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Outbreaks of waterborne diseases continue to appear worldwide despite efforts expended for safe water quality. The causative agents are diversified between bacteria, fungi, viruses, and parasites, as these microoganisms constitute the crucial agents that determine the microbial quality of water. The problems caused by pathogens are not only health issues but also the high costs of prevention and treatment. Accurate determination and identification of pathogens and rapid results from water quality monitoring are key factors in effective decision making in order to achieve good water quality and prevent waterborne outbreaks. In addition to the conventional detection and control techniques for waterborne pathogens, new powerful, sensitive, and reproducible instruments ranging in size from 1 to 100 nm are under development to detect pathogenic contaminants in water and improve its quality. This chapter first discusses the occurrence of waterborne pathogens and associated pathologies; it then describes the main nanocomposites and their operating principles for the detection and control of waterborne pathogens.

This chapter provides an introduction to waterborne pathogens, which can be divided into three main categories; viruses, bacteria and parasites, the latter of which are comprised of protozoa and helminths. Each category comprises a section within the chapter. The World Health Organisation has compiled a List of Relevant Waterborne Pathogens, which considers human health risk based upon factors such as persistence in the environment, infectious dose and resistance to disinfection methods. An adaptation of this list forms the basis of this chapter. Each category of waterborne pathogen is discussed in turn, with examples given of those pathogens considered most problematic. In general, the focus is on those pathogens for which the route of disease transmission occurs through ingestion of water. Where available, information is presented regarding the disease caused by each of these pathogens in terms of symptoms, prevalence and treatment. Additionally, information is given on the number of different species of each pathogen, their size and appearance. Furthermore, mention of recent waterborne outbreaks attributed to each of the pathogens is given.

Pathogenic microorganisms are the primary agents of waterborne disease that is responsible for high global mortality rate. Although conventional disinfectants are effective in inactivating common waterborne pathogens, they still bear a risk of generating harmful disinfection by-products. Since its discovery in 1991, carbon nanotube (CNT) has been renowned for its high adsorption capacity and has been utilized to remove a wide range of contaminants including biological contaminants in water. In recent times, antimicrobial activity of CNTs has been also documented in a number of studies that have paved the way for their applications in water disinfection systems. This chapter reviews biocidal effect and adsorption ability of two types of CNTs: single-walled carbon nanotubes and multi-walled carbon nanotubes, as well as some of their composites with other materials such as metal nanoparticles, polymers, and other antimicrobial agents. Toxicological and environmental concerns of CNTs and future challenges that still limit the optimal utilization of CNTs in waterborne pathogen control are also discussed.

Accurate and timely assessment of pathogens in water is the key factor for proper community healthcare, as well as in administrative decision-making toward the best water treatment process, distribution infrastructure, and prevention of waterborne outbreaks. Detection and identification of a microbial species in a short time with high specificity is indeed a very complex and challenging task. In last few years, there has been rapid progress in the field of sensing techniques for the detection of pathogens. The golden handshake between the advances in molecular materials and cutting-edge electronics has paved way for the development of platforms for real time, and continuous detection methods are emerging out with excellent sensitivity and reproducibility. This chapter presents an overview of variety of biorecognition molecules and transduction methodologies. The molecular materials employed are reviewed, with mode of actions in selected cases. The discussion focuses on the molecular techniques for detection of waterborne pathogens.

Water is the most crucial commodity for life support process in organism. There are various natural and anthropogenic factors that affect the basic physical, chemical, and biological properties of natural water. Among them waterborne pathogens and chemical contaminants are major concerns for public health on local, regional, and global scale, not only with respect to morbidity and mortality but by the high cost of their prevention and treatment. The contamination of water through bacteria, virus, protozoa, and some chemical species are major concerns for waterborne pathogen. This chapter provides a brief overview on conventional chemical treatment technique for wastewater treatment. In accordance with this method, some of the conventional treatment processes are based on coagulation-flocculation, chemical precipitation technique, ion exchange, adsorption, membrane filtration, and electrochemical treatment followed by disinfection used in wastewater treatment, as well as advanced chemical oxidation process such as ozonation, ultraviolet radiation, and chlorination for waterborne pathogen treatment.

Background 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. Method 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). Results 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. Conclusions 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.

