moreover, a negative impact of climate change on freshwater resources is expected. Recent advances in molecular detection technologies for bacterial pathogens in drinking water bear the promise in improving the safety of drinking water supplies by precise detection and identification of the pathogens. More importantly, the array of molecular approaches allows understanding details of infection routes of waterborne diseases, the effects of changes in drinking water treatment, and management of freshwater resources.
Rainbow trout fry were exposed to arsenic in water only, diet only, or both diet and water in 28-d studies evaluating survival and growth. Diets consisted of Lumbriculus variegatus that were exposed to multiple concentrations of waterborne arsenate for 7d and then fed to test fi...
Assavasilavasukul, Prapakorn; Lau, Boris L T; Harrington, Gregory W; Hoffman, Rebecca M; Borchardt, Mark A
2008-05-01
The presence of waterborne enteric pathogens in municipal water supplies contributes risk to public health. To evaluate the removal of these pathogens in drinking water treatment processes, previous researchers have spiked raw waters with up to 10(6) pathogens/L in order to reliably detect the pathogens in treated water. These spike doses are 6-8 orders of magnitude higher than pathogen concentrations routinely observed in practice. In the present study, experiments were conducted with different sampling methods (i.e., grab versus continuous sampling) and initial pathogen concentrations ranging from 10(1) to 10(6) pathogens/L. Results showed that Cryptosporidium oocyst and Giardia cyst removal across conventional treatment were dependent on initial pathogen concentrations, with lower pathogen removals observed when lower initial pathogen spike doses were used. In addition, higher raw water turbidity appeared to result in higher log removal for both Cryptosporidium oocysts and Giardia cysts.
TOXOPLASMA GONDII : UPTAKE AND SURVIVAL OF OOCYSTS IN FREE-LIVING AMOEBAE
USDA-ARS?s Scientific Manuscript database
Waterborne transmission of the oocyst stage of Toxoplasma gondii can cause outbreaks of clinical toxoplasmosis in humans and infection of marine mammals. In water-related environments and soil, free-living amoebae are considered potential carriers of various pathogens, but knowledge on interactions ...
Chemistry, Toxicity and Health Risk Assessment of Drinking Water Disinfection ByProducts
Disinfection byproducts (DBPs) are formed by the reaction of oxidizing chemicals (such as chlorine, ozone and chloramines) used to control waterborne pathogens with natural organic material and other substances in water. DBP mixture composition varies as a function of geographic ...
Modeling Human Exposure Risk to Nontuberculous Mycobacteria in Central North Carolina
Nontuberculous mycobacteria (NTM) are a broad group of soil-and water-borne bacteria. Some species are pathogenic and may cause serious infections in the lungs, soft tissues, bones and skin. Infections in humans are associated with environmental exposures to contaminated soil, ae...
Chapter 2. Assessing the importance of zoonotic waterborne pathogens
USDA-ARS?s Scientific Manuscript database
Cryptosporidium, an apicomplexan protozoan, is reported to infect persons in 106 countries and more than 150 species of other mammals worldwide. Estimates of prevalence in humans vary greatly because reporting is not universally required, diagnostic methods vary greatly, and many persons have no acc...
USING SAND AND MORINGA OLEIFERA PROTEIN FOR A SUSTAINABLE WATER FILTER
This design will have a significant impact on people throughout developing equatorial regions by reducing their exposure to water borne pathogens. Reducing water-borne illnesses will improve people’s health to allow them to build prosperity within their communities. T...
A VISION FOR A BEACH FORECASTING TOOL
The societal value of safe access to swimmable water is intuitive and in many countries it is a legal right. Threats to water quality reduce these recreational opportunities. The risk comes from exposure to waterborne pathogens from a myriad of sources, both human and animal. ...
The United States Environmental Protection Agency (USEPA) is interested in assessing health risks associated with emerging or potential waterborne pathogens. To this end, the Agency has established a Candidate Contaminant List (CCL) that includes Aeromonas hydrophila an...
Risk of waterborne illness via drinking water in the United States.
Reynolds, Kelly A; Mena, Kristina D; Gerba, Charles P
2008-01-01
Outbreaks of disease attributable to drinking water are not common in the U.S., but they do still occur and can lead to serious acute, chronic, or sometimes fatal health consequences, particularly in sensitive and immunocompromised populations. From 1971 to 2002, there were 764 documented waterborne outbreaks associated with drinking water, resulting in 575,457 cases of illness and 79 deaths (Blackburn et al. 2004; Calderon 2004); however, the true impact of disease is estimated to be much higher. If properly applied, current protocols in municipal water treatment are effective at eliminating pathogens from water. However, inadequate, interrupted, or intermittent treatment has repeatedly been associated with waterborne disease outbreaks. Contamination is not evenly distributed but rather affected by the number of pathogens in the source water, the age of the distribution system, the quality of the delivered water, and climatic events that can tax treatment plant operations. Private water supplies are not regulated by the USEPA and are generally not treated or monitored, although very few of the municipal systems involved in documented outbreaks exceeded the USEPA's total coliform standard in the preceding 12 mon (Craun et al. 2002). We provide here estimates of waterborne infection and illness risks in the U.S. based on the total number of water systems, source water type, and total populations exposed. Furthermore, we evaluated all possible illnesses associated with the microbial infection and not just gastroenteritis. Our results indicate that 10.7 M infections/yr and 5.4 M illnesses/yr occur in populations served by community groundwater systems; 2.2 M infections/yr and 1.1 M illnesses/yr occur in noncommunity groundwater systems; and 26.0 M infections/yr and 13.0 M illnesses/yr occur in municipal surface water systems. The total estimated number of waterborne illnesses/yr in the U.S. is therefore estimated to be 19.5 M/yr. Others have recently estimated waterborne illness rates of 12M cases/yr (Colford et al. 2006) and 16 M cases/yr (Messner et al. 2006), yet our estimate considers all health outcomes associated with exposure to pathogens in drinking water rather than only gastrointestinal illness. Drinking water outbreaks exemplify known breaches in municipal water treatment and distribution processes and the failure of regulatory requirements to ensure water that is free of human pathogens. Water purification technologies applied at the point-of-use (POU) can be effective for limiting the effects of source water contamination, treatment plant inadequacies, minor intrusions in the distribution system, or deliberate posttreatment acts (i.e., bioterrorism). Epidemiological studies are conflicting on the benefits of POU water treatment. One prospective intervention study found that consumers of reverse-osmosis (POU) filtered water had 20%-35% less gastrointestinal illnesses than those consuming regular tap water, with an excess of 14% of illness due to contaminants introduced in the distribution system (Payment 1991, 1997). Two other studies using randomized, blinded, controlled trials determined that the risks were equal among groups supplied with POU-treated water compared to untreated tap water (Hellard et al. 2001; Colford et al. 2003). For immunocompromised populations, POU water treatment devices are recommended by the CDC and USEPA as one treatment option for reducing risks of Cryptosporidium and other types of infectious agents transmitted by drinking water. Other populations, including those experiencing "normal" life stages such as pregnancy, or those very young or very old, might also benefit from the utilization of additional water treatment options beyond the current multibarrier approach of municipal water treatment.
Ma, Jiawen; Hu, Yue; Villegas, Eric N.; Xiao, Lihua
2018-01-01
Cryptosporidiosis, giardiasis, and microsporidiosis are important waterborne diseases. In the standard for wastewater treatment plant (WWTP) effluents in China and other countries, the fecal coliform count is the only microbial indicator, raising concerns about the potential for pathogen transmission through WWTP effluent reuse. In this study, we collected 50 effluent samples (30 L/sample) from three municipal WWTPs in Shanghai, China, and analyzed for Cryptosporidium spp., Giardia duodenalis and Enterocytozoon bieneusi by microscopy and/or polymerase chain reaction (PCR). Moreover, propidium monoazide (PMA)-PCR was used to assess the viability of oocysts/cysts. The microscopy and PCR-positive rates for Cryptosporidium spp. were 62% and 40%, respectively. The occurrence rates of G. duodenalis were 96% by microscopy and 92–100% by PCR analysis of three genetic loci. Furthermore, E. bieneusi was detected in 70% (35/50) of samples by PCR. Altogether, 10 Cryptosporidium species or genotypes, two G. duodenalis genotypes, and 11 E. bieneusi genotypes were found, most of which were human-pathogenic. The chlorine dioxide disinfection employed in WWTP1 and WWTP3 failed to inactivate the residual pathogens; 93% of the samples from WWTP1 and 83% from WWTP3 did not meet the national standard on fecal coliform levels. Thus, urban WWTP effluents often contain residual waterborne human pathogens. PMID:27280607
Schijven, Jack; Bouwknegt, Martijn; de Roda Husman, Ana Maria; Rutjes, Saskia; Sudre, Bertrand; Suk, Jonathan E; Semenza, Jan C
2013-12-01
Climate change may impact waterborne and foodborne infectious disease, but to what extent is uncertain. Estimating climate-change-associated relative infection risks from exposure to viruses, bacteria, or parasites in water or food is critical for guiding adaptation measures. We present a computational tool for strategic decision making that describes the behavior of pathogens using location-specific input data under current and projected climate conditions. Pathogen-pathway combinations are available for exposure to norovirus, Campylobacter, Cryptosporidium, and noncholera Vibrio species via drinking water, bathing water, oysters, or chicken fillets. Infection risk outcomes generated by the tool under current climate conditions correspond with those published in the literature. The tool demonstrates that increasing temperatures lead to increasing risks for infection with Campylobacter from consuming raw/undercooked chicken fillet and for Vibrio from water exposure. Increasing frequencies of drought generally lead to an elevated infection risk of exposure to persistent pathogens such as norovirus and Cryptosporidium, but decreasing risk of exposure to rapidly inactivating pathogens, like Campylobacter. The opposite is the case with increasing annual precipitation; an upsurge of heavy rainfall events leads to more peaks in infection risks in all cases. The interdisciplinary tool presented here can be used to guide climate change adaptation strategies focused on infectious diseases. © 2013 Society for Risk Analysis.
The Role of Biofilms in Drinking Water Exposure to Potentially Pathogenic Legionella spp.
Legionellosis is a bacterial infection caused by species of the genera Legionella and is the most common waterborne disease reported in the United States. This type of infection has two clinically distinct forms: Legionnaire's disease, a severe type of infection, which include...
USDA-ARS?s Scientific Manuscript database
Drinking water contaminated with microbial pathogens can cause outbreaks of infectious disease, and these outbreaks are traditionally studied using epidemiologic methods. Quantitative microbial risk assessment (QMRA) can predict – and therefore help prevent – such outbreaks, but it has never been r...
Cryptosporidiosis, giardiasis, and microsporidiosis are important waterborne diseases. In the standard for wastewater treatment plant (WWTP) effluents in China and other countries, fecal coliform is the only microbial indicator, raising concerns about the potential for pathogen t...
Chemical disinfection of drinking water is considered one of the major public health triumphs of the 20th century, as it reduces concentrations of potentially pathogenic microorganisms resulting in corresponding decreases in morbidity and mortality from water-borne diseases. An ...
U.S. EPA’s Four Lab Study: Integrated Assessment of Complex Disinfection Byproduct Mixtures - Slides
Chemical disinfection of drinking water is considered one of the major public health triumphs of the 20th century, as it reduces concentrations of potentially pathogenic microorganisms resulting in corresponding decreases in morbidity and mortality from water-borne diseases. An ...
The Effect of pH on Stability and Sorption of Cryptosporidium parvum Oocysts by Nanoparticles
Cryptosporidium parvum (C. parvum) are waterborne pathogens, which are released into the environment through infected human or animal feces. Their ability to survive outside their host organisms in harsh environmental conditions presents one of the most challenging tasks in resea...
Finsel, Ivo; Hilbi, Hubert
2015-07-01
Legionella species are ubiquitous, waterborne bacteria that thrive in numerous ecological niches. Yet, in contrast to many other environmental bacteria, Legionella spp. are also able to grow intracellularly in predatory protozoa. This feature mainly accounts for the pathogenicity of Legionella pneumophila, which causes the majority of clinical cases of a severe pneumonia termed Legionnaires' disease. The pathomechanism underlying L. pneumophila infection is based on macrophage resistance, which in turn is largely defined by the opportunistic pathogen's resistance towards amoebae. L. pneumophila replicates in macrophages or amoebae in a unique membrane-bound compartment, the Legionella-containing vacuole (LCV). LCV formation requires the bacterial intracellular multiplication/defective for organelle trafficking (Icm/Dot) type IV secretion system and involves a plethora of translocated effector proteins, which subvert pivotal processes in the host cell. Of the ca. 300 different experimentally validated Icm/Dot substrates, about 50 have been studied and attributed a cellular function to date. The versatility and ingenuity of these effectors' mode of actions is striking. In this review, we summarize insight into the cellular functions and biochemical activities of well-characterized L. pneumophila effector proteins and the host pathways they target. Recent studies not only substantially increased our knowledge about pathogen-host interactions, but also shed light on novel biological mechanisms. © 2015 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Packman, A. I.; Lau, B. L.; Harter, T.; Atwill, E. R.
2007-12-01
Waterborne diseases are transmitted through numerous environmental pathways, and their migration is strongly mediated by interaction with a wide variety of sediments and other natural materials during transport. Here we provide an overview of factors that affect the fate of persistent water-borne pathogens, focusing particularly on the zoonotic pathogen Cryptosporidium parvum as an example. While individual microbial cells are both small and have low specific gravity, suggesting that they should be highly mobile and remain suspended for long periods of time, attachment to a variety of background materials can substantially reduce pathogen mobility. Cryptosporidium oocysts readily associate with both inorganic and organic particles, resulting in the formation of aggregates. This process tends to increase the effective settling velocity of C. parvum in surface waters. Similarly, pathogens readily become associated with the solid matrix during transport in groundwater, resulting in removal by filtration. However, this process is reversible with C. parvum, resulting in a slow long-term release following the initial deposition. Pathogens also become associated with biofilms, which are surface-attached communities of microorganisms in a gelatinous matrix. The presence of biofilms increases the immobilization and retention of Cryptosporidium on solid surfaces. All of these processes influence pathogen transmission in surface waters such as rivers and water-supply canals. In these environments, pathogens can be immobilized by deposition into stable sediment beds by a combination of gravitational sedimentation and advection into pore waters followed by subsurface filtration. Association with background suspended matter tends to increase pathogen deposition by sedimentation, and the presence of benthic (sedimentary) biofilms also tends to increase pathogen retention. For pathogens that remain viable for long periods of time in natural aquatic systems, as is the case with Cryptosporidium and other cyst-and spore-forming organisms, then the sediments and sedimentary biofilms become an environmental reservoir of pathogens. Cysts retained in biofilms appear to be relatively difficult to resuspend, but slow, long-term biological release and high-flow events that mobilize streambed sediments both deliver pathogens into transport.
Disinfection of Common Waterborne Pathogens
ERIC Educational Resources Information Center
Swim, Edward W.
2010-01-01
As part of an integrative learning experience at the end of a sophomore Calculus II course at the United States Military Academy, this project served as a multidisciplinary problem-solving exercise that explored the connections among mathematics, biology, and other fields of study. During a seven-lesson block of instruction, this module was…
EMERGING PATHOGENS OF ANIMAL ORIGIN: UNIQUE CHALLENGES FOR QUANTITATIVE MICROBIAL RISK ASSESSMENT
Recently severe human epidemics caused by waterborne Cryptosporidium parvum and Escherichia coli Strain (157:H7 of animal origin have attracted much attention in the national news media. Among the 130 diseases that can be transmitted to man from domestic and wild animals, a signi...
No degree of treatment will insure the delivery of a safe water supplyto the consumer's tap when the distribution system is subject to cross-connections water pressure losses, frequent line breaks, open reservoirs and infrastructure deterioration. n one recent U.S. outbreak, wate...
TRANSPORT AND SURVIVAL OF VIRUSES IN THE SUBSURFACE PROCESSES, EXPERIMENTS, AND SIMULATION MODELS
The remediation of ground water contaminated with waterborne pathogens, in particular with viruses, is based on their probable or actual ability to be transported from the source of origin to a point of withdrawal while maintaining the capacity to cause infections. The transport ...
Ultra-sensitive detection using integrated waveguide technologies
USDA-ARS?s Scientific Manuscript database
There is a pressing need to detect analytes at very low concentrations, such as food- and water-borne pathogens (e.g. E. coli O157:H7) and biothreat agents (e.g., anthrax, toxins). Common fluorescence detection methods, such as 96 well plate readers, are not sufficiently sensitive for low concentra...
Climate change in the North American Arctic: A one health perspective
USDA-ARS?s Scientific Manuscript database
Climate change is expected to increase the prevalence of acute and chronic diseases among human and animal populations within the Arctic and sub-Arctic latitudes of North America. Warmer temperatures are expected to increase disease risks from food-borne pathogens, water-borne diseases, and vector-...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-20
... contents of the docket, and access those documents in the public docket that are available electronically... monitor recreational water quality; assess, manage, and communicate health risks from waterborne microbial... public exposure to microbial pathogens. To qualify for a BEACH Act Grant, a state must submit information...
Computational toxicology is a rapid approach to screening for toxic effects and looking for common outcomes that can result in predictive models. The long term project will result in the development of a database of mRNA responses to known water-borne pathogens. An understanding...
Escherichia coli O157 H:7 has been linked to waterborne outbreaks in the United States and abroad. Methods employed to detect this pathogen typically are cultural based and take advantage of phenotypic traits that are specific for this serotype. These phenotypic characteristics...
Escherichia coli O157:H7 has been linked to waterborne outbreaks in the United States and abroad. Methods employed to detect this pathogen typically are cultural based and take advantage of phenotypic traits that are specific for this serotype, including slow sorbitol fermentati...
DEVELOPMENT OF A MOLECULAR METHOD TO IDENTIFY HEPATITIS E VIRUS
Hepatitis E virus (HEV) is a waterborne emerging pathogen that causes significant illness in the developing world. Thus far, an HEV outbreak has not been reported in the U.S., although a swine variant of the virus is common in Midwestern hogs. Because viruses isolated from two ...
THE USE OF RT-PCR FOR THE DETECTION OF ENTERIC VIRUSES IN PRAIRIE SURFACE DRINKING WATER SUPPLIES
Concerns over the microbial safety of drinking water supplies have focused on bacteria and parasites while the occurrence of pathogenic waterborne viruses have been largely ignored. In fact, water supplies are not routinely monitored for human enteric viruses. This is despite t...
Impact of climate change on waterborne diseases.
Funari, Enzo; Manganelli, Maura; Sinisi, Luciana
2012-01-01
Change in climate and water cycle will challenge water availability but it will also increase the exposure to unsafe water. Floods, droughts, heavy storms, changes in rain pattern, increase of temperature and sea level, they all show an increasing trend worldwide and will affect biological, physical and chemical components of water through different paths thus enhancing the risk of waterborne diseases. This paper is intended, through reviewing the available literature, to highlight environmental changes and critical situations caused by floods, drought and warmer temperature that will lead to an increase of exposure to water related pathogens, chemical hazards and cyanotoxins. The final aim is provide knowledge-based elements for more focused adaptation measures.
On the intrinsic dynamics of bacteria in waterborne infections.
Yang, Chayu; Wang, Jin
2018-02-01
The intrinsic dynamics of bacteria often play an important role in the transmission and spread of waterborne infectious diseases. In this paper, we construct mathematical models for waterborne infections and analyze two types of nontrivial bacterial dynamics: logistic growth, and growth with Allee effects. For the model with logistic growth, we find that regular threshold dynamics take place, and the basic reproduction number can be used to characterize disease extinction and persistence. In contrast, the model with Allee effects exhibits much more complex dynamics, including the existence of multiple endemic equilibria and the presence of backward bifurcation and forward hysteresis. Copyright © 2017 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Kaushik, Rajni; Balasubramanian, Rajasekhar
2012-01-01
Bacterial pathogens in airborne particulate matter (PM) and in rainwater (RW) were detected using a robust and sensitive Real-Time PCR method. Both RW and PM were collected simultaneously in the tropical atmosphere of Singapore, which were then subjected to analysis for the presence of selected bacterial pathogens and potential pathogen of health concern ( Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Aeromonas hydrophila). These pathogens were found to be prevalent in both PM and RW samples with E. coli being the most prevalent potential pathogen in both types of samples. The temporal distribution of these pathogens in PM and RW was found to be similar to each other. Using the proposed microbiological technique, the atmospheric deposition (dry and wet deposition) of bacterial pathogens to lakes and reservoirs can be studied in view of growing concerns about the outbreak of waterborne diseases.
Gong, Xiangli; Li, Juntao; Zhang, Ying; Hou, Shuiping; Qu, Pinghua; Yang, Zhicong; Chen, Shouyi
2017-08-01
Legionella spp. are important waterborne pathogens. Molecular typing has become an important method for outbreaks investigations and source tracking of Legionnaires. In a survey program conducted by the Guangzhou Center for Disease Control and Prevention, multiple serotypes Legionella pneumophila (L. pneumophila) were isolated from waters in air-conditioning cooling towers in urban Guangzhou region, China between 2008 and 2011. Three genotyping methods, mip (macrophage infectivity potentiator) genotyping, SBT (sequence-based typing), and FAFLP (fluorescent amplified fragment length polymorphism analysis) were used to type these waterborne L. pneumophila isolates. The three methods were capable of typing all the 134 isolates and a reference strain of L. pneumophila (ATCC33153), with discriminatory indices of 0.7034, 0.9218, and 0.9376, for the mip, SBT, and FAFLP methods respectively. Among the 9 serotypes of the 134 isolates, 10, 50, and 34 molecular types were detected by the mip, SBT, and FAFLP methods respectively. The mip genotyping and SBT typing are more feasible for inter-laboratory results sharing and comparison of different types of L. pneumophila. The SBT and FAFLP typing methods were rapid with higher discriminatory abilities. Combinations of two or more of the typing methods enables more accurate typing of Legionella isolates for outbreak investigations and source tracking of Legionnaires. Copyright © 2017 Elsevier B.V. All rights reserved.
Haramoto, Eiji; Yamada, Kaoru; Nishida, Kei
2011-12-01
Limited information is available on the prevalence of waterborne pathogens in aquatic environments in developing countries. In this study, water samples were collected from nine shallow wells and a river in the Kathmandu Valley, Nepal, during the rainy season in 2009 and were subjected to detection of waterborne protozoa, viruses and coliphages using a recently developed method for simultaneous concentration of protozoa and viruses in water. Escherichia coli and total coliforms were also tested as indicator bacteria. At least one type of the five pathogens tested (Cryptosporidium, Giardia, human adenoviruses, and noroviruses of genogroups I and II) was detected in five groundwater samples (56%) (1000 ml each) from shallow wells. Compared with groundwater samples, the pathogens were more abundant in the river water sample (100ml); the concentrations of Cryptosporidium and Giardia were 140 oocysts/l and 8500 cysts/l, respectively, and the mean threshold cycle (Ct) values in real-time RT-PCR were 34.3, 36.8 and 34.0 for human adenoviruses and noroviruses of genogroups I and II, respectively. Genotyping of F-RNA coliphages by real-time RT-PCR was successfully used to differentiate human and animal faecal contamination in the samples. Moreover, for the groundwater samples, protozoa and viruses were detected only in E. coli-positive samples, suggesting that E. coli may be an appropriate indicator of pathogen contamination of valley groundwater. Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.
A HISTORICAL PERSPECTIVE OF DETECTION METHODS FOR GIARDIA CYSTS AND CRYPTOSPORIDIUM OOCYSTS IN WATER
In the mid-20th century Giardia was classified as a non-pathogenic commensal organism and Cryptosporidium was not recognized yet. However as early as 1946 a waterborne outbreak of giardiasis was suspected. From 1965 to 1979 it became clear that Giardia lamblia was indeed a human ...
Marla C. Downing; Thomas Jung; Vernon Thomas; Markus Blaschke; Michael F. Tuffly; Robin Reich
2010-01-01
Phytophthora alni subspecies alni Brasier and S.A. Kirk is a recently hybridized soil and waterborne pathogen causing root and collar rot of species of the genus Alnus spp. (alder). It has quickly spread throughout Europe via planting of infested nursery stock and irrigating fields with infested river...
Saliva has an important advantage over serum as a medium for antibody detection due to non-invasive sampling, which is critical for community-based epidemiological surveys. The development of a Luminex multiplex immunoassay for measurement of salivary IgG and IgA responses to pot...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-23
... index listing of the contents of the docket, and to access those documents in the docket that are... recreational water quality; assess, manage, and communicate health risks from waterborne microbial... public exposure to microbial pathogens. To qualify for a BEACH Act Grant, a state must submit information...
Some sub-populations, such as infants and children or those with weakened immune systems, are known to be particularly sensitive to the effects of certain waterborne pathogens and chemicals. The 1996 Amendments to the Safe Drinking Water Act (SDWA) require EPA to conduct research...
Microbial indicators, pathogens and methods for their monitoring in water environment.
Saxena, Gaurav; Bharagava, Ram Naresh; Kaithwas, Gaurav; Raj, Abhay
2015-06-01
Water is critical for life, but many people do not have access to clean and safe drinking water and die because of waterborne diseases. The analysis of drinking water for the presence of indicator microorganisms is key to determining microbiological quality and public health safety. However, drinking water-related illness outbreaks are still occurring worldwide. Moreover, different indicator microorganisms are being used in different countries as a tool for the microbiological examination of drinking water. Therefore, it becomes very important to understand the potentials and limitations of indicator microorganisms before implementing the guidelines and regulations designed by various regulatory agencies. This review provides updated information on traditional and alternative indicator microorganisms with merits and demerits in view of their role in managing the waterborne health risks as well as conventional and molecular methods proposed for monitoring of indicator and pathogenic microorganisms in the water environment. Further, the World Health Organization (WHO) water safety plan is emphasized in order to develop the better approaches designed to meet the requirements of safe drinking water supply for all mankind, which is one of the major challenges of the 21st century.
DEVELOPMENT OF MOLECULAR METHODS TO DETECT ...
A large number of human enteric viruses are known to cause gastrointestinal illness and waterborne outbreaks. Many of these are emerging viruses that do not grow or grow poorly in cell culture and so molecular detectoin methods based on the polymerase chain reaction (PCR) are being developed. Current studies focus on detecting two virus groups, the caliciviruses and the hepatitis E virus strains, both of which have been found to cause significant outbraks via contaminated drinking water. Once developed, these methods will be used to collect occurrence data for risk assessment studies. Develop sensitive techniques to detect and identify emerging human waterborne pathogenic viruses and viruses on the CCL.Determine effectiveness of viral indicators to measure microbial quality in water matrices.Support activities: (a) culture and distribution of mammalian cells for Agency and scientific community research needs, (b) provide operator expertise for research requiring confocal and electron microscopy, (c) glassware cleaning, sterilization and biological waste disposal for the Cincinnati EPA facility, (d) operation of infectious pathogenic suite, (e) maintenance of walk-in constant temperature rooms and (f) provide Giardia cysts.
Inactivation of a model coliphage virus in water by iodine
NASA Technical Reports Server (NTRS)
Brion, Gail M.; Silverstein, Joann
1992-01-01
Until now, NASA's space water reuse research program has not considered the transport of water-borne infectious enteric viruses; however, viral diseases probably are a signifficant concern in long-duration space missions. To simplify monitoring and prediction of pathogen distribution, model indicator strains historically have been used. In this research, the male specific RNA coliphage MS-2 is used as a model of enteric viruses due to their similar size and biochemical composition. Inactivation of some water-borne enteric viruses by iodine has previously been characterized. In this paper, iodine inactivation of the model coliphage MS-2 in buffered water is compared with earlier bench-scale disinfection survival data and with survival in iodinated simulated shower water used in a test water recycling system.
Detection, diversity, and population dynamics of waterborne Phytophthora ramorum populations
Catherine Eyre; Matteo Garbelotto
2015-01-01
Sudden oak death, the tree disease caused by Phytophthora ramorum, has significant environmental and economic impacts on natural forests on the U.S. west coast, plantations in the United Kingdom, and in the worldwide nursery trade. Stream baiting is vital for monitoring and early detection of the pathogen in high-risk areas and is performed...
: EPA Region 6, in collaboration with the Office of Research and Development and Office of Water (OW) in Cincinnati, Ohio, and the Louisiana Department of Health and Hospitals (LDHH), proposes a drinking water research project to understand how maintaining various drinking water...
USDA-ARS?s Scientific Manuscript database
Shiga toxin-producing Escherichia coli is a foodborne and waterborne pathogen and is responsible for outbreaks of human gastroenteritis. This report documents the draft genome sequences of seven O113:H21 strains recovered from livestock, wildlife, and soil samples collected in a major agricultural r...
MALDI-MS has long been established as a tool by which microorganisms can be characterized and identified. The U.S. Environmental Protection Agency (EPA) is investigating the potential of using this technique as a way to rapidly identify Aeromonas species in drinking water. A nu...
Studies on Disinfection By-Products and Drinking Water
Rostad, Colleen E.
2007-01-01
Drinking water is disinfected with chemicals to remove pathogens, such as Giardia and Cryptosproridium, and prevent waterborne diseases such as cholera and typhoid. During disinfection, by-products are formed at trace concentrations. Because some of these by-products are suspected carcinogens, drinking water utilities must maintain the effectiveness of the disinfection process while minimizing the formation of by-products.
ERIC Educational Resources Information Center
Altherr, Anne-Marie; Mosler, Hans-Joachim; Tobias, Robert; Butera, Fabrizio
2008-01-01
Solar water disinfection (SODIS) is an uncomplicated and cheap technology providing individuals with safe drinking water by exposing water-filled plastic bottles to sunlight for 6 hours to kill waterborne pathogens. Two communities were visited, and 81 families (40 SODIS users and 41 nonusers) were interviewed. The relationship between several…
USDA-ARS?s Scientific Manuscript database
Human norovirus (NoV) is the leading cause of non-bacterial acute gastroenteritis epidemics worldwide. High pressure processing (HPP) has been considered a promising non-thermal processing technology to inactivate food- and water-borne viral pathogens. Due to the lack of an effective cell culture fo...
Complete Genome Sequence of Plesiomonas shigelloides Type Strain NCTC10360
Fazal, Mohammed-Abbas; Burnett, Edward; Deheer-Graham, Ana; Oliver, Karen; Holroyd, Nancy; Russell, Julie E.
2016-01-01
Plesiomonas shigelloides is a Gram-negative rod within the Enterobacteriaceae family. It is a gastrointestinal pathogen of increasing notoriety, often associated with diarrheal disease. P. shigelloides is waterborne, and infection is often linked to the consumption of seafood. Here, we describe the first complete genome for P. shigelloides type strain NCTC10360. PMID:27660796
Cryptosporidiosis, giardiasis, and microsporidiosis are important waterborne diseases. In thestandard for wastewater treatment plant (WWTP) effluents in China and other countries, fecalcoliform is the only microbial indicator, raising concerns about the potential for pathogentransmission through WWPT effluent reuse. In this study, we collected 50 effluent samples(30 L/sample) from three municipal WWTPs in Shanghai, China and analyzed for Cryptosporidiumspp., Giardia duodenalis and Enterocytozoon bieneusi by microscopy and/or PCR. Moreover,propidium monoazide (PMA)-PCR was used to assess the viability of oocysts/cysts. The microscopyand PCR-positive rates for Cryptosporidium spp. were 62% and 40%, respectively. The occurrencerates of G. duodenalis were 96% by microscopy and 92??100% by PCR analysis of three genetic loci.Furthermore, E. bieneusi was detected in 70% (35/50) of samples by PCR. Altogether, tenCryptosporidium species or genotypes, two G. duodenalis genotypes, and 11 E. bieneusi genotypeswere found, most of which were human-pathogenic. The chlorine dioxide disinfection employed inWWTP1 and WWTP3 failed to inactivate the residual pathogens; 93% of the samples from WWTP1 and83% from WWTP3 did not meet the national standard on fecal coliform levels. Thus, urban WWTPeffluents often contain residual waterborne human pathogens.This dataset is associated with the following publication:Ma, J., Y. Feng, Y. Hu, E. Villegas , and L. Xiao. Human infective potentia
Interactions of Salmonella with animals and plants.
Wiedemann, Agnès; Virlogeux-Payant, Isabelle; Chaussé, Anne-Marie; Schikora, Adam; Velge, Philippe
2014-01-01
Salmonella enterica species are Gram-negative bacteria, which are responsible for a wide range of food- and water-borne diseases in both humans and animals, thereby posing a major threat to public health. Recently, there has been an increasing number of reports, linking Salmonella contaminated raw vegetables and fruits with food poisoning. Many studies have shown that an essential feature of the pathogenicity of Salmonella is its capacity to cross a number of barriers requiring invasion of a large variety of cells and that the extent of internalization may be influenced by numerous factors. However, it is poorly understood how Salmonella successfully infects hosts as diversified as animals or plants. The aim of this review is to describe the different stages required for Salmonella interaction with its hosts: (i) attachment to host surfaces; (ii) entry processes; (iii) multiplication; (iv) suppression of host defense mechanisms; and to point out similarities and differences between animal and plant infections.
Ahiwale, Sangeeta; Tagunde, Sujata; Khopkar, Sushama; Karni, Mrudula; Gajbhiye, Milind; Kapadnis, Balasaheb
2013-11-01
Water resources are contaminated by life-threatening multidrug resistant pathogenic bacteria. Unfortunately, these pathogenic bacteria do not respond to the traditional water purification methods. Therefore, there is a need of environmentally friendly strategies to overcome the problems associated with the antimicrobial resistant bacterial pathogens. In the present study, highly potent lytic phages against multidrug-resistant Salmonella enterica serovar Paratyphi B, Pseudomonas aeruginosa and Klebsiella pneumoniae were isolated from the Pavana river water. They belonged to the Podoviridae and Siphoviridae families. These phages were purified and enriched in the laboratory. Monovalent formulations of phiSPB, BVPaP-3 and KPP phages were prepared in three different liquids viz., phage broth, saline and distilled water. The phages were stable for almost 8-10 months in the phage broth at 4 degrees C. The stability of the phages in saline and distilled water was 5-6 months at 4 degrees C. All of the phages were stable only for 4-6 months in the phage broth at 30 degrees C. The monovalent phage formulation of psiSPB was applied at MOI < 1, as disinfectant against an exponential and stationary phase cells of Salmonella enterica serovar Paratyphi B in various water microcosms. The results indicated that there was almost 80 % reduction in the log phase cells of Salmonella serovar Paratyphi B in 24 h. In stationary phase cells, the reduction was comparatively less within same period. At the same time, there was concomitant increase in the phage population by 80% in all the microcosms indicating that psiSPB phage is highly potent in killing pathogen in water. Results strongly support that the formulation of psiSPB in the phage broth in monovalent form could be used as an effective biological disinfectant for preventing transmission of water-borne bacterial pathogens, including antimicrobial resistant ones.
Generalized reproduction numbers and the prediction of patterns in waterborne disease
Gatto, Marino; Mari, Lorenzo; Bertuzzo, Enrico; Casagrandi, Renato; Righetto, Lorenzo; Rodriguez-Iturbe, Ignacio; Rinaldo, Andrea
2012-01-01
Understanding, predicting, and controlling outbreaks of waterborne diseases are crucial goals of public health policies, but pose challenging problems because infection patterns are influenced by spatial structure and temporal asynchrony. Although explicit spatial modeling is made possible by widespread data mapping of hydrology, transportation infrastructure, population distribution, and sanitation, the precise condition under which a waterborne disease epidemic can start in a spatially explicit setting is still lacking. Here we show that the requirement that all the local reproduction numbers be larger than unity is neither necessary nor sufficient for outbreaks to occur when local settlements are connected by networks of primary and secondary infection mechanisms. To determine onset conditions, we derive general analytical expressions for a reproduction matrix , explicitly accounting for spatial distributions of human settlements and pathogen transmission via hydrological and human mobility networks. At disease onset, a generalized reproduction number (the dominant eigenvalue of ) must be larger than unity. We also show that geographical outbreak patterns in complex environments are linked to the dominant eigenvector and to spectral properties of . Tests against data and computations for the 2010 Haiti and 2000 KwaZulu-Natal cholera outbreaks, as well as against computations for metapopulation networks, demonstrate that eigenvectors of provide a synthetic and effective tool for predicting the disease course in space and time. Networked connectivity models, describing the interplay between hydrology, epidemiology, and social behavior sustaining human mobility, thus prove to be key tools for emergency management of waterborne infections. PMID:23150538
Wilhelm, Lance J.; Maluk, Terry L.
1998-01-01
IntroductionHigh levels of fecal-indicator bacteria in rivers and streams can indicate the possible presence of pathogenic (disease-causing) microorganisms. Cholera, typhoid fever, bacterial dysentery, infectious hepatitis, and cryptosporidiosis are some of the well known waterborne diseases that spread through water contaminated and fecal matter. Eye, ear, nose, and throat infections also can result from contact with contaminated water. In general, methods are not routinely used to detect pathogens in water. Instead, bacteria such as total coliforms, fecal coliforms, fecal streptococci, Escherichia coli (E coli), and enterococci are used as indicators of sanitary water quality, because they are present in high numbers in fecal material and have been shown to be associated with some waterborne disease-causing organisms. Indicator bacteria usually are harmless, more plentiful, and easier to detect than pathogens. The concentration of bacteria in a sample of water is usually expressed as the number of bacterial colonies per 100 milliliters of water sample.As part of the U.S. Geological Survey National Water-Quality Assessment Program, 145 samples were collected and analyzed for selected water-quality constituents, fecal coliforms, and fecal streptococci at 17 sites in North and South Carolina from October 1995 through September 1996. Of the original 17 sites, 4 in South Carolina were sampled for E. coli and total coliforms from April through September 1997. At two sites, this sampling continued from October 1997 through April 1998.
A novel spatially-explicit condition for the onset of waterborne diseases in complex environments
NASA Astrophysics Data System (ADS)
Mari, L.; Gatto, M.; Bertuzzo, E.; Casagrandi, R.; Righetto, L.; Rodriguez-Iturbe, I.; Rinaldo, A.
2012-12-01
In spatial models of waterborne infections the condition that all the local reproduction numbers be larger than one is neither necessary nor sufficient for outbreaks to occur. Here, to properly determine epidemic onset conditions, we examine the transition from stable to unstable of the disease-free equilibrium of a system of nonlinear differential equations characterizing the evolution of susceptible and infected individuals within their respective settlements, and pathogen concentration in their accessible environment. Two different network connectivity layers are assumed to link human settlements: hydrologic pathways serve as ecological corridors for pathogens, while human mobility acts as disease vehicle through susceptibles contracting the disease and asymptomatic infectives shedding bacteria at their temporary destinations. We show that an epidemic outbreak can be triggered if the dominant eigenvalue of a generalized reproduction matrix G0, suitably accounting for spatial distribution of human settlements, hydrological pathways for pathogen dispersal and pathogen redistribution mechanisms due to human mobility, is larger than unity. Matrix G0 and its dominant eigenvalue thus replace the usual reproduction number whenever spatial effects on disease propagation cannot be ignored. Conversely, our novel criterion decays into the standard onset condition based on local reproduction numbers in nonspatial settings. By analyzing realistic test cases we show that within a connected network system the disease can start even if all the local reproduction numbers are smaller than unity, or might not start even if all the local reproduction numbers are larger than unity. We also show that onset geography in complex environments is linked to the dominant eigenvector of matrix G0. Applications to cholera outbreaks in developing countries demonstrate that our approach can be successfully used for disease prediction and emergency management.
Butler, Ainslie J; Thomas, M Kate; Pintar, Katarina D M
2015-04-01
Enteric illness contributes to a significant burden of illness in Canada and globally. Understanding its sources is a critical step in identifying and preventing health risks. Expert elicitation is a powerful tool, used previously, to obtain information about enteric illness source attribution where information is difficult or expensive to obtain. Thirty-one experts estimated transmission of 28 pathogens via major transmission routes (foodborne, waterborne, animal contact, person-to-person, and other) at the point of consumption. The elicitation consisted of a (snowball) recruitment phase; administration of a pre-survey to collect background information, an introductory webinar, an elicitation survey, a 1-day discussion, survey readministration, and a feedback exercise, and surveys were administered online. Experts were prompted to quantify changes in contamination at the point of entry into the kitchen versus point of consumption. Estimates were combined via triangular probability distributions, and medians and 90% credible-interval estimates were produced. Transmission was attributed primarily to food for Bacillus cereus, Clostridium perfringens, Cyclospora cayetanensis, Trichinella spp., all three Vibrio spp. categories explored, and Yersinia enterocolitica. Multisource pathogens (e.g., transmitted commonly through both water and food) such as Campylobacter spp., four Escherichia coli categories, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus were also estimated as mostly foodborne. Water was the primary pathway for Giardia spp. and Cryptosporidium spp., and person-to-person transmission dominated for six enteric viruses and Shigella spp. Consideration of the point of attribution highlighted the importance of food handling and cross-contamination in the transmission pathway. This study provides source attribution estimates of enteric illness for Canada, considering all possible transmission routes. Further research is necessary to improve our understanding of poorly characterized pathogens such as sapovirus and E. coli subgroups in Canada.
USDA-ARS?s Scientific Manuscript database
Escherichia coli O157:H7 is a zoonotic pathogen that is an important cause of human food- and waterborne disease, with a spectrum of illnesses ranging from asymptomatic carriage and diarrhea to the sometimes fatal hemolytic uremic syndrome. Outbreaks of E. coli O157:H7 disease are frequently associ...
Ding, Zheyuan; Zhai, Yujia; Wu, Chen; Wu, Haocheng; Lu, Qinbao; Lin, Junfen; He, Fan
2017-06-01
In China, waterborne outbreaks of infectious diarrheal disease mainly occur in schools, and contaminated well water is a common source of pathogens. The objective of this review was to present the attack rates, durations of outbreak, pathogens of infectious diarrheal disease, and sanitary conditions of wells in primary and secondary schools in China, and to analyze risk factors and susceptibility of school children. Relevant articles and reports were identified by searching PubMed, Web of Science, China National Knowledge Infrastructure, China Information System for Disease Control and Prevention, and the Chinese Field Epidemiology Training Program. Essential information, including urban/rural areas, school types, attack rates, pathogens, durations of outbreak, report intervals, and interventions were extracted from the eligible articles. Wilcoxon signed-rank test, Kruskal-Wallis H test, and Spearman correlation test were conducted in statistical analyses. Sex- and age-specific attack rate ratios were calculated as pooled effect sizes. We screened 2188 articles and retrieved data of 85 outbreaks from 1987 to 2014. Attack rates of outbreaks in rural areas (median, 12.63 cases/100 persons) and in primary schools (median, 14.54 cases/100 persons) were higher than those in urban areas (median, 5.62 cases/100 persons) and in secondary schools (median, 8.74 cases/100 persons) (P = 0.004 and P = 0.013, respectively). Shigella, pathogenic Escherichia coli, and norovirus were the most common pathogens. Boys tended toward higher attack rates than girls (sex-specific attack rate ratio, 1.13; 95% CI, 1.00-1.29, P = 0.05). Unsanitary conditions of water wells were reported frequently, and unhealthy behavior habits were common in students. School children were susceptible to waterborne disease in China. Chinese government should make efforts to improve access to safe water in schools. Health education promotion and conscientiousness of school leaders and teachers should be enhanced. Copyright © 2017. Production and hosting by Elsevier B.V.
A Spike Cocktail Approach to Improve Microbial Performance Monitoring for Water Reuse.
Zimmerman, Brian D; Korajkic, Asja; Brinkman, Nichole E; Grimm, Ann C; Ashbolt, Nicholas J; Garland, Jay L
Water reuse, via either centralized treatment of traditional wastewater or decentralized treatment and on-site reuse, is becoming an increasingly important element of sustainable water management. Despite advances in waterborne pathogen detection methods, low and highly variable pathogen levels limit their utility for routine evaluation of health risks in water reuse systems. Therefore, there is a need to improve our understanding of the linkage between pathogens and more readily measured process indicators during treatment. This paper describes an approach for constructing spiking experiments to relate the behavior of viral, bacterial, and protozoan pathogens with relevant process indicators. General issues are reviewed, and the spiking protocol is applied as a case study example to improve microbial performance monitoring and health risk evaluation in a water reuse system. This approach provides a foundation for the development of novel approaches to improve real or near-real time performance monitoring of water recycling systems.
The threat of emerging infections.
1996-11-01
A variety of newly discovered pathogens and new forms of older infectious agents threaten to reemerge. Typical symptoms of acute infection are fever, headache, malaise, vomiting, and diarrhea. Some of the better-known emerging viral infections include dengue, filoviruses (Ebola, Marburg), hantaviruses, hepatitis B, hepatitis C, HIV, influenza, lassa fever, measles, rift valley fever, rotavirus, and yellow fever. Emerging bacterial infections include cholera, Escherichia coli 0157:H7, legionnaires disease (Legionella), lyme disease, streptococcus infections (group A), tuberculosis, and typhoid. Emerging parasitic infections include cryptosporidium and other waterborne pathogens and malaria. The causes of many diseases are still shrouded in mystery; thus, treatments and cures for them are as yet unknown.
Theron, Jacques; Eugene Cloete, Thomas; de Kwaadsteniet, Michele
2010-11-01
Waterborne microbial diseases are escalating worldwide increasing the need for powerful and sensitive diagnostics tools. Molecular methodologies, including immunological and nucleic acid-based methods, have only recently been applied in the water sector. Advances in nanotechnology and nanomaterials have opened the door for the development of new diagnostic tools with increased sensitivity and speed, and reduced cost and labor. Quantum dots, flo dots, gold nanoparticles, magnetic nanoparticles, carbon nanotubes, nanowires, and nanocantilevers, with their unique optical and physical properties, have already been applied in nanodiagnostics. Nanobiotechnology, once remaining technical and practical problems has been addressed, will play an important role in the detection of microbial pathogens.