Most of the global outbreaks of waterborne parasitic protozoa have been reported in regions with established surveillance and reporting systems such as Australia, Europe, New Zealand, and North America. Given that only an estimated 1% of these outbreaks have occurred in Asia, it is evident that there is a paucity of information from this region where organised mechanisms of documentation of parasitic infections or waterborne outbreaks are lacking. This review attempts to provide an overview of the available data and studies on waterborne parasite occurrences among the Association of Southeast Asian Nations (ASEAN) which comprises of the ten member states (i.e., Brunei Darussalam, Cambodia, Indonesia, Lao People's Democratic Republic (PDR), Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Vietnam) with the aims of identifying some directions on how to progress., Highlights • 1% of global outbreaks of waterborne parasitic protozoa have been reported in Asia. • Studies on occurrence of waterborne parasites are limited in ASEAN. • Overview of the available data aims to identify the directions forward.

Cryptosporidiumis an important genus of emerging enteropathogens responsible for waterborne outbreaksworldwide. This parasite has a robust infective form (oocyst), which is highly resistant to the environmentalconditions and to the conventional disinfection treatments of water. This work evaluates for thefirst time thephoto-Fenton process againstCryptosporidium parvum.For that, a factorial design was used to study the com-bined effects of the Fe2+/H2O2concentration (5/10, 10/20 and 20/50 mg L−1), pH (3, 5.5 and 8) and exposuretime (2, 4 and 6 h) on the oocyst survival in distilled water under natural sunlight. The oocyst viability wasdetermined by inclusion/exclusion of thefluorogenic vital dye propidium iodide. The variables Fe2+/H2O2concentration and exposure time showed statistically significant effects on the oocyst viability, as did the in-teraction of pH with Fe2+/H2O2concentration. The maximum oocyst inactivation rates corresponded to thecombination of the highest concentration of Fe2+/H2O2(20/50 mg L−1), the lowest pH value (3) and longestexposure times (4 and 6 h) (3.68 ± 1.38% and 6.39 ± 2.65%, respectively,vs91.67 ± 3.63%, initial oocystviability). Although further studies are needed to evaluate the influence of the water matrix and optimize thephoto-Fenton process, the results obtained demonstrate the efficacy of this advanced oxidation process againstC.parvumoocysts. The inactivation of this enteropathogen would probably ensure elimination of other less re-sistant infectious agents, providing an appropriate protection for the environment and, consequently, for humanand animal health This Special Issue is dedicated to honor the retirement of Prof. CésarPulgarin at the Swiss Federal Institute of Technology (EPFL,Switzerland), a keyfigure in the area of Catalytic Advanced OxidationProcesses. This work was supported by the European Union ́s Horizon2020 Research and Innovation [grant number 688928] SI

More than 250 different foodborne diseases have been described to date, annually affecting about one-third of the world's population. The incidence of foodborne diseases has been underreported and underestimated, and the asymptomatic presentation of some of the illnesses, worldwide heterogeneities in reporting, and the alternative transmission routes of certain pathogens are among the factors that contribute to this. Globalization, centralization of the food supply, transportation of food products progressively farther from their places of origin, and the multitude of steps where contamination may occur have made it increasingly challenging to investigate foodborne and waterborne outbreaks. Certain foodborne pathogens may be transmitted directly from animals to humans, while others are transmitted through vectors, such as insects, or through food handlers, contaminated food products or food-processing surfaces, or transfer from sponges, cloths, or utensils. Additionally, the airborne route may contribute to the transmission of certain foodborne pathogens. Complicating epidemiological investigations, multiple transmission routes have been described for some foodborne pathogens. Two types of transmission barriers, primary and secondary, have been described for foodborne pathogens, each of them providing opportunities for preventing and controlling outbreaks. Primary barriers, the most effective sites of prophylactic intervention, prevent pathogen entry into the environment, while secondary barriers prevent the multiplication and dissemination of pathogens that have already entered the environment. Understanding pathogen dynamics, monitoring transmission, and implementing preventive measures are complicated by the phenomenon of superspreading, which refers to the concept that, at the level of populations, a minority of hosts is responsible for the majority of transmission events.

This chapter concludes the book on waterborne pathogen monitoring, summarizing the main findings from the other chapters and looking forward to the future of waterborne pathogen monitoring. A background and overview of waterborne pathogens and the need for monitoring is given. Subsequently, the main findings of each chapter, summarizing the latest research literature, are discussed in the areas of sample processing and detection. Finally, a future perspective is provided. Here, suggestions of required developments and future research areas are discussed. The future is challenging to predict, but it seems clear a range of methods, offering different advantages, will be needed to meet the future requirements of waterborne pathogen monitoring. Many of the technologies discussed in the book offer a high degree of potential and there is unlikely to be one universal solution, given the wide range of pathogens to be detected and the different reasons why monitoring may be undertaken.

This chapter considers new technology for waterborne pathogen detection from a wider perspective. It offers deeper insight into how regulations impact the testing regimes in different countries and the view of the water industry itself toward new technologies. It highlights the priority pathogens from a market perspective and detection methods from a public health perspective. The final section of the chapter concentrates on the challenges involved in translating new detection technologies from lab-scale through scale-up and performance validation to widespread acceptance and adoption within the water industry.

This chapter discusses Hepatitis A virus (HAV) basic microbiology, natural history of the organism, clinical features, and epidemiology of waterborne outbreaks, including transmission, distribution and persistence in the environment, removal by treatment and waterborne outbreaks. Many hepatitis A viral infections, especially in children, are asymptomatic. The severity of the symptoms is age-related and infection in adults is more severe. HAV has been found in sewage, surface water sources, ground water sources and in food, especially shellfish. Hepatitis A is spread through faecal–oral contact; therefore, it may be spread by drinking polluted water, by contact with recreational water or by consuming infected shellfish. It is also transmitted by close person-to-person contact. Many waterborne outbreaks have been linked to drinking water and recreational water contact.

This chapter discusses Rotaviruses, basic microbiology, natural history of the organism, clinical features, and epidemiology of waterborne outbreaks, including transmission, distribution and persistence in the environment, removal by treatment and waterborne outbreaks. Rotaviruses are relatively large icosahedral virus particles with a triple layer of protein. Rotavirus is the most common cause of severe diarrhoea among children in developing countries. This can become a life-threatening illness if severe dehydration develops. Other symptoms can include vomiting and fever, especially in young children. The development of vaccines has greatly decreased the incidence of rotavirus gastroenteritis among children in developed countries. Transmission is by the faecal–oral route, either directly from person-to-person or via fomites. Zoonotic transmission of rotaviruses, from wild animals, pets and livestock animals has been documented to occur. Rotavirus has been detected in sewage, surface waters and ground water. Rotaviruses have been implicated in waterborne outbreaks, but the viruses are typically detected in clinical specimens, rather than in the water.

This chapter discusses Astrovirus, basic microbiology, natural history of the organism, clinical features, and epidemiology of waterborne outbreaks, including transmission, distribution and persistence in the environment, removal by treatment, and waterborne outbreaks. The role of Astrovirus in enteric disease has been less understood. Astroviruses are endemic in most communities world-wide and mostly infect young children and babies, although they have been associated with disease in the elderly. They appear to have a very low pathogenicity for adults. Generally, astroviruses cause only a mild or symptomless infection, but reported incidences are second only to rotaviruses as causing infantile gastroenteritis. Person-to-person spread by the fecal–oral route is thought to be the most common route of transmission. Food, water and fomites have been implicated in Astrovirus disease, which suggests that astroviruses persist in the environment. One outbreak caused by Astrovirus in a public water supply has been reported. There is evidence to suggest that zoonotic transmission of Astrovirus, or recombination between human and animal strains of astrovirus, can occur.

Astroviruses are one of the leading causes of viral gastroenteritis in the young, elderly, and immunocompromised. Although the prevalence is unknown, they are also thought to be associated with food- and waterborne outbreaks of acute diarrhea. This chapter will introduce readers to astroviruses, including the extensive diversity in humans; summarize what is known about food- and waterborne outbreaks; and conclude with where the field needs to go to better understand this important virus in food safety.

Community-associated foodborne or waterborne outbreaks are rather common. Waterborne outbreaks often occur in communities where groundwater is used as a source and is distributed nondisinfected. If it is microbiologically contaminated, the barriers preventing distribution of contaminated tap water are minor. Local public health authorities require strategies and plans to clarify how to manage future waterborne outbreaks and prevent such incidents. The case deals with a waterborne outbreak in a small community in Finland, requisition of patient and epidemiological data, and how the outbreak was identified and controlled.