Kostić, Tanja; Sessitsch, Angela
2011-01-01
Reliable and sensitive pathogen detection in clinical and environmental (including food and water) samples is of greatest importance for public health. Standard microbiological methods have several limitations and improved alternatives are needed. Most important requirements for reliable analysis include: (i) specificity; (ii) sensitivity; (iii) multiplexing potential; (iv) robustness; (v) speed; (vi) automation potential; and (vii) low cost. Microarray technology can, through its very nature, fulfill many of these requirements directly and the remaining challenges have been tackled. In this review, we attempt to compare performance characteristics of the microbial diagnostic microarrays developed for the detection and typing of food and water pathogens, and discuss limitations, points still to be addressed and issues specific for the analysis of food, water and environmental samples. PMID:27605332
A systematic review of waterborne disease burden methodologies from developed countries.
Murphy, H M; Pintar, K D M; McBean, E A; Thomas, M K
2014-12-01
The true incidence of endemic acute gastrointestinal illness (AGI) attributable to drinking water in Canada is unknown. Using a systematic review framework, the literature was evaluated to identify methods used to attribute AGI to drinking water. Several strategies have been suggested or applied to quantify AGI attributable to drinking water at a national level. These vary from simple point estimates, to quantitative microbial risk assessment, to Monte Carlo simulations, which rely on assumptions and epidemiological data from the literature. Using two methods proposed by researchers in the USA, this paper compares the current approaches and key assumptions. Knowledge gaps are identified to inform future waterborne disease attribution estimates. To improve future estimates, there is a need for robust epidemiological studies that quantify the health risks associated with small, private water systems, groundwater systems and the influence of distribution system intrusions on risk. Quantification of the occurrence of enteric pathogens in water supplies, particularly for groundwater, is needed. In addition, there are unanswered questions regarding the susceptibility of vulnerable sub-populations to these pathogens and the influence of extreme weather events (precipitation) on AGI-related health risks. National centralized data to quantify the proportions of the population served by different water sources, by treatment level, source water quality, and the condition of the distribution system infrastructure, are needed.
Electrochemical inactivation kinetics of boron-doped diamond electrode on waterborne pathogens.
Yao, Yanyan; Kubota, Yoshinobu; Murakami, Taketoshi; Ochiai, Tsuyoshi; Ishiguro, Hitoshi; Nakata, Kazuya; Fujishima, Akira
2011-09-01
A boron-doped diamond (BDD) electrode was constructed as a water disinfector for the inactivation of water borne pathogens. The bactericidal effect of the disinfector was evaluated on artificially contaminated waters containing, respectively, Escherichia coli, Pseudomonas aeruginosa and Legionella pneumophila at high density. By treating the bacterial suspensions with 4 V of constant voltage between the BDD and the counter-electrode for 50 min, the population of E. coli and P. aeruginosa decreased from (10E + 7-8 colony-forming unit mL(-1)) to below the detection limits of the colony-formation method. Meanwhile, L. pneumophila were reduced to virtually zero when analyzed by fluorescence-based staining. The influences of production parameters (voltage, NaCl concentration and flow rate) on the disinfection kinetics of the BDD disinfector were examined with respect to operational conditions. Voltage was the most significant factor for adjusting the extent of electrolysis, followed by NaCl concentration and flow rate, to influence the disinfection efficiency. The disinfection of natural river water samples containing numerous microbes was performed for a practicability investigation of the BDD electrode. Approximately 99.99% bactericidal efficiency was confirmed by viability detection for E. coli and common germs in treated water. The results showed that the BDD electrode is a promising tool for various wastewater disinfections to combat waterborne diseases.
Park, Jungsun; Kim, Jin Seok; Kim, Soojin; Shin, Eunkyung; Oh, Kyung-Hwan; Kim, Yonghoon; Kim, Cheon Hyeon; Hwang, Min Ah; Jin, Chan Mun; Na, Kyoungin; Lee, Jin; Cho, Enhi; Kang, Byung-Hak; Kwak, Hyo-Sun; Seong, Won Keun; Kim, Junyoung
2018-01-01
In June 2015, a local public health laboratory was notified that students had developed gastroenteritis symptoms after attending a camp. An outbreak investigation was conducted to determine the extent and cause of the outbreak. A retrospective cohort study was conducted to determine the correlations between the illness and specific exposures at the school camp. All attendees were interviewed with a standard questionnaire that addressed clinical symptoms, food consumption, and environmental exposures. Clinical specimens were cultured using standard microbiological methods for bacterial and viral pathogens. The genetic relationships of all isolates were determined using pulsed-field gel electrophoresis (PFGE). A total 188 patients with symptoms of diarrhoea, abdominal pain, and nausea were identified. The completed questionnaires suggested that the consumption of drinking water was likely to be linked to this outbreak. Using microbiological methods, enterohaemorrhagic Escherichia coli, enteropathogenic E. coli, and enteroaggregative E. coli were isolated, and the isolates from both patient stool and environmental water samples displayed indistinguishable XbaI-PFGE patterns. The water system in the camp used groundwater drawn from a private underground reservoir for cooking and drinking. The environmental investigation revealed some problems with the water supply system, such as the use of inappropriate filters in the water purifier and a defect in the pipeline between the reservoir and the chlorination device. This outbreak points to the importance of drinking water quality management in group facilities where underground water is used and emphasizes the need for periodic sanitation and inspection to prevent possible waterborne outbreaks. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Sherif, Mohsen
2010-07-01
Environmental problems and their potential impacts on public health vary in scale and time depending on the level and nature of pollutants. Although water is regarded as the source of all kinds of life on earth, it also acts as an efficient carrier of pollutants. Contamination of drinking water, agricultural water, or recreational water by infectious pathogens, chemical pollutants, or others can have significant impacts on public health. During the past few decades, waterborne diseases continued to spread and the health risks continued to increase. The correlation between water resources and public health is more evident in arid regions. This article discusses the availability of water resources in the Gulf Cooperation Council countries and elaborates on the possible impacts of water resources on public health. It emphasizes the importance of preservation of water quality and prevention of waterborne diseases, which could be achieved through a coordinated effort from diverse groups and disciplines.
Capelletti, Raquel Vannucci; Moraes, Ângela Maria
2016-02-01
Water is the main stimulus for the development of microorganisms, and its flow has an important role in the spreading of contaminants. In hospitals, the water distribution system requires special attention since it can be a source of pathogens, including those in the form of biofilms often correlated with resistance of microorganisms to various treatments. In this paper, information relevant to cases of nosocomial infections involving water circuits as a source of contaminants is compiled, with emphasis on the importance of microbiological control strategies to prevent the installation, spreading and growth of microorganisms in hospitals. An overview of the worldwide situation is provided, with emphasis on Brazilian hospitals. Different approaches normally used to control the occurrence of nosocomial infections due to waterborne contaminants are analyzed, and the use of the polysaccharide chitosan for this specific application is briefly discussed.
Generalized reproduction numbers and the prediction of patterns in waterborne disease.
Gatto, Marino; Mari, Lorenzo; Bertuzzo, Enrico; Casagrandi, Renato; Righetto, Lorenzo; Rodriguez-Iturbe, Ignacio; Rinaldo, Andrea
2012-11-27
Understanding, predicting, and controlling outbreaks of waterborne diseases are crucial goals of public health policies, but pose challenging problems because infection patterns are influenced by spatial structure and temporal asynchrony. Although explicit spatial modeling is made possible by widespread data mapping of hydrology, transportation infrastructure, population distribution, and sanitation, the precise condition under which a waterborne disease epidemic can start in a spatially explicit setting is still lacking. Here we show that the requirement that all the local reproduction numbers R0 be larger than unity is neither necessary nor sufficient for outbreaks to occur when local settlements are connected by networks of primary and secondary infection mechanisms. To determine onset conditions, we derive general analytical expressions for a reproduction matrix G0, explicitly accounting for spatial distributions of human settlements and pathogen transmission via hydrological and human mobility networks. At disease onset, a generalized reproduction number Λ0 (the dominant eigenvalue of G0) must be larger than unity. We also show that geographical outbreak patterns in complex environments are linked to the dominant eigenvector and to spectral properties of G0. Tests against data and computations for the 2010 Haiti and 2000 KwaZulu-Natal cholera outbreaks, as well as against computations for metapopulation networks, demonstrate that eigenvectors of G0 provide a synthetic and effective tool for predicting the disease course in space and time. Networked connectivity models, describing the interplay between hydrology, epidemiology, and social behavior sustaining human mobility, thus prove to be key tools for emergency management of waterborne infections.
Widerström, Micael; Schönning, Caroline; Lilja, Mikael; Lebbad, Marianne; Ljung, Thomas; Allestam, Görel; Ferm, Martin; Björkholm, Britta; Hansen, Anette; Hiltula, Jari; Långmark, Jonas; Löfdahl, Margareta; Omberg, Maria; Reuterwall, Christina; Samuelsson, Eva; Widgren, Katarina; Wallensten, Anders; Lindh, Johan
2014-04-01
In November 2010, ≈27,000 (≈45%) inhabitants of Östersund, Sweden, were affected by a waterborne outbreak of cryptosporidiosis. The outbreak was characterized by a rapid onset and high attack rate, especially among young and middle-aged persons. Young age, number of infected family members, amount of water consumed daily, and gluten intolerance were identified as risk factors for acquiring cryptosporidiosis. Also, chronic intestinal disease and young age were significantly associated with prolonged diarrhea. Identification of Cryptosporidium hominis subtype IbA10G2 in human and environmental samples and consistently low numbers of oocysts in drinking water confirmed insufficient reduction of parasites by the municipal water treatment plant. The current outbreak shows that use of inadequate microbial barriers at water treatment plants can have serious consequences for public health. This risk can be minimized by optimizing control of raw water quality and employing multiple barriers that remove or inactivate all groups of pathogens.
Schönning, Caroline; Lilja, Mikael; Lebbad, Marianne; Ljung, Thomas; Allestam, Görel; Ferm, Martin; Björkholm, Britta; Hansen, Anette; Hiltula, Jari; Långmark, Jonas; Löfdahl, Margareta; Omberg, Maria; Reuterwall, Christina; Samuelsson, Eva; Widgren, Katarina; Wallensten, Anders; Lindh, Johan
2014-01-01
In November 2010, ≈27,000 (≈45%) inhabitants of Östersund, Sweden, were affected by a waterborne outbreak of cryptosporidiosis. The outbreak was characterized by a rapid onset and high attack rate, especially among young and middle-aged persons. Young age, number of infected family members, amount of water consumed daily, and gluten intolerance were identified as risk factors for acquiring cryptosporidiosis. Also, chronic intestinal disease and young age were significantly associated with prolonged diarrhea. Identification of Cryptosporidium hominis subtype IbA10G2 in human and environmental samples and consistently low numbers of oocysts in drinking water confirmed insufficient reduction of parasites by the municipal water treatment plant. The current outbreak shows that use of inadequate microbial barriers at water treatment plants can have serious consequences for public health. This risk can be minimized by optimizing control of raw water quality and employing multiple barriers that remove or inactivate all groups of pathogens. PMID:24655474
NASA Astrophysics Data System (ADS)
Liu, L.; Fu, X.
2010-12-01
The US has very long shorelines (95,471 miles) contributing remarkable yearly revenue to the country by providing numerous recreational beaches. The beaches of both inland lakes and marine regions must be closed when the level of waterborne pathogens indicated by fecal indicator bacteria (FIB) including total coliform (TC), fecal coli form (FC, or Escherichia coli, E. coli) and Enterococcus exceed microbial water quality standards. Beach closures are of mounting concern to beach managers and the public due to the increasing risk to human health from waterborne pathogens. Monitoring FIB with laboratory analysis usually takes at least 18 hours during which beach goers may have been unintentionally exposed to the contaminated water. Therefore a water quality model to quickly and precisely forecast FIB has been a very effective tool for beach management to help beach managers in making decisions if beaches are safe enough to open to the public. The fate and transport of pathogens in the surf-zone of a beach area is a complex process involving various factors of hydrodynamics, hydrology, chemistry, microbiology. These factors including dispersion coefficient, wind velocity, particle settling velocity, fraction of bacteria attached, solar insolation, discharges to the beach, geometry of the beach, etc, are the essential components for a mechanistic model to describe the inactivation of FIB. To better understand the importance of these factors and their roles in impacting inactivation, transport and removal of FIB is extremely important to enhance the effectiveness and preciseness of a predictive model. The aim of this paper is to report the sensitivity analysis results of these factors in the surf zone of a creational beach using a verified water quality model system. The relative importance of these parameters is being ranked. For instance, the current sensitivity analysis shows that sunlight insolation has greater impact on pathogen inactivation than water temperature and settling velocity (figure 1). The analysis results and conclusion may provide indication for general beach management and further inactivation investigation of pathogens. Figure 1: Relative contributions of settling and solar insolation to the overall inactivation of E. coli at the Mt. Baldy Beach (Liu et al. 2006)
A Quick Response Forecasting Model of Pathogen Transport and Inactivation in Near-shore Regions
NASA Astrophysics Data System (ADS)
Liu, L.; Fu, X.
2011-12-01
Modeling methods supporting water quality assessments play a critical role by facilitating people to understand and promptly predict the potential threat of waterborne bacterial pathogens pose to human health. A mathematical model to describe and predict bacterial levels can provide foundation for water managers in making decisions on whether a water system is safe to open to the public. The inactivation (decay or die-off) rate of bacteria is critical in a bacterial model by controlling bacterial concentration in waters and depends on numerous factors of hydrodynamics, meteorology, geology, chemistry and biology. Transport and fate of waterborne pathogens in fresh water systems is an essentially three-dimensional problem, which requires a coupling of hydrodynamic equations and transport equations that describe the pathogen and suspended sediment dynamics. However, such an approach could be very demanding and time consuming from a practical point of view due to excess computational efforts. Long computation time may lead people unintentionally drinking or swimming in the contaminated water during the period before the predictive results of water quality come out. Therefore, it is very necessary to find a quick-response model to forecast bacterial concentration instantly to protect human health without any delay. Nearshore regions are the most commonly and directly used area for people in a huge water system. The prior multi-dimensional investigations of E. Coli and Enterococci inactivation in literature indicate that along-shore current predominated the nearshore region. Consequently, the complex dynamic conditions may be potentially simplified to one-dimensional scenario. In this research, a one-dimensional model system coupling both hydrodynamic and bacterial transport modules is constructed considering different complex processes to simulate the transport and fate of pathogens in nearshore regions. The quick-response model mainly focuses on promptly forecasting purpose and will be verified and calibrated with the available data collected from southern Lake Michigan. The modeling results will be compared with those from prior multi-dimensional models. This model is specifically effective for the outfall-controlled waters, where pathogens are primarily predominated by loadings from nearby tributaries and tend to show wide variations in concentrations.
Nanocomposite copolymer thin-film sensor for detection of escherichia coli
NASA Astrophysics Data System (ADS)
Mathur, Prafull; Misra, S. C. K.; Yadav, Maneesha; Bawa, S. S.; Gupta, A. K.
2006-01-01
The majority of human diseases associated with microbial contaminated water are infectious in nature and the associated pathogen includes bacteria, fungi, viruses and protozoa. Water contaminated with bacteria can cause a number of food-borne and water-borne diseases. The waterborne transmission is highly effective means of spreading infectious agents to a large portion of population; this includes water and milk too. Waterborne infections are recognized as resulting either from ingestion of contaminated water or ice, food items, which have, came into contact with microbial contaminated water (occurring through bathing and recreational activities) etc. The detection of E. coli in food and water is normally carried out by culturing methods, which normally take 3-6 days, These methods are complicated and time-consuming in spite of their correctness, and cannot easily meet inspection demands on E. coli. Hence, an establishment of rapid detection methods for E. coli is strongly required. We have developed highly sensitive and cost effective solid sate sensors prepared from vacuum evaporated thin films of nanocomposite copolymer detection of presence of E. coli vapors in the air within 20 seconds. These sensors operate at room temperature. The preparation, optical, electrical, and structural characterization and behavioral acceptance test on the microorganism sensing properties of these sensors are reported here.
Bartholomew, Nadia; Brunton, Cheryl; Mitchell, Peter; Williamson, Judy; Gilpin, Brent
2014-09-01
Outbreaks of waterborne gastroenteritis continue to occur in developed countries. Darfield, a rural town in the South Island of New Zealand experienced an outbreak of campylobacteriosis following a transgression of Escherichia coli on 16 August 2012. A descriptive outbreak investigation was performed. As a result, 29 cases had a laboratory-confirmed diagnosis of campylobacteriosis and 138 were identified as probable cases. Heavy rains, contamination of water with animal effluent from nearby paddocks and failures in the treatment of drinking water led to pathogens being distributed through the town's water supply. A multi-barrier approach is advocated to ensure the quality of water and many countries have legislation or programmes to address this. Although legislation for water safety plans based on a multi-barrier approach is in place in New Zealand, at the time of the outbreak it was not a requirement for the Darfield water supply. In addition, despite the awareness of the importance of a multi-barrier approach, competing interests, including those from the agricultural industry and financial restraints on water suppliers, can prevent it from being implemented. Governments need to be more willing to enforce legislation and standards to protect the public from waterborne disease.
Extreme water-related weather events and waterborne disease.
Cann, K F; Thomas, D Rh; Salmon, R L; Wyn-Jones, A P; Kay, D
2013-04-01
Global climate change is expected to affect the frequency, intensity and duration of extreme water-related weather events such as excessive precipitation, floods, and drought. We conducted a systematic review to examine waterborne outbreaks following such events and explored their distribution between the different types of extreme water-related weather events. Four medical and meteorological databases (Medline, Embase, GeoRef, PubMed) and a global electronic reporting system (ProMED) were searched, from 1910 to 2010. Eighty-seven waterborne outbreaks involving extreme water-related weather events were identified and included, alongside 235 ProMED reports. Heavy rainfall and flooding were the most common events preceding outbreaks associated with extreme weather and were reported in 55·2% and 52·9% of accounts, respectively. The most common pathogens reported in these outbreaks were Vibrio spp. (21·6%) and Leptospira spp. (12·7%). Outbreaks following extreme water-related weather events were often the result of contamination of the drinking-water supply (53·7%). Differences in reporting of outbreaks were seen between the scientific literature and ProMED. Extreme water-related weather events represent a risk to public health in both developed and developing countries, but impact will be disproportionate and likely to compound existing health disparities.
Robertson, Suzanne L; Eisenberg, Marisa C; Tien, Joseph H
2013-01-01
Many factors influencing disease transmission vary throughout and across populations. For diseases spread through multiple transmission pathways, sources of variation may affect each transmission pathway differently. In this paper we consider a disease that can be spread via direct and indirect transmission, such as the waterborne disease cholera. Specifically, we consider a system of multiple patches with direct transmission occurring entirely within patch and indirect transmission via a single shared water source. We investigate the effect of heterogeneity in dual transmission pathways on the spread of the disease. We first present a 2-patch model for which we examine the effect of variation in each pathway separately and propose a measure of heterogeneity that incorporates both transmission mechanisms and is predictive of R(0). We also explore how heterogeneity affects the final outbreak size and the efficacy of intervention measures. We conclude by extending several results to a more general n-patch setting.
Using Fluorescent Viruses for Detecting Bacteria in Water
NASA Technical Reports Server (NTRS)
Tabacco, Mary Beth; Qian, Xiaohua; Russo, Jaimie A.
2009-01-01
A method of detecting water-borne pathogenic bacteria is based partly on established molecular-recognition and fluorescent-labeling concepts, according to which bacteria of a species of interest are labeled with fluorescent reporter molecules and the bacteria can then be detected by fluorescence spectroscopy. The novelty of the present method lies in the use of bacteriophages (viruses that infect bacteria) to deliver the fluorescent reporter molecules to the bacteria of the species of interest.
Rhodes, Eric R.; Villegas, Leah Fohl; Shaw, Nancy J.; Miller, Carrie; Villegas, Eric N.
2012-01-01
Cryptosporidium and Giardia species are two of the most prevalent protozoa that cause waterborne diarrheal disease outbreaks worldwide. To better characterize the prevalence of these pathogens, EPA Method 1623 was developed and used to monitor levels of these organisms in US drinking water supplies 12. The method has three main parts; the first is the sample concentration in which at least 10 L of raw surface water is filtered. The organisms and trapped debris are then eluted from the filter and centrifuged to further concentrate the sample. The second part of the method uses an immunomagnetic separation procedure where the concentrated water sample is applied to immunomagnetic beads that specifically bind to the Cryptosporidium oocysts and Giardia cysts allowing for specific removal of the parasites from the concentrated debris. These (oo)cysts are then detached from the magnetic beads by an acid dissociation procedure. The final part of the method is the immunofluorescence staining and enumeration where (oo)cysts are applied to a slide, stained, and enumerated by microscopy. Method 1623 has four listed sample concentration systems to capture Cryptosporidium oocysts and Giardia cysts in water: Envirochek filters (Pall Corporation, Ann Arbor, MI), Envirochek HV filters (Pall Corporation), Filta-Max filters (IDEXX, Westbrook, MA), or Continuous Flow Centrifugation (Haemonetics, Braintree, MA). However, Cryptosporidium and Giardia (oo)cyst recoveries have varied greatly depending on the source water matrix and filters used1,14. A new tangential flow hollow-fiber ultrafiltration (HFUF) system has recently been shown to be more efficient and more robust at recovering Cryptosporidium oocystsand Giardia cysts from various water matrices; moreover, it is less expensive than other capsule filter options and can concentrate multiple pathogens simultaneously1-3,5-8,10,11. In addition, previous studies by Hill and colleagues demonstrated that the HFUF significantly improved Cryptosporidium oocysts recoveries when directly compared with the Envirochek HV filters4. Additional modifications to the current methods have also been reported to improve method performance. Replacing the acid dissociation procedure with heat dissociation was shown to be more effective at separating Cryptosporidium from the magnetic beads in some matrices9,13 . This protocol describes a modified Method 1623 that uses the new HFUF filtration system with the heat dissociation step. The use of HFUF with this modified Method is a less expensive alternative to current EPA Method 1623 filtration options and provides more flexibility by allowing the concentration of multiple organisms. PMID:22805201
Meng, Xiao-Lin; Li, Shuai; Qin, Chao-Bin; Zhu, Zhen-Xiang; Hu, Wen-Pan; Yang, Li-Ping; Lu, Rong-Hua; Li, Wen-Jun; Nie, Guo-Xing
2018-09-30
The present study was conducted to determine the effects of waterborne copper exposure on the lipid metabolism and intestinal microbiota of juvenile common carp (Cyprinus carpio L.). Common carp were exposed to four waterborne copper (Cu) concentrations (0 (control), 0.07 (low), 0.14 (medium), and 0.28 (high) mg Cu/L) for 8 weeks. Exposure to a high concentration of Cu had a negative effect on growth indices (weight gain rate (WGR) and specific growth rate (SGR)). The biochemical indices measured in serum (low-density lipoprotein (LDL) and triglycerides (TGs)) were significantly affected by exposure to medium concentration levels of Cu. The mRNA levels of lipogenic enzymes (acetyl-CoA carboxylase 1 (ACC-1) and fatty acid synthase (FAS)) and sterol-regulator element-binding protein-1 (SREBP-1) in liver tissue and tight binding protein genes (ZO-1 and occludin) in intestinal epithelial tissue were significantly downregulated in the 0.14 and 0.28 mg/L Cu treatment groups, accompanied by upregulated mRNA levels of lipolysis enzymes (lipoprotein lipase (LPL) and carnitine palmitoyl transferase 1 (CPT-1)) in the liver. The data also showed that the composition of intestinal microbiota was changed following Cu exposure and could alter the α-diversity and β-diversity. The abundances of few putative short-chain fatty acid (SCFA)-producing bacteria, including Allobaculum, Blautia, Coprococcus, Faecalibacterium, Roseburia, and Ruminococcus, decreased significantly. More specifically, Roseburia sequences were positively associated with lipogenic enzymes, total protein (TP), and TGs and negatively associated with lipolysis enzymes. Other sequences related to probiotics (Lactobacillus, Bacillus and Akkermansia) were also found to decrease, accompanied by an increase in sequences related to pathogens (Pseudomonas and Acinetobacter). To the best of our knowledge, the present study provides the first evidence that waterborne, chronic Cu exposure can disturb the composition of intestinal microbiota related to lipid metabolism and immunity in freshwater fish, thereby increasing the risk of pathogen invasion. Copyright © 2018 Elsevier Inc. All rights reserved.
Seasonality, Water Quality Variability and Diarrheal Disease in Northern Coastal Ecuador
NASA Astrophysics Data System (ADS)
Levy, K.; Hubbard, A. E.; Nelson, K. L.; Eisenberg, J. N.
2008-12-01
Objective Seasonality plays a key role in determining incidence of infectious diseases. Diarrheal diseases in particular show seasonal trends, with bacterial pathogens usually peaking in warmer months and viral pathogens peaking in cooler, dryer months. However, studies of the impacts of water quality on diarrheal disease are usually undertaken cross-sectionally, over a short period of time. In this study, we explore how seasonality affects diarrheal disease incidence in a rural area of northern coastal Ecuador, using longer-term datasets. Materials and Methods We use water quality data (as measured by E.coli counts) for both source and in-home water samples collected on a weekly basis over the course of one year in one village. We test the relationship between weekly variability in water quality and diarrheal disease incidence, water treatment and water storage practices in the home. Results We find that peaks in geometric mean values of microbial contamination of source waters often correspond to peaks in weekly village diarrhea incidence in the wet season, but not in the dry season. We also find that perceptions of villagers about water cleanliness do not correspond to levels of microbial contamination; people are more likely to treat their water in the dry season, whereas microbial contamination of source waters peaks in the wet season. We relate these findings to a broader analysis of the relationship between weekly rainfall and diarrheal disease incidence in 21 villages across a larger region over the course of five years. Conclusions Our findings suggest that seasonal variability plays a role in the relationship between water quality and waterborne disease. A consideration of seasonality can help guide public health interventions, by targeting messages about water treatment at times when people are most at risk for waterborne disease. These data can also help inform projections of the impact of climate change on waterborne disease.
Zhang, Yu; Chen, Zhimin; An, Wei; Xiao, Shumin; Yuan, Hongying; Zhang, Dongqing; Yang, Min
2015-04-01
Membrane bioreactors (MBR) are highly efficient at intercepting particles and microbes and have become an important technology for wastewater reclamation. However, many pathogens can accumulate in activated sludge due to the long residence time usually adopted in MBR, and thus may pose health risks when membrane integrity problems occur. This study presents data from a survey on the occurrence of water-borne Giardia pathogens in reclaimed water from a full-scale wastewater treatment plant with MBR experiencing membrane integrity failure, and assessed the associated risk for green space irrigation. Due to membrane integrity failure, the MBR effluent turbidity varied between 0.23 and 1.90 NTU over a period of eight months. Though this turbidity level still met reclaimed water quality standards (≤5 NTU), Giardia were detected at concentrations of 0.3 to 95 cysts/10 L, with a close correlation between effluent turbidity and Giardia concentration. All β-giardin gene sequences of Giardia in the WWTP influents were genotyped as Assemblages A and B, both of which are known to infect humans. An exponential dose-response model was applied to assess the risk of infection by Giardia. The risk in the MBR effluent with chlorination was 9.83×10(-3), higher than the acceptable annual risk of 1.0×10(-4). This study suggested that membrane integrity is very important for keeping a low pathogen level, and multiple barriers are needed to ensure the biological safety of MBR effluent. Copyright © 2015. Published by Elsevier B.V.
A rapid two dot filter assay for the detection of E. coli O157 in water samples.
Kamma, Sujatha; Tang, Lily; Leung, Kelvin; Ashton, Edie; Newman, Norman; Suresh, Mavanur R
2008-07-31
E. coli O157:H7 is an enterohemorrhagic bacteria that cause deadly water-borne infections implicated in outbreaks of a wide spectrum of human gastrointestinal diseases. It is therefore important to have a rapid convenient, simple and sensitive range of detection of E. coli O157:H7. A new E. coli O157 MAb designated P124 was developed for ultrasensitive detection of E. coli O157 in water, apple juice and beef for routine use. A prototype filter dot assay was designed with anti-E. coli O157 MAb bound to 0.2 microm nitrocellulose filter disk as the capture antibody. A 100 ml water sample spiked with 1-50 CFU of E. coli O157 either in the presence or absence of other non-specific bacteria were filtered for capture of the pathogen on the antibody coated nitrocellulose disk. The detection of the pathogen was successfully accomplished by the same antibody both as a capture and detecting antibody as a homosandwich. In a non-enriched format, detection of E. coli was possible with a sensitivity of 2500 CFU/100 ml. Ultrasensitive detection of ~1 CFU/100 ml sample could be achieved by a prior pathogen enrichment step before the addition of the labeled antibody. The design of this diagnostic test is based on the common architecture of all bacteria, viruses and spores, namely the manifestation of repeat lipopolysaccharide epitopes on the surface. We have developed an easy-to-use two dot visual filter assay for translation into current water testing in public health laboratories to detect E. coli O157:H7. In a 5 h assay approximately 1 CFU and approximately 5 CFU of E. coli O157 could be detected in 100 ml of water or juice and lake samples respectively. This simple homosandwich enrichment strategy can also be used to detect low levels of other water-borne pathogens.
Immunity to intestinal pathogens: lessons learned from Salmonella
McSorley, Stephen J.
2014-01-01
Summary Salmonella are a common source of food or water-borne infection and cause a wide range of clinical disease in human and animal hosts. Salmonella are relatively easy to culture and manipulate in a laboratory setting, and the infection of laboratory animals induces robust innate and adaptive immune responses. Thus, immunologists have frequently turned to Salmonella infection models to expand understanding of immunity to intestinal pathogens. In this review, I summarize current knowledge of innate and adaptive immunity to Salmonella and highlight features of this response that have emerged from recent studies. These include the heterogeneity of the antigen-specific T-cell response to intestinal infection, the prominence of microbial mechanisms to impede T and B-cell responses, and the contribution of non-cognate pathways for elicitation of T-cell effector functions. Together, these different issues challenge an overly simplistic view of host-pathogen interaction during mucosal infection but also allow deeper insight into the real-world dynamic of protective immunity to intestinal pathogens. PMID:24942689
Bopp, Dianna J.; Sauders, Brian D.; Waring, Alfred L.; Ackelsberg, Joel; Dumas, Nellie; Braun-Howland, Ellen; Dziewulski, David; Wallace, Barbara J.; Kelly, Molly; Halse, Tanya; Musser, Kimberlee Aruda; Smith, Perry F.; Morse, Dale L.; Limberger, Ronald J.
2003-01-01
The largest reported outbreak of waterborne Escherichia coli O157:H7 in the United States occurred in upstate New York following a county fair in August 1999. Culture methods were used to isolate E. coli O157:H7 from specimens from 128 of 775 patients with suspected infections. Campylobacter jejuni was also isolated from stools of 44 persons who developed diarrheal illness after attending this fair. There was one case of a confirmed coinfection with E. coli O157:H7 and C. jejuni. Molecular detection of stx1 and stx2 Shiga toxin genes, immunomagnetic separation (IMS), and selective culture enrichment were utilized to detect and isolate E. coli O157:H7 from an unchlorinated well and its distribution points, a dry well, and a nearby septic tank. PCR for stx1 and stx2 was shown to provide a useful screen for toxin-producing E. coli O157:H7, and IMS subculture improved recovery. Pulsed-field gel electrophoresis (PFGE) was used to compare patient and environmental E. coli O157:H7 isolates. Among patient isolates, 117 of 128 (91.5%) were type 1 or 1a (three or fewer bands different). Among the water distribution system isolates, 13 of 19 (68%) were type 1 or 1a. Additionally, PFGE of C. jejuni isolates revealed that 29 of 35 (83%) had indistinguishable PFGE patterns. The PFGE results implicated the water distribution system as the main source of the E. coli O157:H7 outbreak. This investigation demonstrates the potential for outbreaks involving more than one pathogen and the importance of analyzing isolates from multiple patients and environmental samples to develop a better understanding of bacterial transmission during an outbreak. PMID:12517844
A true real-time, on-line security system for waterborne pathogen surveillance
NASA Astrophysics Data System (ADS)
Adams, John A.; McCarty, David L.
2008-04-01
Over the past several years many advances have been made to monitor potable water systems for toxic threats. However, the need for real-time, on-line systems to detect the malicious introduction of deadly pathogens still exists. Municipal water distribution systems, government facilities and buildings, and high profile public events remain vulnerable to terrorist-related biological contamination. After years of research and development, an instrument using multi-angle light scattering (MALS) technology has been introduced to achieve on-line, real-time detection and classification of a waterborne pathogen event. The MALS system utilizes a continuous slip stream of water passing through a flow cell in the instrument. A laser beam, focused perpendicular to the water flow, strikes particles as they pass through the beam generating unique light scattering patterns that are captured by photodetectors. Microorganisms produce patterns termed 'bio-optical signatures' which are comparable to fingerprints. By comparing these bio-optical signatures to an on-board database of microorganism patterns, detection and classification occurs within minutes. If a pattern is not recognized, it is classified as an 'unknown' and the unidentified contaminant is registered as a potential threat. In either case, if the contaminant exceeds a customer's threshold, the system will immediately alert personnel to the contamination event while extracting a sample for confirmation. The system, BioSentry TM, developed by JMAR Technologies is now field-tested and commercially available. BioSentry is cost effective, uses no reagents, operates remotely, and can be used for continuous microbial surveillance in many water treatment environments. Examples of HLS installations will be presented along with data from the US EPA NHSRC Testing and Evaluation Facility.
Influence of air quality on the composition of microbial pathogens in fresh rainwater.
Kaushik, Rajni; Balasubramanian, Rajasekhar; de la Cruz, Armah A
2012-04-01
In this study, the microbiological quality of fresh rainwater was assessed from 50 rain events under tropical weather conditions for a year. The levels of four major opportunistic waterborne pathogens, namely, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Aeromonas hydrophila, in rainwater samples were quantified by using a robust and sensitive quantitative PCR (qPCR) method. Of the 50 rainwater samples, 25 were found to be positive for at least one pathogen: 21 for E. coli, 16 for P. aeruginosa, 6 for K. pneumoniae, and 1 for A. hydrophila. In addition to the microbiological assessment of rainwater samples, we also studied the influence of prevailing air quality on the microbial quality of rainwater over the sampling period. A significant change in the diversity and relative abundance of the basic microbial indicator organisms in rainwater was observed during a major regional air pollution episode in Southeast Asia due to biomass-burning emissions.
Zhao, Xinyan; Dong, Tao
2013-01-01
Bacterial waterborne pathogens often threaten the water safety of the drinking water system. In order to protect the health of home users, a household lab-on-a-chip (LOC) device was developed for online monitoring bacterial pathogens in drinking water, which are in accord with green design concept. The chip integrated counter-flow micromixers, a T-junction droplet generator and time-delay channels (TD-Cs), which can mix water sample and reactants into droplets in air flow and incubate the droplets in the LOC for about 18 hours before observation. The detection module was simplified into a transparent observation chamber, from which the home users can evaluate the qualitative result by naked eyes. The liquid waste generated by the LOC system was sterilized and absorbed by quicklime powders. No secondary pollution was found. The preliminary test of the prototype system met its design requirements.
Bacteriophage-Based Pathogen Detection
NASA Astrophysics Data System (ADS)
Ripp, Steven
Considered the most abundant organism on Earth, at a population approaching 1031, bacteriophage, or phage for short, mediate interactions with myriad bacterial hosts that has for decades been exploited in phage typing schemes for signature identification of clinical, food-borne, and water-borne pathogens. With over 5,000 phage being morphologically characterized and grouped as to susceptible host, there exists an enormous cache of bacterial-specific sensors that has more recently been incorporated into novel bio-recognition assays with heightened sensitivity, specificity, and speed. These assays take many forms, ranging from straightforward visualization of labeled phage as they attach to their specific bacterial hosts to reporter phage that genetically deposit trackable signals within their bacterial hosts to the detection of progeny phage or other uniquely identifiable elements released from infected host cells. A comprehensive review of these and other phage-based detection assays, as directed towards the detection and monitoring of bacterial pathogens, will be provided in this chapter.
The Wisconsin State Laboratory of Hygiene and emerging enteric pathogens.
Warshauer, David; Monson, Tim; Kurzynski, Terry
2003-01-01
At the turn of the 20th century, typhoid fever was common in Wisconsin, and was a major impetus for the establishment of the Wisconsin State Laboratory of Hygiene (WSLH) in 1903. By the 1940s, typhoid was virtually eliminated in the United States due to public health measures such as disinfection of drinking water, sewage treatment, pasteurization, and shellfish bed sanitation. However, new food and waterborne pathogens have emerged to take the place of Salmonella Typhi. Infections with non-typhoidal Salmonella strains in the United States have increased almost 10-fold since the 1950s. In the last 20 years, the emergence of foodborne pathogens, such as Escherichia coli O157:H7, Cyclospora cayetanensis, Noroviruses (Norwalk-like viruses), Cryptosporidium parvum, Campylobacter jejuni, Yersinia enterocolitica, and multi-drug-resistant Salmonella, has identified a need for accurate laboratory diagnosis of enteric disease and outbreaks.
Collender, Philip A.; Cooke, Olivia C.; Bryant, Lee D.; Kjeldsen, Thomas R.; Remais, Justin V.
2017-01-01
Flooding is known to facilitate infectious disease transmission, yet quantitative research on microbiological risks associated with floods has been limited. Pathogen fate and transport models provide a framework to examine interactions between landscape characteristics, hydrology, and waterborne disease risks, but have not been widely developed for flood conditions. We critically examine capabilities of current hydrological models to represent unusual flow paths, non-uniform flow depths, and unsteady flow velocities that accompany flooding. We investigate the theoretical linkages between hydrodynamic processes and spatio-temporally variable suspension and deposition of pathogens from soils and sediments; pathogen dispersion in flow; and concentrations of constituents influencing pathogen transport and persistence. Identifying gaps in knowledge and modeling practice, we propose a research agenda to strengthen microbial fate and transport modeling applied to inland floods: 1) development of models incorporating pathogen discharges from flooded sources (e.g., latrines), effects of transported constituents on pathogen persistence, and supply-limited pathogen transport; 2) studies assessing parameter identifiability and comparing model performance under varying degrees of process representation, in a range of settings; 3) development of remotely sensed datasets to support modeling of vulnerable, data-poor regions; and 4) collaboration between modelers and field-based researchers to expand the collection of useful data in situ. PMID:28757789
NASA Astrophysics Data System (ADS)
Baeza, Andrés; Estrada-Barón, Alejandra; Serrano-Candela, Fidel; Bojórquez, Luis A.; Eakin, Hallie; Escalante, Ana E.
2018-06-01
Due to unplanned growth, large extension and limited resources, most megacities in the developing world are vulnerable to hydrological hazards and infectious diseases caused by waterborne pathogens. Here we aim to elucidate the extent of the relation between the spatial heterogeneity of physical and socio-economic factors associated with hydrological hazards (flooding and scarcity) and the spatial distribution of gastrointestinal disease in Mexico City, a megacity with more than 8 million people. We applied spatial statistics and multivariate regression analyses to high resolution records of gastrointestinal diseases during two time frames (2007–2009 and 2010–2014). Results show a pattern of significant association between water flooding events and disease incidence in the city center (lowlands). We also found that in the periphery (highlands), higher incidence is generally associated with household infrastructure deficiency. Our findings suggest the need for integrated and spatially tailored interventions by public works and public health agencies, aimed to manage socio-hydrological vulnerability in Mexico City.
Concentration and separation of biological organisms by ultrafiltration and dielectrophoresis
Simmons, Blake A.; Hill, Vincent R.; Fintschenko, Yolanda; Cummings, Eric B.
2010-10-12
Disclosed is a method for monitoring sources of public water supply for a variety of pathogens by using a combination of ultrafiltration techniques together dielectrophoretic separation techniques. Because water-borne pathogens, whether present due to "natural" contamination or intentional introduction, would likely be present in drinking water at low concentrations when samples are collected for monitoring or outbreak investigations, an approach is needed to quickly and efficiently concentrate and separate particles such as viruses, bacteria, and parasites in large volumes of water (e.g., 100 L or more) while simultaneously reducing the sample volume to levels sufficient for detecting low concentrations of microbes (e.g., <10 mL). The technique is also designed to screen the separated microbes based on specific conductivity and size.
Sensors Provide Early Warning of Biological Threats
NASA Technical Reports Server (NTRS)
2009-01-01
Early Warning Inc. of Troy, New York, licensed powerful biosensor technology from Ames Research Center. Incorporating carbon nanotubes tipped with single strands of nucleic acid from waterborne pathogens, the sensor can detect even minute amounts of targeted, disease causing bacteria, viruses, and parasites. Early Warning features the NASA biosensor in its water analyzer, which can provide advance alert of potential biological hazards in water used for agriculture, food and beverages, showers, and at beaches and lakes -- within hours instead of the days required by conventional laboratory methods.
Drinking water disinfection has effectively eliminated much of the morbidity and mortality associated with waterborne infectious diseases in the United States. Various disinfection processes, however, produce certain types and amounts of disinfection by-products (DBPs), including...
NASA Astrophysics Data System (ADS)
Bucci, Antonio; Petrella, Emma; Celico, Fulvio; Naclerio, Gino
2017-06-01
Waterborne pathogens represent a significant health risk in both developed and developing countries with sensitive sub-populations including children, the elderly, neonates, and immune-compromised people, who are particularly susceptible to enteric infections. Annually, approximately 1.8 billion people utilize a faecally contaminated water source, and waterborne diseases are resulting in up to 2.1 million human mortalities globally. Although groundwater has traditionally been considered less susceptible to contamination by enteric pathogens than surface water due to natural attenuation by overlying strata, the degree of microbial removal attributable to soils and aquifers can vary significantly depending on several factors. Thus, accurate assessment of the variable presence and concentration of microbial contaminants, and the relative importance of potentially causative factors affecting contaminant ingress, is critical in order to develop effective source (well) and resource (aquifer) protection strategies. "Traditional" and molecular microbiological study designs, when coupled with hydrogeological, hydrochemical, isotopic, and geophysical methods, have proven useful for analysis of numerous aspects of subsurface microbial dynamics. Accordingly, this overview paper presents the principal microbial techniques currently being employed (1) to predict and identify sources of faecal contamination in groundwater, (2) to elucidate the dynamics of contaminant migration, and (3) to refine knowledge about the hydrogeological characteristics and behaviours of aquifer systems affected by microbial contamination with an emphasis on carbonate aquifers, which represent an important global water supply. Previous investigations carried out in carbonate aquifers in southern Italy are discussed.
Beeman, Michael G; Nze, Ugochukwu C; Sant, Himanshu J; Malik, Hammad; Mohanty, Swomitra; Gale, Bruce K; Carlson, Krista
2018-05-10
The availability of clean drinking water is a significant problem worldwide. Many technologies exist for purifying drinking water, however, many of these methods require chemicals or use simple methods, such as boiling and filtering, which may or may not be effective in removing waterborne pathogens. Present methods for detecting pathogens in point-of-use (POU) sterilized water are typically time prohibitive or have limited ability differentiating between active and inactive cells. This work describes a rapid electrochemical sensor to differentially detect the presence of active Escherichia coli (E. coli) O157:H7 in samples that have been partially or completely sterilized using a new POU electrocatalytic water purification technology based on superradicals generated by defect laden titania (TiO₂) nanotubes. The sensor was also used to detect pathogens sterilized by UV-C radiation for a comparison of different modes of cell death. The sensor utilizes immunomagnetic bead separation to isolate active bacteria by forming a sandwich assay comprised of antibody functionalized secondary magnetic beads, E. coli O157:H7, and polyguanine (polyG) oligonucleotide functionalized secondary polystyrene beads as an electrochemical tag. The assay is formed by the attachment of antibodies to active receptors on the membrane of E. coli , allowing the sensor to differentially detect viable cells. Ultravioloet (UV)-C radiation and an electrocatalytic reactor (ER) with integrated defect-laden titania nanotubes were used to examine the sensors’ performance in detecting sterilized cells under different modes of cell death. Plate counts and flow cytometry were used to quantify disinfection efficacy and cell damage. It was found that the ER treatments shredded the bacteria into multiple fragments, while UV-C treatments inactivated the bacteria but left the cell membrane mostly intact.
Broadly Protective Shigella Vaccine Based on Type III Secretion Apparatus Proteins
Martinez-Becerra, Francisco J.; Kissmann, Julian M.; Diaz-McNair, Jovita; Choudhari, Shyamal P.; Quick, Amy M.; Mellado-Sanchez, Gabriela; Clements, John D.
2012-01-01
Shigella spp. are food- and waterborne pathogens that cause severe diarrheal and dysenteric disease associated with high morbidity and mortality. Individuals most often affected are children under 5 years of age in the developing world. The existence of multiple Shigella serotypes and the heterogenic distribution of pathogenic strains, as well as emerging antibiotic resistance, require the development of a broadly protective vaccine. All Shigella spp. utilize a type III secretion system (TTSS) to initiate infection. The type III secretion apparatus (TTSA) is the molecular needle and syringe that form the energized conduit between the bacterial cytoplasm and the host cell to transport effector proteins that manipulate cellular processes to benefit the pathogen. IpaB and IpaD form a tip complex atop the TTSA needle and are required for pathogenesis. Because they are common to all virulent Shigella spp., they are ideal candidate antigens for a subunit-based, broad-spectrum vaccine. We examined the immunogenicity and protective efficacy of IpaB and IpaD, alone or combined, coadministered with a double mutant heat-labile toxin (dmLT) from Escherichia coli, used as a mucosal adjuvant, in a mouse model of intranasal immunization and pulmonary challenge. Robust systemic and mucosal antibody- and T cell-mediated immunities were induced against both proteins, particularly IpaB. Mice immunized in the presence of dmLT with IpaB alone or IpaB combined with IpaD were fully protected against lethal pulmonary infection with Shigella flexneri and Shigella sonnei. We provide the first demonstration that the Shigella TTSAs IpaB and IpaD are promising antigens for the development of a cross-protective Shigella vaccine. PMID:22202122
Simmons, Blake A.; Hill, Vincent R.; Fintschenko, Yolanda; Cummings, Eric B.
2012-09-04
Disclosed is a method for monitoring sources of public water supply for a variety of pathogens by using a combination of ultrafiltration techniques together dielectrophoretic separation techniques. Because water-borne pathogens, whether present due to "natural" contamination or intentional introduction, would likely be present in drinking water at low concentrations when samples are collected for monitoring or outbreak investigations, an approach is needed to quickly and efficiently concentrate and separate particles such as viruses, bacteria, and parasites in large volumes of water (e.g., 100 L or more) while simultaneously reducing the sample volume to levels sufficient for detecting low concentrations of microbes (e.g., <10 mL). The technique is also designed to screen the separated microbes based on specific conductivity and size.
Climate Change Impact Assessment of Food- and Waterborne Diseases.
Semenza, Jan C; Herbst, Susanne; Rechenburg, Andrea; Suk, Jonathan E; Höser, Christoph; Schreiber, Christiane; Kistemann, Thomas
2012-04-01
The PubMed and ScienceDirect bibliographic databases were searched for the period of 1998-2009 to evaluate the impact of climatic and environmental determinants on food- and waterborne diseases. The authors assessed 1,642 short and concise sentences (key facts), which were extracted from 722 relevant articles and stored in a climate change knowledge base. Key facts pertaining to temperature, precipitation, water, and food for 6 selected pathogens were scrutinized, evaluated, and compiled according to exposure pathways. These key facts (corresponding to approximately 50,000 words) were mapped to 275 terminology terms identified in the literature, which generated 6,341 connections. These relationships were plotted on semantic network maps to examine the interconnections between variables. The risk of campylobacteriosis is associated with mean weekly temperatures, although this link is shown more strongly in the literature relating to salmonellosis. Irregular and severe rain events are associated with Cryptosporidium sp. outbreaks, while noncholera Vibrio sp. displays increased growth rates in coastal waters during hot summers. In contrast, for Norovirus and Listeria sp. the association with climatic variables was relatively weak, but much stronger for food determinants. Electronic data mining to assess the impact of climate change on food- and waterborne diseases assured a methodical appraisal of the field. This climate change knowledge base can support national climate change vulnerability, impact, and adaptation assessments and facilitate the management of future threats from infectious diseases. In the light of diminishing resources for public health this approach can help balance different climate change adaptation options.
Climate Change Impact Assessment of Food- and Waterborne Diseases
Semenza, Jan C.; Herbst, Susanne; Rechenburg, Andrea; Suk, Jonathan E.; Höser, Christoph; Schreiber, Christiane; Kistemann, Thomas
2011-01-01
The PubMed and ScienceDirect bibliographic databases were searched for the period of 1998–2009 to evaluate the impact of climatic and environmental determinants on food- and waterborne diseases. The authors assessed 1,642 short and concise sentences (key facts), which were extracted from 722 relevant articles and stored in a climate change knowledge base. Key facts pertaining to temperature, precipitation, water, and food for 6 selected pathogens were scrutinized, evaluated, and compiled according to exposure pathways. These key facts (corresponding to approximately 50,000 words) were mapped to 275 terminology terms identified in the literature, which generated 6,341 connections. These relationships were plotted on semantic network maps to examine the interconnections between variables. The risk of campylobacteriosis is associated with mean weekly temperatures, although this link is shown more strongly in the literature relating to salmonellosis. Irregular and severe rain events are associated with Cryptosporidium sp. outbreaks, while noncholera Vibrio sp. displays increased growth rates in coastal waters during hot summers. In contrast, for Norovirus and Listeria sp. the association with climatic variables was relatively weak, but much stronger for food determinants. Electronic data mining to assess the impact of climate change on food- and waterborne diseases assured a methodical appraisal of the field. This climate change knowledge base can support national climate change vulnerability, impact, and adaptation assessments and facilitate the management of future threats from infectious diseases. In the light of diminishing resources for public health this approach can help balance different climate change adaptation options. PMID:24808720
A Spike Cocktail Approach to Improve Microbial Performance ...
Water reuse, via either centralized treatment of traditional wastewater or decentralized treatment and on-site reuse, is becoming an increasingly important element of sustainable water management. Despite advances in waterborne pathogen detection methods, low and highly variable pathogen levels limit their utility for routine evaluation of health risks in water reuse systems. Therefore, there is a need to improve our understanding of the linkage between pathogens and more readily measured process indicators during treatment. This paper describes an approach for constructing spiking experiments to relate the behavior of viral, bacterial, and protozoan pathogens with relevant process indicators. General issues are reviewed, and the spiking protocol is applied as a case study example to improve microbial performance monitoring and health risk evaluation in a water reuse system. This approach provides a foundation for the development of novel approaches to improve real or near-real time performance monitoring of water recycling systems. This manuscrupt details an approach for developing "spike cocktail", a mixture of microorganisms that can be used to evaluate the performance of engineered and natural systems.
Starting from the bench--prevention and control of foodborne and zoonotic diseases.
Vongkamjan, Kitiya; Wiedmann, Martin
2015-02-01
Foodborne diseases are estimated to cause around 50 million disease cases and 3000 deaths a year in the US. Worldwide, food and waterborne diseases are estimated to cause more than 2 million deaths per year. Lab-based research is a key component of efforts to prevent and control foodborne diseases. Over the last two decades, molecular characterization of pathogen isolates has emerged as a key component of foodborne and zoonotic disease prevention and control. Characterization methods have evolved from banding pattern-based subtyping methods to sequenced-based approaches, including full genome sequencing. Molecular subtyping methods not only play a key role for characterizing pathogen transmission and detection of disease outbreaks, but also allow for identification of clonal pathogen groups that show distinct transmission characteristics. Importantly, the data generated from molecular characterization of foodborne pathogens also represent critical inputs for epidemiological and modeling studies. Continued and enhanced collaborations between infectious disease related laboratory sciences and epidemiologists, modelers, and other quantitative scientists will be critical to a One-Health approach that delivers societal benefits, including improved surveillance systems and prevention approaches for zoonotic and foodborne pathogens. Copyright © 2014 Elsevier B.V. All rights reserved.
Electrochemical Methodologies for the Detection of Pathogens.
Amiri, Mandana; Bezaatpour, Abolfazl; Jafari, Hamed; Boukherroub, Rabah; Szunerits, Sabine
2018-05-25
Bacterial infections remain one of the principal causes of morbidity and mortality worldwide. The number of deaths due to infections is declining every year by only 1% with a forecast of 13 million deaths in 2050. Among the 1400 recognized human pathogens, the majority of infectious diseases is caused by just a few, about 20 pathogens only. While the development of vaccinations and novel antibacterial drugs and treatments are at the forefront of research, and strongly financially supported by policy makers, another manner to limit and control infectious outbreaks is targeting the development and implementation of early warning systems, which indicate qualitatively and quantitatively the presence of a pathogen. As toxin contaminated food and drink are a potential threat to human health and consequently have a significant socioeconomic impact worldwide, the detection of pathogenic bacteria remains not only a big scientific challenge but also a practical problem of enormous significance. Numerous analytical methods, including conventional culturing and staining techniques as well as molecular methods based on polymerase chain reaction amplification and immunological assays, have emerged over the years and are used to identify and quantify pathogenic agents. While being highly sensitive in most cases, these approaches are highly time, labor, and cost consuming, requiring trained personnel to perform the frequently complex assays. A great challenge in this field is therefore to develop rapid, sensitive, specific, and if possible miniaturized devices to validate the presence of pathogens in cost and time efficient manners. Electrochemical sensors are well accepted powerful tools for the detection of disease-related biomarkers and environmental and organic hazards. They have also found widespread interest in the last years for the detection of waterborne and foodborne pathogens due to their label free character and high sensitivity. This Review is focused on the current electrochemical-based microorganism recognition approaches and putting them into context of other sensing devices for pathogens such as culturing the microorganism on agar plates and the polymer chain reaction (PCR) method, able to identify the DNA of the microorganism. Recent breakthroughs will be highlighted, including the utilization of microfluidic devices and immunomagnetic separation for multiple pathogen analysis in a single device. We will conclude with some perspectives and outlooks to better understand shortcomings. Indeed, there is currently no adequate solution that allows the selective and sensitive binding to a specific microorganism, that is fast in detection and screening, cheap to implement, and able to be conceptualized for a wide range of biologically relevant targets.
[Microorganisms surviving in drinking water systems and related problems].
Aulicino, F A; Pastoni, F
2004-01-01
Drinking water in distribution systems may show abnormal values of some parameters, such as turbidity, and may support particular phenomena, such as bacterial regrowth or presence of Viable Not Culturable (VNC) bacteria. Turbidity can provide shelter for opportunistic microorganisms and pathogens. The Milwaukee outbreak (400,000 people) is one example of waterborne disease caused by the presence of pathogens (Cryptosporidium) in drinking water characterized by high and intermittent levels of turbidity. Bacterial regrowth in drinking water distribution systems may cause high increments of microorganisms such as heterotrophic bacteria, coliforms and pathogens. Microorganisms isolated from biofilm including Pseudomonas, Aeromonas, Legionella may have a significant health hazard especially in hospital areas. The presence of VNC bacteria in drinking water may represent a problem for their discussed role in infectious diseases, but also for the possibility of a considerable underestimation of true microbial concentrations in drinking waters. To study this kind of problems is necessary to apply suitable methods for drinking water analyses.
Berjeaud, Jean-Marc; Chevalier, Sylvie; Schlusselhuber, Margot; Portier, Emilie; Loiseau, Clémence; Aucher, Willy; Lesouhaitier, Olivier; Verdon, Julien
2016-01-01
Legionella pneumophila, the major causative agent of Legionnaires’ disease, is found in freshwater environments in close association with free-living amoebae and multispecies biofilms, leading to persistence, spread, biocide resistance, and elevated virulence of the bacterium. Indeed, legionellosis outbreaks are mainly due to the ability of this bacterium to colonize and persist in water facilities, despite harsh physical and chemical treatments. However, these treatments are not totally efficient and, after a lag period, L. pneumophila may be able to quickly re-colonize these systems. Several natural compounds (biosurfactants, antimicrobial peptides…) with anti-Legionella properties have recently been described in the literature, highlighting their specific activities against this pathogen. In this review, we first consider this hallmark of Legionella to resist killing, in regard to its biofilm or host-associated life style. Then, we focus more accurately on natural anti-Legionella molecules described so far, which could provide new eco-friendly and alternative ways to struggle against this important pathogen in plumbing. PMID:27092135
Aderem, Alan; Adkins, Joshua N.; Ansong, Charles; Galagan, James; Kaiser, Shari; Korth, Marcus J.; Law, G. Lynn; McDermott, Jason G.; Proll, Sean C.; Rosenberger, Carrie; Schoolnik, Gary; Katze, Michael G.
2011-01-01
The twentieth century was marked by extraordinary advances in our understanding of microbes and infectious disease, but pandemics remain, food and waterborne illnesses are frequent, multidrug-resistant microbes are on the rise, and the needed drugs and vaccines have not been developed. The scientific approaches of the past—including the intense focus on individual genes and proteins typical of molecular biology—have not been sufficient to address these challenges. The first decade of the twenty-first century has seen remarkable innovations in technology and computational methods. These new tools provide nearly comprehensive views of complex biological systems and can provide a correspondingly deeper understanding of pathogen-host interactions. To take full advantage of these innovations, the National Institute of Allergy and Infectious Diseases recently initiated the Systems Biology Program for Infectious Disease Research. As participants of the Systems Biology Program, we think that the time is at hand to redefine the pathogen-host research paradigm. PMID:21285433
Koedrith, Preeyaporn; Thasiphu, Thalisa; Weon, Jong-Il; Boonprasert, Rattana; Tuitemwong, Kooranee; Tuitemwong, Pravate
2015-01-01
Of global concern, environmental pollution adversely affects human health and socioeconomic development. The presence of environmental contaminants, especially bacterial, viral, and parasitic pathogens and their toxins as well as chemical substances, poses serious public health concerns. Nanoparticle-based biosensors are considered as potential tools for rapid, specific, and highly sensitive detection of the analyte of interest (both biotic and abiotic contaminants). In particular, there are several limitations of conventional detection methods for water-borne pathogens due to low concentrations and interference with various enzymatic inhibitors in the environmental samples. The increase of cells to detection levels requires long incubation time. This review describes current state of biosensor nanotechnology, the advantage over conventional detection methods, and the challenges due to testing of environmental samples. The major approach is to use nanoparticles as signal reporter to increase output rather than spending time to increase cell concentrations. Trends in future development of novel detection devices and their advantages over other environmental monitoring methodologies are also discussed. PMID:25884032
Human infection with bacteria exhibiting mono or multiple antimicrobial resistance (MAR) has been a growing problem in the US, and studies have implicated livestock as a source of MAR bacteria primarily through foodborne transmission routes. However, waterborne transmission of...
Benedict, Katharine M; Reses, Hannah; Vigar, Marissa; Roth, David M; Roberts, Virginia A; Mattioli, Mia; Cooley, Laura A; Hilborn, Elizabeth D; Wade, Timothy J; Fullerton, Kathleen E; Yoder, Jonathan S; Hill, Vincent R
2017-11-10
Provision of safe water in the United States is vital to protecting public health (1). Public health agencies in the U.S. states and territories* report information on waterborne disease outbreaks to CDC through the National Outbreak Reporting System (NORS) (https://www.cdc.gov/healthywater/surveillance/index.html). During 2013-2014, 42 drinking water-associated † outbreaks were reported, accounting for at least 1,006 cases of illness, 124 hospitalizations, and 13 deaths. Legionella was associated with 57% of these outbreaks and all of the deaths. Sixty-nine percent of the reported illnesses occurred in four outbreaks in which the etiology was determined to be either a chemical or toxin or the parasite Cryptosporidium. Drinking water contamination events can cause disruptions in water service, large impacts on public health, and persistent community concern about drinking water quality. Effective water treatment and regulations can protect public drinking water supplies in the United States, and rapid detection, identification of the cause, and response to illness reports can reduce the transmission of infectious pathogens and harmful chemicals and toxins.
Sources and species of cryptosporidium oocysts in the Wachusett Reservoir watershed.
Jellison, Kristen L; Hemond, Harold F; Schauer, David B
2002-02-01
Understanding the behavior of Cryptosporidium oocysts in the environment is critical to developing improved watershed management practices for protection of the public from waterborne cryptosporidiosis. Analytical methods of improved specificity and sensitivity are essential to this task. We developed a nested PCR-restriction fragment length polymorphism assay that allows detection of a single oocyst in environmental samples and differentiates the human pathogen Cryptosporidium parvum from other Cryptosporidium species. We tested our method on surface water and animal fecal samples from the Wachusett Reservoir watershed in central Massachusetts. We also directly compared results from our method with those from the immunofluorescence microscopy assay recommended in the Information Collection Rule. Our results suggest that immunofluorescence microscopy may not be a reliable indicator of public health risk for waterborne cryptosporidiosis. Molecular and environmental data identify both wildlife and dairy farms as sources of oocysts in the watershed, implicate times of cold water temperatures as high-risk periods for oocyst contamination of surface waters, and suggest that not all oocysts in the environment pose a threat to public health.
Microbiological effectiveness of mineral pot filters in Cambodia.
Brown, Joe; Chai, Ratana; Wang, Alice; Sobsey, Mark D
2012-11-06
Mineral pot filters (MPFs) are household water treatment (HWT) devices that are manufactured and distributed by the private sector, with millions of users in Southeast Asia. Their effectiveness in reducing waterborne microbes has not been previously investigated. We purchased three types of MPFs available on the Cambodian market for systematic evaluation of bacteria, virus, and protozoan surrogate microbial reduction in laboratory challenge experiments following WHO recommended performance testing protocols. Results over the total 1500 L testing period per filter indicate that the devices tested were highly effective in reducing Esherichia coli (99.99%+), moderately effective in reducing bacteriophage MS2 (99%+), and somewhat effective against Bacillus atrophaeus, a spore-forming bacterium we used as a surrogate for protozoa (88%+). Treatment mechanisms for all filters included porous ceramic and activated carbon filtration. Our results suggest that these commercially available filters may be at least as effective against waterborne pathogens as other, locally available treatment options such as ceramic pot filters or boiling. More research is needed on the role these devices may play as interim solutions to the problem of unsafe drinking water in Cambodia and globally.
A waterborne norovirus gastroenteritis outbreak in a school, eastern China.
Zhou, N; Zhang, H; Lin, X; Hou, P; Wang, S; Tao, Z; Bi, Z; Xu, A
2016-04-01
In late 2014, a gastroenteritis outbreak occurred in a school in Shandong Province, eastern China. Hundreds of individuals developed the symptoms of diarrhoea and vomiting. Epidemiological investigation showed that food consumption was not linked to this outbreak, and unboiled direct drinking water was identified as the independent risk factor with a relative risk of 1·37 (95% confidence interval 1·03-1·83). Furthermore, examination of common bacterial and viral gastroenteritis pathogens was conducted on different specimens. Norovirus GI.1, GI.2, GI.6, GII.4, GII.6 and GII.13 were detected in clinical specimens and a water sample. GII.4 sequences between clinical specimens and the water sample displayed a close relationship and belonged to GII.4 variant Sydney 2012. These results indicate that direct drinking water contaminated by norovirus was responsible for this gastroenteritis outbreak. This study enriches our knowledge of waterborne norovirus outbreaks in China, and presents valuable prevention and control practices for policy-makers. In future, strengthened surveillance and supervision of direct drinking-water systems is needed.
Comparison of fecal indicators with pathogenic bacteria and rotavirus in groundwater.
Ferguson, Andrew S; Layton, Alice C; Mailloux, Brian J; Culligan, Patricia J; Williams, Daniel E; Smartt, Abby E; Sayler, Gary S; Feighery, John; McKay, Larry D; Knappett, Peter S K; Alexandrova, Ekaterina; Arbit, Talia; Emch, Michael; Escamilla, Veronica; Ahmed, Kazi Matin; Alam, Md Jahangir; Streatfield, P Kim; Yunus, Mohammad; van Geen, Alexander
2012-08-01
Groundwater is routinely analyzed for fecal indicators but direct comparisons of fecal indicators to the presence of bacterial and viral pathogens are rare. This study was conducted in rural Bangladesh where the human population density is high, sanitation is poor, and groundwater pumped from shallow tubewells is often contaminated with fecal bacteria. Five indicator microorganisms (E. coli, total coliform, F+RNA coliphage, Bacteroides and human-associated Bacteroides) and various environmental parameters were compared to the direct detection of waterborne pathogens by quantitative PCR in groundwater pumped from 50 tubewells. Rotavirus was detected in groundwater filtrate from the largest proportion of tubewells (40%), followed by Shigella (10%), Vibrio (10%), and pathogenic E. coli (8%). Spearman rank correlations and sensitivity-specificity calculations indicate that some, but not all, combinations of indicators and environmental parameters can predict the presence of pathogens. Culture-dependent fecal indicator bacteria measured on a single date did not predict total bacterial pathogens, but annually averaged monthly measurements of culturable E. coli did improve prediction for total bacterial pathogens. A qPCR-based E. coli assay was the best indicator for the bacterial pathogens. F+RNA coliphage were neither correlated nor sufficiently sensitive towards rotavirus, but were predictive of bacterial pathogens. Since groundwater cannot be excluded as a significant source of diarrheal disease in Bangladesh and neighboring countries with similar characteristics, the need to develop more effective methods for screening tubewells with respect to microbial contamination is necessary. Copyright © 2012 Elsevier B.V. All rights reserved.
Comparison of fecal indicators with pathogenic bacteria and rotavirus in groundwater
Ferguson, Andrew S.; Layton, Alice C.; Mailloux, Brian J; Culligan, Patricia J.; Williams, Daniel E.; Smartt, Abby E.; Sayler, Gary S.; Feighery, John; McKay, Larry; Knappett, Peter S.K.; Alexandrova, Ekaterina; Arbit, Talia; Emch, Michael; Escamilla, Veronica; Ahmed, Kazi Matin; Alam, Md. Jahangir; Streatfield, P. Kim; Yunus, Mohammad; van Geen, Alexander
2012-01-01
Groundwater is routinely analyzed for fecal indicators but direct comparisons of fecal indicators to the presence of bacterial and viral pathogens are rare. This study was conducted in rural Bangladesh where the human population density is high, sanitation is poor, and groundwater pumped from shallow tubewells is often contaminated with fecal bacteria. Five indicator microorganisms (E. coli, total coliform, F+RNA coliphage, Bacteroides and human-associated Bacteroides) and various environmental parameters were compared to the direct detection of waterborne pathogens by quantitative PCR in groundwater pumped from 50 tubewells. Rotavirus was detected in groundwater filtrate from the largest proportion of tubewells (40%), followed by Shigella (10%), Vibrio (10%), and pathogenic E. coli (8%). Spearman rank correlations and sensitivity-specificity calculations indicate that some, but not all, combinations of indicators and environmental parameters can predict the presence of pathogens. Culture-dependent fecal indicator bacteria measured on a single date did not predict total bacterial pathogens, but annually averaged monthly measurements of culturable E. coli did improve prediction for total bacterial pathogens. A qPCR-based E. coli assay was the best indicator for the bacterial pathogens. F+RNA coliphage were neither correlated nor sufficiently sensitive towards rotavirus, but were predictive of bacterial pathogens. Since groundwater cannot be excluded as a significant source of diarrheal disease in Bangladesh and neighboring countries with similar characteristics, the need to develop more effective methods for screening tubewells with respect to microbial contamination is necessary. PMID:22705866
Tropical environments, human activities, and the transmission of infectious diseases.
Sattenspiel, L
2000-01-01
Throughout recent history, the tropical regions of the world have been affected more severely by infectious diseases than the temperate world. Much of the success of infectious diseases in that region is due to both biological and environmental factors that encourage high levels of biodiversity in hosts, vectors, and pathogens, and social factors that compromise efforts to control diseases. Several of these factors are described. Discussion then shifts to specific types of host-pathogen relationships. The most important of these in the tropics is the relationship between humans, a pathogen, and a vector that carries the pathogen from one human to another. Mosquitoes are the vector responsible for the transmission of many vector-borne human diseases. Characteristics of mosquito-human interactions are described, including cultural behaviors humans have developed that both increase the chances of transmission and help to limit that transmission. The transmission of water-borne diseases, fecal-oral transmission, zoonotic diseases, respiratory illnesses, and sexually transmitted diseases are also discussed. Attention is paid to how diseases with these modes of transmission differ in characteristics and importance in tropical human populations compared to those in temperate regions. Following this general discussion, three case studies are presented in some detail. The diseases chosen for the case studies include cholera, lymphatic filariasis, and dracunculiasis (guinea worm). These three case studies taken together provide examples of the diversity of human host-pathogen interactions as well as ways that human activities have both promoted their spread and helped to control them. The transmission of all three diseases is related to the nature and quality of water sources. The transmission of cholera, a water-borne disease, is related to sanitation practices, physical characteristics of the environment such as temperature and humidity, and modern shipping practices. Lymphatic filariasis, a mosquito-borne disease, has increased in frequency in parts of Africa in recent decades as a consequence of large-scale agricultural development projects that have shifted the nature and quantity of water sources and potential mosquito breeding sites. Dracunculiasis is transmitted by a small crustacean that contaminates sources of drinking water. Because its transmission can be prevented by a simple change in human behavior, filtering all water with a small piece of cloth before using it, dracunculiasis has been the focus of a major eradication effort that is near success.
Ashbolt, Nicholas J.
2015-01-01
Major waterborne (enteric) pathogens are relatively well understood and treatment controls are effective when well managed. However, water-based, saprozoic pathogens that grow within engineered water systems (primarily within biofilms/sediments) cannot be controlled by water treatment alone prior to entry into water distribution and other engineered water systems. Growth within biofilms or as in the case of Legionella pneumophila, primarily within free-living protozoa feeding on biofilms, results from competitive advantage. Meaning, to understand how to manage water-based pathogen diseases (a sub-set of saprozoses) we need to understand the microbial ecology of biofilms; with key factors including biofilm bacterial diversity that influence amoebae hosts and members antagonistic to water-based pathogens, along with impacts from biofilm substratum, water temperature, flow conditions and disinfectant residual—all control variables. Major saprozoic pathogens covering viruses, bacteria, fungi and free-living protozoa are listed, yet today most of the recognized health burden from drinking waters is driven by legionellae, non-tuberculous mycobacteria (NTM) and, to a lesser extent, Pseudomonas aeruginosa. In developing best management practices for engineered water systems based on hazard analysis critical control point (HACCP) or water safety plan (WSP) approaches, multi-factor control strategies, based on quantitative microbial risk assessments need to be developed, to reduce disease from largely opportunistic, water-based pathogens. PMID:26102291
Transport and fate of microbial pathogens in agricultural settings
Bradford, Scott A.; Morales, Veronica L.; Zhang, Wei; Harvey, Ronald W.; Packman, Aaron I.; Mohanram, Arvind; Welty, Claire
2013-01-01
An understanding of the transport and survival of microbial pathogens (pathogens hereafter) in agricultural settings is needed to assess the risk of pathogen contamination to water and food resources, and to develop control strategies and treatment options. However, many knowledge gaps still remain in predicting the fate and transport of pathogens in runoff water, and then through the shallow vadose zone and groundwater. A number of transport pathways, processes, factors, and mathematical models often are needed to describe pathogen fate in agricultural settings. The level of complexity is dramatically enhanced by soil heterogeneity, as well as by temporal variability in temperature, water inputs, and pathogen sources. There is substantial variability in pathogen migration pathways, leading to changes in the dominant processes that control pathogen transport over different spatial and temporal scales. For example, intense rainfall events can generate runoff and preferential flow that can rapidly transport pathogens. Pathogens that survive for extended periods of time have a greatly enhanced probability of remaining viable when subjected to such rapid-transport events. Conversely, in dry seasons, pathogen transport depends more strongly on retention at diverse environmental surfaces controlled by a multitude of coupled physical, chemical, and microbiological factors. These interactions are incompletely characterized, leading to a lack of consensus on the proper mathematical framework to model pathogen transport even at the column scale. In addition, little is known about how to quantify transport and survival parameters at the scale of agricultural fields or watersheds. This review summarizes current conceptual and quantitative models for pathogen transport and fate in agricultural settings over a wide range of spatial and temporal scales. The authors also discuss the benefits that can be realized by improved modeling, and potential treatments to mitigate the risk of waterborne disease transmission.
Comparative isolation and genetic diversity of Arcobacter sp. from fish and the coastal environment.
Rathlavath, S; Kumar, S; Nayak, B B
2017-07-01
Arcobacter species are emerging food-borne and water-borne human pathogens associated mostly with food animals and their environment. The present study was aimed to isolate Arcobacter species from fish, shellfish and coastal water samples using two methods and to determine their genetic diversity. Of 201 samples of fish, shellfish and water samples analysed, 66 (32·8%) samples showed the presence of Arcobacter DNA from both Arcobacter enrichment broth and Bolton broth. Arcobacters were isolated from 58 (87·8%) and 38 (57·5%) of Arcobacter DNA-positive samples using Arcobacter blood agar and Preston blood agar, respectively. Arcobacter sp. identified by biochemical tests were further analysed by a genus-specific PCR, followed by a multiplex-PCR and 16S rRNA-RFLP. From both the methods, four different Arcobacter species namely Arcobacter butzleri, Arcobacter skirrowii, Arcobacter mytili and Arcobacter defluvii were isolated, of which A. butzleri was the predominant species. Enterobacterial repetitive intergenic consensus (ERIC)-PCR fingerprint analysis revealed that the arcobacters isolated in this study were genetically very diverse and no specific genotype was found associated with a specific source (seafood or water). Since pathogenic arcobacters are not known to be natural inhabitants of coastal marine environment, identifying the sources of contamination will be crucial for effective management of this problem. Arcobacter sp. are emerging food- and water-borne human pathogens. In this study, comparison of two selective media suggested Arcobacter blood agar to be more efficient in yielding Arcobacter sp. from seafood. Furthermore, the isolation of Arcobacter sp. such as Arcobacter butzleri, A. skirrowii, A. mytili and A. defluvii from seafood suggests diverse sources of contamination of seafood by Arcobacter sp. Analysis of enterobacterial repetitive intergenic consensus sequence-PCR patterns of A. butzleri showed high genetic diversity and lack of clonality among the isolates. Arcobacter contamination of seafood is an emerging issue both from seafood safety and seafood trade point of view. © 2017 The Society for Applied Microbiology.
NASA Astrophysics Data System (ADS)
Kusiluka, L. J. M.; Karimuribo, E. D.; Mdegela, R. H.; Luoga, E. J.; Munishi, P. K. T.; Mlozi, M. R. S.; Kambarage, D. M.
A study on the prevalence of water-borne zoonotic pathogens in water, cattle and humans was conducted in six villages in Dodoma Rural (5) and Bagamoyo (1) districts, Tanzania. Water sources were screened for faecal coliform organisms, thermophilic Campylobacter, Salmonella, Cryptosporidium and Giardia. Faecal samples from cattle and humans were also analysed for the above specific pathogens. Results indicate that 70.8% ( n = 48) of the water sources screened were contaminated with faecal coliform organisms. Water sources in two villages, one each in Dodoma Rural and Bagamoyo districts were also contaminated with Giardia lamblia. The overall prevalence of Campylobacter jejuni in cattle in the two study areas was 2.3% ( n = 942) and at least one animal in each village was infected with C. jejuni. Cryptosporidium parvum was detected in 0.5% ( n = 942) of the cattle examined in three villages in Dodoma district. Salmonella spp. was demonstrated in only 1.4% ( n = 144) of the cattle in Chalinze village in Dodoma Rural district while G. lamblia was only detected in 1.5% ( n = 202) of the animals examined in Chamakweza village in Bagamoyo district. Nine (1.9%) of the people screened at three heath centres in the study areas were infected with C. jejuni while 3.7% ( n = 484) of the people had C. parvum oocysts. G. lamblia was detected in 2.5% of the 202 people screened at the Chalinze health centre in Bagamoyo district. Analysis of the secondary data revealed that clinical complaints related to enteric diseases were prevalent in humans in the two areas throughout the year and the prevalence varied from about 1% to 25% in both <5 years and ⩾5 years patients. In conclusion, this study has highlighted the possible public health risks, which may be associated with keeping of animals and sharing of water sources between humans and animals.
Mazzillo, Fernanda F. M.; Shapiro, Karen; Silver, Mary W.
2013-01-01
Toxoplasma gondii is a land-derived parasite that infects humans and marine mammals. Infections are a significant cause of mortality for endangered southern sea otters (Enhydra lutris nereis), but the transmission mechanism is poorly understood. Otter exposure to T. gondii has been linked to the consumption of marine turban snails in kelp (Macrocystis pyrifera) forests. It is unknown how turban snails acquire oocysts, as snails scrape food particles attached to surfaces, whereas T. gondii oocysts enter kelp beds as suspended particles via runoff. We hypothesized that waterborne T. gondii oocysts attach to kelp surfaces when encountering exopolymer substances (EPS) forming the sticky matrix of biofilms on kelp, and thus become available to snails. Results of a dietary composition analysis of field-collected snails and of kelp biofilm indicate that snails graze the dense kelp-biofilm assemblage composed of pennate diatoms and bacteria inserted within the EPS gel-like matrix. To test whether oocysts attach to kelp blades via EPS, we designed a laboratory experiment simulating the kelp forest canopy in tanks spiked with T. gondii surrogate microspheres and controlled for EPS and transparent exopolymer particles (TEP - the particulate form of EPS). On average, 19% and 31% of surrogates were detected attached to kelp surfaces covered with EPS in unfiltered and filtered seawater treatments, respectively. The presence of TEP in the seawater did not increase surrogate attachment. These findings support a novel transport mechanism of T. gondii oocysts: as oocysts enter the kelp forest canopy, a portion adheres to the sticky kelp biofilms. Snails grazing this biofilm encounter oocysts as ‘bycatch’ and thereby deliver the parasite to sea otters that prey upon snails. This novel mechanism can have health implications beyond T. gondii and otters, as a similar route of pathogen transmission may be implicated with other waterborne pathogens to marine wildlife and humans consuming biofilm-feeding invertebrates. PMID:24386100
Zahedi, Alireza; Paparini, Andrea; Jian, Fuchun; Robertson, Ian; Ryan, Una
2016-04-01
Cryptosporidium is an enteric parasite that is transmitted via the faecal-oral route, water and food. Humans, wildlife and domestic livestock all potentially contribute Cryptosporidium to surface waters. Human encroachment into natural ecosystems has led to an increase in interactions between humans, domestic animals and wildlife populations. Increasing numbers of zoonotic diseases and spill over/back of zoonotic pathogens is a consequence of this anthropogenic disturbance. Drinking water catchments and water reservoir areas have been at the front line of this conflict as they can be easily contaminated by zoonotic waterborne pathogens. Therefore, the epidemiology of zoonotic species of Cryptosporidium in free-ranging and captive wildlife is of increasing importance. This review focuses on zoonotic Cryptosporidium species reported in global wildlife populations to date, and highlights their significance for public health and the water industry.
Bissonnette, Luc; Maheux, Andrée F; Bergeron, Michel G
2017-01-01
The microbial assessment of potable/drinking water is done to ensure that the resource is free of fecal contamination indicators or waterborne pathogens. Culture-based methods for verifying the microbial safety are limited in the sense that a standard volume of water is generally tested for only one indicator (family) or pathogen.In this work, we describe a membrane filtration-based molecular microbiology method, CRENAME (Concentration Recovery Extraction of Nucleic Acids and Molecular Enrichment), exploiting molecular enrichment by whole genome amplification (WGA) to yield, in less than 4 h, a nucleic acid preparation which can be repetitively tested by real-time PCR for example, to provide multiparametric presence/absence tests (1 colony forming unit or microbial particle per standard volume of 100-1000 mL) for bacterial or protozoan parasite cells or particles susceptible to contaminate potable/drinking water.
Zhang, Chi; Li, Yi; Shuai, Danmeng; Zhang, Wenlong; Niu, Lihua; Wang, Longfei; Zhang, Huanjun
2018-05-28
Waterborne pathogens, especially bacteria and viruses, pose significant health risks to the public, calling for the development of a sustainable, efficient, and robust disinfection strategy with reduced energy footprint and minimized byproduct formation. Here, we developed a sustainable photocatalytic composite for antimicrobial applications by integrating visible-light-responsive graphitic carbon nitride (g-C 3 N 4 ) with low-density porous expanded perlite (EP) mineral, and g-C 3 N 4 /EP-520 showed a high specific surface area of 45.3 m 2 /g and optimum performance for disinfection. g-C 3 N 4 /EP-520 achieved 8-log inactivation of E. coli and MS2 under 180 and 240 min visible-light irradiation without stirring, respectively. Water quality parameters were found to influence the disinfection performance of g-C 3 N 4 /EP-520: MS2 inactivation was promoted with the increase of dissolved oxygen (DO), proton concentration, salinity (NaCl), and hardness (Ca 2+ ). Importantly, g-C 3 N 4 /EP-520 could fully inactivate MS2 in a real source water sample with prolonged light irradiation, and negligible activity loss was observed in recycle use, demonstrating its viability and robustness for waterborne pathogen removal. Antimicrobial mechanisms of g-C 3 N 4 /EP-520 were systemically evaluated by radical scavenger addition, and revealed that the inactivation behavior was dependent on the type of microorganisms. Microscopic analyses confirmed that the destruction of bacterial cells and viral particles, leading to the inactivation of microorganisms. Copyright © 2018 Elsevier Ltd. All rights reserved.
Health Risk Assessment Related to Waterborne Pathogens from the River to the Tap
Jacob, Pauline; Henry, Annabelle; Meheut, Gaëlle; Charni-Ben-Tabassi, Nadine; Ingrand, Valérie; Helmi, Karim
2015-01-01
A two-year monitoring program of Cryptosporidium parvum oocysts, Giardia duodenalis cysts, Escherichia coli, Clostridium perfringens spores and adenovirus was conducted in three large rivers in France used for recreational activities and as a resource for drinking water production. Fifty-liter river water and one thousand-liter tap water samples were concentrated using hollow-fiber ultrafiltration and analyzed by molecular biology or laser-scanning cytometry. In order to evaluate watershed land use influence on microorganism concentration changes, occurrence and seasonality of microorganisms were studied. The highest concentrations of protozoan parasites and C. perfringens were found for one of the three sites, showing a high proportion of agricultural territories, forests and semi-natural environments, which may be partly attributable to soil leaching due to rainfall events. On the contrary, the highest concentrations of adenoviruses were found at the two other sites, probably due to strong urban activities. Health risk assessment was evaluated for each waterborne pathogen regarding exposure during recreational activities (for a single or five bathing events during the summer). The calculated risk was lower than 0.5% for parasites and varied from 1% to 42% for adenovirus. A theoretical assessment of microorganism removal during the drinking water treatment process was also performed, and it showed that an absence of microorganisms could be expected in finished drinking water. This hypothesis was confirmed since all tested tap water samples were negative for each studied microorganism, resulting in a risk for drinking water consumption lower than 0.01% for parasites and lower than 0.5% for adenovirus. PMID:25764059
Ahmad, Farhan; Stedtfeld, Robert D.; Waseem, Hassan; Williams, Maggie R.; Cupples, Alison M.; Tiedje, James M.; Hashsham, Syed A.
2016-01-01
We are reporting a most probable number approach integrated to loop mediated isothermal technique (MPN-LAMP) focusing on Gram-negative Escherichia coli and Gram-positive Enterococcus faecalis bacterial cells without nucleic acids extraction. LAMP assays for uidA from E. coli and gelE from E. faecalis were successfully performed directly on cells up to single digit concentration using a commercial real time PCR instrument. Threshold time values of LAMP assays of bacterial cells, heat treated bacterial cells (95 °C for 5 min), and their purified genomic DNA templates were similar, implying that amplification could be achieved directly from bacterial cells at 63 °C. Viability of bacterial cells was confirmed by using propidium monoazide in a LAMP assay with E. faecalis. To check its functionality on a microfluidic platform, MPN-LAMP assays targeting < 10 CFU of bacteria were also translated onto polymeric microchips and monitored by a low-cost fluorescence imaging system. The overall system provided signal-to-noise (SNR) ratios up to 800, analytical sensitivity of < 10 CFU, and time to positivity of about 20 min. MPN-LAMP assays were performed for cell concentrations in the range of 105 CFU to < 10 CFU. MPN values from LAMP assays confirmed that the amplifications were from < 10 CFU. The method described here, applicable directly on cells at 63 °C, eliminates the requirement of complex nucleic acids extraction steps, facilitating the development of sensitive, rapid, low-cost, and field-deployable systems. This rapid MPN-LAMP approach has the potential to replace conventional MPN method for waterborne pathogens. PMID:27856278
Thickman, Jake D.
2017-01-01
Food safety is a major concern in the shellfish industry, as severe illness can result from consuming shellfish that have accumulated waterborne pathogens. Shellfish harvesting areas are typically monitored for indicator bacteria such as fecal coliforms that serve as proxies for enteric pathogens although these indicators have shown little relation to some naturally occurring pathogenic bacteria such as Vibrio parahaemolyticus. To examine the dynamics and ecology of pathogenic and non-pathogenic strains of V. parahaemolyticus and address the relevance of indicator bacteria in predicting V. parahaemolyticus concentrations, field surveys and experiments were carried out in western Long Island Sound, NY, USA, a region that has experienced recent outbreaks of shellfish contaminated with V. parahaemolyticus. Pathogenic and non-pathogenic strains were quantified via PCR detection of marker genes and most probable number techniques. Field survey data showed little correspondence between fecal coliforms and V. parahaemolyticus, but significant correlations between V. parahaemolyticus and an alternative indicator, enterococci, and between V. parahaemolyticus and short-term (48 h) rainfall were observed. Experiments demonstrated that enrichment of seawater with phytoplankton-derived dissolved organic matter significantly increased the concentration of total V. parahaemolyticus and the presence pathogenic V. parahaemolyticus, but higher temperatures did not. Collectively, these study results suggest that fecal coliforms may fail to account for the full suite of important shellfish pathogens but that enterococci could provide a potential alternative or supplement to shellfish sanitation monitoring. Given the ability of algal-derived dissolved organic matter to promote the growth of pathogenic V. parahaemolyticus, restricting nutrient inputs into coastal water bodies that promote algal blooms may indirectly decrease the proliferation of V. parahaemolyticus and protect public health. PMID:29020074
Thickman, Jake D; Gobler, Christopher J
2017-01-01
Food safety is a major concern in the shellfish industry, as severe illness can result from consuming shellfish that have accumulated waterborne pathogens. Shellfish harvesting areas are typically monitored for indicator bacteria such as fecal coliforms that serve as proxies for enteric pathogens although these indicators have shown little relation to some naturally occurring pathogenic bacteria such as Vibrio parahaemolyticus. To examine the dynamics and ecology of pathogenic and non-pathogenic strains of V. parahaemolyticus and address the relevance of indicator bacteria in predicting V. parahaemolyticus concentrations, field surveys and experiments were carried out in western Long Island Sound, NY, USA, a region that has experienced recent outbreaks of shellfish contaminated with V. parahaemolyticus. Pathogenic and non-pathogenic strains were quantified via PCR detection of marker genes and most probable number techniques. Field survey data showed little correspondence between fecal coliforms and V. parahaemolyticus, but significant correlations between V. parahaemolyticus and an alternative indicator, enterococci, and between V. parahaemolyticus and short-term (48 h) rainfall were observed. Experiments demonstrated that enrichment of seawater with phytoplankton-derived dissolved organic matter significantly increased the concentration of total V. parahaemolyticus and the presence pathogenic V. parahaemolyticus, but higher temperatures did not. Collectively, these study results suggest that fecal coliforms may fail to account for the full suite of important shellfish pathogens but that enterococci could provide a potential alternative or supplement to shellfish sanitation monitoring. Given the ability of algal-derived dissolved organic matter to promote the growth of pathogenic V. parahaemolyticus, restricting nutrient inputs into coastal water bodies that promote algal blooms may indirectly decrease the proliferation of V. parahaemolyticus and protect public health.
Burnet, Jean-Baptiste; Ogorzaly, Leslie; Penny, Christian; Cauchie, Henry-Michel
2015-09-23
The occurrence of faecal pathogens in drinking water resources constitutes a threat to the supply of safe drinking water, even in industrialized nations. To efficiently assess and monitor the risk posed by these pathogens, sampling deserves careful design, based on preliminary knowledge on their distribution dynamics in water. For the protozoan pathogens Cryptosporidium and Giardia, only little is known about their spatial distribution within drinking water supplies, especially at fine scale. Two-dimensional distribution maps were generated by sampling cross-sections at meter resolution in two different zones of a drinking water reservoir. Samples were analysed for protozoan pathogens as well as for E. coli, turbidity and physico-chemical parameters. Parasites displayed heterogeneous distribution patterns, as reflected by significant (oo)cyst density gradients along reservoir depth. Spatial correlations between parasites and E. coli were observed near the reservoir inlet but were absent in the downstream lacustrine zone. Measurements of surface and subsurface flow velocities suggest a role of local hydrodynamics on these spatial patterns. This fine-scale spatial study emphasizes the importance of sampling design (site, depth and position on the reservoir) for the acquisition of representative parasite data and for optimization of microbial risk assessment and monitoring. Such spatial information should prove useful to the modelling of pathogen transport dynamics in drinking water supplies.
Analysis of bacterial metagenomes from the Southwestern Gulf of Mexico for pathogens detection.
Escobedo-Hinojosa, Wendy; Pardo-López, Liliana
2017-07-31
Little is known about the diversity of bacteria in the Southwestern Gulf of Mexico. The aim of the study illustrated in this perspective was to search for the presence of bacterial pathogens in this ecosystem, using metagenomic data recently generated by the Mexican research group known as the Gulf of Mexico Research Consortium. Several genera of bacteria annotated as pathogens were detected in water and sediment marine samples. As expected, native and ubiquitous pathogenic bacteria genera such as Burkolderia, Halomonas, Pseudomonas, Shewanella and Vibrio were highly represented. Surprisingly, non-native genera of public health concern were also detected, including Borrelia, Ehrlichia, Leptospira, Mycobacterium, Mycoplasma, Salmonella, Staphylococcus, Streptococcus and Treponema. While there are no previous metagenomics studies of this environment, the potential influences of natural, anthropogenic and ecological factors on the diversity of putative pathogenic bacteria found in it are reviewed. The taxonomic annotation herein reported provides a starting point for an improved understanding of bacterial biodiversity in the Southwestern Gulf of Mexico. It also represents a useful tool in public health as it may help identify infectious diseases associated with exposure to marine water and ingestion of fish or shellfish, and thus may be useful in predicting and preventing waterborne disease outbreaks. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
DOT National Transportation Integrated Search
1997-10-01
In order to provide waterborne commerce information as soon as possible, the Waterborne Commerce Statistics Center (WCSC) has prepared this summary document of estimated waterborne commerce statistics for calendar year 1996. The foreign import and ex...
DOT National Transportation Integrated Search
1999-07-30
In order to provide waterborne commerce information as soon as possible, the Waterborne Commerce Statistics Center(WCSC) has prepared this summary document of estimated waterborne commerce statistics for calendar year 1998. The foreign import and exp...
Despite advancements in water management and sanitation, waterborne disease outbreaks continue to occur in the United States. CDC collects data on waterborne disease outbreaks submitted from all states and territories* through the Waterborne Disease and Outbreak Surveillance Syst...