This chapter discusses Mycobacterium, basic microbiology, origin and taxonomy, metabolism and physiology, clinical features, pathogenicity and virulence, treatment, survival in the environment, methods of detection, epidemiology of waterborne outbreaks, and finally, risk assessment. Mycobacteria are Gram-positive, slender, non-motile, non-spore forming, rodshaped bacilli, which may appear bent or curved. Cells are pleomorphic, ranging from a coccoid form to long slender rods. Mycobacterium, have been known to be opportunistic pathogens of many disseminated diseases with patients dying of AIDS, skin lesions such as post-injection abscesses, swimming pool granulomas and Buruli ulcers, tuberculosis-like lesions and also lympadenitis following infection. Mycobacterium avium complex (MAC) have been isolated world-wide from all natural water systems, including marine water and soil. Man-made habitats, such as water distribution systems, are colonized by considerably high numbers of mycobacterial species. MAC generally causes three different types of diseases in humans: pulmonary disease, cervical lymphadenitis, and disseminated MAC. Routes of exposure are ingestion through the gastrointestinal tract and the inhalation of aerosols. Some believe the latter is responsible for more transmission than the former.

Publisher Summary The surveillance of infectious intestinal diseases is a chief public health measure that can be employed to comprehend the epidemiology of diarrheal disease. It is a process of routinely collecting information on the pathogens being detected in laboratories. This chapter presents a paper which demonstrates the use of a progression of approaches to the surveillance of cryptosporidiosis, using different approaches as new information becomes available. The majority of cases of cryptosporidiosis have no identifiable cause but surveillance of waterborne outbreaks has identified drinking water and recreational water as central routes of transmission along with overseas travel and animal contact. The progression of surveillance approaches has been useful in elucidating the epidemiology of cryptosporidiosis through building on the knowledge gained from previous approaches.

Publisher Summary This chapter presents a study on the detection of Cryptosporidium oocysts in water matrices. Many waterborne outbreaks of cryptosporidiosis have occurred recently because of which the past decade has seen a gigantic effort expended on the development of methods to detect Cryptosporidium parvum oocysts in source and finished water. Initial analyses for C. parvum oocysts were based on methods developed for detecting Giardia cysts in water. In the case of Cryptosporidium, recovery rates ranged from 0% to 11% in seeded samples. Method 1622 for Cryptosporidium was developed using off the shelf reagents and equipment in an attempt to improve on oocyst recovery rates. The recovery results for the Method 1622 only average around 38%. A number of factors are now known to compromise oocyst recovery. Most methods are dependent on commercially prepared products and reagents like C. parvum oocysts, antibody stains, immunomagnetic separation kits, and filters. Current practice calls for C. parvum oocysts to be used in quality assurance and control studies associated with all recognized Cryptosporidium oocyst detection methods. Demand has increased significantly over the past 10 years for oocysts needed to study physical removal and chemical inactivation of these parasites.

Publisher Summary This chapter draws heavily on the molecular epidemiology of human cryptosporidiosis. Cryptosporidiosis is a common cause of diarrheal diseases in humans. In developing countries, Cryptosporidium infections occur typically in children younger than 5 years old, with peak occurrence of infections and diarrhea in children less than 2 years old. Children can have multiple episodes of cryptosporidiosis, implying that acquired immunity against Cryptosporidium infection is short-lived or incomplete. In industrialized countries, epidemic cryptosporidiosis can occur in adults via foodborne or waterborne outbreaks. Clinical manifestations of cryptosporidiosis vary with age and immunologic status. In children residing in endemic areas, the major symptom is diarrhea, which occurs only in a subset of infected persons. In outbreak settings, immune-competent adults may have voluminous but self-limiting diarrhea, with or without abdominal cramps, fatigue, vomiting, and other symptoms. In immunodeficient humans, cryptosporidiosis can be associated with chronic, potentially life-threatening diarrhea. Because of the ability of Cryptosporidium parasites to infect humans and a broad variety of animals and because of the ubiquitous presence of Cryptosporidium oocysts in the environment, humans can acquire Cryptosporidium infections through several transmission routes. This chapter elaborates on the aforementioned details along with accounts on various molecular tools used, species and genotypes of Cryptosporidium in humans, and molecular epidemiology of epidemic cryptosporidiosis.