Kanungo, Reba; Shashikala; Karunasagar, I; Srinivasan, S; Sheela, Devi; Venkatesh, K; Anitha, P
2007-12-01
Potentially pathogenic members of the Vibrionaceae family including Vibrio cholerae and Vibrio parahemolyticus were isolated from domestic sources of drinking water in coastal villages following sea water inundation during the tsunami in Southern India. Phenotypic and genotypic studies were done to confirm the identity and detection of toxins. Vibrio-gyr (gyrase B gene) was detected in all sixteen vibrio isolates. Toxin regulating genes i.e.: ctx gene, tdh gene, and trh gene, however were not detected in any of the strains, thereby ruling out presence of toxins which could endanger human life. Other potentially pathogenic bacteria Aeromonas and Plesiomonas were also isolated from hand pumps and wells, in a few localities. There was no immediate danger in the form of an outbreak or sporadic gastroenteritis at the time of the study. Timely chlorination and restoration of potable water supply to the flood affected population by governmental and nongovernmental agencies averted waterborne gastroenteritis. Assessment of quality of water and detection of potential virulent organisms is an important public health activity following natural disasters. This work highlights the importance of screening water sources for potentially pathogenic microorganisms after natural disasters to avert outbreaks of gastroenteritis and other infectious diseases.
Hogan, Jennifer N.; Daniels, Miles E.; Watson, Fred G.; Oates, Stori C.; Miller, Melissa A.; Conrad, Patricia A.; Shapiro, Karen; Hardin, Dane; Dominik, Clare; Melli, Ann; Jessup, David A.
2013-01-01
Constructed wetland systems are used to reduce pollutants and pathogens in wastewater effluent, but comparatively little is known about pathogen transport through natural wetland habitats. Fecal protozoans, including Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii, are waterborne pathogens of humans and animals, which are carried by surface waters from land-based sources into coastal waters. This study evaluated key factors of coastal wetlands for the reduction of protozoal parasites in surface waters using settling column and recirculating mesocosm tank experiments. Settling column experiments evaluated the effects of salinity, temperature, and water type (“pure” versus “environmental”) on the vertical settling velocities of C. parvum, G. lamblia, and T. gondii surrogates, with salinity and water type found to significantly affect settling of the parasites. The mesocosm tank experiments evaluated the effects of salinity, flow rate, and vegetation parameters on parasite and surrogate counts, with increased salinity and the presence of vegetation found to be significant factors for removal of parasites in a unidirectional transport wetland system. Overall, this study highlights the importance of water type, salinity, and vegetation parameters for pathogen transport within wetland systems, with implications for wetland management, restoration efforts, and coastal water quality. PMID:23315738
Fault tree analysis of the causes of waterborne outbreaks.
Risebro, Helen L; Doria, Miguel F; Andersson, Yvonne; Medema, Gertjan; Osborn, Keith; Schlosser, Olivier; Hunter, Paul R
2007-01-01
Prevention and containment of outbreaks requires examination of the contribution and interrelation of outbreak causative events. An outbreak fault tree was developed and applied to 61 enteric outbreaks related to public drinking water supplies in the EU. A mean of 3.25 causative events per outbreak were identified; each event was assigned a score based on percentage contribution per outbreak. Source and treatment system causative events often occurred concurrently (in 34 outbreaks). Distribution system causative events occurred less frequently (19 outbreaks) but were often solitary events contributing heavily towards the outbreak (a mean % score of 87.42). Livestock and rainfall in the catchment with no/inadequate filtration of water sources contributed concurrently to 11 of 31 Cryptosporidium outbreaks. Of the 23 protozoan outbreaks experiencing at least one treatment causative event, 90% of these events were filtration deficiencies; by contrast, for bacterial, viral, gastroenteritis and mixed pathogen outbreaks, 75% of treatment events were disinfection deficiencies. Roughly equal numbers of groundwater and surface water outbreaks experienced at least one treatment causative event (18 and 17 outbreaks, respectively). Retrospective analysis of multiple outbreaks of enteric disease can be used to inform outbreak investigations, facilitate corrective measures, and further develop multi-barrier approaches.
Advances in water management and sanitation have reduced waterborne disease in the United States, although outbreaks continue to occur. Public health agencies in the U.S. states and territories* report information on waterborne disease outbreaks to the CDC Waterborne Disease and ...
Water filtration using plant xylem.
Boutilier, Michael S H; Lee, Jongho; Chambers, Valerie; Venkatesh, Varsha; Karnik, Rohit
2014-01-01
Effective point-of-use devices for providing safe drinking water are urgently needed to reduce the global burden of waterborne disease. Here we show that plant xylem from the sapwood of coniferous trees--a readily available, inexpensive, biodegradable, and disposable material--can remove bacteria from water by simple pressure-driven filtration. Approximately 3 cm(3) of sapwood can filter water at the rate of several liters per day, sufficient to meet the clean drinking water needs of one person. The results demonstrate the potential of plant xylem to address the need for pathogen-free drinking water in developing countries and resource-limited settings.
An overview of the domestication and impact of the Salmonella mobilome.
Mebrhatu, Mehari Tesfazgi; Cenens, William; Aertsen, Abram
2014-02-01
Salmonella spp. are accountable for a large fraction of the global infectious disease burden, with most of their infections being food- or water-borne. The phenotypic features and adaptive potential of Salmonella spp. appear to be driven to a large extent by mobile or laterally acquired genetic elements. A better understanding of the conduct and diversification of these important pathogens consequently requires a more profound insight into the different mechanisms by which these pivotal elements establish themselves in the cell and affect its behavior. This review, therefore, provides an overview of the physiological impact and domestication of the Salmonella mobilome.
Effects of wastewater disinfection on waterborne bacteria and viruses
Blatchley, E. R.; Gong, W.-L.; Alleman, J.E.; Rose, J.B.; Huffman, D.E.; Otaki, M.; Lisle, J.T.
2007-01-01
Wastewater disinfection is practiced with the goal of reducing risks of human exposure to pathogenic microorganisms. In most circumstances, the efficacy of a wastewater disinfection process is regulated and monitored based on measurements of the responses of indicator bacteria. However, inactivation of indicator bacteria does not guarantee an acceptable degree of inactivation among other waterborne microorganisms (e.g., microbial pathogens). Undisinfected effluent samples from several municipal wastewater treatment facilities were collected for analysis. Facilities were selected to provide a broad spectrum of effluent quality, particularly as related to nitrogenous compounds. Samples were subjected to bench-scale chlorination and dechlorination and UV irradiation under conditions that allowed compliance with relevant discharge regulations and such that disinfectant exposures could be accurately quantified. Disinfected samples were subjected to a battery of assays to assess the immediate and long-term effects of wastewater disinfection on waterborne bacteria and viruses. In general, (viable) bacterial populations showed an immediate decline as a result of disinfectant exposure; however, incubation of disinfected samples under conditions that were designed to mimic the conditions in a receiving stream resulted in substantial recovery of the total bacterial community. The bacterial groups that are commonly used as indicators do not provide an accurate representation of the response of the bacterial community to disinfectant exposure and subsequent recovery in the environment. UV irradiation and chlorination/dechlorination both accomplished measurable inactivation of indigenous phage; however, the extent of inactivation was fairly modest under the conditions of disinfection used in this study. UV irradiation was consistently more effective as a virucide than chlorination/dechlorination under the conditions of application, based on measurements of virus (phage) diversity and concentration. Taken together, and when considered in conjunction with previously published research, the results of these experiments illustrate several important limitations of common disinfection processes as applied in the treatment of municipal wastewaters. In general, it is not clear that conventional disinfection processes, as commonly implemented, are effective for control of the risks of disease transmission, particularly those associated with viral pathogens. Microbial quality in receiving streams may not be substantially improved by the application of these disinfection processes; under some circumstances, an argument can be made that disinfection may actually yield a decrease in effluent and receiving water quality. Decisions regarding the need for effluent disinfection must account for site-specific characteristics, but it is not clear that disinfection of municipal wastewater effluents is necessary or beneficial for all facilities. When direct human contact or ingestion of municipal wastewater effluents is likely, disinfection may be necessary. Under these circumstances, UV irradiation appears to be superior to chlorination in terms of microbial quality and chemistry and toxicology. This advantage is particularly evident in effluents that contain appreciable quantities of ammonia-nitrogen or organic nitrogen.
Removal of MS2, Qβ and GA bacteriophages during drinking water treatment at pilot scale.
Boudaud, Nicolas; Machinal, Claire; David, Fabienne; Fréval-Le Bourdonnec, Armelle; Jossent, Jérôme; Bakanga, Fanny; Arnal, Charlotte; Jaffrezic, Marie Pierre; Oberti, Sandrine; Gantzer, Christophe
2012-05-15
The removal of MS2, Qβ and GA, F-specific RNA bacteriophages, potential surrogates for pathogenic waterborne viruses, was investigated during a conventional drinking water treatment at pilot scale by using river water, artificially and independently spiked with these bacteriophages. The objective of this work is to develop a standard system for assessing the effectiveness of drinking water plants with respect to the removal of MS2, Qβ and GA bacteriophages by a conventional pre-treatment process (coagulation-flocculation-settling-sand filtration) followed or not by an ultrafiltration (UF) membrane (complete treatment process). The specific performances of three UF membranes alone were assessed by using (i) pre-treated water and (ii) 0.1 mM sterile phosphate buffer solution (PBS), spiked with bacteriophages. These UF membranes tested in this work were designed for drinking water treatment market and were also selected for research purpose. The hypothesis serving as base for this study was that the interfacial properties for these three bacteriophages, in terms of electrostatic charge and the degree of hydrophobicity, could induce variations in the removal performances achieved by drinking water treatments. The comparison of the results showed a similar behaviour for both MS2 and Qβ surrogates whereas it was particularly atypical for the GA surrogate. The infectious character of MS2 and Qβ bacteriophages was mostly removed after clarification followed by sand filtration processes (more than a 4.8-log reduction) while genomic copies were removed at more than a 4.0-log after the complete treatment process. On the contrary, GA bacteriophage was only slightly removed by clarification followed by sand filtration, with less than 1.7-log and 1.2-log reduction, respectively. After the complete treatment process achieved, GA bacteriophage was removed with less than 2.2-log and 1.6-log reduction, respectively. The effectiveness of the three UF membranes tested in terms of bacteriophages removal showed significant differences, especially for GA bacteriophage. These results could provide recommendations for drinking water suppliers in terms of selection criteria for membranes. MS2 bacteriophage is widely used as a surrogate for pathogenic waterborne viruses in Europe and the United States. In this study, the choice of MS2 bacteriophage as the best surrogate to be used for assessment of the effectiveness of drinking water treatment in removal of pathogenic waterborne viruses in worst conditions is clearly challenged. It was shown that GA bacteriophage is potentially a better surrogate as a worst case than MS2. Considering GA bacteriophage as the best surrogate in this study, a chlorine disinfection step could guaranteed a complete removal of this model and ensure the safety character of drinking water plants. Copyright © 2012 Elsevier Ltd. All rights reserved.
Brar, A P S; Sood, N K; Kaur, P; Singla, L D; Sandhu, B S; Gupta, K; Narang, D; Singh, C K; Chandra, M
2017-10-01
Bovine calf scours reported to be caused by multiple aetiologies resulting in heavy mortality in unweaned calves and huge economic loss to the dairy farmers. Among these, cryptosporidiosis is an emerging waterborne zoonoses and one of the important causes of neonatal calf diarrhoea. Poor immune response coupled with primary cryptosporidial infections predispose neonatal calves to multiple secondary infections resulting in their deaths. In the present study, faecal samples from 100 diarrhoeic calves randomly picked up out of 17 outbreaks of bovine calf diarrhoea in periurban Ludhiana, Punjab in Northern India were subjected to conventional (microscopy, modified Zeihl-Neelsen (mZN) staining) and immunological and molecular techniques (faecal antigen capture ELISA and PCR) for detection of primary Cryptosporidium parvum infection as well as other frequently reported concurrent pathogens, viz. rotavirus and coronavirus, Salmonella spp., Escherichia coli, Clostridium perfringens and Eimeria spp. The faecal antigen capture ELISA and PCR revealed 35% prevalence of C. parvum in contrast to 25% by mZN staining with a relatively higher prevalence (66·7%) in younger (8-14-day-old) calves. The detection rate of the other enteropathogens associated with C. parvum was 45·71% for C. perfringens followed by Salmonella spp (40·0%), rotavirus (36·0%), coronavirus (16·0%), E. coli (12·0%) and Eimeria spp (4·0%) The sensitivity for detection of C. parvum by ELISA and mZN staining in comparison to PCR was 97·14% and 72·72%, respectively. An important finding of the study was that C. parvum alone was found in only 10% of the diarrhoeic faecal samples, whereas, majority of the samples (90%) showed mixed infections ranging from a combination of two to five agents. This is the first documentary proof of C. parvum and associated pathogens responsible for severe periurban outbreaks of bovine calf diarrhoea culminating in heavy mortality from Northern India.
A mouse model of Salmonella typhi infection
Mathur, Ramkumar; Oh, Hyunju; Zhang, Dekai; Park, Sung-Gyoo; Seo, Jin; Koblansky, Alicia; Hayden, Matthew S.; Ghosh, Sankar
2012-01-01
Salmonella spp. are gram-negative flagellated bacteria that can cause food and water-borne gastroenteritis and typhoid fever in humans. We now report that flagellin from Salmonella spp. is recognized in mouse intestine by Toll-like receptor 11 (TLR11). Absence of TLR11 renders mice more susceptible to infection by S. typhimurium, with increased dissemination of the bacteria and enhanced lethality. Unlike S. typhimurium, S. typhi, a human obligatory pathogen that causes typhoid fever, is normally unable to infect mice. TLR11 is expressed in mice but not in humans, and remarkably, we find that tlr11−/− mice are efficiently infected with orally-administered S. typhi. We also find that tlr11−/− mice can be immunized against S. typhi. Therefore, tlr11−/− mice represent the first small animal model for the study of the immune response to S. typhi, and for the development of vaccines against this important human pathogen. PMID:23101627
Quartz-Crystal Microbalance (QCM) for Public Health: An Overview of Its Applications.
Bragazzi, Nicola Luigi; Amicizia, Daniela; Panatto, Donatella; Tramalloni, Daniela; Valle, Ivana; Gasparini, Roberto
2015-01-01
Nanobiotechnologies, from the convergence of nanotechnology and molecular biology and postgenomics medicine, play a major role in the field of public health. This overview summarizes the potentiality of piezoelectric sensors, and in particular, of quartz-crystal microbalance (QCM), a physical nanogram-sensitive device. QCM enables the rapid, real time, on-site detection of pathogens with an enormous burden in public health, such as influenza and other respiratory viruses, hepatitis B virus (HBV), and drug-resistant bacteria, among others. Further, it allows to detect food allergens, food-borne pathogens, such as Escherichia coli and Salmonella typhimurium, and food chemical contaminants, as well as water-borne microorganisms and environmental contaminants. Moreover, QCM holds promises in early cancer detection and screening of new antiblastic drugs. Applications for monitoring biohazards, for assuring homeland security, and preventing bioterrorism are also discussed. © 2015 Elsevier Inc. All rights reserved.
Methylobacterium spp. as an indicator for the presence or absence of Mycobacterium spp.
Falkinham, Joseph O; Williams, Myra D; Kwait, Rebecca; Lande, Leah
2016-06-01
A published survey of bacteria in showerhead biofilm samples revealed that Methylobacterium spp. and Mycobacterium spp. seldom coexisted in biofilms. To confirm that information, biofilm samples were collected from household plumbing of Mycobacterium avium patients and Methylobacterium spp. and M. avium numbers were measured by direct colony counts. The results demonstrated that if Methylobacterium spp. were present, Mycobacterium spp. were absent, and the opposite. The data demonstrate that microbial populations in biofilms can influence the presence or absence of opportunistic premise plumbing pathogens and, thereby, increase the range of strategies to reduce exposure to waterborne pathogens. Finally, by assessing for the visual presence of methylobacteria as pink pigmentation on showers and shower curtains, homeowners and managers of hospitals and other buildings can quickly determine whether a premise plumbing biofilm sample has mycobacteria with a high degree of assurance. Copyright © 2016 Asian African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.
A real-time early warning system for pathogens in water
NASA Astrophysics Data System (ADS)
Adams, John A.; McCarty, David; Crousore, Kristina
2006-05-01
The events of September 11, 2001 represented an escalation in the means and effects of terrorist attacks and raised awareness of the vulnerability of major infrastructures such as transportation, finance, power and energy, communications, food, and water. A re-examination of the security of critical assets was initiated. Actions were taken in the United States to protect our drinking water. Anti-terrorism monitoring systems that allow us to take action before contaminated water can reach the consumer have been under development since then. This presentation will discuss the current performance of a laser-based, multi-angle light scattering (MALS) technology for continuous, real-time detection and classification of microorganisms for security applications in all drinking and process water applications inclusive of protection of major assets, potable and distributed water. Field test data for a number of waterborne pathogens will also be presented.
PROBLEM/CONDITION: Since 1971, CDC, the U.S. Environmental Protection Agency, and the Council of State and Territorial Epidemiologists have collaboratively maintained the Waterborne Disease and Outbreak Surveillance System for collecting and reporting data related to waterborne-d...
Deformability Assessment of Waterborne Protozoa Using a Microfluidic-Enabled Force Microscopy Probe
Seddon, James R. T.; Lai, Stanley C. S.; Lemay, Serge G.; Bridle, Helen L.
2016-01-01
Many modern filtration technologies are incapable of the complete removal of Cryptosporidium oocysts from drinking-water. Consequently, Cryptosporidium-contaminated drinking-water supplies can severely implicate both water utilities and consumers. Existing methods for the detection of Cryptosporidium in drinking-water do not discern between non-pathogenic and pathogenic species, nor between viable and non-viable oocysts. Using FluidFM, a novel force spectroscopy method employing microchannelled cantilevers for single-cell level manipulation, we assessed the size and deformability properties of two species of Cryptosporidium that pose varying levels of risk to human health. A comparison of such characteristics demonstrated the ability of FluidFM to discern between Cryptosporidium muris and Cryptosporidium parvum with 86% efficiency, whilst using a measurement throughput which exceeded 50 discrete oocysts per hour. In addition, we measured the deformability properties for untreated and temperature-inactivated oocysts of the highly infective, human pathogenic C. parvum to assess whether deformability may be a marker of viability. Our results indicate that untreated and temperature-inactivated C. parvum oocysts had overlapping but significantly different deformability distributions. PMID:26938220
Wu, Jianyong; Gronewold, Andrew D; Rodriguez, Roberto A; Stewart, Jill R; Sobsey, Mark D
2014-02-01
Rapid quantification of viral pathogens in drinking and recreational water can help reduce waterborne disease risks. For this purpose, samples in small volume (e.g. 1L) are favored because of the convenience of collection, transportation and processing. However, the results of viral analysis are often subject to uncertainty. To overcome this limitation, we propose an approach that integrates Bayesian statistics, efficient concentration methods, and quantitative PCR (qPCR) to quantify viral pathogens in water. Using this approach, we quantified human adenoviruses (HAdVs) in eighteen samples of source water collected from six drinking water treatment plants. HAdVs were found in seven samples. In the other eleven samples, HAdVs were not detected by qPCR, but might have existed based on Bayesian inference. Our integrated approach that quantifies uncertainty provides a better understanding than conventional assessments of potential risks to public health, particularly in cases when pathogens may present a threat but cannot be detected by traditional methods. © 2013 Elsevier B.V. All rights reserved.
Global Occurrence and Emission of Rotaviruses to Surface Waters
Kiulia, Nicholas M.; Hofstra, Nynke; Vermeulen, Lucie C.; Obara, Maureen A.; Medema, Gertjan; Rose, Joan B.
2015-01-01
Group A rotaviruses (RV) are the major cause of acute gastroenteritis in infants and young children globally. Waterborne transmission of RV and the presence of RV in water sources are of major public health importance. In this paper, we present the Global Waterborne Pathogen model for RV (GloWPa-Rota model) to estimate the global distribution of RV emissions to surface water. To our knowledge, this is the first model to do so. We review the literature to estimate three RV specific variables for the model: incidence, excretion rate and removal during wastewater treatment. We estimate total global RV emissions to be 2 × 1018 viral particles/grid/year, of which 87% is produced by the urban population. Hotspot regions with high RV emissions are urban areas in densely populated parts of the world, such as Bangladesh and Nigeria, while low emissions are found in rural areas in North Russia and the Australian desert. Even for industrialized regions with high population density and without tertiary treatment, such as the UK, substantial emissions are estimated. Modeling exercises like the one presented in this paper provide unique opportunities to further study these emissions to surface water, their sources and scenarios for improved management. PMID:25984911
Laine, J; Huovinen, E; Virtanen, M J; Snellman, M; Lumio, J; Ruutu, P; Kujansuu, E; Vuento, R; Pitkänen, T; Miettinen, I; Herrala, J; Lepistö, O; Antonen, J; Helenius, J; Hänninen, M-L; Maunula, L; Mustonen, J; Kuusi, M
2011-07-01
An inappropriate cross-connection between sewage- and drinking-water pipelines contaminated tap water in a Finnish town, resulting in an extensive waterborne gastroenteritis outbreak in this developed country. According to a database and a line-list, altogether 1222 subjects sought medical care as a result of this exposure. Seven pathogens were found in patient samples of those who sought treatment. To establish the true disease burden from this exposure, we undertook a population-based questionnaire investigation with a control population, infrequently used to study waterborne outbreaks. The study covered three areas, contaminated and uncontaminated parts of the town and a control town. An estimated 8453 residents fell ill during the outbreak, the excess number of illnesses being 6501. Attack rates were 53% [95% confidence interval (CI) 49.5-56.4] in the contaminated area, 15.6% (95% CI 13.1-18.5) in the uncontaminated area and 6.5% (95% CI 4.8-8.8) in the control population. Using a control population allowed us to differentiate baseline morbidity from the observed morbidity caused by the water contamination, thus enabling a more accurate estimate of the disease burden of this outbreak.
Invik, Jesse; Barkema, Herman W; Massolo, Alessandro; Neumann, Norman F; Checkley, Sylvia
2017-10-01
With increasing stress on our water resources and recent waterborne disease outbreaks, understanding the epidemiology of waterborne pathogens is crucial to build surveillance systems. The purpose of this study was to explore techniques for describing microbial water quality in rural drinking water wells, based on spatiotemporal analysis, time series analysis and relative risk mapping. Tests results for Escherichia coli and coliforms from private and small public well water samples, collected between 2004 and 2012 in Alberta, Canada, were used for the analysis. Overall, 14.6 and 1.5% of the wells were total coliform and E. coli-positive, respectively. Private well samples were more often total coliform or E. coli-positive compared with untreated public well samples. Using relative risk mapping we were able to identify areas of higher risk for bacterial contamination of groundwater in the province not previously identified. Incorporation of time series analysis demonstrated peak contamination occurring for E. coli in July and a later peak for total coliforms in September, suggesting a temporal dissociation between these indicators in terms of groundwater quality, and highlighting the potential need to increase monitoring during certain periods of the year.
Ahmad, Farhan; Stedtfeld, Robert D; Waseem, Hassan; Williams, Maggie R; Cupples, Alison M; Tiedje, James M; Hashsham, Syed A
2017-01-01
We are reporting a most probable number approach integrated to loop mediated isothermal technique (MPN-LAMP) focusing on Gram-negative Escherichia coli and Gram-positive Enterococcus faecalis bacterial cells without nucleic acids extraction. LAMP assays for uidA from E. coli and gelE from E. faecalis were successfully performed directly on cells up to single digit concentration using a commercial real time PCR instrument. Threshold time values of LAMP assays of bacterial cells, heat treated bacterial cells (95°C for 5min), and their purified genomic DNA templates were similar, implying that amplification could be achieved directly from bacterial cells at 63°C. Viability of bacterial cells was confirmed by using propidium monoazide in a LAMP assay with E. faecalis. To check its functionality on a microfluidic platform, MPN-LAMP assays targeting <10CFU of bacteria were also translated onto polymeric microchips and monitored by a low-cost fluorescence imaging system. The overall system provided signal-to-noise (SNR) ratios up to 800, analytical sensitivity of <10CFU, and time to positivity of about 20min. MPN-LAMP assays were performed for cell concentrations in the range of 10 5 CFU to <10CFU. MPN values from LAMP assays confirmed that the amplifications were from <10CFU. The method described here, applicable directly on cells at 63°C, eliminates the requirement of complex nucleic acids extraction steps, facilitating the development of sensitive, rapid, low-cost, and field-deployable systems. This rapid MPN-LAMP approach has the potential to replace conventional MPN method for waterborne pathogens. Copyright © 2016 Elsevier B.V. All rights reserved.
Kim, Jun-Hwan; Kang, Ju-Chan
2016-10-01
Juvenile rockfish, Sebastes schlegelii (mean length 16.4±1.9cm, and mean weight 71.6±6.4g) were exposed for 20days with the different levels of waterborne arsenic concentration (0, 50, 100, 200 and 400μg/L). The plasma cortisol of S. schlegelii was significantly increased by the waterborne arsenit exposure. In the immune responses, the immunoglobulin M (Ig M) and lysozyme activity of S. schlegelii were significantly increased by the waterborne arsenic exposure. The acetylcholinesterase (AChE) activity of S. schlegelii was inhibited by the waterborne arsenic exposure. The substantial increases in the gene expression such as metallothionein (MT) and heat shock protein 70 (HSP 70) were observed by the waterborne arsenic exposure. The results demonstrated that waterborne arsenic exposure can induce the significant alterations in the immune responses and specific gene expression of S. schlegelii. Copyright © 2016 Elsevier B.V. All rights reserved.
Fate and transport of pathogens in lakes and reservoirs.
Brookes, Justin D; Antenucci, Jason; Hipsey, Matthew; Burch, Michael D; Ashbolt, Nicholas J; Ferguson, Christobel
2004-07-01
Outbreaks of water-borne disease via public water supplies continue to be reported in developed countries even though there is increased awareness of, and treatment for, pathogen contamination. Pathogen episodes in lakes and reservoirs are often associated with rain events, and the riverine inflow is considered to be major source of pathogens. Consequently, the behaviour of these inflows is of particular importance in determining pathogen transport and distribution. Inflows are controlled by their density relative to that of the lake, such that warm inflows will flow over the surface of the lake as a buoyant surface flow and cold, dense inflows will sink beneath the lake water where they will flow along the bathymetry towards the deepest point. The fate of pathogens is determined by loss processes including settling and inactivation by temperature, UV and grazing. The general trend is for the insertion timescale to be shortest, followed by sedimentation losses and temperature inactivity. The fate of Cryptosporidium due to UV light inactivation can occur at opposite ends of the scale, depending on the location of the oocysts in the water column and the extinction coefficient for UV light. For this reason, the extinction coefficient for UV light appears to be a vitally important parameter for determining the risk of Cryptosporidium contamination. For risk assessment of pathogens in supply reservoirs, it is important to understand the role of hydrodynamics in determining the timescale of transport to the off-take relative to the timescale of inactivation. The characteristics of the riverine intrusion must also be considered when designing a sampling program for pathogens. A risk management framework is presented that accounts for pathogen fate and transport for reservoirs.
USDA-ARS?s Scientific Manuscript database
We have identified an atypical strain of Toxoplasmagondii as the causative agent of the 2001 outbreak of toxoplasmosis in Santa Isabel do Ivai, Brazil, which resulted in approximately 426 human infections. The epidemic clone was isolated from multiple water filters collected from a cistern linked ep...
The virulence of multiple Aeromonas spp. were assessed using two models, a neonatal mouse assay and a mouse intestinal cell culture. Transcriptional responses to both infection models were assessed using microarrays. After artificial infection with a variety of Aeromonas spp., ...
Burnet, Jean-Baptiste; Ogorzaly, Leslie; Penny, Christian; Cauchie, Henry-Michel
2015-01-01
Background: The occurrence of faecal pathogens in drinking water resources constitutes a threat to the supply of safe drinking water, even in industrialized nations. To efficiently assess and monitor the risk posed by these pathogens, sampling deserves careful design, based on preliminary knowledge on their distribution dynamics in water. For the protozoan pathogens Cryptosporidium and Giardia, only little is known about their spatial distribution within drinking water supplies, especially at fine scale. Methods: Two-dimensional distribution maps were generated by sampling cross-sections at meter resolution in two different zones of a drinking water reservoir. Samples were analysed for protozoan pathogens as well as for E. coli, turbidity and physico-chemical parameters. Results: Parasites displayed heterogeneous distribution patterns, as reflected by significant (oo)cyst density gradients along reservoir depth. Spatial correlations between parasites and E. coli were observed near the reservoir inlet but were absent in the downstream lacustrine zone. Measurements of surface and subsurface flow velocities suggest a role of local hydrodynamics on these spatial patterns. Conclusion: This fine-scale spatial study emphasizes the importance of sampling design (site, depth and position on the reservoir) for the acquisition of representative parasite data and for optimization of microbial risk assessment and monitoring. Such spatial information should prove useful to the modelling of pathogen transport dynamics in drinking water supplies. PMID:26404350
A Family of Indoles Regulate Virulence and Shiga Toxin Production in Pathogenic E. coli
Izrayelit, Yevgeniy; Bhatt, Shantanu; Cartwright, Emily; Wang, Wei; Swimm, Alyson I.; Benian, Guy M.; Schroeder, Frank C.; Kalman, Daniel
2013-01-01
Enteropathogenic Escherichia coli (EPEC), enterohemorrhagic E. coli (EHEC) and enteroaggregative E. coli (EAEC) are intestinal pathogens that cause food and water-borne disease in humans. Using biochemical methods and NMR-based comparative metabolomics in conjunction with the nematode Caenorhabditis elegans, we developed a bioassay to identify secreted small molecules produced by these pathogens. We identified indole, indole-3-carboxaldehyde (ICA), and indole-3-acetic acid (IAA), as factors that only in combination are sufficient to kill C. elegans. Importantly, although lethal to C. elegans, these molecules downregulate several bacterial processes important for pathogenesis in mammals. These include motility, biofilm formation and production of Shiga toxins. Some pathogenic E. coli strains are known to contain a Locus of Enterocyte Effacement (LEE), which encodes virulence factors that cause “attaching and effacing” (A/E) lesions in mammals, including formation of actin pedestals. We found that these indole derivatives also downregulate production of LEE virulence factors and inhibit pedestal formation on mammalian cells. Finally, upon oral administration, ICA inhibited virulence and promoted survival in a lethal mouse infection model. In summary, the C. elegans model in conjunction with metabolomics has facilitated identification of a family of indole derivatives that broadly regulate physiology in E. coli, and virulence in pathogenic strains. These molecules may enable development of new therapeutics that interfere with bacterial small-molecule signaling. PMID:23372726
Sensitive-cell-based fish chromatophore biosensor
NASA Astrophysics Data System (ADS)
Plant, Thomas K.; Chaplen, Frank W.; Jovanovic, Goran; Kolodziej, Wojtek; Trempy, Janine E.; Willard, Corwin; Liburdy, James A.; Pence, Deborah V.; Paul, Brian K.
2004-07-01
A sensitive biosensor (cytosensor) has been developed based on color changes in the toxin-sensitive colored living cells of fish. These chromatophores are highly sensitive to the presence of many known and unknown toxins produced by microbial pathogens and undergo visible color changes in a dose-dependent manner. The chromatophores are immobilized and maintained in a viable state while potential pathogens multiply and fish cell-microbe interactions are monitored. Low power LED lighting is used to illuminate the chromatophores which are magnified using standard optical lenses and imaged onto a CCD array. Reaction to toxins is detected by observing changes is the total area of color in the cells. These fish chromatophores are quite sensitive to cholera toxin, Staphococcus alpha toxin, and Bordatella pertussis toxin. Numerous other toxic chemical and biological agents besides bacterial toxins also cause readily detectable color effects in chromatophores. The ability of the chromatophore cell-based biosensor to distinguish between different bacterial pathogens was examined. Toxin producing strains of Salmonella enteritis, Vibrio parahaemolyticus, and Bacillus cereus induced movement of pigmented organelles in the chromatophore cells and this movement was measured by changes in the optical density over time. Each bacterial pathogen elicited this measurable response in a distinctive and signature fashion. These results suggest a chromatophore cell-based biosensor assay may be applicable for the detection and identification of virulence activities associated with certain air-, food-, and water-borne bacterial pathogens.
Surveillance Systems for Waterborne Protozoa: Beyond Method 1623
1. Brief introduction to waterborne Cryptosporidium and Giardia Historical perspective on detecting Cryptosporidium and Giardia Current detection methodologies 2. US EPA’s waterborne protozoan research program Building a “Protoz...
Surveillance Systems for Waterborne Protozoa Past, Present and Future
OVERVIEW I. Brief introduction to waterborne Cryptosporidium Historical perspective on detecting Cryptosporidium Current detection methodologies II. US EPA’s waterborne protozoan research program Detecting, typing, and tracking sources of Cryptosporidium contami...
Sokolow, S. H.; Ngonghala, C. N.; Jocque, M.; Lund, A.; Barry, M.; Mordecai, E. A.; Daily, G. C.; Andrews, J. R.; Bendavid, E.; Luby, S. P.; LaBeaud, A. D.; Seetah, K.; Guégan, J. F.; De Leo, G. A.
2017-01-01
Reducing the burden of neglected tropical diseases (NTDs) is one of the key strategic targets advanced by the Sustainable Development Goals. Despite the unprecedented effort deployed for NTD elimination in the past decade, their control, mainly through drug administration, remains particularly challenging: persistent poverty and repeated exposure to pathogens embedded in the environment limit the efficacy of strategies focused exclusively on human treatment or medical care. Here, we present a simple modelling framework to illustrate the relative role of ecological and socio-economic drivers of environmentally transmitted parasites and pathogens. Through the analysis of system dynamics, we show that periodic drug treatments that lead to the elimination of directly transmitted diseases may fail to do so in the case of human pathogens with an environmental reservoir. Control of environmentally transmitted diseases can be more effective when human treatment is complemented with interventions targeting the environmental reservoir of the pathogen. We present mechanisms through which the environment can influence the dynamics of poverty via disease feedbacks. For illustration, we present the case studies of Buruli ulcer and schistosomiasis, two devastating waterborne NTDs for which control is particularly challenging. This article is part of the themed issue ‘Conservation, biodiversity and infectious disease: scientific evidence and policy implications’. PMID:28438917
Characterizing relationships among fecal indicator bacteria ...
Bed sediments of streams and rivers may store high concentrations of fecal indicator bacteria (FIB) and pathogens. Due to resuspension events, these contaminants can be mobilized into the water column and affect overall water quality. Other bacterial indicators such as microbial source tracking (MST) markers, developed to determine potential sources of fecal contamination, can also be resuspended from bed sediments. The primary objective of this study was to predict occurrence of waterborne pathogens in water and streambed sediments using a simple statistical model that includes traditionally measured FIB, environmental parameters and source allocation, using MST markers as predictor variables. Synoptic sampling events were conducted during baseflow conditions downstream from agricultural (AG), forested (FORS), and wastewater pollution control plant (WPCP) land uses. Concentrations of FIB and MST markers were measured in water and sediments, along with occurrences of the enteric pathogens Campylobacter, Listeria and Salmonella, and the virulence gene that carries Shiga toxin, stx2. Pathogens were detected in water more often than in underlying sediments. Shiga toxin was significantly related to land use, with concentrations of the ruminant marker selected as an independent variable that could correctly classify 76% and 64% of observed Shiga toxin occurrences in water and sediment, respectively. FIB concentrations and water quality parameters were also selected a
Water Filtration Using Plant Xylem
Chambers, Valerie; Venkatesh, Varsha; Karnik, Rohit
2014-01-01
Effective point-of-use devices for providing safe drinking water are urgently needed to reduce the global burden of waterborne disease. Here we show that plant xylem from the sapwood of coniferous trees – a readily available, inexpensive, biodegradable, and disposable material – can remove bacteria from water by simple pressure-driven filtration. Approximately 3 cm3 of sapwood can filter water at the rate of several liters per day, sufficient to meet the clean drinking water needs of one person. The results demonstrate the potential of plant xylem to address the need for pathogen-free drinking water in developing countries and resource-limited settings. PMID:24587134
Nosocomial legionellosis and invasive aspergillosis in a child with T-lymphoblastic leukemia.
Furtwängler, Rhoikos; Schlotthauer, Uwe; Gärtner, Barbara; Graf, Norbert; Simon, Arne
2017-07-01
Invasive aspergillosis of the lungs and the central nervous system and Legionella pneumophilia serotype 1 infection of the lungs were diagnosed in a 22-month old child during inpatient induction treatment for T-lymphoblastic leukemia. Environmental investigations i.e. samples from the hospital water system did not reveal any Legionella. The patient may have been exposed to waterborne pathogens despite terminal water filtration due to a technical device to release residual tap water from the hose after showering. A sodium chloride nose spray was found to be contaminated with the A. fumigatus isolate of the patient. Copyright © 2017 Elsevier GmbH. All rights reserved.
A Guide to the Investigation of Waterborne Outbreaks
ERIC Educational Resources Information Center
Rosenberg, Mark L.
1977-01-01
Explained is the process of investigating an alleged waterborne disease outbreak. The information is designed to help water personnel work more effectively with health authorities in tracing, controlling, and preventing waterborne disease. (Author/MA)
Merkx-Jacques, Alexandra; Coors, Anja; Brousseau, Roland; Masson, Luke; Mazza, Alberto; Tien, Yuan-Ching; Topp, Edward
2013-04-01
The detection and abundance of Escherichia coli in water is used to monitor and mandate the quality of drinking and recreational water. Distinguishing commensal waterborne E. coli isolates from those that cause diarrhea or extraintestinal disease in humans is important for quantifying human health risk. A DNA microarray was used to evaluate the distribution of virulence genes in 148 E. coli environmental isolates from a watershed in eastern Ontario, Canada, and in eight clinical isolates. Their pathogenic potential was evaluated with Caenorhabditis elegans, and the concordance between the bioassay result and the pathotype deduced by genotyping was explored. Isolates identified as potentially pathogenic on the basis of their complement of virulence genes were significantly more likely to be pathogenic to C. elegans than those determined to be potentially nonpathogenic. A number of isolates that were identified as nonpathogenic on the basis of genotyping were pathogenic in the infection assay, suggesting that genotyping did not capture all potentially pathogenic types. The detection of the adhesin-encoding genes sfaD, focA, and focG, which encode adhesins; of iroN2, which encodes a siderophore receptor; of pic, which encodes an autotransporter protein; and of b1432, which encodes a putative transposase, was significantly associated with pathogenicity in the infection assay. Overall, E. coli isolates predicted to be pathogenic on the basis of genotyping were indeed so in the C. elegans infection assay. Furthermore, the detection of C. elegans-infective environmental isolates predicted to be nonpathogenic on the basis of genotyping suggests that there are hitherto-unrecognized virulence factors or combinations thereof that are important in the establishment of infection.
Safety of community drinking-water and outbreaks of waterborne enteric disease: Israel, 1976-97.
Tulchinsky, T. H.; Burla, E.; Clayman, M.; Sadik, C.; Brown, A.; Goldberger, S.
2000-01-01
Waterborne disease remains a major public health problem in many countries. We report findings on nearly three decades of waterborne disease in Israel and the part these diseases play in the total national burden of enteric disease. During the 1970s and 1980s, Israel's community water supplies were frequently of poor quality according to the microbiological standards at that time, and the country experienced many outbreaks of waterborne enteric disease. New regulations raised water quality standards and made chlorination of community water supplies mandatory, as well as imposing more stringent guidelines on maintaining water sources and distribution systems for both surface water and groundwater. This was followed by improved compliance and water quality, and a marked decline in the number of outbreaks of waterborne disease; no outbreaks were detected between 1992 and 1997. The incidence of waterborne salmonellosis, shigellosis, and typhoid declined markedly as proportions of the total burden of these diseases, but peaked during the time in which there were frequent outbreaks of waterborne disease (1980-85). Long-term trends in the total incidence of reported infectious enteric diseases from all sources, including typhoid, shigellosis, and viral hepatitis (all types) declined, while the total incidence of salmonellosis increased. Mandatory chlorination has had an important impact on improving water quality, in reducing outbreaks of waterborne disease in Israel, and reducing the total burden of enteric disease in the country. PMID:11196499
WATERBORNE OUTBREAKS IN THE UNITED STATES, 1971-81
Since 1971 the Environmental Protection Agency and the Center for Disease Control have cooperated in the investigation and reporting of waterborne outbreaks in the United States. Three hundred and twenty waterborne outbeaks affecting 77,989 individuals were reported during 1971-8...
SUMMARY OF WATERBORNE ILLNESS TRANSMITTED THROUGH CONTAMINATED GROUNDWATER
The use of contaminated, untreated or inadequately treated groundwater was responsible for 51 percent of all waterborne outbreaks and 40 percent of all waterborne illness reported in the United States during the period 1971-82. Contaminated, untreated or inadequately disinfected ...
Onyango, Laura A.; Quinn, Chloe; Tng, Keng H.; Wood, James G.; Leslie, Greg
2015-01-01
Potable reuse is implemented in several countries around the world to augment strained water supplies. This article presents a public health perspective on potable reuse by comparing the critical infrastructure and institutional capacity characteristics of two well-established potable reuse schemes with conventional drinking water schemes in developed nations that have experienced waterborne outbreaks. Analysis of failure events in conventional water systems between 2003 and 2013 showed that despite advances in water treatment technologies, drinking water outbreaks caused by microbial contamination were still frequent in developed countries and can be attributed to failures in infrastructure or institutional practices. Numerous institutional failures linked to ineffective treatment protocols, poor operational practices, and negligence were detected. In contrast, potable reuse schemes that use multiple barriers, online instrumentation, and operational measures were found to address the events that have resulted in waterborne outbreaks in conventional systems in the past decade. Syndromic surveillance has emerged as a tool in outbreak detection and was useful in detecting some outbreaks; increases in emergency department visits and GP consultations being the most common data source, suggesting potential for an increasing role in public health surveillance of waterborne outbreaks. These results highlight desirable characteristics of potable reuse schemes from a public health perspective with potential for guiding policy on surveillance activities. PMID:27053920
Onyango, Laura A; Quinn, Chloe; Tng, Keng H; Wood, James G; Leslie, Greg
2015-01-01
Potable reuse is implemented in several countries around the world to augment strained water supplies. This article presents a public health perspective on potable reuse by comparing the critical infrastructure and institutional capacity characteristics of two well-established potable reuse schemes with conventional drinking water schemes in developed nations that have experienced waterborne outbreaks. Analysis of failure events in conventional water systems between 2003 and 2013 showed that despite advances in water treatment technologies, drinking water outbreaks caused by microbial contamination were still frequent in developed countries and can be attributed to failures in infrastructure or institutional practices. Numerous institutional failures linked to ineffective treatment protocols, poor operational practices, and negligence were detected. In contrast, potable reuse schemes that use multiple barriers, online instrumentation, and operational measures were found to address the events that have resulted in waterborne outbreaks in conventional systems in the past decade. Syndromic surveillance has emerged as a tool in outbreak detection and was useful in detecting some outbreaks; increases in emergency department visits and GP consultations being the most common data source, suggesting potential for an increasing role in public health surveillance of waterborne outbreaks. These results highlight desirable characteristics of potable reuse schemes from a public health perspective with potential for guiding policy on surveillance activities.
Tsang, Michael P; Bates, Matthew E; Madison, Marcus; Linkov, Igor
2014-10-07
Assessing the best options among emerging technologies (e.g., new chemicals, nanotechnologies) is complicated because of trade-offs across benefits and risks that are difficult to quantify given limited and fragmented availability of information. This study demonstrates the integration of multicriteria decision analysis (MCDA) and life cycle assessment (LCA) to address technology alternative selection decisions. As a case study, prioritization of six lumber treatment alternatives [micronized copper quaternary (MCQ); alkaline copper quaternary (ACQ); water-borne copper naphthenate (CN); oil-borne copper naphthenate (CNo); water-borne copper quinolate (CQ); and water-borne zinc naphthenate (ZN)] for military use are considered. Multiattribute value theory (MAVT) is used to derive risk and benefit scores. Risk scores are calculated using a cradle-to-gate LCA. Benefit scores are calculated by scoring of cost, durability, and corrosiveness criteria. Three weighting schemes are used, representing Environmental, Military and Balanced stakeholder perspectives. Aggregated scores from all three perspectives show CQ to be the least favorable alterative. MCQ is identified as the most favorable alternative from the Environmental stakeholder perspective. From the Military stakeholder perspective, ZN is determined to be the most favorable alternative, followed closely by MCQ. This type of scoring and ranking of multiple heterogeneous criteria in a systematic and transparent way facilitates better justification of technology selection and regulation.
Iaconelli, M; Muscillo, M; Della Libera, S; Fratini, M; Meucci, L; De Ceglia, M; Giacosa, D; La Rosa, G
2017-03-01
Human enteric viruses are a major cause of waterborne diseases, and can be transmitted by contaminated water of all kinds, including drinking and recreational water. The objectives of the present study were to assess the occurrence of enteric viruses (enterovirus, norovirus, adenovirus, hepatitis A and E virus) in raw and treated wastewaters, in rivers receiving wastewater discharges, and in drinking waters. Wastewater treatment plants' (WWTP) pathogen removal efficiencies by adenovirus quantitative real-time PCR and the presence of infectious enterovirus, by cell culture assays, in treated wastewaters and in surface waters were also evaluated. A total of 90 water samples were collected: raw and treated wastewaters (treated effluents and ultrafiltered water reused for industrial purposes), water from two rivers receiving treated discharges, and drinking water. Nested PCR assays were used for the identification of viral DNA/RNA, followed by direct amplicon sequencing. All raw sewage samples (21/21), 61.9 % of treated wastewater samples (13/21), and 25 % of ultrafiltered water samples (3/12) were contaminated with at least one viral family. Multiple virus families and genera were frequently detected. Mean positive PCRs per sample decreased significantly from raw to treated sewage and to ultrafiltered waters. Moreover, quantitative adenovirus data showed a reduction in excess of 99 % in viral genome copies following wastewater treatment. In surface waters, 78.6 % (22/28) of samples tested positive for one or more viruses by molecular methods, but enterovirus-specific infectivity assays did not reveal infectious particles in these samples. All drinking water samples tested negative for all viruses, demonstrating the effectiveness of treatment in removing viral pathogens from drinking water. Integrated strategies to manage water from all sources are crucial to ensure water quality.
Factors Mediating Environmental Biofilm Formation by Legionella pneumophila.
Abu Khweek, Arwa; Amer, Amal O
2018-01-01
Legionella pneumophila ( L. pneumophila ) is an opportunistic waterborne pathogen and the causative agent for Legionnaires' disease, which is transmitted to humans via inhalation of contaminated water droplets. The bacterium is able to colonize a variety of man-made water systems such as cooling towers, spas, and dental lines and is widely distributed in multiple niches, including several species of protozoa In addition to survival in planktonic phase, L. pneumophila is able to survive and persist within multi-species biofilms that cover surfaces within water systems. Biofilm formation by L. pneumophila is advantageous for the pathogen as it leads to persistence, spread, resistance to treatments and an increase in virulence of this bacterium. Furthermore, Legionellosis outbreaks have been associated with the presence of L. pneumophila in biofilms, even after the extensive chemical and physical treatments. In the microbial consortium-containing L. pneumophila among other organisms, several factors either positively or negatively regulate the presence and persistence of L. pneumophila in this bacterial community. Biofilm-forming L. pneumophila is of a major importance to public health and have impact on the medical and industrial sectors. Indeed, prevention and removal protocols of L. pneumophila as well as diagnosis and hospitalization of patients infected with this bacteria cost governments billions of dollars. Therefore, understanding the biological and environmental factors that contribute to persistence and physiological adaptation in biofilms can be detrimental to eradicate and prevent the transmission of L. pneumophila . In this review, we focus on various factors that contribute to persistence of L. pneumophila within the biofilm consortium, the advantages that the bacteria gain from surviving in biofilms, genes and gene regulation during biofilm formation and finally challenges related to biofilm resistance to biocides and anti-Legionella treatments.
Recent advances in drinking water disinfection: successes and challenges.
Ngwenya, Nonhlanhla; Ncube, Esper J; Parsons, James
2013-01-01
Drinking water is the most important single source of human exposure to gastroenteric diseases, mainly as a result of the ingestion of microbial contaminated water. Waterborne microbial agents that pose a health risk to humans include enteropathogenic bacteria, viruses, and protozoa. Therefore, properly assessing whether these hazardous agents enter drinking water supplies, and if they do, whether they are disinfected adequately, are undoubtedly aspects critical to protecting public health. As new pathogens emerge, monitoring for relevant indicator microorganisms (e.g., process microbial indicators, fecal indicators, and index and model organisms) is crucial to ensuring drinking water safety. Another crucially important step to maintaining public health is implementing Water Safety Plans (WSPs), as is recommended by the current WHO Guidelines for Drinking Water Quality. Good WSPs include creating health-based targets that aim to reduce microbial risks and adverse health effects to which a population is exposed through drinking water. The use of disinfectants to inactivate microbial pathogens in drinking water has played a central role in reducing the incidence of waterborne diseases and is considered to be among the most successful interventions for preserving and promoting public health. Chlorine-based disinfectants are the most commonly used disinfectants and are cheap and easy to use. Free chlorine is an effective disinfectant for bacteria and viruses; however, it is not always effective against C. parvum and G. lamblia. Another limitation of using chlorination is that it produces disinfection by-products (DBPs), which pose potential health risks of their own. Currently, most drinking water regulations aggressively address DBP problems in public water distribution systems. The DBPs of most concern include the trihalomethanes (THMs), the haloacetic acids (HAAs), bromate, and chlorite. However, in the latest edition of the WHO Guidelines for Drinking Water Quality, it is recommended that water disinfection should never be compromised by attempting to control DBPs. The reason for this is that the risks of human illness and death from pathogens in drinking water are much greater than the risks from exposure to disinfectants and disinfection by-products. Nevertheless, if DBP levels exceed regulatory limits, strategies should focus on eliminating organic impurities that foster their formation, without compromising disinfection. As alternatives to chlorine, disinfectants such as chloramines, ozone, chlorine dioxide, and UV disinfection are gaining popularity. Chlorine and each of these disinfectants have individual advantage and disadvantage in terms of cost, efficacy-stability, ease of application, and nature of disinfectant by-products (DBPs). Based on efficiency, ozone is the most efficient disinfectant for inactivating bacteria, viruses, and protozoa. In contrast, chloramines are the least efficient and are not recommended for use as primary disinfectants. Chloramines are favored for secondary water disinfection, because they react more slowly than chlorine and are more persistent in distribution systems. In addition, chloramines produce lower DBP levels than does chlorine, although microbial activity in the distribution system may produce nitrate from monochloramine, when it is used as a residual disinfectant, Achieving the required levels of water quality, particularly microbial inactivation levels, while minimizing DBP formation requires the application of proper risk and disinfection management protocols. In addition, the failure of conventional treatment processes to eliminate critical waterborne pathogens in drinking water demand that improved and/or new disinfection technologies be developed. Recent research has disclosed that nanotechnology may offer solutions in this area, through the use of nanosorbents, nanocatalysts, bioactive nanoparticles, nanostructured catalytic membranes, and nanoparticle-enhanced filtration.
Hart, L.M.; Traxler, G.S.; Garver, K.A.; Richard, J.; Gregg, J.L.; Grady, C.A.; Kurath, G.; Hershberger, P.K.
2011-01-01
Infectious hematopoietic necrosis (IHN) leads to periodic epidemics among certain wild and farmed fish species of the Northeast (NE) Pacific. The source of the IHN virus (IHNV) that initiates these outbreaks remains unknown; however, a leading hypothesis involves viral persistence in marine host species such as Pacific herring Clupea pallasii. Under laboratory conditions we exposed specific pathogen-free (SPF) larval and juvenile Pacific herring to 103 to 104 plaque-forming units (pfu) of IHNV ml–1 by waterborne immersion. Cumulative mortalities among exposed groups were not significantly different from those of negative control groups. After waterborne exposure, IHNV was transiently recovered from the tissues of larvae but absent in tissues of juveniles. Additionally, no evidence of viral shedding was detected in the tank water containing exposed juveniles. After intraperitoneal (IP) injection of IHNV in juvenile herring with 103 pfu, IHNV was recovered from the tissues of sub-sampled individuals for only the first 5 d post-exposure. The lack of susceptibility to overt disease and transient levels of IHNV in the tissues of exposed fish indicate that Pacific herring do not likely serve a major epizootiological role in perpetuation of IHNV among free-ranging sockeye salmon Oncorhynchus nerka and farmed Atlantic salmon Salmo salar in the NE Pacific.
Signor, R S; Ashbolt, N J
2009-12-01
Some national drinking water guidelines provide guidance on how to define 'safe' drinking water. Regarding microbial water quality, a common position is that the chance of an individual becoming infected by some reference waterborne pathogen (e.g. Cryptsporidium) present in the drinking water should < 10(-4) in any year. However the instantaneous levels of risk to a water consumer vary over the course of a year, and waterborne disease outbreaks have been associated with shorter-duration periods of heightened risk. Performing probabilistic microbial risk assessments is becoming commonplace to capture the impacts of temporal variability on overall infection risk levels. A case is presented here for adoption of a shorter-duration reference period (i.e. daily) infection probability target over which to assess, report and benchmark such risks. A daily infection probability benchmark may provide added incentive and guidance for exercising control over short-term adverse risk fluctuation events and their causes. Management planning could involve outlining measures so that the daily target is met under a variety of pre-identified event scenarios. Other benefits of a daily target could include providing a platform for managers to design and assess management initiatives, as well as simplifying the technical components of the risk assessment process.
Johnson, Paul E; Deromedi, Anthony J; Lebaron, Philippe; Catala, Philippe; Cash, Jennifer
2006-12-01
Pathogenic microorganisms are known to cause widespread waterborne disease worldwide. There is an urgent need to develop a technique for the real-time detection of pathogens in environmental samples at low concentrations, <10 microorganisms/ml, in large sample volumes, > or =100 ml. A novel method, Fountain Flowtrade mark cytometry, for the rapid and sensitive detection of individual microorganisms in aqueous samples is presented. Each sample is first incubated with a fluorescent label and then passed as a stream in front of a laser, which excites the label. The fluorescence is detected with a CCD imager as the sample flows toward the imager along its optical axis. The feasibility of Fountain Flow cytometry (FFC) is demonstrated by the detection of Escherichia coli labeled with ChemChrome CV6 and SYBR Gold in buffer and natural river water. Detections of labeled E. coli were made in aqueous suspensions with an efficiency of 96% +/- 14% down to a concentration approximately 200 bacteria/ml. The feasibility of FFC is demonstrated by the detection of E. coli in buffer and natural river water. FFC should apply to the detection of a wide range of pathogenic microorganisms including amoebae.
Surveillance Systems for Waterborne Cryptosporidium: US EPA method 1523 and Beyond
Waterborne cryptosporidiosis remains a significant public health concern in countries around the world. Many species and genotypes of Cryptosporidium contaminate drinking water sources, but C. parvum and C. hominis remain the two predominant species known to cause waterborne dis...
ENDEMIC WATERBORNE DISEASE: BENNETT-TYPE
Bennett et al. attempted to estimate national waterborne disease (endemic and epidemic) in 1985 by using both actual data and estimates by CDC experts. These investigators reported that 940,000 cases of waterborne disease and 900 associated deaths could have occurred in the U.S. ...
Microbial Contamination of Drinking Water and Human Health from Community Water Systems.
Ashbolt, Nicholas J
2015-03-01
A relatively short list of reference viral, bacterial and protozoan pathogens appears adequate to assess microbial risks and inform a system-based management of drinking waters. Nonetheless, there are data gaps, e.g. human enteric viruses resulting in endemic infection levels if poorly performing disinfection and/or distribution systems are used, and the risks from fungi. Where disinfection is the only treatment and/or filtration is poor, cryptosporidiosis is the most likely enteric disease to be identified during waterborne outbreaks, but generally non-human-infectious genotypes are present in the absence of human or calf fecal contamination. Enteric bacteria may dominate risks during major fecal contamination events that are ineffectively managed. Reliance on culture-based methods exaggerates treatment efficacy and reduces our ability to identify pathogens/indicators; however, next-generation sequencing and polymerase chain reaction approaches are on the cusp of changing that. Overall, water-based Legionella and non-tuberculous mycobacteria probably dominate health burden at exposure points following the various societal uses of drinking water.
Schmidt, Radomir; Klemme, David A; Scow, Kate; Hristova, Krassimira
2012-03-30
A pilot-scale sand-based fluidized bed bioreactor (FBBR) was utilized to treat both methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) from a contaminated aquifer. To evaluate the potential for re-use of the treated water, we tested for a panel of water quality indicator microorganisms and potential waterborne pathogens including total coliforms, Escherichia coli, Salmonella and Shigella spp., Campylobacter jejuni, Aeromonas hydrophila, Legionella pneumophila, Vibrio cholerae, Yersinia enterocolytica and Mycobacterium avium in both influent and treated waters from the bioreactor. Total bacteria decreased during FBBR treatment. E. coli, Salmonella and Shigella spp., C. jejuni, V. cholerae, Y. enterocolytica and M. avium were not detected in aquifer water or bioreactor treated water samples. For those pathogens detected, including total coliforms, L. pneumophila and A. hydrophila, numbers were usually lower in treated water than influent samples, suggesting removal during treatment. The detection of particular bacterial species reflected their presence or absence in the influent waters. Copyright © 2012 Elsevier B.V. All rights reserved.
Waterborne Commerce of the United States, calendar year 1998. Part 5 : national summaries
DOT National Transportation Integrated Search
2000-03-01
Waterborne Commerce of the United States, WCUS, Part 5 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, Part 5 provides extensive graphic and tabular...
Waterborne commerce of the United States, calendar year 2001. Part 5 : national summaries
DOT National Transportation Integrated Search
2001-01-01
Waterborne Commerce of the United States, WCUS, Part 5 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. The publication numbers and the geographical areas ...
ESTIMATES OF ENDEMIC WATERBORNE ILLNESS FROM COMMUNITY INTERVENTION STUDIES
The nature and magnitude of endemic waterborne disease are not well characterized in the
United States. Epidemiologic studies of various designs can provide an estimate of the
waterborne attributable risk along with other types of information. Community drinking wat...
Brazeau, Randi H.; Edwards, Marc A.
2013-01-01
Abstract Residential water heating is linked to growth of pathogens in premise plumbing, which is the primary source of waterborne disease in the United States. Temperature and disinfectant residual are critical factors controlling increased concentration of pathogens, but understanding of how each factor varies in different water heater configurations is lacking. A direct comparative study of electric water heater systems was conducted to evaluate temporal variations in temperature and water quality parameters including dissolved oxygen levels, hydrogen evolution, total and soluble metal concentrations, and disinfectant decay. Recirculation tanks had much greater volumes of water at temperature ranges with potential for increased pathogen growth when set at 49°C compared with standard tank systems without recirculation. In contrast, when set at the higher end of acceptable ranges (i.e., 60°C), this relationship was reversed and recirculation systems had less volume of water at risk for pathogen growth compared with conventional systems. Recirculation tanks also tended to have much lower levels of disinfectant residual (standard systems had 40–600% higher residual), 4–6 times as much hydrogen, and 3–20 times more sediment compared with standard tanks without recirculation. On demand tankless systems had very small volumes of water at risk and relatively high levels of disinfectant residual. Recirculation systems may have distinct advantages in controlling pathogens via thermal disinfection if set at 60°C, but these systems have lower levels of disinfectant residual and greater volumes at risk if set at lower temperatures. PMID:24170969
Liu, Linda; Cloutier, Michel; Craiovan, Emilia; Edwards, Mark; Frey, Steven K; Gottschall, Natalie; Lapen, David R; Sunohara, Mark; Topp, Edward; Khan, Izhar U H
2018-05-15
This study compared the impact of controlled tile drainage (CD) and freely draining (FD) systems on the prevalence and quantitative real-time PCR-based enumeration of four major pathogens including Arcobacter butzleri, Campylobacter jejuni, Campylobacter coli, and Helicobacter pylori in tile- and groundwater following a fall liquid swine manure (LSM) application on clay loam field plots. Although the prevalence of all target pathogens were detected in CD and FD systems, the loads of A. butzleri, C. jejuni, and C. coli were significantly lower in CD tile-water (p<0.05), in relation to FD tile-water. However, concentrations of A. butzleri were significantly greater in CD than FD tile-water (p<0.05). In shallow groundwater (1.2m depth), concentrations of A. butzleri, C. coli, and H. pylori showed no significant difference between CD and FD plots, while C. jejuni concentrations were significantly higher in FD plots (p<0.05). No impact of CD on the H. pylori was observed since quantitative detection in tile- and groundwater was scarce. Although speculative, H. pylori occurrence may have been related to the application of municipal biosolids four years prior to the LSM experiment. Overall, CD can be used to help minimize off-field export of pathogens into surface waters following manure applications to land, thereby reducing waterborne pathogen exposure risks to humans. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.
Waterborne Commerce of the United States, calendar year 2000. Part 5 : national summaries
DOT National Transportation Integrated Search
2000-01-01
Waterborne commerce of the United States, WCUS, part 5 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, parts 1-4 present detailed data on the moveme...
Waterborne Commerce of the United States, calendar year 1996. Part 5 : national summaries.
DOT National Transportation Integrated Search
1996-01-01
Waterborne Cmmerce of the United States, WCUS, Part 5 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, Part 5 provides a condensation of this detaile...
MEASURE OCCURRENCE AND EXPOSURE TO WATERBORNE HUMAN VIRUSES
Waterborne outbreaks of virus origin occur at frequencies which require action on the part of the Agency. Yet outbreaks may represent a small fraction of the waterborne disease burden in the U.S. Several recent studies suggest that about 20% of the surface and ground source wat...
DOT National Transportation Integrated Search
1997-01-01
Waterborne Commerce of the United States, WCUS, Part 1 is one of a series publications which provides statistics on foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on movements of vess...
DOT National Transportation Integrated Search
2000-01-01
Waterborne Commerce of the United States, WCUS, Part 1 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on the moveme...
DOT National Transportation Integrated Search
2000-01-01
Waterborne Commerce of the United States, WCUS, Part 1 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on the moveme...
DOT National Transportation Integrated Search
2000-01-01
Waterborne Commerce of the United States, WCUS, Part 3 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on the moveme...
DOT National Transportation Integrated Search
1997-01-01
Waterborne Commerce of the United States, WCUS, Part 5 is one of a series publications which provides statistics on foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on movements of vess...
DOT National Transportation Integrated Search
1997-01-01
Waterborne Commerce of the United States, WCUS, Part 3 is one of a series publications which provides statistics on foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on movements of vess...
DOT National Transportation Integrated Search
2001-01-01
Waterborne Commerce of the United States, WCUS, Part 3 is one of a series of : publications which provides statistics on the foreign and domestic waterborne commerce : moved on the United States waters. WCUS, Parts 1-4 present detailed data on the mo...
Previous work in our laboratory demonstrated toxicity to rainbow trout fed oligochaetes contaminated with arsenic via waterborne exposure. While this demonstrated the potential hazard of dietborne exposure, it did not address the relative and combined potency of waterborne and d...
Background: Since 1978, CDC, EPA, and the Council of State and Territorial Epidemiologists have collaborated on the Waterborne Disease and Outbreak Surveillance System (WBDOSS) to capture data on waterborne disease outbreaks associated with recreational water. WBDOSS is the prima...
2015-01-01
UNCLASSIFIED I N S T I T U T E F O R D E F E N S E A N A L Y S E S Comparison of a Riverine Waterborne Transport ...F E N S E A N A L Y S E S IDA Document D-5330 Comparison of a Riverine Waterborne Transport and Dispersion Model and Yellowstone...tool for predicting waterborne transport and dispersion of hazardous materials. In a preliminary analysis, IDA reviewed the code’s technical
Carbon nanotubes as antimicrobial agents for water disinfection and pathogen control.
Liu, Dan; Mao, Yiqin; Ding, Lijun
2018-04-01
Waterborne diseases significantly affect human health and are responsible for high mortality rates worldwide. Antibiotics have been known for decades for treatment of bacterial strains and their overuse and irrational applications are causing increasing bacteria resistance. Therefore, there is a strong need to find alternative ways for efficient water disinfection and microbial control. Carbon nanotubes (CNTs) have demonstrated strong antimicrobial properties due to their remarkable structure. This paper reviews the antimicrobial properties of CNTs, discusses diverse mechanisms of action against microorganisms as well as their applicability for water disinfection and microbial control. Safety concerns, challenges of CNTs as antimicrobial agents and future opportunities for their application in the water remediation process are also highlighted.
EXPOSURES AND INTERNAL DOSES OF ...
The National Center for Environmental Assessment (NCEA) has released a final report that presents and applies a method to estimate distributions of internal concentrations of trihalomethanes (THMs) in humans resulting from a residential drinking water exposure. The report presents simulations of oral, dermal and inhalation exposures and demonstrates the feasibility of linking the US EPA’s information Collection Rule database with other databases on external exposure factors and physiologically based pharmacokinetic modeling to refine population-based estimates of exposure. Review Draft - by 2010, develop scientifically sound data and approaches to assess and manage risks to human health posed by exposure to specific regulated waterborne pathogens and chemicals, including those addressed by the Arsenic, M/DBP and Six-Year Review Rules.
Drinking water microbial myths.
Allen, Martin J; Edberg, Stephen C; Clancy, Jennifer L; Hrudey, Steve E
2015-01-01
Accounts of drinking water-borne disease outbreaks have always captured the interest of the public, elected and health officials, and the media. During the twentieth century, the drinking water community and public health organizations have endeavored to craft regulations and guidelines on treatment and management practices that reduce risks from drinking water, specifically human pathogens. During this period there also evolved misunderstandings as to potential health risk associated with microorganisms that may be present in drinking waters. These misunderstanding or "myths" have led to confusion among the many stakeholders. The purpose of this article is to provide a scientific- and clinically-based discussion of these "myths" and recommendations for better ensuring the microbial safety of drinking water and valid public health decisions.
Garchitorena, A; Sokolow, S H; Roche, B; Ngonghala, C N; Jocque, M; Lund, A; Barry, M; Mordecai, E A; Daily, G C; Jones, J H; Andrews, J R; Bendavid, E; Luby, S P; LaBeaud, A D; Seetah, K; Guégan, J F; Bonds, M H; De Leo, G A
2017-06-05
Reducing the burden of neglected tropical diseases (NTDs) is one of the key strategic targets advanced by the Sustainable Development Goals. Despite the unprecedented effort deployed for NTD elimination in the past decade, their control, mainly through drug administration, remains particularly challenging: persistent poverty and repeated exposure to pathogens embedded in the environment limit the efficacy of strategies focused exclusively on human treatment or medical care. Here, we present a simple modelling framework to illustrate the relative role of ecological and socio-economic drivers of environmentally transmitted parasites and pathogens. Through the analysis of system dynamics, we show that periodic drug treatments that lead to the elimination of directly transmitted diseases may fail to do so in the case of human pathogens with an environmental reservoir. Control of environmentally transmitted diseases can be more effective when human treatment is complemented with interventions targeting the environmental reservoir of the pathogen. We present mechanisms through which the environment can influence the dynamics of poverty via disease feedbacks. For illustration, we present the case studies of Buruli ulcer and schistosomiasis, two devastating waterborne NTDs for which control is particularly challenging.This article is part of the themed issue 'Conservation, biodiversity and infectious disease: scientific evidence and policy implications'. © 2017 The Author(s).
Quantification of Protozoa and Viruses from Small Water Volumes
Bonilla, J. Alfredo; Bonilla, Tonya D.; Abdelzaher, Amir M.; Scott, Troy M.; Lukasik, Jerzy; Solo-Gabriele, Helena M.; Palmer, Carol J.
2015-01-01
Large sample volumes are traditionally required for the analysis of waterborne pathogens. The need for large volumes greatly limits the number of samples that can be processed. The goals of this study were to compare extraction and detection procedures for quantifying protozoan parasites and viruses from small volumes of marine water. The intent was to evaluate a logistically simpler method of sample collection and processing that would facilitate direct pathogen measures as part of routine monitoring programs. Samples were collected simultaneously using a bilayer device with protozoa capture by size (top filter) and viruses capture by charge (bottom filter). Protozoan detection technologies utilized for recovery of Cryptosporidium spp. and Giardia spp. were qPCR and the more traditional immunomagnetic separation—IFA-microscopy, while virus (poliovirus) detection was based upon qPCR versus plaque assay. Filters were eluted using reagents consistent with the downstream detection technologies. Results showed higher mean recoveries using traditional detection methods over qPCR for Cryptosporidium (91% vs. 45%) and poliovirus (67% vs. 55%) whereas for Giardia the qPCR-based methods were characterized by higher mean recoveries (41% vs. 28%). Overall mean recoveries are considered high for all detection technologies. Results suggest that simultaneous filtration may be suitable for isolating different classes of pathogens from small marine water volumes. More research is needed to evaluate the suitability of this method for detecting pathogens at low ambient concentration levels. PMID:26114244
Quantification of Protozoa and Viruses from Small Water Volumes.
Bonilla, J Alfredo; Bonilla, Tonya D; Abdelzaher, Amir M; Scott, Troy M; Lukasik, Jerzy; Solo-Gabriele, Helena M; Palmer, Carol J
2015-06-24
Large sample volumes are traditionally required for the analysis of waterborne pathogens. The need for large volumes greatly limits the number of samples that can be processed. The aims of this study were to compare extraction and detection procedures for quantifying protozoan parasites and viruses from small volumes of marine water. The intent was to evaluate a logistically simpler method of sample collection and processing that would facilitate direct pathogen measures as part of routine monitoring programs. Samples were collected simultaneously using a bilayer device with protozoa capture by size (top filter) and viruses capture by charge (bottom filter). Protozoan detection technologies utilized for recovery of Cryptosporidium spp. and Giardia spp. were qPCR and the more traditional immunomagnetic separation-IFA-microscopy, while virus (poliovirus) detection was based upon qPCR versus plaque assay. Filters were eluted using reagents consistent with the downstream detection technologies. Results showed higher mean recoveries using traditional detection methods over qPCR for Cryptosporidium (91% vs. 45%) and poliovirus (67% vs. 55%) whereas for Giardia the qPCR-based methods were characterized by higher mean recoveries (41% vs. 28%). Overall mean recoveries are considered high for all detection technologies. Results suggest that simultaneous filtration may be suitable for isolating different classes of pathogens from small marine water volumes. More research is needed to evaluate the suitability of this method for detecting pathogens at low ambient concentration levels.
Liao, Chien-Wei; Chuang, Ting-Wu; Huang, Ying-Chieh; Chou, Chia-Mei; Chiang, Chia-Lien; Lee, Fei-Peng; Hsu, Yun-Ting; Lin, Jia-Wei; Briand, Kennar; Tu, Chia-Ying; Fan, Chia-Kwung
2017-12-01
Intestinal parasitic infections (IPIs) among schoolchildren in Republic of Marshall Islands (RMI) largely remains unknown, thus investigation on IPIs status to establish the baseline data is urgently needed. This cross-sectional study intended to investigate the current IPIs status and associated risk factors among schoolchildren at capital of RMI. Single stool sample from 400 schoolchildren (207 boys and 193 girls) aged 9.73±2.50 yrs old was examined by employing merthiolate-iodine-formaldehyde concentration method. Demographic characteristics, uncomfortable symptoms and risk factors were obtained by questionnaires investigation. The overall prevalence of IPIs in schoolchildren was 22.8% (91/400), of them 24.2% harbored at least 2 different parasites. Notably, the majority was infected by waterborne protozoan parasites (82.4%, 75/91). Nine different intestinal parasites have been identified, of which six were pathogenic including Hook worm, Trichuris trichiura, Enterobius vermicularis, Entamoeba histolytica/dispar, Giardia intestinalis and Blastocystis hominis. Schoolchildren who ever complained dizziness or headache showed a significant higher prevalence of pathogenic IPIs than those who did not (p<0.05). Schoolchildren who lived in urban area than rural area had higher chance to acquire pathogenic IPIs (p=0.03). However, none of risk factors were identified to be associated with pathogenic IPIs. Copyright © 2017 Elsevier B.V. All rights reserved.
Enterococci in the environment
Byappanahalli, Muruleedhara N.; Nevers, Meredith B.; Korajkic, Asja; Staley, Zachery R.; Harwood, Valerie J.
2012-01-01
Enterococci are common, commensal members of gut communities in mammals and birds, yet they are also opportunistic pathogens that cause millions of human and animal infections annually. Because they are shed in human and animal feces, are readily culturable, and predict human health risks from exposure to polluted recreational waters, they are used as surrogates for waterborne pathogens and as fecal indicator bacteria (FIB) in research and in water quality testing throughout the world. Evidence from several decades of research demonstrates, however, that enterococci may be present in high densities in the absence of obvious fecal sources and that environmental reservoirs of these FIB are important sources and sinks, with the potential to impact water quality. This review focuses on the distribution and microbial ecology of enterococci in environmental (secondary) habitats, including the effect of environmental stressors; an outline of their known and apparent sources, sinks, and fluxes; and an overview of the use of enterococci as FIB. Finally, the significance of emerging methodologies, such as microbial source tracking (MST) and empirical predictive models, as tools in water quality monitoring is addressed. The mounting evidence for widespread extraenteric sources and reservoirs of enterococci demonstrates the versatility of the genus Enterococcus and argues for the necessity of a better understanding of their ecology in natural environments, as well as their roles as opportunistic pathogens and indicators of human pathogens.
Ghanbari, Sarah; Ravikumar, Anusha; Seubert, John; Figueira, Silvia
2013-01-01
Contaminated water is a serious concern in many developing countries with severe health consequences particularly for children. Current methods for monitoring waterborne pathogens are often time consuming, expensive, and labor intensive, making them not suitable for these regions. Electrochemical detection in a microfluidic platform offers many advantages such as portability, minimal use of instrumentation, and easy integration with electronics. In many parts of the world, however, the required equipment for pathogen detection through electrochemical sensors is either not available or insufficiently portable, and operators may not be trained to use these sensors and interpret results, ultimately preventing its wide adoption. Counterintuitively, these same regions often have an extensive mobile phone infrastructure, suggesting the possibility of integrating electrochemical detection of bacterial pathogens with a mobile platform. Toward a solution to water quality interventions, we demonstrate a microfluidic electrochemical sensor combined with a mobile interface that detects the sequences from bacterial pathogens, suitable for rapid, affordable, and point-of-care water monitoring. We employ the transduction of DNA hybridization into a readily detectable electric signal by means of a conformational change of DNA stem-loop structure. Using this platform, we successfully demonstrate the detection of as low as 100 nM E. coli sequences and the automatic interpretation and mapping of the detection results via a mobile application. PMID:27170858
Enterococci in the Environment
Byappanahalli, Muruleedhara N.; Nevers, Meredith B.; Korajkic, Asja; Staley, Zachery R.
2012-01-01
Summary: Enterococci are common, commensal members of gut communities in mammals and birds, yet they are also opportunistic pathogens that cause millions of human and animal infections annually. Because they are shed in human and animal feces, are readily culturable, and predict human health risks from exposure to polluted recreational waters, they are used as surrogates for waterborne pathogens and as fecal indicator bacteria (FIB) in research and in water quality testing throughout the world. Evidence from several decades of research demonstrates, however, that enterococci may be present in high densities in the absence of obvious fecal sources and that environmental reservoirs of these FIB are important sources and sinks, with the potential to impact water quality. This review focuses on the distribution and microbial ecology of enterococci in environmental (secondary) habitats, including the effect of environmental stressors; an outline of their known and apparent sources, sinks, and fluxes; and an overview of the use of enterococci as FIB. Finally, the significance of emerging methodologies, such as microbial source tracking (MST) and empirical predictive models, as tools in water quality monitoring is addressed. The mounting evidence for widespread extraenteric sources and reservoirs of enterococci demonstrates the versatility of the genus Enterococcus and argues for the necessity of a better understanding of their ecology in natural environments, as well as their roles as opportunistic pathogens and indicators of human pathogens. PMID:23204362
Daniels, Miles E; Smith, Woutrina A; Jenkins, Marion W
2018-01-01
In many low-income settings, despite improvements in sanitation and hygiene, groundwater sources used for drinking may be contaminated with enteric pathogens such as Cryptosporidium and Giardia, which remain important causes of childhood morbidity. In this study, we examined the contribution of diarrhea caused by Cryptosporidium and Giardia found in groundwater sources used for drinking to the total burden of diarrheal disease among children < 5 in rural India. We studied a population of 3,385 children < 5 years of age in 100 communities of Puri District, Odisha, India. We developed a coupled quantitative microbial risk assessment (QMRA) and susceptible-infected-recovered (SIR) population model based on observed levels of Cryptosporidium and Giardia in improved groundwater sources used for drinking and compared the QMRA-SIR estimates with independently measured all-cause (i.e., all fecal-oral enteric pathogens and exposure pathways) child diarrhea prevalence rates observed in the study population during two monsoon seasons (2012 and 2013). We used site specific and regional studies to inform assumptions about the human pathogenicity of the Cryptosporidium and Giardia species present in local groundwater. In all three human pathogenicity scenarios evaluated, the mean daily risk of Cryptosporidium or Giardia infection (0.06-1.53%), far exceeded the tolerable daily risk of infection from drinking water in the US (< 0.0001%). Depending on which protozoa species were present, median estimates of daily child diarrhea prevalence due to either Cryptosporidium or Giardia infection from drinking water was as high as 6.5% or as low as < 1% and accounted for at least 2.9% and as much as 65.8% of the all-cause diarrhea disease burden measured in children < 5 during the study period. Cryptosporidium tended to account for a greater share of estimated waterborne protozoa infections causing diarrhea than did Giardia. Diarrhea prevalence estimates for waterborne Cryptosporidium infection appeared to be most sensitive to assumptions about the probability of infection from ingesting a single parasite (i.e. the rate parameter in dose-response model), while Giardia infection was most sensitive to assumptions about the viability of parasites detected in groundwater samples. Protozoa in groundwater drinking sources in rural India, even at low concentrations, especially for Cryptosporidium, may account for a significant portion of child diarrhea morbidity in settings were tubewells are used for drinking water and should be more systematically monitored. Preventing diarrheal disease burdens in Puri District and similar settings will benefit from ensuring water is microbiologically safe for consumption and consistent and effective household water treatment is practiced.
Incidences of Waterborne and Foodborne Diseases After Meteorologic Disasters in South Korea.
Na, Wonwoong; Lee, Kyeong Eun; Myung, Hyung-Nam; Jo, Soo-Nam; Jang, Jae-Yeon
Climate change could increase the number of regions affected by meteorologic disasters. Meteorologic disasters can increase the risk of infectious disease outbreaks, including waterborne and foodborne diseases. Although many outbreaks of waterborne diseases after single disasters have been analyzed, there have not been sufficient studies reporting comprehensive analyses of cases occurring during long-term surveillance after multiple disasters, which could provide evidence of whether meteorologic disasters cause infectious disease outbreaks. This study aimed to assess the nationwide short-term changes in waterborne and foodborne disease incidences after a meteorologic disaster. We analyzed cases after all 65 floods and typhoons between 2001 and 2009 using the Korean National Emergency Management Agency's reports. Based on these data, we compared the weekly incidences of Vibrio vulnificus septicemia (VVS), shigellosis, typhoid fever, and paratyphoid fever before, during, and after the disasters, using multivariate Poisson regression models. We also analyzed the interactions between disaster characteristics and the relative risk of each disease. Compared with predisaster incidences, the incidences of VVS and shigellosis were 2.49-fold (95% confidence interval, 1.47-4.22) and 3.10-fold (95% confidence interval, 1.21-7.92) higher, respectively, the second week after the disaster. The incidences of VVS and shigellosis peaked the second week postdisaster and subsequently decreased. The risks of typhoid and paratyphoid fever did not significantly increase throughout the 4 weeks postdisaster. The daily average precipitation interacted with VVS and shigellosis incidences, whereas disaster type only interacted with VVS incidence patterns. The incidences of VVS and shigellosis were associated with meteorologic disasters, and disaster characteristics were associated with the disease incidence patterns postdisaster. These findings provide important comprehensive evidence to develop and support policies for managing and protecting public health after meteorologic disasters. Copyright © 2016 Icahn School of Medicine at Mount Sinai. Published by Elsevier Inc. All rights reserved.
DOT National Transportation Integrated Search
1997-01-01
Waterborne Commerce of the United States, WCUS, Part 4 is one of a series publications which provides statistics on foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on movements of vess...
DOT National Transportation Integrated Search
2001-01-01
Waterborne Commerce of the United States, WCUS, Part 4 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on the moveme...
DOT National Transportation Integrated Search
2001-01-01
Waterborne Commerce of the United States, WCUS, Part 2 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on the moveme...
DOT National Transportation Integrated Search
1997-01-01
Waterborne Commerce of the United States, WCUS, Part 2 is one of a series publications which provides statistics on foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on movements of vess...
DOT National Transportation Integrated Search
2001-01-01
Waterborne Commerce of the United States, WCUS, Part 2 is one of a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, Parts 1-4 present detailed data on the moveme...
DOT National Transportation Integrated Search
2002-02-01
Waterborne Commerce of the United States, WCUS, part 4 is one if a series of publications which provides statistics on the foreign and domestic waterborne commerce moved on the United States waters. WCUS, parts 1-4 present detailed data on the moveme...
Global modelling of Cryptosporidium in surface water
NASA Astrophysics Data System (ADS)
Vermeulen, Lucie; Hofstra, Nynke
2016-04-01
Introduction Waterborne pathogens that cause diarrhoea, such as Cryptosporidium, pose a health risk all over the world. In many regions quantitative information on pathogens in surface water is unavailable. Our main objective is to model Cryptosporidium concentrations in surface waters worldwide. We present the GloWPa-Crypto model and use the model in a scenario analysis. A first exploration of global Cryptosporidium emissions to surface waters has been published by Hofstra et al. (2013). Further work has focused on modelling emissions of Cryptosporidium and Rotavirus to surface waters from human sources (Vermeulen et al 2015, Kiulia et al 2015). A global waterborne pathogen model can provide valuable insights by (1) providing quantitative information on pathogen levels in data-sparse regions, (2) identifying pathogen hotspots, (3) enabling future projections under global change scenarios and (4) supporting decision making. Material and Methods GloWPa-Crypto runs on a monthly time step and represents conditions for approximately the year 2010. The spatial resolution is a 0.5 x 0.5 degree latitude x longitude grid for the world. We use livestock maps (http://livestock.geo-wiki.org/) combined with literature estimates to calculate spatially explicit livestock Cryptosporidium emissions. For human Cryptosporidium emissions, we use UN population estimates, the WHO/UNICEF JMP sanitation country data and literature estimates of wastewater treatment. We combine our emissions model with a river routing model and data from the VIC hydrological model (http://vic.readthedocs.org/en/master/) to calculate concentrations in surface water. Cryptosporidium survival during transport depends on UV radiation and water temperature. We explore pathogen emissions and concentrations in 2050 with the new Shared Socio-economic Pathways (SSPs) 1 and 3. These scenarios describe plausible future trends in demographics, economic development and the degree of global integration. Results and Conclusions GloWPa-Crypto is the first global model that can be used to analyse dynamics in surface water pathogen concentrations worldwide. Global human Cryptosporidium emissions are estimated at 1 x 10^17 oocysts/ year for the year 2010.We estimated future emissions for SSP1 and SSP3. Preliminary results show that for SSP1human emissions are approximately halved by 2050. The SSP3 human emissions are 1.5 times higher than the 2010 emissions due to increased population growth and urbanisation. Livestock Cryptosporidium emissions are expected to increase under both SSP1 and SSP3, as meat consumption continues to rise. We conclude that population growth, urbanization, changes in sanitation systems and treatment, and changes in livestock consumption and production systems are important processes that determine future Cryptosporidium emissions to surface water. References Hofstra N, Bouwman A F, Beusen A H W and Medema G J 2013 Exploring global Cryptosporidium emissions to surface water Sci. Total Environ. 442 10-9 Kiulia N M, Hofstra N, Vermeulen L C, Obara M A, Medema G J and Rose J B 2015 Global occurrence and emission of rotaviruses to surface waters Pathogens 4 229-55 Vermeulen L C, De Kraker J, Hofstra N, Kroeze C and Medema G J 2015 Modelling the impact of sanitation, population and urbanization estimates on human emissions of Cryptosporidium to surface waters - a case study for Bangladesh and India Environ. Res. Lett. 10
Foodborne (1973-2013) and Waterborne (1971-2013) Disease Outbreaks - United States.
Dewey-Mattia, Daniel; Roberts, Virginia A; Vieira, Antonio; Fullerton, Kathleen E
2016-10-14
CDC collects data on foodborne and waterborne disease outbreaks reported by all U.S. states and territories through the Foodborne Disease Outbreak Surveillance System (FDOSS) (http://www.cdc.gov/foodsafety/fdoss/surveillance/index.html) and the Waterborne Disease and Outbreak Surveillance System (WBDOSS) http://www.cdc.gov/healthywater/surveillance), respectively. These two systems are the primary source of national data describing the number of reported outbreaks; outbreak-associated illnesses, hospitalizations, and deaths; etiologic agents; water source or implicated foods; settings of exposure; and other factors associated with recognized foodborne and waterborne disease outbreaks in the United States.
Scalable Emergency Response System for Oceangoing Assets Report on Defining Proposed Program
2008-10-17
electropherogram of RNA extracted from ocean water spiked with Salmonella sp ...meningoencephalitis Waterborne Balantidium coli Balantidosis (dysentery) Waterborne Cryptosporidium Cryptosporidiosis Waterborne Entamoeba histolytica Amoebic...extracted from ocean water spiked with Salmonella sp . The significance of bioanalyzer results lays in bands labeled as 23S rRNA in Figure 2 and 3. The
Mohammed, Asmaa N
2016-03-01
The hygienic quality of drinking water for cattle originated from different sources together with the efficacy and usability of two types of disinfectants against waterborne pathogens were assessed for small cattle breeders and dairy cattle farms. A total of 120 drinking water samples were collected from water troughs representing three different water sources commonly used for cattle drinking (tap, underground and surface water; n = 65, 25, and 30, respectively). Collected samples were cultured for isolation and identification of pathogenic bacteria using serological techniques and PCR. The bactericidal efficacy of the disinfectants, sodium dichloroisocyanurate (NaDCC) and hydrogen peroxide (H2O2) 50%, at different concentrations were evaluated by the determination of total viable and coliform counts of water prior and postwater treatment. In small cattle breeders, Escherichia coli was the most prevalent bacterial isolates from surface water (56.7%) followed by Staphylococcus aureus (36.7%), Salmonella spp. (26.7%), Streptococcus faecalis (23.3%), Shigella flexneri (16.7%), Proteus spp. (16.7%), and Klebsiella pneumonae (10.0 %) at X(2) = 9, P ≤ 0.01. Prior to the use of disinfectants, the averages of total bacterial and coliform counts were the highest in surface water (3.56 × 10(7), 240.0, and 38.0 CFU/100 ml, respectively). It has been found that hydrogen peroxide 50% at a concentration of 35 mg/l had a lethal effect (100 %) on indicator microorganisms compared with NaDCC at concentration of 2 mg/l. In conclusion, the higher bacterial contaminants in drinking water were found in surface water followed by tap water, particularly for small cattle breeders. Therefore, the usage of more hygienic water troughs with their regular treatment by hydrogen peroxide 50% at concentration of 35 mg/l is highly recommended to control waterborne bacteria and consequently improve and maintain the animal health.
Guzman Herrador, Bernardo R; de Blasio, Birgitte Freiesleben; MacDonald, Emily; Nichols, Gordon; Sudre, Bertrand; Vold, Line; Semenza, Jan C; Nygård, Karin
2015-03-27
Determining the role of weather in waterborne infections is a priority public health research issue as climate change is predicted to increase the frequency of extreme precipitation and temperature events. To document the current knowledge on this topic, we performed a literature review of analytical research studies that have combined epidemiological and meteorological data in order to analyze associations between extreme precipitation or temperature and waterborne disease.A search of the databases Ovid MEDLINE, EMBASE, SCOPUS and Web of Science was conducted, using search terms related to waterborne infections and precipitation or temperature. Results were limited to studies published in English between January 2001 and December 2013.Twenty-four articles were included in this review, predominantly from Asia and North-America. Four articles used waterborne outbreaks as study units, while the remaining articles used number of cases of waterborne infections. Results presented in the different articles were heterogeneous. Although most of the studies identified a positive association between increased precipitation or temperature and infection, there were several in which this association was not evidenced. A number of articles also identified an association between decreased precipitation and infections. This highlights the complex relationship between precipitation or temperature driven transmission and waterborne disease. We encourage researchers to conduct studies examining potential effect modifiers, such as the specific type of microorganism, geographical region, season, type of water supply, water source or water treatment, in order to assess how they modulate the relationship between heavy rain events or temperature and waterborne disease. Addressing these gaps is of primary importance in order to identify the areas where action is needed to minimize negative impact of climate change on health in the future.
Direct healthcare costs of selected diseases primarily or partially transmitted by water.
Collier, S A; Stockman, L J; Hicks, L A; Garrison, L E; Zhou, F J; Beach, M J
2012-11-01
Despite US sanitation advancements, millions of waterborne disease cases occur annually, although the precise burden of disease is not well quantified. Estimating the direct healthcare cost of specific infections would be useful in prioritizing waterborne disease prevention activities. Hospitalization and outpatient visit costs per case and total US hospitalization costs for ten waterborne diseases were calculated using large healthcare claims and hospital discharge databases. The five primarily waterborne diseases in this analysis (giardiasis, cryptosporidiosis, Legionnaires' disease, otitis externa, and non-tuberculous mycobacterial infection) were responsible for over 40 000 hospitalizations at a cost of $970 million per year, including at least $430 million in hospitalization costs for Medicaid and Medicare patients. An additional 50 000 hospitalizations for campylobacteriosis, salmonellosis, shigellosis, haemolytic uraemic syndrome, and toxoplasmosis cost $860 million annually ($390 million in payments for Medicaid and Medicare patients), a portion of which can be assumed to be due to waterborne transmission.
Direct healthcare costs of selected diseases primarily or partially transmitted by water
COLLIER, S. A.; STOCKMAN, L. J.; HICKS, L. A.; GARRISON, L. E.; ZHOU, F. J.; BEACH, M. J.
2015-01-01
SUMMARY Despite US sanitation advancements, millions of waterborne disease cases occur annually, although the precise burden of disease is not well quantified. Estimating the direct healthcare cost of specific infections would be useful in prioritizing waterborne disease prevention activities. Hospitalization and outpatient visit costs per case and total US hospitalization costs for ten waterborne diseases were calculated using large healthcare claims and hospital discharge databases. The five primarily waterborne diseases in this analysis (giardiasis, cryptosporidiosis, Legionnaires’ disease, otitis externa, and non-tuberculous mycobacterial infection) were responsible for over 40 000 hospitalizations at a cost of $970 million per year, including at least $430 million in hospitalization costs for Medicaid and Medicare patients. An additional 50 000 hospitalizations for campylobacteriosis, salmonellosis, shigellosis, haemolytic uraemic syndrome, and toxoplasmosis cost $860 million annually ($390 million in payments for Medicaid and Medicare patients), a portion of which can be assumed to be due to waterborne transmission. PMID:22233584
Effect of nitrogen-doped carbon dots on the anticorrosion properties of waterborne epoxy coatings
NASA Astrophysics Data System (ADS)
Ren, Siming; Cui, Mingjun; Zhao, Haichao; Wang, Liping
2018-06-01
In this work, nitrogen-doped carbon dots (NCDs) are prepared by solvothermal method and the effect of NCDs on the anticorrosion property of waterborne epoxy (EP) is investigated. Scanning probe microscopy results show that the size of the NCDs is about 4–6 nm. In addition, the anticorrosion property of NCD-incorporated waterborne epoxy coatings is investigated via electrochemical techniques and scanning electron microscopy. Electrochemical results demonstrate that the impedance modulus of 2.0% NCDs/EP is 364 times higher than that of blank EP after 800 h of immersion, indicating significant enhancement in the anticorrosion property of waterborne epoxy coating. The reason is that NCDs with lots of surface functional groups can connect with waterborne epoxy to suppress enlargement of the pores, and reduce the diffusion of oxygen in the coating, thus cutting off the connection between the substrate and oxygen, and delaying corrosion of the substrate.
Nsoh, Fuh Anold; Wung, Buh Amos; Atashili, Julius; Benjamin, Pokam Thumamo; Marvlyn, Eba; Ivo, Keumami Katte; Nguedia, Assob Jules Clément
2016-11-08
Access to potable water remains a major challenge particularly in resource-limited settings. Although the potential contaminants of water are varied, enteric pathogenic protozoa are known to cause waterborne diseases greatly. This study aimed at investigating the prevalence, characteristics and correlates of enteric pathogenic protozoa in drinking water sources in Buea, Cameroon. A cross-sectional study was conducted using 155 water samples collected from various drinking sources (boreholes, springs, taps and wells). Each sample was subjected to physicochemical examinations (pH, turbidity, odour and sliminess) and parasitological analysis (wet mount, modified Ziehl-Neelsen stain) to determine the presence of enteric pathogenic protozoa. A data collection tool was used to note characteristics of collected samples and the data was analysed using EPI-INFO Version 3.5.3. The overall prevalence of enteric pathogenic protozoa in water sources was 62.6 %. Eight species of enteric protozoa were observed with Cryptosporidium parvum being the most predominant (45.8 %). Spring water was the most contaminated source with enteric protozoa (85.7 %) while pipe borne water had all eight species of protozoa identified. A pH of 6 was the only significant factor associated with the prevalence of these pathogens in water sources. The prevalence of enteric protozoa in water sources in Molyko and Bomaka is high, spring water is the most contaminated water source and Cryptosporidium parvum is the most common protozoa contaminating water. A water pH of 6 is associated to the prevalence of protozoa. Community members need to be educated to treat water before drinking to avoid infection by enteric protozoa in water and further studies with larger samples of water need to be conducted to find other correlates of the presence of protozoa in water.
2011-01-01
Background It is well established that Legionella pneumophila is a waterborne pathogen; by contrast, the mode of Helicobacter pylori transmission remains unknown but water seems to play an important role. This work aims to study the influence of five microorganisms isolated from drinking water biofilms on the survival and integration of both of these pathogens into biofilms. Results Firstly, both pathogens were studied for auto- and co-aggregation with the species isolated from drinking water; subsequently the formation of mono and dual-species biofilms by L. pneumophila or H. pylori with the same microorganisms was investigated. Neither auto- nor co-aggregation was observed between the microorganisms tested. For biofilm studies, sessile cells were quantified in terms of total cells by SYTO 9 staining, viable L. pneumophila or H. pylori cells were quantified using 16 S rRNA-specific peptide nucleic acid (PNA) probes and cultivable cells by standard culture techniques. Acidovorax sp. and Sphingomonas sp. appeared to have an antagonistic effect on L. pneumophila cultivability but not on the viability (as assessed by rRNA content using the PNA probe), possibly leading to the formation of viable but noncultivable (VBNC) cells, whereas Mycobacterium chelonae increased the cultivability of this pathogen. The results obtained for H. pylori showed that M. chelonae and Sphingomonas sp. help this pathogen to maintain cultivability for at least 24 hours. Conclusions It appears that M. chelonae may have an important role in the survival of both pathogens in drinking water. This work also suggests that the presence of some microorganisms can decrease the cultivability of L. pneumophila but not the viability which indicates that the presence of autochthonous microorganisms can lead to misleading results when the safety of water is assessed by cultivable methods alone. PMID:21418578
NASA Astrophysics Data System (ADS)
Ward, Ray; Purnell, Sarah; Ebdon, James; Nnane, Daniel; Taylor, Huw
2013-04-01
The Water Framework Directive (WFD) regulates surface water quality standards in the European Union (EU). The Directive call for the identification and management of point and diffuse sources of pollution and requires the establishment of a 'programme of measures' for identified river basin districts, in order to achieve a "good status" by 2015. The hygienic quality of water is normally monitored using faecal indicator organisms (FIO), such as Escherichia coli, which indicate a potential risk to public health from human waterborne pathogens. Environmental factors influence the transmission of these pathogens and indicator organisms, and statistically significant relationships have been found between rainfall and outbreaks of waterborne disease. Climate change has been predicted to lead to an increase in severe weather events in many parts of Europe, including an increase in the frequency of extreme rainfall events. This in turn is likely to lead to an increase in incidents of human waterborne disease in Europe, unless measures are taken to predict and mitigate for such events. This study investigates a variety of environmental factors that influence the concentration of FIO in surface waters receiving faecal contamination from a variety of sources. Levels of FIO, including Escherichia coli, intestinal enterococci, somatic coliphage and GB124 (a human-specific microbial source tracking marker), were monitored in the Sussex Ouse catchment in Southeast England over a period of 26 months. These data were combined with geoinformatic environmental data within a GIS to map faecal contamination within the river. Previously, precipitation and soil erosion have been identified as major factors that can influence the concentration of these faecal markers, and studies have shown that slope, soil type and vegetation influence both the mechanisms and the rate by which erosion occurs in river catchments. Of the environmental variables studied, extreme precipitation was found to be a major factor contributing to increased levels of FIO. This study identifies areas within the catchment that are likely to demonstrate elevated erosion rates during extreme precipitation events, which are likely to result in raised levels of FIO. The results also demonstrate that increases in the human faecal marker were associated with the discharge points of wastewater treatment works, and that levels of the marker increased whenever the works discharged untreated wastewaters during extreme precipitation. Spatial analysis also highlighted locations where human faecal pollution was present in areas away from wastewater treatment plants, highlighting the potential significance of inputs from septic tanks and other un-sewered domestic wastewater systems. Increases in the frequency of extreme precipitation events in many parts of Europe are likely to result in increased levels of water pollution from both point- and diffuse-sources, increasing the input of pathogens into surface waters, and elevating the health risks to downstream consumers of abstracted drinking water. This study suggests an approach that integrates water microbiology and geoinformatic data to support a 'prediction and prevention' approach, in place of the traditional focus on water quality monitoring. This work may therefore make a significant contribution to future European water resource management and health protection.
Worley, Jay N; Flores, Kristopher A; Yang, Xun; Chase, Jennifer A; Cao, Guojie; Tang, Shuai; Meng, Jianghong; Atwill, Edward R
2017-08-15
Escherichia coli serotype O157:H7 is a zoonotic food- and waterborne bacterial pathogen that causes a high hospitalization rate and can cause life-threatening complications. Increasingly, E. coli O157:H7 infections appear to originate from fresh produce. Ruminants, such as cattle, are a prominent reservoir of E. coli O157:H7 in the United States. California is one of the most agriculturally productive regions in the world for fresh produce, beef, and milk. The close proximity of fresh produce and cattle presents food safety challenges on a uniquely large scale. We performed a survey of E. coli O157:H7 on 20 farms in California to observe the regional diversity and prevalence of E. coli O157:H7. Isolates were obtained from enrichment cultures of cow feces. Some farms were sampled on two dates. Genomes from isolates were sequenced to determine their relatedness and pathogenic potential. E. coli O157:H7 was isolated from approximately half of the farms. The point prevalence of E. coli O157:H7 on farms was highly variable, ranging from zero to nearly 90%. Within farms, generally one or a few lineages were found, even when the rate of isolation was high. On farms with high isolation rates, a single clonal lineage accounted for most of the isolates. Farms that were visited months after the first visit might have had the same lineages of E. coli O157:H7. Strains of E. coli O157:H7 may be persistent for months on farms. IMPORTANCE This survey of 20 cow-calf operations from different regions of California provides an in depth look at resident Escherichia coli O157:H7 populations at the molecular level. E. coli O157:H7 is found to have a highly variable prevalence, and with whole-genome sequencing, high prevalences in herds were found to be due to a single lineage shed from multiple cows. Few repeat lineages were found between farms in this area; therefore, we predict that E. coli O157:H7 has significant diversity in this area beyond what is detected in this survey. All isolates from this study were found to have pathogenic potential based on the presence of key virulence gene sequences. This represents a novel insight into pathogen diversity within a single subtype and will inform future attempts to survey regional pathogen populations. Copyright © 2017 American Society for Microbiology.
Worley, Jay N.; Flores, Kristopher A.; Yang, Xun; Chase, Jennifer A.; Cao, Guojie; Tang, Shuai; Meng, Jianghong
2017-01-01
ABSTRACT Escherichia coli serotype O157:H7 is a zoonotic food- and waterborne bacterial pathogen that causes a high hospitalization rate and can cause life-threatening complications. Increasingly, E. coli O157:H7 infections appear to originate from fresh produce. Ruminants, such as cattle, are a prominent reservoir of E. coli O157:H7 in the United States. California is one of the most agriculturally productive regions in the world for fresh produce, beef, and milk. The close proximity of fresh produce and cattle presents food safety challenges on a uniquely large scale. We performed a survey of E. coli O157:H7 on 20 farms in California to observe the regional diversity and prevalence of E. coli O157:H7. Isolates were obtained from enrichment cultures of cow feces. Some farms were sampled on two dates. Genomes from isolates were sequenced to determine their relatedness and pathogenic potential. E. coli O157:H7 was isolated from approximately half of the farms. The point prevalence of E. coli O157:H7 on farms was highly variable, ranging from zero to nearly 90%. Within farms, generally one or a few lineages were found, even when the rate of isolation was high. On farms with high isolation rates, a single clonal lineage accounted for most of the isolates. Farms that were visited months after the first visit might have had the same lineages of E. coli O157:H7. Strains of E. coli O157:H7 may be persistent for months on farms. IMPORTANCE This survey of 20 cow-calf operations from different regions of California provides an in depth look at resident Escherichia coli O157:H7 populations at the molecular level. E. coli O157:H7 is found to have a highly variable prevalence, and with whole-genome sequencing, high prevalences in herds were found to be due to a single lineage shed from multiple cows. Few repeat lineages were found between farms in this area; therefore, we predict that E. coli O157:H7 has significant diversity in this area beyond what is detected in this survey. All isolates from this study were found to have pathogenic potential based on the presence of key virulence gene sequences. This represents a novel insight into pathogen diversity within a single subtype and will inform future attempts to survey regional pathogen populations. PMID:28550057
M. A. Tshabalala; C. Starr; N. R. Sutherland
2010-01-01
In this study, wood specimens were coated with water-borne silsesquioxane oligomers by an in situ sol-gel deposition process. The effect of these water-borne sol-gel thin films on weathering characteristics and moisture-uptake properties of the wood specimens were investigated. The weathering characteristics were investigated by exposure of the specimens to artificial...
Zacheus, Outi; Miettinen, Ilkka T
2011-12-01
In 1997, a compulsory notification system for waterborne outbreaks was introduced in Finland. The main aim of this notification is to obtain immediate information on suspected waterborne outbreaks in order to restrict and manage the outbreak promptly. During the past ten years, there have been 67 waterborne outbreaks in Finland, mainly associated with small groundwater supplies or private wells. The number of reported waterborne outbreaks has increased since the launch of the notification system indicating that the threshold limit of outbreak detection has most probably decreased. The number of cases of illness has fulfilled the national health target, which is below 0.01% of the population, but more action is still needed to ensure the production of safe drinking water under all circumstances. Ten years accumulation of knowledge on outbreaks has revealed that a compulsory notification system is an effective tool to gather information on waterborne outbreaks. The system has also increased awareness of possible problems related to the quality of drinking water. This article summarises management and legislative actions and policy measures taken so far in Finland to reduce the number of outbreaks and cases of illness related to them.
NASA Astrophysics Data System (ADS)
Singh, Gulshan; Manohar, Murli; Adegoke, Anthony Ayodeji; Stenström, Thor Axel; Shanker, Rishi
2017-01-01
The lack of microbiologically safe water in underdeveloped nations is the prime cause of infectious disease outbreaks. The need for the specific identification and detection of microorganisms encourages the development of advanced, rapid, sensitive and highly specific methods for the monitoring of pathogens and management of potential risk to human health. The rapid molecular assays based on detection of specific molecular signatures offer advantages over conventional methods in terms of specificity and sensitivity but require complex instrumentation and skilled personnel. Nanotechnology is an emerging area and provides a robust approach for the identification of pathogenic microorganism utilizing the peculiar properties of nanomaterials, i.e. small size (1-100 nm) and large surface area. This emerging technology promises to fulfill the urgent need of a novel strategy to enhance the bacterial identification and quantitation in the environment. In this context, the peculiar properties of gold nanoparticles, their plasmonic shifts, and changes in magnetic properties have been utilized for the simple and cost-effective detection of bacterial nucleic acids, antigens and toxins with quite improved sensitivity. One of the promising leads to develop an advance detection method might be the coupling of nucleic acid aptamers (capable of interacting specifically with bacteria, protozoa, and viruses) with nanomaterials. Such aptamer-nano conjugate can be used for the specific recognition of infectious agents in different environmental matrices. This review summarizes the application of nanotechnology in the area of pathogen detection and discusses the prospects of coupling nucleic acid aptamers with nanoparticles for the specific detection of targeted pathogens.
Park, SungJun; Ko, Young-Seon; Jung, Haeyong; Lee, Cheonghoon; Woo, Kyoungja; Ko, GwangPyo
2018-06-01
Silver nanoparticles (AgNPs) have been reported as an effective alternative for controlling a broad-spectrum of pathogenic viruses. We developed a micrometer-sized silica hybrid composite decorated with AgNPs (AgNP-SiO 2 ) to prevent the inherent aggregation of AgNPs, and facilitated their recovery from environmental media after use. The production process had a high-yield, and fabrication was cost-effective. We evaluated the antiviral capabilities of Ag30-SiO 2 particles against two model viruses, bacteriophage MS2 and murine norovirus (MNV), in four different types of water (deionized, tap, surface, and ground). MNV was more susceptible to Ag30-SiO 2 particles in all four types of water compared to MS2. Furthermore, several water-related factors, including temperature and organic matter content, were shown to affect the antimicrobial capabilities of Ag30-SiO 2 particles. The modified Hom model was the best-fit disinfection model for MNV disinfection in the different types of water. Additionally, this study demonstrated that the effects of a certain level of physical obstacles in water were negligible in regards to the use of Ag30-SiO 2 particles. Thus, effective use of AgNPs in water disinfection processes can be achieved using our novel hybrid composites to inactivate various waterborne viruses. Copyright © 2018 Elsevier B.V. All rights reserved.
Gastroenteritis outbreak caused by waterborne norovirus at a New Zealand ski resort.
Hewitt, Joanne; Bell, Derek; Simmons, Greg C; Rivera-Aban, Malet; Wolf, Sandro; Greening, Gail E
2007-12-01
In July 2006, public health services investigated an outbreak of acute gastroenteritis among staff and visitors of a popular ski resort in southern New Zealand. The source of the outbreak was a drinking water supply contaminated by human sewage. The virological component of the investigation played a major role in confirming the source of the outbreak. Drinking water, source stream water, and 31 fecal specimens from gastroenteritis outbreak cases were analyzed for the presence of norovirus (NoV). Water samples were concentrated by ultrafiltration, and real-time reverse transcription-PCR (RT-PCR) was used for rapid detection of NoV from both water and fecal samples. The implicated NoV strain was further characterized by DNA sequencing. NoV genogroup GI/5 was identified in water samples and linked case fecal specimens, providing clear evidence of the predominant pathogen and route of exposure. A retrospective cohort study demonstrated that staff who consumed drinking water from the resort supply were twice as likely to have gastroenteritis than those who did not. This is the first time that an outbreak of gastroenteritis in New Zealand has been conclusively linked to NoV detected in a community water supply. To our knowledge, this is the first report of the use of ultrafiltration combined with quantitative real-time RT-PCR and DNA sequencing for investigation of a waterborne NoV outbreak.
Gómez-Couso, H; Fontán-Sainz, M; Navntoft, C; Fernández-Ibáñez, P; Ares-Mazás, E
2012-11-01
Solar water disinfection (SODIS) is a type of treatment that can significantly improve the microbiological quality of drinking water at household level and therefore prevent waterborne diseases in developing countries. Cryptosporidium parvum is an obligate protozoan parasite responsible for the diarrhoeal disease cryptosporidiosis in humans and animals. Recently, this parasite has been selected by the WHO as a reference pathogen for protozoan parasites in the evaluation of household water treatment options. In this study, the field efficacy of different static solar reactors [1.5 l transparent plastic polyethylene terephthalate (PET) bottles as well as 2.5 l borosilicate glass and 25 l methacrylate reactors fitted with compound parabolic concentrators (CPC)] for solar disinfection of turbid waters experimentally contaminated with C. parvum oocysts was compared. Potential oocyst viability was determined by inclusion/exclusion of the fluorogenic vital dye propidium iodide. The results demonstrate that static solar reactors fitted with CPCs are an excellent alternative to the conventional SODIS method with PET bottles. These reactors improved the efficacy of the SODIS method by enabling larger volumes of water to be treated and, in some cases, the C. parvum oocysts were rendered totally unviable, minimising the negative effects of turbidity. Copyright © 2012 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.
Evaluation of riverbank infiltration as a process for removing particles and DBP precursors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, J.; Smith, J.; Dooley, L.
1996-11-01
Recent outbreaks of waterborne disease attributed to Cryptosporidium in drinking water have raised serious concerns over the effectiveness of conventional water treatment processes to produce safe drinking water supplies. Past studies have shown Cryptosporidium and Giardia to be prevalent in surface water supplies, particularly in urban-impacted surface waters such as the Ohio River which Louisville Water Company (LWC) treatment facilities utilize as their source water. Such indications of the widespread occurrence of these pathogens in source waters underscore the need for the water supply industry to evaluate alternative technologies to conventional water treatment to reduce the risk of waterborne diseasemore » occurrence. Public health concerns, shared by the water utility industry, drinking water regulators, and public water supply consumers alike, prompted the US Environmental Protection Agency (USEPA) to propose regulatory action aimed at balancing the risks of microbial disease occurrence and the health risks associated with exposure to potentially harmful compounds formed during drinking water disinfection. In pursuit of this objective, USEPA proposed the Enhanced Surface Water Treatment Rule (ESWTR) to improve public water supply treatment performance for microbial removal and proposed the Disinfectant/Disinfection Byproduct (D/DBP) Rule to reduce DBP exposure levels. As a consequence of these rules, many water utilities will be tasked with the challenge of developing treatment capabilities which improve microbial removal performance while minimizing the production of DBPs.« less
Englehardt, James D; Ashbolt, Nicholas J; Loewenstine, Chad; Gadzinski, Erik R; Ayenu-Prah, Albert Y
2012-06-01
Recently pathogen counts in drinking and source waters were shown theoretically to have the discrete Weibull (DW) or closely related discrete growth distribution (DGD). The result was demonstrated versus nine short-term and three simulated long-term water quality datasets. These distributions are highly skewed such that available datasets seldom represent the rare but important high-count events, making estimation of the long-term mean difficult. In the current work the methods, and data record length, required to assess long-term mean microbial count were evaluated by simulation of representative DW and DGD waterborne pathogen count distributions. Also, microbial count data were analyzed spectrally for correlation and cycles. In general, longer data records were required for more highly skewed distributions, conceptually associated with more highly treated water. In particular, 500-1,000 random samples were required for reliable assessment of the population mean ±10%, though 50-100 samples produced an estimate within one log (45%) below. A simple correlated first order model was shown to produce count series with 1/f signal, and such periodicity over many scales was shown in empirical microbial count data, for consideration in sampling. A tiered management strategy is recommended, including a plan for rapid response to unusual levels of routinely-monitored water quality indicators.
A Customized DNA Microarray for Microbial Source Tracking ...
It is estimated that more than 160, 000 miles of rivers and streams in the United States are impaired due to the presence of waterborne pathogens. These pathogens typically originate from human and other animal fecal pollution sources; therefore, a rapid microbial source tracking (MST) method is needed to facilitate water quality assessment and impaired water remediation. We report a novel qualitative DNA microarray technology consisting of 453 probes for the detection of general fecal and host-associated bacteria, viruses, antibiotic resistance, and other environmentally relevant genetic indicators. A novel data normalization and reduction approach is also presented to help alleviate false positives often associated with high-density microarray applications. To evaluate the performance of the approach, DNA and cDNA was isolated from swine, cattle, duck, goose and gull fecal reference samples, as well as soiled poultry liter and raw municipal sewage. Based on nonmetric multidimensional scaling analysis of results, findings suggest that the novel microarray approach may be useful for pathogen detection and identification of fecal contamination in recreational waters. The ability to simultaneously detect a large collection of environmentally important genetic indicators in a single test has the potential to provide water quality managers with a wide range of information in a short period of time. Future research is warranted to measure microarray performance i
Microbiological monitoring for the US Geological Survey National Water-Quality Assessment Program
Francy, Donna S.; Myers, Donna N.; Helsel, Dennis R.
2000-01-01
Data to characterize the microbiological quality of the Nation?s fresh, marine, and estuarine waters are usually collected for local purposes, most often to judge compliance with standards for protection of public health in swimmable or drinkable waters. Methods and procedures vary with the objectives and practices of the parties collecting data and are continuously being developed or modified. Therefore, it is difficult to provide a nationally consistent picture of the microbial quality of the Nation?s waters. Study objectives and guidelines for a national microbiological monitoring program are outlined in this report, using the framework of the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) program. A national program is designed to provide long-term data on the presence of microbiological pathogens and indicators in ground water and surface water to support effective water policy and management. Three major groups of waterborne pathogens affect the public health acceptability of waters in the United States?bacteria, protozoa, and viruses. Microbiological monitoring in NAWQA would be designed to assess the occurrence, distribution, and trends of pathogenic organisms and indicators in surface waters and ground waters; relate the patterns discerned to factors that help explain them; and improve our understanding of the processes that control microbiological water quality.
Emerging bacterial pathogens: the past and beyond.
Vouga, M; Greub, G
2016-01-01
Since the 1950s, medical communities have been facing with emerging and reemerging infectious diseases, and emerging pathogens are now considered to be a major microbiologic public health threat. In this review, we focus on bacterial emerging diseases and explore factors involved in their emergence as well as future challenges. We identified 26 major emerging and reemerging infectious diseases of bacterial origin; most of them originated either from an animal and are considered to be zoonoses or from water sources. Major contributing factors in the emergence of these bacterial infections are: (1) development of new diagnostic tools, such as improvements in culture methods, development of molecular techniques and implementation of mass spectrometry in microbiology; (2) increase in human exposure to bacterial pathogens as a result of sociodemographic and environmental changes; and (3) emergence of more virulent bacterial strains and opportunistic infections, especially affecting immunocompromised populations. A precise definition of their implications in human disease is challenging and requires the comprehensive integration of microbiological, clinical and epidemiologic aspects as well as the use of experimental models. It is now urgent to allocate financial resources to gather international data to provide a better understanding of the clinical relevance of these waterborne and zoonotic emerging diseases. Copyright © 2015. Published by Elsevier Ltd.
Abdel-Nour, Mena; Duncan, Carla; Prashar, Akriti; Rao, Chitong; Ginevra, Christophe; Jarraud, Sophie; Low, Donald E.; Ensminger, Alexander W.; Terebiznik, Mauricio R.
2014-01-01
Although only partially understood, multicellular behavior is relatively common in bacterial pathogens. Bacterial aggregates can resist various host defenses and colonize their environment more efficiently than planktonic cells. For the waterborne pathogen Legionella pneumophila, little is known about the roles of autoaggregation or the parameters which allow cell-cell interactions to occur. Here, we determined the endogenous and exogenous factors sufficient to allow autoaggregation to take place in L. pneumophila. We show that isolates from Legionella species which do not produce the Legionella collagen-like protein (Lcl) are deficient in autoaggregation. Targeted deletion of the Lcl-encoding gene (lpg2644) and the addition of Lcl ligands impair the autoaggregation of L. pneumophila. In addition, Lcl-induced autoaggregation requires divalent cations. Escherichia coli producing surface-exposed Lcl is able to autoaggregate and shows increased biofilm production. We also demonstrate that L. pneumophila infection of Acanthamoeba castellanii and Hartmanella vermiformis is potentiated under conditions which promote Lcl dependent autoaggregation. Overall, this study shows that L. pneumophila is capable of autoaggregating in a process that is mediated by Lcl in a divalent-cation-dependent manner. It also reveals that Lcl potentiates the ability of L. pneumophila to come in contact, attach, and infect amoebae. PMID:24334670
DEVELOPMENT OF A MOLECULAR METHOD TO IDENTIFY ...
Hepatitis E virus (HEV) is an emerging pathogen that causes significant illness in the developing world. Like the hepatitis A virus, it is transmitted via the fecal-oral route and can cause short-term, acute hepatitis. In addition, hepatitis E has been found to cause a significant rate of mortality in pregnant women. Thus far, a hepatitis E outbreak has not been reported in the U. S. although a swine variant of the virus is common in Midwestern hogs. Since it will be important to identify the presence of this virus in the water supply, we have developed and are testing a reverse transcription-polymerase chain reaction (RT-PCR) method that should be able to identify all of the known HEV strains. Develop sensitive techniques to detect and identify emerging human waterborne pathogenic viruses and viruses on the CCL.Determine effectiveness of viral indicators to measure microbial quality in water matrices.Support activities: (a) culture and distribution of mammalian cells for Agency and scientific community research needs, (b) provide operator expertise for research requiring confocal and electron microscopy, (c) glassware cleaning, sterilization and biological waste disposal for the Cincinnati EPA facility, (d) operation of infectious pathogenic suite, (e) maintenance of walk-in constant temperature rooms and (f) provide Giardia cysts.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stegeman, J.; Smolowitz, R.; Burnett, K.
1994-12-31
Identifying target cells and organs is critical to establishing the sites and mechanisms of toxicity of Ah-receptor agonists. Previous studies have described the localization of CYPLA induced in multiple organs of fish exposed to Ah-receptor agonists. Here the authors compare the responses in multiple cell types and organs of small fish (Rivulus) exposed to waterborne TCDD. Adult fish were exposed to TCDD at concentrations from 0.01 to 10 ng/liter for 48 hours, then prepared and analyzed by immunohistochemistry with monoclonal antibody to teleost CYPIAI. At the highest dose profound induction was detected in virtually every organ. Structures staining intensely were:more » nasal and cephalic chemoreceptors, including sensory and basal cells; superficial cells in skin and pharynx; cartilage cells (chondrocytes) in the head, gills, growth plates and fins; epithelial and endothelial cells of liver, gut, kidney, and gill; pseudobranch vessels and glandular cells; eye lens epithelium; endothelium in vessels of eye, brain, skin, muscle, thymus and gonad. Lesser concentrations of TCDD elicited less strong responses, and control fish showed mild staining only in cartilage structures. The dose-dependent patterns of induction differed between different cell types. Responsive cells identified is these fish indicate sites where toxicity associated with Ah-receptor agonists or with CYPLA function may be expressed.« less
Neglected waterborne parasitic protozoa and their detection in water.
Plutzer, Judit; Karanis, Panagiotis
2016-09-15
Outbreak incidents raise the question of whether the less frequent aetiological agents of outbreaks are really less frequent in water. Alternatively, waterborne transmission could be relevant, but the lack of attention and rapid, sensitive methods to recover and detect the exogenous stages in water may keep them under-recognized. High quality information on the prevalence and detection of less frequent waterborne protozoa, such as Cyclospora cayetanensis, Toxoplasma gondii, Isospora belli, Balantidium coli, Blastocystis hominis, Entamoeba histolytica and other free-living amoebae (FLA), are not available. This present paper discusses the detection tools applied for the water surveillance of the neglected waterborne protozoa mentioned above and provides future perspectives. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Ceylan Koydemir, Hatice; Feng, Steve; Liang, Kyle; Nadkarni, Rohan; Tseng, Derek; Benien, Parul; Ozcan, Aydogan
2017-03-01
Giardia lamblia causes a disease known as giardiasis, which results in diarrhea, abdominal cramps, and bloating. Although conventional pathogen detection methods used in water analysis laboratories offer high sensitivity and specificity, they are time consuming, and need experts to operate bulky equipment and analyze the samples. Here we present a field-portable and cost-effective smartphone-based waterborne pathogen detection platform that can automatically classify Giardia cysts using machine learning. Our platform enables the detection and quantification of Giardia cysts in one hour, including sample collection, labeling, filtration, and automated counting steps. We evaluated the performance of three prototypes using Giardia-spiked water samples from different sources (e.g., reagent-grade, tap, non-potable, and pond water samples). We populated a training database with >30,000 cysts and estimated our detection sensitivity and specificity using 20 different classifier models, including decision trees, nearest neighbor classifiers, support vector machines (SVMs), and ensemble classifiers, and compared their speed of training and classification, as well as predicted accuracies. Among them, cubic SVM, medium Gaussian SVM, and bagged-trees were the most promising classifier types with accuracies of 94.1%, 94.2%, and 95%, respectively; we selected the latter as our preferred classifier for the detection and enumeration of Giardia cysts that are imaged using our mobile-phone fluorescence microscope. Without the need for any experts or microbiologists, this field-portable pathogen detection platform can present a useful tool for water quality monitoring in resource-limited-settings.
A neighborhood statistics model for predicting stream pathogen indicator levels.
Pandey, Pramod K; Pasternack, Gregory B; Majumder, Mahbubul; Soupir, Michelle L; Kaiser, Mark S
2015-03-01
Because elevated levels of water-borne Escherichia coli in streams are a leading cause of water quality impairments in the U.S., water-quality managers need tools for predicting aqueous E. coli levels. Presently, E. coli levels may be predicted using complex mechanistic models that have a high degree of unchecked uncertainty or simpler statistical models. To assess spatio-temporal patterns of instream E. coli levels, herein we measured E. coli, a pathogen indicator, at 16 sites (at four different times) within the Squaw Creek watershed, Iowa, and subsequently, the Markov Random Field model was exploited to develop a neighborhood statistics model for predicting instream E. coli levels. Two observed covariates, local water temperature (degrees Celsius) and mean cross-sectional depth (meters), were used as inputs to the model. Predictions of E. coli levels in the water column were compared with independent observational data collected from 16 in-stream locations. The results revealed that spatio-temporal averages of predicted and observed E. coli levels were extremely close. Approximately 66 % of individual predicted E. coli concentrations were within a factor of 2 of the observed values. In only one event, the difference between prediction and observation was beyond one order of magnitude. The mean of all predicted values at 16 locations was approximately 1 % higher than the mean of the observed values. The approach presented here will be useful while assessing instream contaminations such as pathogen/pathogen indicator levels at the watershed scale.
Hogan, Jennifer N.; Daniels, Miles E.; Watson, Fred G.; Conrad, Patricia A.; Oates, Stori C.; Miller, Melissa A.; Hardin, Dane; Byrne, Barbara A.; Dominik, Clare; Melli, Ann; Jessup, David A.
2012-01-01
Fecal pathogen contamination of watersheds worldwide is increasingly recognized, and natural wetlands may have an important role in mitigating fecal pathogen pollution flowing downstream. Given that waterborne protozoa, such as Cryptosporidium and Giardia, are transported within surface waters, this study evaluated associations between fecal protozoa and various wetland-specific and environmental risk factors. This study focused on three distinct coastal California wetlands: (i) a tidally influenced slough bordered by urban and agricultural areas, (ii) a seasonal wetland adjacent to a dairy, and (iii) a constructed wetland that receives agricultural runoff. Wetland type, seasonality, rainfall, and various water quality parameters were evaluated using longitudinal Poisson regression to model effects on concentrations of protozoa and indicator bacteria (Escherichia coli and total coliform). Among wetland types, the dairy wetland exhibited the highest protozoal and bacterial concentrations, and despite significant reductions in microbe concentrations, the wetland could still be seen to influence water quality in the downstream tidal wetland. Additionally, recent rainfall events were associated with higher protozoal and bacterial counts in wetland water samples across all wetland types. Notably, detection of E. coli concentrations greater than a 400 most probable number (MPN) per 100 ml was associated with higher Cryptosporidium oocyst and Giardia cyst concentrations. These findings show that natural wetlands draining agricultural and livestock operation runoff into human-utilized waterways should be considered potential sources of pathogens and that wetlands can be instrumental in reducing pathogen loads to downstream waters. PMID:22427504
Pathogenic waterborne free-living amoebae: An update from selected Southeast Asian countries
Abdul Majid, Mohamad Azlan; Mahboob, Tooba; Mong, Brandon G. J.; Jaturas, Narong; Richard, Reena Leeba; Tian-Chye, Tan; Phimphila, Anusorn; Mahaphonh, Panomphanh; Aye, Kyaw Nyein; Aung, Wai Lynn; Chuah, Joon; Ziegler, Alan D.; Yasiri, Atipat; Sawangjaroen, Nongyao; Lim, Yvonne A. L.; Nissapatorn, Veeranoot
2017-01-01
Data on the distribution of free-living amoebae is still lacking especially in Southeast Asian region. The aquatic environment revealed a high occurrence of free-living amoebae (FLA) due to its suitable condition and availability of food source, which subsequently causes infection to humans. A total of 94 water samples consisted of both treated and untreated from Laos (31), Myanmar (42), and Singapore (21) were investigated for the presence of pathogenic FLA. Each water sample was filtered and cultured onto non-nutrient agar seeded with live suspension of Escherichia coli and incubated at room temperature. Morphological identification was conducted for both trophozoites and cysts via microscopic stains (Giemsa and immunofluorescence). The presence of Naegleria-like structures was the most frequently encountered in both treated and untreated water samples, followed by Acanthamoeba-like and Vermamoeba-like features. To identify the pathogenic isolates, species-specific primer sets were applied for molecular identification of Acanthamoeba, Naegleria, and Vermamoeba. The pathogenic species of Acanthamoeba lenticulata and A. triangularis were detected from untreated water samples, while Vermamoeba vermiformis was found in both treated and untreated water samples. Our results suggested that poor water quality as well as inadequate maintenance and treatment might be the cause of this alarming problem since chlorine disinfection is ineffective in eradicating these amoebas in treated water samples. Regular monitoring and examination of water qualities are necessary in order to control the growth, hence, further preventing the widespread of FLA infections among the public. PMID:28212409
Pathogenic waterborne free-living amoebae: An update from selected Southeast Asian countries.
Abdul Majid, Mohamad Azlan; Mahboob, Tooba; Mong, Brandon G J; Jaturas, Narong; Richard, Reena Leeba; Tian-Chye, Tan; Phimphila, Anusorn; Mahaphonh, Panomphanh; Aye, Kyaw Nyein; Aung, Wai Lynn; Chuah, Joon; Ziegler, Alan D; Yasiri, Atipat; Sawangjaroen, Nongyao; Lim, Yvonne A L; Nissapatorn, Veeranoot
2017-01-01
Data on the distribution of free-living amoebae is still lacking especially in Southeast Asian region. The aquatic environment revealed a high occurrence of free-living amoebae (FLA) due to its suitable condition and availability of food source, which subsequently causes infection to humans. A total of 94 water samples consisted of both treated and untreated from Laos (31), Myanmar (42), and Singapore (21) were investigated for the presence of pathogenic FLA. Each water sample was filtered and cultured onto non-nutrient agar seeded with live suspension of Escherichia coli and incubated at room temperature. Morphological identification was conducted for both trophozoites and cysts via microscopic stains (Giemsa and immunofluorescence). The presence of Naegleria-like structures was the most frequently encountered in both treated and untreated water samples, followed by Acanthamoeba-like and Vermamoeba-like features. To identify the pathogenic isolates, species-specific primer sets were applied for molecular identification of Acanthamoeba, Naegleria, and Vermamoeba. The pathogenic species of Acanthamoeba lenticulata and A. triangularis were detected from untreated water samples, while Vermamoeba vermiformis was found in both treated and untreated water samples. Our results suggested that poor water quality as well as inadequate maintenance and treatment might be the cause of this alarming problem since chlorine disinfection is ineffective in eradicating these amoebas in treated water samples. Regular monitoring and examination of water qualities are necessary in order to control the growth, hence, further preventing the widespread of FLA infections among the public.
Daniels, Miles E; Hogan, Jennifer; Smith, Woutrina A; Oates, Stori C; Miller, Melissa A; Hardin, Dane; Shapiro, Karen; Los Huertos, Marc; Conrad, Patricia A; Dominik, Clare; Watson, Fred G R
2014-09-15
Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii are waterborne protozoal pathogens distributed worldwide and empirical evidence suggests that wetlands reduce the concentrations of these pathogens under certain environmental conditions. The goal of this study was to evaluate how protozoal removal in surface water is affected by the water temperature, turbidity, salinity, and vegetation cover of wetlands in the Monterey Bay region of California. To examine how protozoal removal was affected by these environmental factors, we conducted observational experiments at three primary spatial scales: settling columns, recirculating wetland mesocosm tanks, and an experimental research wetland (Molera Wetland). Simultaneously, we developed a protozoal transport model for surface water to simulate the settling columns, the mesocosm tanks, and the Molera Wetland. With a high degree of uncertainty expected in the model predictions and field observations, we developed the model within a Bayesian statistical framework. We found protozoal removal increased when water flowed through vegetation, and with higher levels of turbidity, salinity, and temperature. Protozoal removal in surface water was maximized (~0.1 hour(-1)) when flowing through emergent vegetation at 2% cover, and with a vegetation contact time of ~30 minutes compared to the effects of temperature, salinity, and turbidity. Our studies revealed that an increase in vegetated wetland area, with water moving through vegetation, would likely improve regional water quality through the reduction of fecal protozoal pathogen loads. Copyright © 2014 Elsevier B.V. All rights reserved.
Braeye, T; DE Schrijver, K; Wollants, E; van Ranst, M; Verhaegen, J
2015-03-01
SUMMARY On 6 December 2010 a fire in Hemiksem, Belgium, was extinguished by the fire brigade with both river water and tap water. Local physicians were asked to report all cases of gastroenteritis. We conducted a retrospective cohort study among 1000 randomly selected households. We performed a statistical and geospatial analysis. Human stool samples, tap water and river water were tested for pathogens. Of the 1185 persons living in the 528 responding households, 222 (18·7%) reported symptoms of gastroenteritis during the time period 6-13 December. Drinking tap water was significantly associated with an increased risk for gastroenteritis (relative risk 3·67, 95% confidence interval 2·86-4·70) as was place of residence. Campylobacter sp. (2/56), norovirus GI and GII (11/56), rotavirus (1/56) and Giardia lamblia (3/56) were detected in stool samples. Tap water samples tested positive for faecal indicator bacteria and protozoa. The results support the hypothesis that a point-source contamination of the tap water with river water was the cause of the multi-pathogen waterborne outbreak.
Dose-response algorithms for water-borne Pseudomonas aeruginosa folliculitis.
Roser, D J; Van Den Akker, B; Boase, S; Haas, C N; Ashbolt, N J; Rice, S A
2015-05-01
We developed two dose-response algorithms for P. aeruginosa pool folliculitis using bacterial and lesion density estimates, associated with undetectable, significant, and almost certain folliculitis. Literature data were fitted to Furumoto & Mickey's equations, developed for plant epidermis-invading pathogens: N l = A ln(1 + BC) (log-linear model); P inf = 1-e(-r c C) (exponential model), where A and B are 2.51644 × 107 lesions/m2 and 2.28011 × 10-11 c.f.u./ml P. aeruginosa, respectively; C = pathogen density (c.f.u./ml), N l = folliculitis lesions/m2, P inf = probability of infection, and r C = 4·3 × 10-7 c.f.u./ml P. aeruginosa. Outbreak data indicates these algorithms apply to exposure durations of 41 ± 25 min. Typical water quality benchmarks (≈10-2 c.f.u./ml) appear conservative but still useful as the literature indicated repeated detection likely implies unstable control barriers and bacterial bloom potential. In future, culture-based outbreak testing should be supplemented with quantitative polymerase chain reaction and organic carbon assays, and quantification of folliculitis aetiology to better understand P. aeruginosa risks.
Lee, Seung-Hyun; Joung, Migyo; Yoon, Sejoung; Choi, Kyoungjin; Park, Woo-Yoon; Yu, Jae-Ran
2010-12-01
Recently, emerging waterborne protozoa, such as microsporidia, Cyclospora, and Cryptosporidium, have become a challenge to human health worldwide. Rapid, simple, and economical detection methods for these major waterborne protozoa in environmental and clinical samples are necessary to control infection and improve public health. In the present study, we developed a multiplex PCR test that is able to detect all these 3 major waterborne protozoa at the same time. Detection limits of the multiplex PCR method ranged from 10(1) to 10(2) oocysts or spores. The primers for microsporidia or Cryptosporidium used in this study can detect both Enterocytozoon bieneusi and Encephalitozoon intestinalis, or both Cryptosporidium hominis and Cryptosporidium parvum, respectively. Restriction enzyme digestion of PCR products with BsaBI or BsiEI makes it possible to distinguish the 2 species of microsporidia or Cryptosporidium, respectively. This simple, rapid, and cost-effective multiplex PCR method will be useful for detecting outbreaks or sporadic cases of waterborne protozoa infections.
NASA Astrophysics Data System (ADS)
McBride, Graham; Slaney, David; Tait, Andrew
2013-04-01
The New Zealand health system has defined as 'notifiable' over 50 diseases. Of these campylobacteriosis is the most commonly reported comprising 41% of all notifications in 2011 (presently about 150 illness cases per 100,000 population per annum). Furthermore, the incidence of this mild illness, which is potentially waterborne, is under-reported by at least an order-of-magnitude. Increased downstream pathogen loads and/or disease incidence have been found to be associated with increased rainfall, particularly in agricultural landscapes. Therefore, given the predominance of agricultural land uses in New Zealand, transmission and exposure to its agent (thermotolerant Campylobacter bacteria) may be affected by changing rainfall and temperature patterns associated with climate change. Reporting rates for other potentially water-borne zoonoses are also noticeable (for example, the reported rate for cryptosporidiosis for 2011 was 14 per 100,000 population). The distribution of Cryptosporidium oocysts in the environment may be influenced by climate change because it has often been implicated in drinking-water contamination, and heavy rainfall events have been found to be associated with increased pathogen loads in rivers and disease incidence. Given this background, which may also be applicable to other countries with agriculturally-dominated landscapes, a New Zealand study was initiated to develop a decision-support system for the projected effects of climate change on a selected suite of environmentally-transmitted pathogens, including Campylobacter and Cryptosporodium oocysts. Herein we report on the manner in which a linear SIR (Susceptible-Ill-Recovered) model previously developed for campylobacteriosis can be extended to cryptosporidiosis, applied to changes in pathogen contact rate and hence reported illness, and coupled to climate change projections associated with different greenhouse gas emission scenarios. The resulting SIR model outputs provided projected changes in reported disease incidence as a function of temperature and rainfall. These models account for age-dependency (children versus adults), which is especially important because children can report substantially higher rates of zoonoses. The model is linear because the zoonotic pathogen 'reservoir' is overwhelmingly among animals, and so the usual interaction in which human-pathogen interactions affect the degree of environmental contamination does not apply in the short term (on the order of one year). Accordingly, the interaction can be approximated by a constant contact rate over a given year, even though the contact rates may vary between decades because of climate change and variability. This linearity property enables the derivation of analytical solutions to the model's governing equations, thereby providing for a more elegant examination of the model's properties and for making projections under climate change. The models have been calibrated to reported rates of these diseases. Simple exponential functions have been used to vary the pathogen contact rates for the reference years 2015, 2040 and 2090 under three climate change scenarios of low, medium and high emissions of greenhouse gases (B1, A1B, and A2). These formulations have been guided by the results of statistical models calibrated to historical disease reporting rates. The models have been used to calculate the ratio of reported illness rates to present rates projected for future years across New Zealand at the ~5 km scale. Detailed results will be presented for the reference year 2040.
Spatial Distribution and Trends of Waterborne Diseases in Tashkent Province
Subramanian, Veluswami Saravanan; Cho, Min Jung; Tan, Siwei Zoe; Fayzieva, Dilorom; Sebaly, Christian
2017-01-01
Introduction: The cumulative effect of limited investment in public water systems, inadequate public health infrastructure, and gaps in infectious disease prevention increased the incidence of waterborne diseases in Uzbekistan. The objectives of this study were: (1) to spatially analyze the distribution of the diseases in Tashkent Province, (2) to identify the intensity of spatial trends in the province, (3) to identify urban-rural characteristics of the disease distribution, and (4) to identify the differences in disease incidence between pediatric and adult populations of the province. Methods: Data on four major waterborne diseases and socio-demographics factors were collected in Tashkent Province from 2011 to 2014. Descriptive epidemiological methods and spatial-temporal methods were used to investigate the distribution and trends, and to identify waterborne diseases hotspots and vulnerable population groups in the province. Results: Hepatitis A and enterobiasis had a high incidence in most of Tashkent Province, with higher incidences in the eastern and western districts. Residents of rural areas, including children, were found to be more vulnerable to the waterborne diseases compared to other populations living in the province. Conclusions: This pilot study calls for more scientific investigations of waterborne diseases and their effect on public health in the region, which could facilitate targeted public health interventions in vulnerable regions of Uzbekistan. PMID:29138738
Spatial Distribution and Trends of Waterborne Diseases in Tashkent Province.
Subramanian, Veluswami Saravanan; Cho, Min Jung; Tan, Siwei Zoe; Fayzieva, Dilorom; Sebaly, Christian
2017-01-01
The cumulative effect of limited investment in public water systems, inadequate public health infrastructure, and gaps in infectious disease prevention increased the incidence of waterborne diseases in Uzbekistan. The objectives of this study were: (1) to spatially analyze the distribution of the diseases in Tashkent Province, (2) to identify the intensity of spatial trends in the province, (3) to identify urban-rural characteristics of the disease distribution, and (4) to identify the differences in disease incidence between pediatric and adult populations of the province. Data on four major waterborne diseases and socio-demographics factors were collected in Tashkent Province from 2011 to 2014. Descriptive epidemiological methods and spatial-temporal methods were used to investigate the distribution and trends, and to identify waterborne diseases hotspots and vulnerable population groups in the province. Hepatitis A and enterobiasis had a high incidence in most of Tashkent Province, with higher incidences in the eastern and western districts. Residents of rural areas, including children, were found to be more vulnerable to the waterborne diseases compared to other populations living in the province. This pilot study calls for more scientific investigations of waterborne diseases and their effect on public health in the region, which could facilitate targeted public health interventions in vulnerable regions of Uzbekistan.
Vulnerability of waterborne diseases to climate change in Canada: a review.
Charron, Dominique; Thomas, M; Waltner-Toews, David; Aramini, Jeffery; Edge, Tom; Kent, Robert; Maarouf, Abdel; Wilson, Jeff
This project addresses two important issues relevant to the health of Canadians: the risk of waterborne illness and the health impacts of global climate change. The Canadian health burden from waterborne illness is unknown, although it presumably accounts for a significant proportion of enteric illness. Recently, large outbreaks with severe consequences produced by E. coli O157:H7 and Cryptosporidium have alarmed Canadians and brought demands for political action. A concurrent need to understand the health impacts of global climate changes and to develop strategies to prevent or prepare for these has also been recognized. There is mounting evidence that weather is often a factor in triggering waterborne disease outbreaks. A recent study of precipitation and waterborne illness in the United States found that more than half the waterborne disease outbreaks in the United States during the last half century followed a period of extreme rainfall. Projections of international global climate change scenarios suggest that, under conditions of global warming most of Canada may expect longer summers, milder winters, increased summer drought, and more extreme precipitation. Excess precipitation, floods, high temperatures, and drought could affect the risk of waterborne illness in Canada. The existing scientific information regarding most weather-related adverse health impacts and on the impacts of global climate change on health in Canada is insufficient for informed decision making. The results of this project address this need through the investigation of the complex systemic interrelationships between disease incidence, weather parameters, and water quality and quantity, and by projecting the potential impact of global climate change on those relationships.
Gautam, Raju; Bani-Yaghoub, Majid; Neill, William H; Döpfer, Dörte; Kaspar, Charles; Ivanek, Renata
2011-10-01
To explore the potential role of ambient temperature on infection transmission dynamics for pathogens, we used Escherichia coli O157:H7 in a dairy herd and the surrounding farm environment as a model system. For this system, we developed a mathematical model in which a Susceptible-Infectious-Susceptible (SIS) model of infection spread through the host population is coupled with a metapopulation model of E. coli O157:H7 free-living stage in the environment allowing bacterial growth to be influenced by ambient temperature. Model results indicate that seasonal variation in ambient temperature could have a considerable impact on pathogen populations in the environment, specifically on barn surfaces and in water troughs, and consequently on the prevalence of infection in the host population. Based on model assumptions, contaminated drinking water was the most important pathway of E. coli O157:H7 transmission to cattle. Sensitivity analysis indicated that water-borne transmission is amplified during the warmer months if the amount of standing drinking water available to the cattle herd is high. This is because warmer ambient temperature favors faster pathogen replication which when combined with slower water replacement-rate due to high amount of available standing water leads to a greater pathogen load in drinking water. These results offer a possible explanation of the seasonal variation in E. coli O157:H7 prevalence in cattle and suggest that improved drinking-water management could be used for control of this infection in cattle. Our study demonstrates how consideration of ambient temperature in transmission cycles of pathogens able to survive and grow in the environment outside the host could offer novel perspectives on the spread and control of infections caused by such pathogens. Copyright © 2011 Elsevier B.V. All rights reserved.
Diallo, Mamadou B C; Anceno, Alfredo J; Tawatsupa, Benjawan; Tripathi, Nitin K; Wangsuphachart, Voranuch; Shipin, Oleg V
2009-03-01
Urban canals play a major socio-economic role in many tropical countries and, particularly, Thailand. One of the overlooked functions that they perform is a significant attenuation of waste-related pathogens posing considerable health risk, as well as pollution attenuation in general. The study dealt with a comparison of three canals receiving: (i) municipal, (ii) mainly industrial and (iii) mainly agricultural wastewater, listed in order of progressively decreasing organic loading. The occurrence and fate of waterborne Cryptosporidium parvum, Giardia lamblia and Escherichia coli were monitored in the canals by both real-time PCR and conventionally for 12 months. The pathogens are etiological agents of an estimated 38% and 47% of diarrhea cases worldwide and in Thailand, respectively. The geographic information system (GIS) was used to evaluate and map point and, particularly, non-point pollution sources which allowed differentiating the canal sections in terms of predominant pathogen sources. The flowthrough canals, which can be viewed as waste stabilization ponds, were found to be efficiently removing the pathogens at the following generalized specific rates: 0.3 (C. parvum), 1.2 (G. lamblia), 1.8 (E. coli) log10/km.d in the dry season. The rates decreased in the rainy season for E. coli and G. lamblia, but increased for C. parvum which indicated different removal mechanisms. Data suggest that E. coli and G. lamblia were mainly removed through sedimentation and sunlight (UV) irradiation, while the likely mechanism for C. parvum was predation. Overall, the specific pathogen removal rates positively correlated with the canal organic loading rates in the rainy season. As an important result, an estimate of the municipal pollution mitigation by over 2280 km canals in the Greater Bangkok suggests that concomitant to the pathogens at least 36-95 tons of BOD5 is being removed daily, thereby saving the receiving Chao Phraya River and Bight of Bangkok, by far exceeding current, from major eutrophication problems.
2018-01-01
Background In many low-income settings, despite improvements in sanitation and hygiene, groundwater sources used for drinking may be contaminated with enteric pathogens such as Cryptosporidium and Giardia, which remain important causes of childhood morbidity. In this study, we examined the contribution of diarrhea caused by Cryptosporidium and Giardia found in groundwater sources used for drinking to the total burden of diarrheal disease among children < 5 in rural India. Methodology/Principal findings We studied a population of 3,385 children < 5 years of age in 100 communities of Puri District, Odisha, India. We developed a coupled quantitative microbial risk assessment (QMRA) and susceptible-infected-recovered (SIR) population model based on observed levels of Cryptosporidium and Giardia in improved groundwater sources used for drinking and compared the QMRA-SIR estimates with independently measured all-cause (i.e., all fecal-oral enteric pathogens and exposure pathways) child diarrhea prevalence rates observed in the study population during two monsoon seasons (2012 and 2013). We used site specific and regional studies to inform assumptions about the human pathogenicity of the Cryptosporidium and Giardia species present in local groundwater. In all three human pathogenicity scenarios evaluated, the mean daily risk of Cryptosporidium or Giardia infection (0.06–1.53%), far exceeded the tolerable daily risk of infection from drinking water in the US (< 0.0001%). Depending on which protozoa species were present, median estimates of daily child diarrhea prevalence due to either Cryptosporidium or Giardia infection from drinking water was as high as 6.5% or as low as < 1% and accounted for at least 2.9% and as much as 65.8% of the all-cause diarrhea disease burden measured in children < 5 during the study period. Cryptosporidium tended to account for a greater share of estimated waterborne protozoa infections causing diarrhea than did Giardia. Diarrhea prevalence estimates for waterborne Cryptosporidium infection appeared to be most sensitive to assumptions about the probability of infection from ingesting a single parasite (i.e. the rate parameter in dose-response model), while Giardia infection was most sensitive to assumptions about the viability of parasites detected in groundwater samples. Conclusions/Significance Protozoa in groundwater drinking sources in rural India, even at low concentrations, especially for Cryptosporidium, may account for a significant portion of child diarrhea morbidity in settings were tubewells are used for drinking water and should be more systematically monitored. Preventing diarrheal disease burdens in Puri District and similar settings will benefit from ensuring water is microbiologically safe for consumption and consistent and effective household water treatment is practiced. PMID:29377884
Zilbermintz, Leeor; Leonardi, William; Jeong, Sun-Young; Sjodt, Megan; McComb, Ryan; Ho, Chi-Lee C; Retterer, Cary; Gharaibeh, Dima; Zamani, Rouzbeh; Soloveva, Veronica; Bavari, Sina; Levitin, Anastasia; West, Joel; Bradley, Kenneth A; Clubb, Robert T; Cohen, Stanley N; Gupta, Vivek; Martchenko, Mikhail
2015-08-27
A longstanding and still-increasing threat to the effective treatment of infectious diseases is resistance to antimicrobial countermeasures. Potentially, the targeting of host proteins and pathways essential for the detrimental effects of pathogens offers an approach that may discover broad-spectrum anti-pathogen countermeasures and circumvent the effects of pathogen mutations leading to resistance. Here we report implementation of a strategy for discovering broad-spectrum host-oriented therapies against multiple pathogenic agents by multiplex screening of drugs for protection against the detrimental effects of multiple pathogens, identification of host cell pathways inhibited by the drug, and screening for effects of the agent on other pathogens exploiting the same pathway. We show that a clinically used antimalarial drug, Amodiaquine, discovered by this strategy, protects host cells against infection by multiple toxins and viruses by inhibiting host cathepsin B. Our results reveal the practicality of discovering broadly acting anti-pathogen countermeasures that target host proteins exploited by pathogens.
Pereira, Rui P A; Peplies, Jörg; Höfle, Manfred G; Brettar, Ingrid
2017-10-01
Cooling towers are the major source of outbreaks of legionellosis in Europe and worldwide. These outbreaks are mostly associated with Legionella species, primarily L. pneumophila, and its surveillance in cooling tower environments is of high relevance to public health. In this study, a combined NGS-based approach was used to study the whole bacterial community, specific waterborne and water-based bacterial pathogens, especially Legionella species, targeting the 16S rRNA gene. This approach was applied to water from a cooling tower obtained by monthly sampling during two years. The studied cooling tower was an open circuit cooling tower with lamellar cooling situated in Braunschweig, Germany. A highly diverse bacterial community was observed with 808 genera including 25 potentially pathogenic taxa using universal 16S rRNA primers. Sphingomonas and Legionella were the most abundant pathogenic genera. By applying genus-specific primers for Legionella, a diverse community with 85 phylotypes, and a representative core community with substantial temporal heterogeneity was observed. A high percentage of sequences (65%) could not be affiliated to an acknowledged species. L. pneumophila was part of the core community and the most abundant Legionella species reinforcing the importance of cooling towers as its environmental reservoir. Major temperature shifts (>10 °C) were the key environmental factor triggering the reduction or dominance of the Legionella species in the Legionella community dynamics. In addition, interventions by chlorine dioxide had a strong impact on the Legionella community composition but not on the whole bacterial community. Overall, the presented results demonstrated the value of a combined NGS approach for the molecular monitoring and surveillance of health related pathogens in man-made freshwater systems. Copyright © 2017 Elsevier Ltd. All rights reserved.
Lin, Tzu-Chao; Wu, Rui-Xin; Chiu, Chih-Chien; Yang, Ya-Sung; Lee, Yi; Lin, Jung-Chung; Chang, Feng-Yee
2018-04-01
Bloodstream infection is a leading cause of mortality among burn patients. This study aimed to evaluate the risk factors, causative pathogens, and the relationship between bloodstream infections and other infections among burn patients from the Formosa Fun Coast Dust Explosion. This retrospective study evaluated the demographic and clinical characteristics, infection types, causative pathogen(s), and isolates' antibiotic susceptibilities from patients who were hospitalized between June 27 and September 31, 2015. Fifty-eight patients were admitted during the study period (36 males, mean age: 22.6 years). The mean burned total body surface area (TBSA) was 40% for all patients. Eighteen (31%) patients with mean TBSA of 80% had 66 episodes of bloodstream infections caused by 92 isolates. Twelve (18.2%) episodes of bloodstream infections were polymicrobial. Acinetobacter baumannii (19, 20.7%), Ralstonia pickettii (17, 18.5%), and Chryseobacterium meningosepticum (13, 14.1%) were the most common pathogens causing bloodstream infections. A high concordance rate of wound cultures with blood cultures was seen in Staphylococcus aureus (3, 75%) and C. meningosepticum (8, 61.5%) infections. However, no Ralstonia isolate was found in burn wounds of patients with Ralstonia bacteremia. A high concordance rate of central venous catheter cultures with blood cultures was noted in Ralstonia mannitolilytica (5, 62.5%) and Chryseobacterium indologenes (3, 60%) infections. Approximately 21.1% of A. baumannii strains were resistant to carbapenem. All S. aureus isolates were susceptible to methicillin. Waterborne bacteria should be considered in patients of burns with possible water contact. Empirical broad-spectrum antibiotics should be considered for patients who were hospitalized for severe sepsis, or septic shock with a large burn. Antibiotic treatment should be administered based on the specific pathogens and their detection points. Copyright © 2017. Published by Elsevier B.V.
1982-09-01
PROGRAM ELEMENT. PROJECT. TASK Waterborne Comerce Statistics Center AESWRCUI UUR P. 0. Box 61280 *New Orleans, La. 70161 WRSC-CC 11I. CONTROLLING ... controlled cargo end Special Category Items." The 1980 statistics on waterborne exports of domestic and foreign merchandise and non-Department of Defense...Government materials 4119 Empty containers Group 34-fabricated Metal Products, 9999* Department of Defense controlled cargo snd special category Except
A role of high impact weather events in waterborne disease outbreaks in Canada, 1975 - 2001.
Thomas, Kate M; Charron, Dominique F; Waltner-Toews, David; Schuster, Corinne; Maarouf, Abdel R; Holt, John D
2006-06-01
Recent outbreaks of Escherichia coli O157:H7, Campylobacter, and Cryptosporidium have heightened awareness of risks associated with contaminated water supply. The objectives of this research were to describe the incidence and distribution of waterborne disease outbreaks in Canada in relation to preceding weather conditions and to test the association between high impact weather events and waterborne disease outbreaks. We examined extreme rainfall and spring snowmelt in association with 92 Canadian waterborne disease outbreaks between 1975 and 2001, using case-crossover methodology. Explanatory variables including accumulated rainfall, air temperature, and peak stream flow were used to determine the relationship between high impact weather events and the occurrence of waterborne disease outbreaks. Total maximum degree-days above 0 degrees C and accumulated rainfall percentile were associated with outbreak risk. For each degree-day above 0 degrees C the relative odds of an outbreak increased by a factor of 1.007 (95% confidence interval [CI] = 1.002 - 1.012). Accumulated rainfall percentile was dichotomized at the 93rd percentile. For rainfall events greater than the 93rd percentile the relative odds of an outbreak increased by a factor of 2.283 (95% [CI] = 1.216 - 4.285). These results suggest that warmer temperatures and extreme rainfall are contributing factors to waterborne disease outbreaks in Canada. This could have implications for water management and public health initiatives.
Quantifying climate change impacts on runoff of zoonotic pathogens from land
NASA Astrophysics Data System (ADS)
Sterk, Ankie; de Roda Husman, Ana Maria; Stergiadi, Maria; de Nijs, Ton; Schijven, Jack
2013-04-01
Several studies have shown a correlation between rainfall and waterborne disease outbreaks. One of the mechanisms whereby rainfall may cause outbreaks is through an increase in runoff of animal faeces from fields to surface waters. Faeces originating from wildlife, domestic animals or manure-fertilized fields, is considered an important source of zoonotic pathogens to which people may be exposed by water recreation or drinking-water consumption. Climate changes affect runoff because of increasing winter precipitation and more extreme precipitation events, as well as changes in evaporation. Furthermore, drier summers are leading to longer periods of high soil moisture deficits, increasing the hydrophobicity of soil and consequently changing infiltration capacities. A conceptual model is designed to describe the impacts of climate changes on the terrestrial and aquatic ecosystems, which are both directly and indirectly affecting pathogen loads in the environment and subsequent public health risks. One of the major outcomes was the lack of quantitative data and limited qualitative analyses of impacts of climate changes on pathogen runoff. Quantifying the processes by which micro-organisms are transported from fields to waters is important to be able to estimate such impacts to enable targeted implementation of effective intervention measures. A quantitative model using Mathematica software will be developed to estimate concentrations of pathogens originating from overland flow during runoff events. Different input sources will be included by applying different land-use scenarios, including point source faecal pollution from dairy cows and geese and diffuse source pollution by fertilization. Zoonotic pathogens, i.e. Cryptosporidium and Campylobacter, were selected based on transport properties, faecal loads and disease burden. Transport and survival rates of these pathogens are determined including effects of changes in precipitation but also temperature induced changes on die-off. Moreover, besides climate and surface variables, changes in soil or vegetation and adjustments in agricultural policy are considered. Output of this model can be used to assess how expected climate changes could affect pathogen concentrations in surface waters. The long term aim is to include this information in a larger framework, to quantify the impact of climate change on the infection and eventual disease risks due to exposure to water transmitted pathogens.
O'Dwyer, Jean; Morris Downes, Margaret; Adley, Catherine C
2016-02-01
This study analyses the relationship between meteorological phenomena and outbreaks of waterborne-transmitted vero cytotoxin-producing Escherichia coli (VTEC) in the Republic of Ireland over an 8-year period (2005-2012). Data pertaining to the notification of waterborne VTEC outbreaks were extracted from the Computerised Infectious Disease Reporting system, which is administered through the national Health Protection Surveillance Centre as part of the Health Service Executive. Rainfall and temperature data were obtained from the national meteorological office and categorised as cumulative rainfall, heavy rainfall events in the previous 7 days, and mean temperature. Regression analysis was performed using logistic regression (LR) analysis. The LR model was significant (p < 0.001), with all independent variables: cumulative rainfall, heavy rainfall and mean temperature making a statistically significant contribution to the model. The study has found that rainfall, particularly heavy rainfall in the preceding 7 days of an outbreak, is a strong statistical indicator of a waterborne outbreak and that temperature also impacts waterborne VTEC outbreak occurrence.
Waterborne Polyurethane Coatings with Covalently Linked Black Dye Sudan Black B
Sun, Wei; Xu, Haiyan; Xu, Fei
2017-01-01
Colored waterborne polyurethanes have been widely used in paintings, leathers, textiles, and coatings. Here, a series of black waterborne polyurethanes (WPUs) with different ratios of black dye, Sudan Black B (SDB), were prepared by step-growth polymerization. WPU emulsions as obtained exhibit low particle sizes and remarkable storage stability at the same time. At different dye loadings, essential structural, statistical and thermal properties are characterized. FTIR (fourier transform infrared) spectra indicate that SDB is covalently linked into waterborne polyurethane chains. All of the WPUs with covalently linked SDB show better color fastness and resistance of thermal migration than those with SDB mixed physically. Besides, WPUs incorporated SDB covalently with different polymeric diols, polytetramethylene ether glycol (PTMG), polypropylene glycol (PPG), poly-1, 4-butylene adipate glycol (PBA) and polycaprolactone glycol (PCL), were prepared to obtain different properties to cater to a variety of practical demands. By a spraying method, the black WPUs can be directly used as metal coatings without complex dyeing process by simply mixing coating additive and other waterborne resins, which exhibit excellent coating performance. PMID:29143785
The Arsenic crisis in Bangladesh (Invited)
NASA Astrophysics Data System (ADS)
Harvey, C.; Ashfaque, K.; Neumann, R. B.; Badruzzaman, B.; Ali, A.
2010-12-01
The Ganges Delta suffers from water-borne disease. Arsenic in the groundwater pumped from drinking water wells is causing severe and widespread disease, and these wells were installed, in part, to avoid pathogens in the surface water supply. I will discuss the hydrogeologic controls of arsenic concentrations in groundwater, specifically the role of enhanced groundwater circulation driven by irrigation pumping and the effects of the solute loads transported into aquifers with recharge through different surface features, such as rice fields, rivers, and ponds. I will contrast the approaches taken in Southeast Asia for studying groundwater contamination with methods used in the U.S. I will compare findings from several sites in the region and consider how improved models of the coupled hydrologic and biogeochemical system can be used to provide safer water.
Borchardt, Mark A; Stemper, Mary E; Standridge, Jon H
2003-02-01
Gastrointestinal infections of Aeromonas species are generally considered waterborne; for this reason, Aeromonas hydrophila has been placed on the United States Environmental Protection Agency Contaminant Candidate List of emerging pathogens in drinking water. In this study, we compared pulsed-field gel electrophoresis patterns of Aeromonas isolates from stool specimens of patients with diarrhea with Aeromonas isolates from patients' drinking water. Among 2,565 diarrheic stool specimens submitted to a Wisconsin clinical reference laboratory, 17 (0.66%) tested positive for Aeromonas. Groundwater isolates of Aeromonas were obtained from private wells throughout Wisconsin and the drinking water of Aeromonas-positive patients. The analysis showed that the stool and drinking water isolates were genetically unrelated, suggesting that in this population Aeromonas gastrointestinal infections were not linked with groundwater exposures.
Stemper, Mary E.; Standridge, Jon H.
2003-01-01
Gastrointestinal infections of Aeromonas species are generally considered waterborne; for this reason, Aeromonas hydrophila has been placed on the United States Environmental Protection Agency Contaminant Candidate List of emerging pathogens in drinking water. In this study, we compared pulsed-field gel electrophoresis patterns of Aeromonas isolates from stool specimens of patients with diarrhea with Aeromonas isolates from patients’ drinking water. Among 2,565 diarrheic stool specimens submitted to a Wisconsin clinical reference laboratory, 17 (0.66%) tested positive for Aeromonas. Groundwater isolates of Aeromonas were obtained from private wells throughout Wisconsin and the drinking water of Aeromonas-positive patients. The analysis showed that the stool and drinking water isolates were genetically unrelated, suggesting that in this population Aeromonas gastrointestinal infections were not linked with groundwater exposures. PMID:12603994
Hepatitis E Virus: Foodborne, Waterborne and Zoonotic Transmission
Yugo, Danielle M.; Meng, Xiang-Jin
2013-01-01
Hepatitis E virus (HEV) is responsible for epidemics and endemics of acute hepatitis in humans, mainly through waterborne, foodborne, and zoonotic transmission routes. HEV is a single-stranded, positive-sense RNA virus classified in the family Hepeviridae and encompasses four known Genotypes (1–4), at least two new putative genotypes of mammalian HEV, and one floating genus of avian HEV. Genotypes 1 and 2 HEVs only affect humans, while Genotypes 3 and 4 are zoonotic and responsible for sporadic and autochthonous infections in both humans and several other animal species worldwide. HEV has an ever-expanding host range and has been identified in numerous animal species. Swine serve as a reservoir species for HEV transmission to humans; however, it is likely that other animal species may also act as reservoirs. HEV poses an important public health concern with cases of the disease definitively linked to handling of infected pigs, consumption of raw and undercooked animal meats, and animal manure contamination of drinking or irrigation water. Infectious HEV has been identified in numerous sources of concern including animal feces, sewage water, inadequately-treated water, contaminated shellfish and produce, as well as animal meats. Many aspects of HEV pathogenesis, replication, and immunological responses remain unknown, as HEV is an extremely understudied but important human pathogen. This article reviews the current understanding of HEV transmission routes with emphasis on food and environmental sources and the prevalence of HEV in animal species with zoonotic potential in humans. PMID:24071919
[Investigation of a water-borne Salmonella ohio outbreak].
Molinero, M E; Fernández, I; García-Calabuig, M A; Peiró, E
1998-05-01
The genus Salmonella is one of the main causes of foodborne and waterborne illness worldwide. It is a major public health concern almost entirely due to S. enteritidis. However, outbreaks caused by Salmonella ohio are rare. We have not found any reference about salmonellosis by S. ohio whose origin was water of a drinking fountain. An epidemiological survey was carried out to investigate the origin of the outbreak, and information was sought on personal details, symptoms, contact with others who had ill as well as a history of eating. Fecal specimens and water samples were cultured for bacterial pathogens including Salmonella. Salmonella isolates obtained were characterized by stereotyping. A total of 101 persons were exposed. 87 of these were interviewed, but only 59 of these were affected (attack rate: 67.8%), including 56 children and 3 adults. Syndrome was not severe, in general, persisting for a period of 2 days, in average. S. ohio was isolated from the water and from 2 of the 13 stool specimens analysed. The outbreak was caused by consumption of water from a drinking fountain which was contaminated by S. ohio. This fountain had not a chlorination system. An outbreak due to S. ohio whose origin is the consumption of water from a drinking fountain is described for the first time in this paper. It can be concluded the importance of keeping a good epidemiological control system to investigate and prevent outbreaks. The control of drinking fountains is also important, to prevent its contamination.
Health significance and occurrence of injured bacteria in drinking water
NASA Technical Reports Server (NTRS)
McFeters, G. A.; LeChevallier, M. W.; Singh, A.; Kippin, J. S.
1986-01-01
Enteropathogenic and indicator bacteria become injured in drinking water with exposure to sublethal levels of various biological, chemical and physical factors. One manifestation of this injury is the inability to grow and form colonies on selective media containing surfactants. The resulting underestimation of indicator bacteria can lead to a false estimation of water potability. m-T7 medium was developed specifically for the recovery of injured coliforms (both "total" and fecal) in drinking water. The m-T7 method was used to survey operating drinking water treatment and distribution systems for the presence of injured coliforms that were undetected with currently used media. The mean recovery with m-Endo LES medium was less than 1/100 ml while it ranged between 6 and 68/100ml with m-T7 agar. The majority of samples giving positive results with m-T7 medium yielded no detectable coliforms with m-Endo LES agar. Over 95% of the coliform bacteria in these samples were injured. Laboratory experiments were also done to ascribe the virulence of injured waterborne pathogens. Enteropathogens including Salmonella typhimurium, Yersinia enterocolitica and Shigella spp. required up to 20 times the chlorine levels to produce the same injury in enterotoxigenic Escherichia coli (ETEC) and nonpathogenic coliforms. Similar results were seen with Y. enterocolitica exposed to copper. The recovery of ETEC was followed by delayed enterotoxin production, both in vitro and in the gut of experimental animals. This indicates that injured waterborne enteropathogenic bacteria can be virulent.
Hollow silica microspheres for buoyancy-assisted separation of infectious pathogens from stool.
Weigum, Shannon E; Xiang, Lichen; Osta, Erica; Li, Linying; López, Gabriel P
2016-09-30
Separation of cells and microorganisms from complex biological mixtures is a critical first step in many analytical applications ranging from clinical diagnostics to environmental monitoring for food and waterborne contaminants. Yet, existing techniques for cell separation are plagued by high reagent and/or instrumentation costs that limit their use in many remote or resource-poor settings, such as field clinics or developing countries. We developed an innovative approach to isolate infectious pathogens from biological fluids using buoyant hollow silica microspheres that function as "molecular buoys" for affinity-based target capture and separation by floatation. In this process, antibody functionalized glass microspheres are mixed with a complex biological sample, such as stool. When mixing is stopped, the target-bound, low-density microspheres float to the air/liquid surface, which simultaneously isolates and concentrates the target analytes from the sample matrix. The microspheres are highly tunable in terms of size, density, and surface functionality for targeting diverse analytes with separation times of ≤2min in viscous solutions. We have applied the molecular buoy technique for isolation of a protozoan parasite that causes diarrheal illness, Cryptosporidium, directly from stool with separation efficiencies over 90% and low non-specific binding. This low-cost method for phenotypic cell/pathogen separation from complex mixtures is expected to have widespread use in clinical diagnostics as well as basic research. Copyright © 2016 Elsevier B.V. All rights reserved.
Protozoal agents: what are the dangers for the public water supply?
Steiner, T S; Thielman, N M; Guerrant, R L
1997-01-01
Safe and efficient treatment of drinking water has been one of the major public health advances of the twentieth century. People in developed countries generally take for granted that their water is safe to drink, a luxury the majority of the world's population does not have. The leading cause of infant mortality in the developing world is infectious diarrhea, and the prevalence of diarrheal pathogens is largely influenced by the quality and quantity of clean water available for drinking and washing. Until recently, modern water treatment had all but eliminated these concerns in developed nations. Over the past two decades, however, the safety of our water supply has been threatened by the emergence of Cryptosporidium parvum, a protozoal pathogen. The hearty oocysts of this organism survive chlorination and filtration to cause a diarrheal illness that, while unpleasant enough in healthy people, is devastating in immunocompromised individuals. The 1993 Milwaukee outbreak, in which 403,000 people developed diarrhea from drinking water that met all the updated federal safety standards, demonstrated the tremendous public health importance of this organism. While earlier attention had focused on Giardia and amebic infections, the other "emerging" protozoan besides Cryptosporidium is Cyclospora. This review discusses the protozoal pathogens, including Cryptosporidium parvum, Giardia lamblia, Entamoeba histolytica, and Cyclospora cayetanensis, that cause waterborne diarrheal outbreaks and the threats they pose to the public.
Donaldson, K.A.; Griffin, Dale W.; Paul, J.H.
2002-01-01
A method was developed for the quantitative detection of pathogenic human enteroviruses from surface waters in the Florida Keys using Taqman (R) one-step Reverse transcription (RT)-PCR with the Model 7700 ABI Prism (R) Sequence Detection System. Viruses were directly extracted from unconcentrated grab samples of seawater, from seawater concentrated by vortex flow filtration using a 100kD filter and from sponge tissue. Total RNA was extracted from the samples, purified and concentrated using spin-column chromatography. A 192-196 base pair portion of the 5??? untranscribed region was amplified from these extracts. Enterovirus concentrations were estimated using real-time RT-PCR technology. Nine of 15 sample sites or 60% were positive for the presence of pathogenic human enteroviruses. Considering only near-shore sites, 69% were positive with viral concentrations ranging from 9.3viruses/ml to 83viruses/g of sponge tissue (uncorrected for extraction efficiency). Certain amplicons were selected for cloning and sequencing for identification. Three strains of waterborne enteroviruses were identified as Coxsackievirus A9, Coxsackievirus A16, and Poliovirus Sabin type 1. Time and cost efficiency of this one-step real-time RT-PCR methodology makes this an ideal technique to detect, quantitate and identify pathogenic enteroviruses in recreational waters. Copyright ?? 2002 Elsevier Science Ltd.
Huang, Chengchen; Hu, Yue; Wang, Lin; Wang, Yuanfei; Li, Na; Guo, Yaqiong; Xiao, Lihua
2017-01-01
ABSTRACT The environmental transport of Cryptosporidium spp. through combined sewer overflow (CSO) and the occurrence of several emerging human-pathogenic Cryptosporidium species in developing countries remain unclear. In this study, we collected 40 CSO samples and 40 raw wastewater samples from Shanghai, China, and examined them by PCR and DNA sequencing for Cryptosporidium species (targeting the small subunit rRNA gene) and Giardia duodenalis (targeting the triosephosphate isomerase, β-giardin, and glutamate dehydrogenase genes) and Enterocytozoon bieneusi (targeting the ribosomal internal transcribed spacer) genotypes. Human-pathogenic Cryptosporidium species were further subtyped by sequence analysis of the 60-kDa glycoprotein gene, with additional multilocus sequence typing on the emerging zoonotic pathogen Cryptosporidium ubiquitum. Cryptosporidium spp., G. duodenalis, and E. bieneusi were detected in 12 and 15, 33 and 32, and 37 and 40 CSO and wastewater samples, respectively, including 10 Cryptosporidium species, 3 G. duodenalis assemblages, and 8 E. bieneusi genotypes. In addition to Cryptosporidium hominis and Cryptosporidium parvum, two new pathogens identified in industrialized nations, C. ubiquitum and Cryptosporidium viatorum, were frequently detected. The two novel C. ubiquitum subtype families identified appeared to be genetic recombinants of known subtype families. Similarly, the dominant group 1 E. bieneusi genotypes and G. duodenalis subassemblage AII are known human pathogens. The similar distribution of human-pathogenic Cryptosporidium species and E. bieneusi and G. duodenalis genotypes between wastewater and CSO samples reaffirms that storm overflow is potentially a significant contamination source of pathogens in surface water. The frequent identification of C. ubiquitum and C. viatorum in urban wastewater suggests that these newly identified human pathogens may be endemic in China. IMPORTANCE Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are major waterborne pathogens. Their transport into surface water through combined sewer overflow, which remains largely untreated in developing countries, has not been examined. In addition, the identification of these pathogens to genotypes and subtypes in urban storm overflow and wastewater is necessary for rapid and accurate assessment of pathogen transmission in humans and transport in the environment. Data from this study suggest that, like untreated urban wastewater, combined sewer overflow is commonly contaminated with human-pathogenic Cryptosporidium, G. duodenalis, and E. bieneusi genotypes and subtypes, and urban storm overflow potentially plays a significant role in the contamination of drinking source water and recreational water with human pathogens. They also indicate that Cryptosporidium ubiquitum and Cryptosporidium viatorum, two newly identified human pathogens, may be common in China, and genetic recombination can lead to the emergence of novel C. ubiquitum subtype families. PMID:28600310
Curtis, Dennis; Hill, Arthur; Wilcock, Anne; Charlebois, Sylvain
2014-10-01
The World Ranking Food Safety Performance reports by Charlebois in 2008 and 2010 importantly stimulated international discussion and encouraged efforts to establish realistic international benchmarks for food safety performance among Organisation for Economic Cooperation and Development (OECD) countries. This paper presents the international incidence of 5 common foodborne pathogens and describes the challenges of comparing international data. Data were compiled from surveillance authorities in the countries, such as the Natl. Notifiable Diseases Surveillance System of Australia; the Canadian Notifiable Diseases Surveillance System; the European Food Safety Authority, EFSA; the Ministry of Health, Labour and Welfare of Japan; New Zealand Food Safety Authority; and the U.S. Center for Disease Control and Prevention. The highest average rates in cases per 100000 people over the 12-y period from 2000 to 2011 for Campylobacter spp. (237.47), Salmonella spp. (67.08), Yersinia spp. (12.09), Verotoxigenic/Shiga toxin producing Escherichia coli (3.38), and Listeria monocytogenes (1.06) corresponded, in order, to New Zealand, Belgium, Finland, Canada, and Denmark. Comparatively, annual average rates for these 5 pathogens showed an increase over the 12-y period in 28%, 17%, 14%, 50%, and 6% of the countries for which data were available. Salmonella spp. showed a decrease in 56% of the countries, while incidence of L. monocytogenes was constant in most countries (94%). Variable protocols for monitoring incidence of pathogens among OECD countries remain. Nevertheless, there is evidence of sufficient standardization of monitoring protocols such as the European Surveillance System, which has contributed to reduce this gap. © 2014 Institute of Food Technologists®
75 FR 26256 - Agency Forms Undergoing Paperwork Reduction Act Review
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-11
... and Enterovirus surveillance, rabies, waterborne diseases, cholera and other vibrio illnesses... System 90 52 10/60 (NREVSS) Rabies (electronic) 50 12 8/60 Rabies (paper) 3 12 15/60 Waterborne Diseases...
DeForest, David K; Brix, Kevin V; Elphick, James R; Rickwood, Carrie J; deBruyn, Adrian M H; Tear, Lucinda M; Gilron, Guy; Hughes, Sarah A; Adams, William J
2017-09-01
There is consensus that fish are the most sensitive aquatic organisms to selenium (Se) and that Se concentrations in fish tissue are the most reliable indicators of potential toxicity. Differences in Se speciation, biological productivity, Se concentration, and parameters that affect Se bioavailability (e.g., sulfate) may influence the relationship between Se concentrations in water and fish tissue. It is desirable to identify environmentally protective waterborne Se guidelines that, if not exceeded, reduce the need to directly measure Se concentrations in fish tissue. Three factors that should currently be considered in developing waterborne Se screening guidelines are 1) differences between lotic and lentic sites, 2) the influence of exposure concentration on Se partitioning among compartments, and 3) the influence of sulfate on selenate bioavailability. Colocated data sets of Se concentrations in 1) water and particulates, 2) particulates and invertebrates, and 3) invertebrates and fish tissue were compiled; and a quantile regression approach was used to derive waterborne Se screening guidelines. Use of a regression-based approach for describing relationships in Se concentrations between compartments reduces uncertainty associated with selection of partitioning factors that are generally not constant over ranges of exposure concentrations. Waterborne Se screening guidelines of 6.5 and 3.0 μg/L for lotic and lentic water bodies were derived, and a sulfate-based waterborne Se guideline equation for selenate-dominated lotic waters was also developed. Environ Toxicol Chem 2017;36:2503-2513. © 2017 SETAC. © 2017 SETAC.
The hospital water supply as a source of nosocomial infections: a plea for action.
Anaissie, Elias J; Penzak, Scott R; Dignani, M Cecilia
2002-07-08
Microbiologically contaminated drinking water is a cause of community-acquired infection, and guidelines for prevention of such infections have been established. Microbes in hospital water can also cause nosocomial infection, yet guidelines for preventing such infections do not exist. The purpose of this review is to assess the magnitude of the problem caused by waterborne nosocomial infections and to plea for immediate action for their prevention. We conducted a MEDLINE search of the literature published between January 1, 1966, and December 31, 2001. Investigations in which microorganisms (other than Legionella species) caused waterborne nosocomial infections and public health agency recommendations for drinking water. Forty-three outbreaks of waterborne nosocomial infections have been reported, and an estimated 1400 deaths occur each year in the United States as a result of waterborne nosocomial pneumonias caused by Pseudomonas aeruginosa alone. Despite the availability of effective control measures, no clear guidelines exist for the prevention of these infections. By contrast, guidelines for the prevention of community-acquired waterborne infections are now routinely used. Hospitals caring for patients at high risk for infection do not enforce the standards of water quality recommended by US and United Kingdom public health agencies for the patients' community counterparts. Because of the seriousness of these nosocomial waterborne infections and the availability, low cost, and proven effectiveness of sterile water, we recommend that hospitalized patients at high risk for infection avoid exposure to hospital water and use sterile water instead.
Cleveland, Laverne; Little, Edward E.; Buckler, Denny R.; Wiedmeyer, Raymond H.
1993-01-01
Juvenile bluegill (Lepomis macrochirus) were exposed to waterborne selenium as a 6:1 mixture of selenate to selenite (as Se) for 60 d and to dietary seleno-l-methionine for 90 d. Measured concentrations of total selenium in the waterborne exposure ranged from 0.16 to 2.8 mg/l, and concentrations of seleno-l-methionine in the test diet ranged from 2.3 to 25.0 mg/kg wet weight. Mortality, body weight, condition factor, swimming and feeding behavior, aggression, and selenium tissue residues were monitored during the tests. Increased mortality at measured concentrations of 0.64 mg Se/l and greater was the primary adverse effect of waterborne selenium on the juvenile bluegill. Bluegill exposed to 2.8 mg/l of waterborne Se for 30 d exhibited a significant reduction in condition factor (K), whereas dietary exposure of bluegill to 25 mg Se/kg for 30 d and 13 mg Se/kg or greater for 90 d elicited significant reductions in K. Mortality and swimming activity of bluegill were not affected in the dietary exposure. Net accumulation of Se from both water and diet was directly related to exposure concentration. Bioconcentration factors ranged from 5 to 7 for bluegill exposed to waterborne Se and from 0.5 to 1.0 for fish exposed to dietary Se. Results of these laboratory tests indicate that survival of bluegill may be impaired in natural waters with elevated Se concentrations.
Food- and waterborne disease outbreaks in Australian long-term care facilities, 2001-2008.
Kirk, Martyn D; Lalor, Karin; Raupach, Jane; Combs, Barry; Stafford, Russell; Hall, Gillian V; Becker, Niels
2011-01-01
Abstract Food- or waterborne diseases in long-term care facilities (LTCF) can result in serious outcomes, including deaths, and they are potentially preventable. We analyzed data collected by OzFoodNet on food- and waterborne disease outbreaks occurring in LTCF in Australia from 2001 to 2008. We compared outbreaks by the number of persons affected, etiology, and implicated vehicle. During 8 years of surveillance, 5.9% (55/936) of all food- and waterborne outbreaks in Australia occurred in LTCF. These LTCF outbreaks affected a total of 909 people, with 66 hospitalized and 23 deaths. The annual incidence of food- or waterborne outbreaks was 1.9 (95% confidence intervals 1.0-3.7) per 1000 facilities. Salmonella caused 17 outbreaks, Clostridium perfringens 14 outbreaks, Campylobacter 8 outbreaks, and norovirus 1 outbreak. Residents were at higher risk of death during outbreaks of salmonellosis than for all other outbreaks combined (relative risk 7.8, 95% confidence intervals 1.8-33.8). Of 15 outbreaks of unknown etiology, 11 were suspected to be due to C. perfringens intoxication. Food vehicles were only identified in 27% (14/52) of outbreaks, with six outbreak investigations implicating pureed foods. Dishes containing raw eggs were implicated as the cause of four outbreaks. Three outbreaks of suspected waterborne disease were attributed to rainwater collected from facility roofs. To prevent disease outbreaks, facilities need to improve handling of pureed foods, avoid feeding residents raw or undercooked eggs, and ensure that rainwater tanks have a scheduled maintenance and disinfection program.
Heavy rainfall and waterborne disease outbreaks: the Walkerton example.
Auld, Heather; MacIver, D; Klaassen, J
Recent research indicates that excessive rainfall has been a significant contributor to historical waterborne disease outbreaks. The Meteorological Service of Canada, Environment Canada, provided an analysis and testimony to the Walkerton Inquiry on the excessive rainfall events, including an assessment of the historical significance and expected return periods of the rainfall amounts. While the onset of the majority of the Walkerton, Ontario, Escherichia coli O157:H7 and Campylobacter outbreak occurred several days after a heavy rainfall on May 12, the accumulated 5-d rainfall amounts from 8-12 May were particularly significant. These 5-d accumulations could, on average, only be expected once every 60 yr or more in Walkerton and once every 100 yr or so in the heaviest rainfall area to the south of Walkerton. The significant link between excess rainfall and waterborne disease outbreaks, in conjunction with other multiple risk factors, indicates that meteorological and climatological conditions need to be considered by water managers, public health officials, and private citizens as a significant risk factor for water contamination. A system to identify and project the impacts of such challenging or extreme weather conditions on water supply systems could be developed using a combination of weather/climate monitoring information and weather prediction or quantitative precipitation forecast information. The use of weather monitoring and forecast information or a "wellhead alert system" could alert water system and water supply managers on the potential response of their systems to challenging weather conditions and additional requirements to protect health. Similar approaches have recently been used by beach managers in parts of the United States to predict day-to-day water quality for beach advisories.
[Waterborne diseases outbreaks in the Czech Republic, 1995-2005].
Kozísek, F; Jeligová, H; Dvoráková, A
2009-08-01
Despite considerable advances in drinking water safety assurance and adherence to the public health standards, waterborne diaseases outbreaks have still been observed even in industrialized countries. The study objective was to map such outbreaks in the Czech Republic in 1995-2005. In this study, an outbreak is the occurrence of more cases of disease than normally expected within a specific place over a given period of time and a waterborne disease is a disease where water is the vehicle or source of infection. The data on waterborne outbreaks was obtained from the EPIDAT database (national infectious diseases reporting system) information provided by epidemiologists of all regional public health authorities and the National Reference Laboratory for Legionella. In 1995 - 2005, 33 outbreaks with water indicated as the route of transmission were recorded in the Czech Republic. The leading cause was unsafe drinking water (27 outbreaks), mainly from wells (19 outbreaks); nevertheless, the most serious consequences were observed in two outbreaks caused by microbiologically contaminated hot water. Other sources of waterborne infection were mineral water springs, a swimming pool and a brook. The total of reported cases of waterborne diseases was 1655, 356 hospitalisations and ten deaths due to legionellosis were recorded. The highest number of outbreaks (7) as well as the highest number of cases (841) were reported in 1997. Comparison of two five-year periods, i.e. 1996-2000 and 2001-2005, showed a nearly one third decrease in the total of outbreaks and a half reduction in the total of cases in the latter. In view of the limited length of monitoring, it is not possible to say with certainty whether it is a random distribution or an actual trend. Almost two thirds of cases were diagnosed as acute gastroenteritis of probable infectious origin and other frequent waterborne diseases were viral hepatitis A and bacillary dysentery. When analyzing the described outbreaks, it should be taken into account that only the diagnosed and reported outbreak cases are covered, while the actual number of cases is likely to be underreported. Although no evidence is available that any vast and serious waterborne diseases outbreaks escaped reporting, some small and less serious outbreaks may have occurred unnoticed. In the future, the diagnosis, investigation and evaluation of waterborne diseases outbreaks should be improved, among others by implementing an evidence-based classification system and issuing regular surveys of outbreaks and their causes which would be helpful in preventing failures in other similar water sources.
Long term striping alternatives for bridge decks : final report, January 2009.
DOT National Transportation Integrated Search
2009-01-01
This study evaluated the performance of the following pavement marking materials on Portland cement concrete bridge decks: Waterborne traffic paint: Ennis fast dry waterborne traffic paint; Thermoplastic: Swarcotherm alkyd; Preformed thermoplastic: P...
DEVELOPMENT OF APTAMERS TO WATERBORNE PARASITES
The Safe Drinking Water Act Amendment of 1996 mandates that the U. S. Environmental Protection Agency (EPA) evaluate public health risks associated with drinking water contaminants to include waterborne parasites, such as Cryptosporidium and Giardia. Additionally, the Agency est...
IMPROVING WATERBORNE DISEASE OUTBREAK INVESTIGATIONS
This article summarizes the discussions and conclusions of a workshop held December 7-8, 1998, to consider the inherent limitations and weaknesses of waterborne outbreak investigations and make recommendations for their improvement. In recent years, an increased number of suspec...
ASSESSING WATERBORNE RISKS: AN INTRODUCTION
Information in this article can help readers evaluate the results of epidemiologic studies of
waterborne disease risks. It is important that readers understand the various epidemiologic study
designs, their strengths and limitations, and potential biases. Terminolog...
The primary object of the microbiology of drinking water is to prevent waterborne disease. A drinking-water system can minimize waterborne disease by employing proper treatment and cntrol practices, and by monitoring the effectiveness of these practices. Here, these issues are ad...
IMPROVING WATERBORNE DISEASE SURVEILLANCE
Public health surveillance has played a key role in controlling the spread of communicable disease and identifying the need for specific publich health practices, such as the filteration and chlorination of drinking water supplies. However, the characteristics of waterborne ou...
Waterborne Disease Outbreaks— United States, 2009–2014
Background: The Centers for Disease Control and Prevention (CDC) has conducted national surveillance for waterborne disease outbreaks since 1971 in partnership with the Council of State and Territorial Epidemiologists and the United States Environmental Protection Agency (USEPA)....
[Waterborne diseases and basic sanitation in Colombia].
Rodríguez Miranda, Juan P; García-Ubaque, César A; García-Ubaque, Juan C
2016-01-01
To analyze the relationship of sewerage coverage and wastewater treatment with waterborne disease behaviour. A descriptive retrospective study was conducted using secondary sources (document review and information available in databases) about basic sanitation coverage, treatment of domestic sewage in the country and the prevalence of waterborne diseases during the period 2008-2014. The country invested USD 1,100 million in the implementation of wastewater treatment systems from 2011 until the first half of 2013. However, the incidence of waterborne diseases, such as acute diarrheal disease, foodborne diseases and typhoid and paratyphoid fever did not decrease during the period 2008-2014; only hepatitis A registered a decrease. Investment in water supply and sewerage systems is relevant to improve health conditions of the population and to reduce the incidence and prevalence of various health conditions; however, it is necessary to address other aspects such as health education and social empowerment to address this problem more efficiently.
Hoxie, N J; Davis, J P; Vergeront, J M; Nashold, R D; Blair, K A
1997-12-01
This study estimated the magnitude of cryptosporidiosis-associated mortality in the Milwaukee vicinity for 2 years following a massive waterborne outbreak. Death certificates were reviewed. During approximately 2 years before the outbreak, cryptosporidiosis was listed as an underlying or contributing cause of death on the death certificates of four Milwaukee-vicinity residents. In the approximately 2 years after the outbreak, this number was 54, of whom 85% had acquired immunodeficiency syndrome (AIDS) listed as the underlying cause of death. In the first 6 months after the outbreak, the number of death certificates indicating AIDS, but not cryptosporidiosis, as a cause of death was 19 (95% confidence interval = 12.26) higher than preoutbreak trends would have predicted. Waterborne outbreaks of cryptosporidium infection can result in significant mortality, particularly among immunocompromised populations. Any discussion of policies to ensure safe drinking water must consider the potential fatal consequences of waterborne cryptosporidiosis among immunocompromised populations.
Literature Review of Associations among Attributes of Reported Drinking Water Disease Outbreaks
Ligon, Grant; Bartram, Jamie
2016-01-01
Waterborne disease outbreaks attributed to various pathogens and drinking water system characteristics have adversely affected public health worldwide throughout recorded history. Data from drinking water disease outbreak (DWDO) reports of widely varying breadth and depth were synthesized to investigate associations between outbreak attributes and human health impacts. Among 1519 outbreaks described in 475 sources identified during review of the primarily peer-reviewed, English language literature, most occurred in the U.S., the U.K. and Canada (in descending order). The outbreaks are most frequently associated with pathogens of unknown etiology, groundwater and untreated systems, and catchment realm-associated deficiencies (i.e., contamination events). Relative frequencies of outbreaks by various attributes are comparable with those within other DWDO reviews, with water system size and treatment type likely driving most of the (often statistically-significant at p < 0.05) differences in outbreak frequency, case count and attack rate. Temporal analysis suggests that while implementation of surface (drinking) water management policies is associated with decreased disease burden, further strengthening of related policies is needed to address the remaining burden attributed to catchment and distribution realm-associated deficiencies and to groundwater viral and disinfection-only system outbreaks. PMID:27240387
Hunter, Paul R; Zmirou-Navier, Denis; Hartemann, Philippe
2009-04-01
Recent evidence suggests that many improved drinking water supplies suffer from poor reliability. This study investigates what impact poor reliability may have on achieving health improvement targets. A Quantitative Microbiological Risk Assessment was conducted of the impact of interruptions in water supplies that forced people to revert to drinking raw water. Data from the literature were used to construct models on three waterborne pathogens common in Africa: Rotavirus, Cryptosporidium and Enterotoxigenic E. coli. Risk of infection by the target pathogens is substantially greater on days that people revert to raw water consumption. Over the course of a few days raw water consumption, the annual health benefits attributed to consumption of water from an improved supply will be almost all lost. Furthermore, risk of illness on days drinking raw water will fall substantially on very young children who have the highest risk of death following infection. Agencies responsible for implementing improved drinking water provision will not make meaningful contributions to public health targets if those systems are subject to poor reliability. Funders of water quality interventions in developing countries should put more effort into auditing whether interventions are sustainable and whether the health benefits are being achieved.
Literature Review of Associations among Attributes of Reported Drinking Water Disease Outbreaks.
Ligon, Grant; Bartram, Jamie
2016-05-27
Waterborne disease outbreaks attributed to various pathogens and drinking water system characteristics have adversely affected public health worldwide throughout recorded history. Data from drinking water disease outbreak (DWDO) reports of widely varying breadth and depth were synthesized to investigate associations between outbreak attributes and human health impacts. Among 1519 outbreaks described in 475 sources identified during review of the primarily peer-reviewed, English language literature, most occurred in the U.S., the U.K. and Canada (in descending order). The outbreaks are most frequently associated with pathogens of unknown etiology, groundwater and untreated systems, and catchment realm-associated deficiencies (i.e., contamination events). Relative frequencies of outbreaks by various attributes are comparable with those within other DWDO reviews, with water system size and treatment type likely driving most of the (often statistically-significant at p < 0.05) differences in outbreak frequency, case count and attack rate. Temporal analysis suggests that while implementation of surface (drinking) water management policies is associated with decreased disease burden, further strengthening of related policies is needed to address the remaining burden attributed to catchment and distribution realm-associated deficiencies and to groundwater viral and disinfection-only system outbreaks.
Biocolloid transport in water saturated columns packed with sand
NASA Astrophysics Data System (ADS)
Syngouna, V. I.; Chrysikopoulos, C.
2010-12-01
Protection of groundwater supplies from microbial contamination necessitates a solid understanding of the factors controlling the migration and retention of pathogenic organisms (biocolloids) in the subsurface. The transport behavior of three waterborne pathogens (Escherichia coli, MS2, and ΦΧ174) was investigated using laboratory-scale columns packed with clean quartz sand. Various grain sizes and pore water velocities were examined. Though coliform bacteria and coliphages are used worldwide to indicate fecal pollution of groundwater, the various parameters controlling the transport of Escherichia coli MS2 and ΦΧ174 in the subsurface are not fully understood. In this study, the attachment behavior of Escherichia coli, MS2, and ΦΧ174 onto ultra-pure quartz sand were evaluated. The mass recoveries of the three biocolloids examined were found to be proportional to the sand size. The observed mass recoveries were in the order: Escherichia coli > ΦΧ174 > MS2. To assess the importance of biocolloid attachment, the single collector removal efficiency, and the collision efficiency were quantified using the classical colloid filtration theory. Our results indicate that the secondary energy minimum plays an important role in biocolloid deposition even for smaller biocolloid particles (e.g. viruses).
Prevalence and genotypes of Enterocytozoon bieneusi in China.
Wang, Sha-Sha; Wang, Rong-Jun; Fan, Xian-Cheng; Liu, Ting-Li; Zhang, Long-Xian; Zhao, Guang-Hui
2018-07-01
Enterocytozoon bieneusi has been considered as the most frequently diagnosed microsporidian species in humans and various animal species, accounting for more than 90% of the cases of human microsporidiosis. Spores of this pathogen excreted from both symptomatic and asymptomatic hosts into environment also would be an important source of waterborne outbreak of microsporidiosis. Due to limited effective drugs available but with too much side effects to mammals (eg. toxic), accurate characterization of E. bieneusi in both humans and animals is essential to implement effective control strategies to this pathogen. In China, E. bieneusi infection was presented in humans and some animals with high prevalence. Analysis of genetic variations of the internal transcribed spacer (ITS) sequences found 361 genotypes in China, and some novel genotypes were identified in some specific hosts. Additionally, associations between infections and some risk factors were also observed. In the present article, we reviewed the current status of prevalence, genotypes, multilocus genotypes (MLGs) in humans, various animals and waters in China. These findings will provide basic information for developing effective control strategies against E. bieneusi infection in China as well as other countries. Copyright © 2018 Elsevier B.V. All rights reserved.
SURVEILLANCE FOR WATERBORNE-DISEASE OUTBREAKS-UNITED STATES, 1997-1998
PROBLEM/CONDITION: Since 1971, CDC and the U.S. Environmental Protection Agency (EPA) have maintained a collaborative surveillance system for collecting and periodically reporting data relating to occurrences and causes of waterborne-disease outbreaks (WBDOs). REPORTING PERIOD CO...
Evaluation and specification of high build and special use waterborne pavement markings.
DOT National Transportation Integrated Search
2014-01-01
High build waterborne traffic paints and highly retro-reflective elements were applied at various locations to evaluate their : practicality for use by NYSDOT Maintenance forces. In addition, highly reflective elements were applied within grooved in ...
Water Under Fire: A Seven Part Video Series on Canada's Water
NASA Astrophysics Data System (ADS)
Mrazek, R.; Byrne, J.; Rabe, N.; Gallant, G.
2003-12-01
Canada's water is under escalating pressure from a host of threats. Increasingly, our water is being tainted, misused and over allocated. Experts have identified a multitude of threats to water quantity and quality. Among them, climate change impacts on water supply, and the effects of pesticides, pathogens, industrial waste, urban runoff, and rising demands. These and other threats are the roots to a serious shortage of high quality, safe water sources. In the 1990s, waterborne diseases have re-emerged as one of the primary health issues on a national and global scale. This seven-part video series brings science voices together and provides a nationwide context. The first six programs in the series explore regional concerns: Rocky Mountains, Prairie Waters, Northern Waters, Great Lakes Basin, St. Lawrence and Atlantic Canada. The final program covers the national and international perspectives.
U.S. drinking water challenges in the twenty-first century.
Levin, Ronnie B; Epstein, Paul R; Ford, Tim E; Harrington, Winston; Olson, Erik; Reichard, Eric G
2002-02-01
The access of almost all 270 million U.S. residents to reliable, safe drinking water distinguishes the United States in the twentieth century from that of the nineteenth century. The United States is a relatively water-abundant country with moderate population growth; nonetheless, current trends are sufficient to strain water resources over time, especially on a regional basis. We have examined the areas of public water infrastructure, global climate effects, waterborne disease (including emerging and resurging pathogens), land use, groundwater, surface water, and the U.S. regulatory history and its horizon. These issues are integrally interrelated and cross all levels of public and private jurisdictions. We conclude that U.S. public drinking water supplies will face challenges in these areas in the next century and that solutions to at least some of them will require institutional changes.
Role and functions of beneficial microorganisms in sustainable aquaculture.
Zhou, Qunlan; Li, Kangmin; Jun, Xie; Bo, Liu
2009-08-01
This paper aims to review the development of scientific concepts of microecology and ecology of microbes and the role and functions of beneficial microorganisms in aquaculture and mariculture. Beneficial microorganisms play a great role in natural and man-made aquatic ecosystems based on the co-evolution theory in living biosphere on earth. Their functions are to adjust algal population in water bodies so as to avoid unwanted algal bloom; to speed up decomposition of organic matter and to reduce CODmn, NH3-N and NO2-N in water and sediments so as to improve water quality; to suppress fish/shrimp diseases and water-borne pathogens; to enhance immune system of cultured aquatic animals and to produce bioactive compounds such as vitamins, hormones and enzymes that stimulate growth, thus to decrease the FCR of feed.
[Intestinal parasitic diseases as a global health problem].
Chacín-Bonilla, Leonor
2013-03-01
In today's world, parasitic disease agents are not restricted by geography or economy, and have become a significant global threat. The increasing globalization of the fresh produce market and greater international trade and travels, have contributed to the spread of these organisms in the industrialized world. Parasitic protozoa cause waterborne and foodborne outbreaks of diarrhea. The unprecedented flow of people introduces cultural and behavior patterns around the world; the increasing tendency to eat raw or undercooked meat and seafood, favors the dissemination of several parasitic pathogens. Climate changes are predicted to cause a global increase in soil-transmitted helminthiases. The multidisciplinary study of these agents, and the interaction among scientists, global health organizations and governments are imperative to reduce the burden of these diseases and improve the life of a large segment of the world population.
U.S. drinking water challenges in the twenty-first century.
Levin, Ronnie B; Epstein, Paul R; Ford, Tim E; Harrington, Winston; Olson, Erik; Reichard, Eric G
2002-01-01
The access of almost all 270 million U.S. residents to reliable, safe drinking water distinguishes the United States in the twentieth century from that of the nineteenth century. The United States is a relatively water-abundant country with moderate population growth; nonetheless, current trends are sufficient to strain water resources over time, especially on a regional basis. We have examined the areas of public water infrastructure, global climate effects, waterborne disease (including emerging and resurging pathogens), land use, groundwater, surface water, and the U.S. regulatory history and its horizon. These issues are integrally interrelated and cross all levels of public and private jurisdictions. We conclude that U.S. public drinking water supplies will face challenges in these areas in the next century and that solutions to at least some of them will require institutional changes. PMID:11834462
SURVEILLANCE FOR WATERBORNE-DISEASE OUTBREAKS - UNITED STATES, 1999-2000
PROBLEM/CONDITION: Since 1971, CDC, the U.S. Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists (CSTE) have maintained a collaborative surveillance system for the occurrences and causes of waterborne-disease outbreaks (WBDOs).This surv...
40 CFR 60.432 - Standard for volatile organic compounds.
Code of Federal Regulations, 2011 CFR
2011-07-01
.... 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... period. The water used includes only that water contained in the waterborne raw inks and related coatings and the water added for dilution with waterborne ink systems. ...
40 CFR 60.432 - Standard for volatile organic compounds.
Code of Federal Regulations, 2010 CFR
2010-07-01
.... 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... period. The water used includes only that water contained in the waterborne raw inks and related coatings and the water added for dilution with waterborne ink systems. ...
DOT National Transportation Integrated Search
2005-12-15
The annual revision of the Waterborne : Transportation Lines of the United States : (WTLUS) contains summary information of : the vessel companies and their American : flag vessels operating or available for : operation on 31 December 2004 including ...
National parks of New York harbor waterborne transportation plan
DOT National Transportation Integrated Search
2001-04-01
This Waterborne Transportation Study assesses the viability of water transportation as an access mode serving Gateway and other assets of the National Parks of New York Harbor, and develops a preliminary ferry service concept plan to serve the needs ...
Swimming Associated Disease Outbreaks.
ERIC Educational Resources Information Center
Cabelli, V. J.
1978-01-01
Presents a literature review of recreational waterborne outbreaks and cases of disease, covering publications of 1976-77. This review includes: (1) retrospective and prospective epidemiological studies; (2) predictive models of the risk of recreational waterborn disease. A list of 35 references is also presented. (HM)
Cadmium affects the social behaviour of rainbow trout, Oncorhynchus mykiss.
Sloman, Katherine A; Scott, Graham R; Diao, Zhongyu; Rouleau, Claude; Wood, Chris M; McDonald, D Gord
2003-10-29
The present study investigated both the effects of cadmium on the social interactions of rainbow trout and the differential accumulation of waterborne cadmium among social ranks of fish. Fish exposed to waterborne cadmium concentrations of 2 microg l(-1) for 24 h, followed by a 1, 2 or 3 day depuration period in clean water, had a decreased ability to compete with non-exposed fish. However, the competitive ability of exposed fish given a 5 day depuration period was not significantly impaired. Cadmium accumulated in the olfactory apparatus of fish exposed to waterborne cadmium for 24 h and decreased significantly only after 5 days depuration in clean water. Among groups of ten fish held in stream tanks, where all fish were exposed to cadmium, there were significant effects on social behaviour and growth rate. Dominance hierarchies formed faster among fish exposed to cadmium than among control fish, and overall growth rates were higher in the cadmium treatment. In groups of ten fish, social status also affected tissue accumulation of cadmium during waterborne exposure, with dominant fish accumulating more cadmium at the gill. In conclusion, exposure to low levels of cadmium, affects the social behaviour of fish, in part due to accumulation in the olfactory apparatus, and dominant fish accumulate more gill cadmium than subordinates during chronic waterborne exposure.
NASA Astrophysics Data System (ADS)
Wu, Zhihao; You, Feng; Liu, Hongjun; Liu, Mengxia; Li, Jun; Zhang, Peijun
2012-03-01
The concentration of Fe(II) is high in some groundwater supplies used in turbot culture, and the toxicity of waterborne Fe(II) is unknown. We investigated the stress responses of juvenile turbot, Scophthalmus maximus, exposed to Fe(II) of different concentrations (0.01, 0.05, 0.1, 0.5, 1, and 2 mg/L) for 1, 7, 14, and 28 d, under the same ambient conditions of other parameters. Changes in respiratory rate, hematological parameters, and gill structure were determined. The results show that waterborne Fe(II) did not cause severe hematological perturbation to turbot. A low-medium Fe(II) concentration (lower than 0.1 mg/L) could boost the respiratory rate, and caused no or very limited damage to fish. A high Fe(II) concentration (0.1 mg/L or higher), however, caused gill damage, such as vacuoles in branchial lamellae, epithelial necrosis, and hypertrophy of epithelial cells, and even death after extended exposure time. Therefore, excess waterborne Fe(II) and long-term exposure to Fe(II) could be responsible for poor growth and high mortality of turbot in culture. The concentration of waterborne Fe(II) in turbot culture should be kept below 0.1 mg/L.
NASA Astrophysics Data System (ADS)
Wang, Haihua; Wen, Huan; Hu, Bin; Fei, Guiqiang; Shen, Yiding; Sun, Liyu; Yang, Dong
2017-03-01
Waterborne polyaniline (PANI) dispersion has got extensive attention due to its environmental friendliness and good processability, whereas the storage stability and mechanical property have been the challenge for the waterborne PANI composites. Here we prepare for waterborne PANI dispersion through the chemical graft polymerisation of PANI into epichlorohydrin modified poly (vinyl alcohol) (EPVA). In comparison with waterborne PANI dispersion prepared through physical blend and in situ polymerisation, the storage stability of PANI-g-EPVA dispersion is greatly improved and the dispersion keeps stable for one year. In addition, the as-prepared PANI-g-EPVA film displays more uniform and smooth morphology, as well as enhanced phase compatibility. PANI is homogeneously distributed in the EPVA matrix on the nanoscale. PANI-g-EPVA displays different morphology at different aniline content. The electrical conductivity corresponds to 7.3 S/cm when only 30% PANI is incorporated into the composites, and then increases up to 20.83 S/cm with further increase in the aniline content. Simultaneously, the tensile strength increases from 35 MPa to 64 MPa. The as-prepared PANI-g-EPVA dispersion can be directly used as the conductive ink or coatings for cellulose fibre paper to prepare flexible conductive paper with high conductivity and mechanical property, which is also suitable for large scalable production.
Curriero, Frank C.; Patz, Jonathan A.; Rose, Joan B.; Lele, Subhash
2001-01-01
Objectives. Rainfall and runoff have been implicated in site-specific waterborne disease outbreaks. Because upward trends in heavy precipitation in the United States are projected to increase with climate change, this study sought to quantify the relationship between precipitation and disease outbreaks. Methods. The US Environmental Protection Agency waterborne disease database, totaling 548 reported outbreaks from 1948 through 1994, and precipitation data of the National Climatic Data Center were used to analyze the relationship between precipitation and waterborne diseases. Analyses were at the watershed level, stratified by groundwater and surface water contamination and controlled for effects due to season and hydrologic region. A Monte Carlo version of the Fisher exact test was used to test for statistical significance. Results. Fifty-one percent of waterborne disease outbreaks were preceded by precipitation events above the 90th percentile (P = .002), and 68% by events above the 80th percentile (P = .001). Outbreaks due to surface water contamination showed the strongest association with extreme precipitation during the month of the outbreak; a 2-month lag applied to groundwater contamination events. Conclusions. The statistically significant association found between rainfall and disease in the United States is important for water managers, public health officials, and risk assessors of future climate change. PMID:11499103
Water-borne protozoa parasites: The Latin American perspective.
Rosado-García, Félix Manuel; Guerrero-Flórez, Milena; Karanis, Gabriele; Hinojosa, María Del Carmen; Karanis, Panagiotis
2017-07-01
Health systems, sanitation and water access have certain limitations in nations of Latin America (LA): typical matters of developing countries. Water is often contaminated and therefore unhealthy for the consumers and users. Information on prevalence and detection of waterborne parasitic protozoa are limited or not available in LA. Only few reports have documented in this field during the last forty years and Brazil leads the list, including countries in South America and Mexico within Central America region and Caribbean islands. From 1979 to 2015, 16 outbreaks of waterborne-protozoa, were reported in Latin American countries. T. gondii and C. cayetanensis were the protozoa, which caused more outbreaks and Giardia spp. and Cryptosporidium spp. were the most frequently found protozoa in water samples. On the other hand, Latin America countries have not got a coherent methodology for detection of protozoa in water samples despite whole LA is highly vulnerable to extreme weather events related to waterborne-infections; although Brazil and Colombia have some implemented laws in their surveillance systems. It would be important to coordinate all surveillance systems in between all countries for early detection and measures against waterborne-protozoan and to establish effective and suitable diagnosis tools according to the country's economic strength and particular needs. Copyright © 2017 Elsevier GmbH. All rights reserved.
Individual and combined effects of multiple pathogens on Pacific treefrogs.
Romansic, John M; Johnson, Pieter T J; Searle, Catherine L; Johnson, James E; Tunstall, Tate S; Han, Barbara A; Rohr, Jason R; Blaustein, Andrew R
2011-08-01
In nature, individual hosts often encounter multiple pathogens simultaneously, which can lead to additive, antagonistic, or synergistic effects on hosts. Synergistic effects on infection prevalence or severity could greatly affect host populations. However, ecologists and managers often overlook the influence of pathogen combinations on hosts. This is especially true in amphibian conservation, even though multiple pathogens coexist within amphibian populations, and several pathogens have been implicated in amphibian population declines and extinctions. Using an amphibian host, Pseudacris regilla (Pacific treefrog), we experimentally investigated interactive effects among three pathogens: the trematode Ribeiroia sp. (hereafter, Ribeiroia), the fungus Batrachochytrium dendrobatidis (hereafter, BD), and the water mold Achlya flagellata. We detected no effects of A. flagellata, but did find effects of Ribeiroia and BD that varied depending on context. Low doses of Ribeiroia caused relatively few malformations, while higher Ribeiroia doses caused numerous deformities dominated by missing and reduced limbs and limb elements. Exposure to low doses of BD accelerated larval host development, despite there being no detectable BD infections, while exposure to higher BD doses caused infection but did not alter developmental rate. Hosts exposed to both Ribeiroia and BD exhibited the highest mortality, although overall evidence of interactive effects of multiple pathogens was limited. We suggest further research on the influence of multi-pathogen assemblages on amphibians, particularly under a variety of ecological conditions and with a wider diversity of hosts and pathogens.
INFECTIOUS DOSE OF NORWALK VIRUS
The Norwalk virus and related viruses (caliciviruses) have been identified as a common cause of waterborne disease. Moreover, there are many outbreaks of waterborne disease every year where the causative agent was never identified, and it is thought that many of these are due to ...
TESTING METHODS FOR DETECTION OF CRYPTOSPORIDIUM SPP. IN WATER SAMPLES
A large waterborne outbreak of cryptosporidiosis in Milwaukee, Wisconsin, U.S.A. in 1993 prompted a search for ways to prevent large scale waterborne outbreaks of protozoan parasitoses. Two principle strategies have emerged: risk assessment leading to appropriate treatment and ...
Problem/Condition: Since 1971, the Centers for Disease Control and Prevention (CDC), the U.S. Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists have maintained a collaborative Waterborne Disease and Outbreak Surveillance System (WBDOS...
Development of a waterborne challenge model for Flavobacterium psychrophilum
USDA-ARS?s Scientific Manuscript database
Flavobacterium psychrophilum is the causative agent of bacterial coldwater disease and can cause significant mortality in salmonid aquaculture. To better evaluate disease prevention or treatment methods for F. psychrophilum in the laboratory, a waterborne challenge model that mimics a natural outbre...
Causes of Outbreaks Associated with Drinking Water in the United States, 1971-2006
Since 1971, the CDC, EPA, and Council of State and Territorial Epidemiologists (CSTE) have maintained the collaborative national Waterborne Disease and Outbreak Surveillance System (WBDOSS) to document waterborne disease outbreaks (WBDOs) reported by local, state, and territorial...
Removal of Waterborne Particles by Electrofiltration: Pilot-Scale Testing
Theoretical analysis using a trajectory approach indicated that in the presence of an external electric field, charged waterborne particles are subject to an additional migration velocity which increases their deposition on the surface of collectors (e.g. sand filter). In this st...
THE EFFECT OF DIETARY ARSENIC ON SWIM-UP RAINBOW TROUT
Two 30-day toxicity tests were conducted in which swim-up rainbow trout were fed live diets of oligochaetes (Lumbriculus variegatus) containing elevated arsenic. Arsenic was incorporated into the diet by exposing oligochaetes to waterborne arsenate (test one) and waterborne ars...
DOT National Transportation Integrated Search
2000-05-15
This report analyzes possibilities for developing an alternative to the present technology of 100% acrylic waterborne (WB) paints used for road delineation. The current market situation is briefly reviewed, and alternatives considered. The requiremen...
Minimizing corrosive action in timber bridges treated with waterborne preservatives
Samuel L. Zelinka; Douglas R. Rammer; James P. Wacker
2007-01-01
This work will briefly review published literature and current research activities on the corrosion of metals in contact with wood treated with waterborne alternatives to CCA. In addition, recommendations to minimize these corrosive effects in timber bridges will be discussed.
Rose, J B; Epstein, P R; Lipp, E K; Sherman, B H; Bernard, S M; Patz, J A
2001-01-01
Exposure to waterborne and foodborne pathogens can occur via drinking water (associated with fecal contamination), seafood (due to natural microbial hazards, toxins, or wastewater disposal) or fresh produce (irrigated or processed with contaminated water). Weather influences the transport and dissemination of these microbial agents via rainfall and runoff and the survival and/or growth through such factors as temperature. Federal and state laws and regulatory programs protect much of the U.S. population from waterborne disease; however, if climate variability increases, current and future deficiencies in areas such as watershed protection, infrastructure, and storm drainage systems will probably increase the risk of contamination events. Knowledge about transport processes and the fate of microbial pollutants associated with rainfall and snowmelt is key to predicting risks from a change in weather variability. Although recent studies identified links between climate variability and occurrence of microbial agents in water, the relationships need further quantification in the context of other stresses. In the marine environment as well, there are few studies that adequately address the potential health effects of climate variability in combination with other stresses such as overfishing, introduced species, and rise in sea level. Advances in monitoring are necessary to enhance early-warning and prevention capabilities. Application of existing technologies, such as molecular fingerprinting to track contaminant sources or satellite remote sensing to detect coastal algal blooms, could be expanded. This assessment recommends incorporating a range of future scenarios of improvement plans for current deficiencies in the public health infrastructure to achieve more realistic risk assessments. PMID:11359688
Rose, J B; Epstein, P R; Lipp, E K; Sherman, B H; Bernard, S M; Patz, J A
2001-05-01
Exposure to waterborne and foodborne pathogens can occur via drinking water (associated with fecal contamination), seafood (due to natural microbial hazards, toxins, or wastewater disposal) or fresh produce (irrigated or processed with contaminated water). Weather influences the transport and dissemination of these microbial agents via rainfall and runoff and the survival and/or growth through such factors as temperature. Federal and state laws and regulatory programs protect much of the U.S. population from waterborne disease; however, if climate variability increases, current and future deficiencies in areas such as watershed protection, infrastructure, and storm drainage systems will probably increase the risk of contamination events. Knowledge about transport processes and the fate of microbial pollutants associated with rainfall and snowmelt is key to predicting risks from a change in weather variability. Although recent studies identified links between climate variability and occurrence of microbial agents in water, the relationships need further quantification in the context of other stresses. In the marine environment as well, there are few studies that adequately address the potential health effects of climate variability in combination with other stresses such as overfishing, introduced species, and rise in sea level. Advances in monitoring are necessary to enhance early-warning and prevention capabilities. Application of existing technologies, such as molecular fingerprinting to track contaminant sources or satellite remote sensing to detect coastal algal blooms, could be expanded. This assessment recommends incorporating a range of future scenarios of improvement plans for current deficiencies in the public health infrastructure to achieve more realistic risk assessments.
Flöthe, Carla R.; John, Uwe; Molis, Markus
2014-01-01
Some seaweed species have been shown to release water-borne cues after herbivore attack, for example, to attract natural enemies of the herbivore. These cues may also be sensed by neighboring seaweeds and used to adjust their defenses in anticipation of a possible herbivore attack. Several studies indicated information transfer between seaweed individuals in the past, including the brown seaweed Fucus vesiculosus. Previous work showed induction of defenses in F. vesiculosus in response to water-borne cues released by isopod-grazed conspecifics. In contrast, another study on induced responses after exposure to cues from isopod-grazed neighbors using the same seaweed species yielded contradictory results. This study reassessed the ability of F. vesiculosus individuals to sense water-borne cues released by isopod-grazed neighbors in a series of experiments that monitored F. vesiculosus palatability in response to direct grazing by Idotea baltica and water-borne cues from isopod-grazed neighbors relative to unmanipulated seaweed pieces. Two-choice feeding assays were conducted with both fresh and reconstituted seaweed pieces. Direct grazing by I. baltica induced a chemical defense in F. vesiculosus, confirming results of previous studies. In contrast, evidence for increased herbivore resistance in seaweed pieces that were located downstream of isopod-grazed F. vesiculosus could not be provided. The lack of defense induction in response to grazing of conspecific neighbors may be explained by the environmental conditions and the scattered distribution of F. vesiculosus individuals in the intertidal zone of Helgoland, which may render resource investment in the emission and/or response to water-borne cues at this site unprofitable. PMID:25279662
NASA Astrophysics Data System (ADS)
Kuo, C.; Hsu, B.; Shen, T.; Tseng, S.; Tsai, J.; Huang, K.; Kao, P.; Chen, J.
2013-12-01
Salmonella spp. is a common water-borne pathogens and its genus comprises more than 2,500 serotypes. Major pathogenic genotypes which cause typhoid fever, enteritis and other intestinal-type diseases are S. Typhimurium, S. Enteritidis, S. Stanley, S. Agona, S.Albany, S. Schwarzengrund, S. Newport, S. Choleraesuis, and S. Derby. Hence, the identification of the serotypes of Salmonella spp. is important. In the present study, the analytical procedures include direct concentration method, non-selective pre-enrichment method and selective enrichment method of Salmonella spp.. Both selective enrichment method and cultured bacteria were detected with specific primers of Salmonella spp. by polymerase chain reaction (PCR). At last, the serotypes of Salmonella were confirmed by using MLST (multilocus sequence typing) with aroC, dnaN, hemD, hisD, purE, sucA, thrA housekeeping genes to identify the strains of positive samples. This study contains 121 samples from three different types of water sources including the drinking water (51), streams (45), and swine wastewater (25). Thirteen samples with positive invA gene are separated from culture method. The strains of these positive samples which identified from MLST method are S. Albany, S. Typhimurium, S. Newport, S. Bareilly, and S. Derby. Some of the serotypes, S. Albany, S. Typhimurium and S. Newport, are highly pathogenic which correlated to human diarrhea. In our results, MLST is a useful method to identify the strains of Salmonella spp.. Keywords: Salmonella, PCR, MLST.
Brinkman, Nichole E.; Haugland, Richard A.; Wymer, Larry J.; Byappanahalli, Muruleedhara N.; Whitman, Richard L.; Vesper, Stephen J.
2003-01-01
Quantitative PCR (QPCR) technology, incorporating fluorigenic 5′ nuclease (TaqMan) chemistry, was utilized for the specific detection and quantification of six pathogenic species of Candida (C. albicans, C. tropicalis, C. krusei, C. parapsilosis, C. glabrata and C. lusitaniae) in water. Known numbers of target cells were added to distilled and tap water samples, filtered, and disrupted directly on the membranes for recovery of DNA for QPCR analysis. The assay's sensitivities were between one and three cells per filter. The accuracy of the cell estimates was between 50 and 200% of their true value (95% confidence level). In similar tests with surface water samples, the presence of PCR inhibitory compounds necessitated further purification and/or dilution of the DNA extracts, with resultant reductions in sensitivity but generally not in quantitative accuracy. Analyses of a series of freshwater samples collected from a recreational beach showed positive correlations between the QPCR results and colony counts of the corresponding target species. Positive correlations were also seen between the cell quantities of the target Candida species detected in these analyses and colony counts of Enterococcus organisms. With a combined sample processing and analysis time of less than 4 h, this method shows great promise as a tool for rapidly assessing potential exposures to waterborne pathogenic Candida species from drinking and recreational waters and may have applications in the detection of fecal pollution.
Lee, Cheonghoon; Agidi, Senyo; Marion, Jason W; Lee, Jiyoung
2012-08-01
The genus Arcobacter has been associated with human illness and fecal contamination by humans and animals. To better characterize the health risk posed by this emerging waterborne pathogen, we investigated the occurrence of Arcobacter spp. in Lake Erie beach waters. During the summer of 2010, water samples were collected 35 times from the Euclid, Villa Angela, and Headlands (East and West) beaches, located along Ohio's Lake Erie coast. After sample concentration, Arcobacter was quantified by real-time PCR targeting the Arcobacter 23S rRNA gene. Other fecal genetic markers (Bacteroides 16S rRNA gene [HuBac], Escherichia coli uidA gene, Enterococcus 23S rRNA gene, and tetracycline resistance genes) were also assessed. Arcobacter was detected frequently at all beaches, and both the occurrence and densities of Arcobacter spp. were higher at the Euclid and Villa Angela beaches (with higher levels of fecal contamination) than at the East and West Headlands beaches. The Arcobacter density in Lake Erie beach water was significantly correlated with the human-specific fecal marker HuBac according to Spearman's correlation analysis (r = 0.592; P < 0.001). Phylogenetic analysis demonstrated that most of the identified Arcobacter sequences were closely related to Arcobacter cryaerophilus, which is known to cause gastrointestinal diseases in humans. Since human-pathogenic Arcobacter spp. are linked to human-associated fecal sources, it is important to identify and manage the human-associated contamination sources for the prevention of Arcobacter-associated public health risks at Lake Erie beaches.
Sokolova, Ekaterina; Petterson, Susan R; Dienus, Olaf; Nyström, Fredrik; Lindgren, Per-Eric; Pettersson, Thomas J R
2015-09-01
Norovirus contamination of drinking water sources is an important cause of waterborne disease outbreaks. Knowledge on pathogen concentrations in source water is needed to assess the ability of a drinking water treatment plant (DWTP) to provide safe drinking water. However, pathogen enumeration in source water samples is often not sufficient to describe the source water quality. In this study, the norovirus concentrations were characterised at the contamination source, i.e. in sewage discharges. Then, the transport of norovirus within the water source (the river Göta älv in Sweden) under different loading conditions was simulated using a hydrodynamic model. Based on the estimated concentrations in source water, the required reduction of norovirus at the DWTP was calculated using quantitative microbial risk assessment (QMRA). The required reduction was compared with the estimated treatment performance at the DWTP. The average estimated concentration in source water varied between 4.8×10(2) and 7.5×10(3) genome equivalents L(-1); and the average required reduction by treatment was between 7.6 and 8.8 Log10. The treatment performance at the DWTP was estimated to be adequate to deal with all tested loading conditions, but was heavily dependent on chlorine disinfection, with the risk of poor reduction by conventional treatment and slow sand filtration. To our knowledge, this is the first article to employ discharge-based QMRA, combined with hydrodynamic modelling, in the context of drinking water. Copyright © 2015 Elsevier B.V. All rights reserved.
Tracing the source of campylobacteriosis.
Wilson, Daniel J; Gabriel, Edith; Leatherbarrow, Andrew J H; Cheesbrough, John; Gee, Steven; Bolton, Eric; Fox, Andrew; Fearnhead, Paul; Hart, C Anthony; Diggle, Peter J
2008-09-26
Campylobacter jejuni is the leading cause of bacterial gastro-enteritis in the developed world. It is thought to infect 2-3 million people a year in the US alone, at a cost to the economy in excess of US $4 billion. C. jejuni is a widespread zoonotic pathogen that is carried by animals farmed for meat and poultry. A connection with contaminated food is recognized, but C. jejuni is also commonly found in wild animals and water sources. Phylogenetic studies have suggested that genotypes pathogenic to humans bear greatest resemblance to non-livestock isolates. Moreover, seasonal variation in campylobacteriosis bears the hallmarks of water-borne disease, and certain outbreaks have been attributed to contamination of drinking water. As a result, the relative importance of these reservoirs to human disease is controversial. We use multilocus sequence typing to genotype 1,231 cases of C. jejuni isolated from patients in Lancashire, England. By modeling the DNA sequence evolution and zoonotic transmission of C. jejuni between host species and the environment, we assign human cases probabilistically to source populations. Our novel population genetics approach reveals that the vast majority (97%) of sporadic disease can be attributed to animals farmed for meat and poultry. Chicken and cattle are the principal sources of C. jejuni pathogenic to humans, whereas wild animal and environmental sources are responsible for just 3% of disease. Our results imply that the primary transmission route is through the food chain, and suggest that incidence could be dramatically reduced by enhanced on-farm biosecurity or preventing food-borne transmission.
A model for estimating pathogen variability in shellfish and predicting minimum depuration times.
McMenemy, Paul; Kleczkowski, Adam; Lees, David N; Lowther, James; Taylor, Nick
2018-01-01
Norovirus is a major cause of viral gastroenteritis, with shellfish consumption being identified as one potential norovirus entry point into the human population. Minimising shellfish norovirus levels is therefore important for both the consumer's protection and the shellfish industry's reputation. One method used to reduce microbiological risks in shellfish is depuration; however, this process also presents additional costs to industry. Providing a mechanism to estimate norovirus levels during depuration would therefore be useful to stakeholders. This paper presents a mathematical model of the depuration process and its impact on norovirus levels found in shellfish. Two fundamental stages of norovirus depuration are considered: (i) the initial distribution of norovirus loads within a shellfish population and (ii) the way in which the initial norovirus loads evolve during depuration. Realistic assumptions are made about the dynamics of norovirus during depuration, and mathematical descriptions of both stages are derived and combined into a single model. Parameters to describe the depuration effect and norovirus load values are derived from existing norovirus data obtained from U.K. harvest sites. However, obtaining population estimates of norovirus variability is time-consuming and expensive; this model addresses the issue by assuming a 'worst case scenario' for variability of pathogens, which is independent of mean pathogen levels. The model is then used to predict minimum depuration times required to achieve norovirus levels which fall within possible risk management levels, as well as predictions of minimum depuration times for other water-borne pathogens found in shellfish. Times for Escherichia coli predicted by the model all fall within the minimum 42 hours required for class B harvest sites, whereas minimum depuration times for norovirus and FRNA+ bacteriophage are substantially longer. Thus this study provides relevant information and tools to assist norovirus risk managers with future control strategies.
Microbes in Beach Sands: Integrating Environment, Ecology and Public Health
Whitman, Richard; Harwood, Valerie J.; Edge, Thomas A.; Nevers, Meredith; Byappanahalli, Muruleedhara; Vijayavel, Kannappan; Brandão, João; Sadowsky, Michael J.; Alm, Elizabeth Wheeler; Crowe, Allan; Ferguson, Donna; Ge, Zhongfu; Halliday, Elizabeth; Kinzelman, Julie; Kleinheinz, Greg; Przybyla-Kelly, Kasia; Staley, Christopher; Staley, Zachery; Solo-Gabriele, Helena M.
2014-01-01
SUMMARY Beach sand is a habitat that supports many microbes, including viruses, bacteria, fungi and protozoa (micropsammon). The apparently inhospitable conditions of beach sand environments belie the thriving communities found there. Physical factors, such as water availability and protection from insolation; biological factors, such as competition, predation, and biofilm formation; and nutrient availability all contribute to the characteristics of the micropsammon. Sand microbial communities include autochthonous species/phylotypes indigenous to the environment. Allochthonous microbes, including fecal indicator bacteria (FIB) and waterborne pathogens, are deposited via waves, runoff, air, or animals. The fate of these microbes ranges from death, to transient persistence and/or replication, to establishment of thriving populations (naturalization) and integration in the autochthonous community. Transport of the micropsammon within the habitat occurs both horizontally across the beach, and vertically from the sand surface and ground water table, as well as at various scales including interstitial flow within sand pores, sediment transport for particle-associated microbes, and the large-scale processes of wave action and terrestrial runoff. The concept of beach sand as a microbial habitat and reservoir of FIB and pathogens has begun to influence our thinking about human health effects associated with sand exposure and recreational water use. A variety of pathogens have been reported from beach sands, and recent epidemiology studies have found some evidence of health risks associated with sand exposure. Persistent or replicating populations of FIB and enteric pathogens have consequences for watershed/beach management strategies and regulatory standards for safe beaches. This review summarizes our understanding of the community structure, ecology, fate, transport, and public health implications of microbes in beach sand. It concludes with recommendations for future work in this vastly under-studied area. PMID:25383070
Wilkes, Graham; Brassard, Julie; Edge, Thomas A.; Gannon, Victor; Gottschall, Natalie; Jokinen, Cassandra C.; Jones, Tineke H.; Khan, Izhar U. H.; Marti, Romain; Sunohara, Mark D.; Topp, Edward
2014-01-01
Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp. and Arcobacter spp. in the CTD watershed. There were no instances where there were significantly higher quantitative loadings of any microbial target in the CTD watershed, except for F-specific DNA (F-DNA) and F-RNA coliphages, perhaps as a result of fecal inputs from a hobby farm independent of the drainage practice treatments. There was lower loading of the ruminant marker in the CTD watershed in relation to the UCTD system, and results were significant at the level P = 0.06. The odds of Salmonella spp. occurring increased when a ruminant marker was present relative to when the ruminant marker was absent, yet for Arcobacter spp., the odds of this pathogen occurring significantly decreased when a ruminant marker was present relative to when the ruminant marker was absent (but increased when a wildlife marker was present relative to when the wildlife marker was absent). Interestingly, the odds of norovirus GII (associated with human and swine) occurring in water increased significantly when a ruminant marker was present relative to when a ruminant marker was absent. Overall, this study suggests that fecal pollution from tile-drained fields to stream could be reduced by CTD utilization. PMID:24727274
Background: Salivary antibody is a promising non-invasive biomarker of specific infections. This exploratory study used an in-house salivary immunoassay to assess waterborne transmission of Cryptosporidium. Methods: Families with children were followed during summer-early wint...
IMPROVING DETECTION METHODS FOR ENTERIC WATERBORNE VIRUSES
Waterborne viruses are a significant cause of illness, both within the US and worldwide. These illnesses can occur as the result of outbreaks, potentially affecting hundreds or thousands of people, or as a part of a background level of endemic infection. While many of these out...
CONTROL OF MICROBES AND DBPS IN DRINKING WATER: AN OVERVIEW
Historically drinking water utilities in the United States (U.S.) have played a major role in protecting public health through the reduction of waterborne disease. These reductions in waterborne disease outbreaks were brought about by the use of sand filtration, disinfection and...
TESTING METHODS FOR DETECTION OF CRYPTOSPORIDIUM SPP. IN WATER SAMPLES
A large waterborne outbreak of cryptosporidiosis in Milwaukee, Wisconsin, U.S.A. in 1993 prompted a search for ways to prevent large-scale waterborne outbreaks of protozoan parasitoses. Methods for detecting Cryptosporidium parvum play an integral role in strategies that lead to...
Research notes : pavement markings using waterborne paint and Visibeads in Region 2.
DOT National Transportation Integrated Search
1995-01-01
In order to address the problems associated with solvent-borne patins, ODOT Region 2 staff bought sufficient waterborne paint to place approximately 760 linear miles of stripes. This enabled the Region staff to evaluate state-of-the-art materials and...
WATERBORNE OUTBREAKS CAUSED BY DISTRIBUTION SYSTEM DEFICIENCIES IN THE UNITED STATES
Distribution system contamination has caused a significant number of waterborne outbreaks in the United States. The number of illnesses in a distribution-system outbreak can be quite large, and illness can be severe resulting in hospitalization and sometimes death. During t...