Legionella Contamination In Water Environment

Legionella spp. are ubiquitous microorganisms that are widely distributed in aquatic environments. Water systems of large buildings, such as hospitals, hotels, and rental units are often contaminated by legionellae and various parameters such as physical, chemical, and microbial building water system characteristics can influence Legionella occurrence. A range of physical and chemical disinfection methods have been proposed to control Legionella contamination; however, to date, the most effective procedures have not been defined. There is a need to survey legionellae in water systems to prevent legionellosis. Although the assessment of L. pneumophila in water is typically performed by culture isolation on selective media, it has several limits. For this reason, alternative tools for rapid, sensitive, and specific detection of Legionella in water samples have been proposed. In order to increase knowledge on different aspects of Legionella contamination in the water environment, this book gathers research studies related to the occurrence of Legionella in water systems of different environments; the role of different factors that can influence the Legionella contamination, as well as the advantages and disadvantages of different methodological approaches.

Legionnaires' disease, a pneumonia caused by the Legionella bacterium, is the leading cause of reported waterborne disease outbreaks in the United States. Legionella occur naturally in water from many different environmental sources, but grow rapidly in the warm, stagnant conditions that can be found in engineered water systems such as cooling towers, building plumbing, and hot tubs. Humans are primarily exposed to Legionella through inhalation of contaminated aerosols into the respiratory system. Legionnaires' disease can be fatal, with between 3 and 33 percent of Legionella infections leading to death, and studies show the incidence of Legionnaires' disease in the United States increased five-fold from 2000 to 2017. Management of Legionella in Water Systems reviews the state of science on Legionella contamination of water systems, specifically the ecology and diagnosis. This report explores the process of transmission via water systems, quantification, prevention and control, and policy and training issues that affect the incidence of Legionnaires' disease. It also analyzes existing knowledge gaps and recommends research priorities moving forward.

Legionella spp. are ubiquitous microorganisms that are widely distributed in aquatic environments. Water systems of large buildings, such as hospitals, hotels, and rental units are often contaminated by legionellae and various parameters such as physical, chemical, and microbial building water system characteristics can influence Legionella occurrence. A range of physical and chemical disinfection methods have been proposed to control Legionella contamination; however, to date, the most effective procedures have not been defined. There is a need to survey legionellae in water systems to prevent legionellosis. Although the assessment of L. pneumophila in water is typically performed by culture isolation on selective media, it has several limits. For this reason, alternative tools for rapid, sensitive, and specific detection of Legionella in water samples have been proposed. In order to increase knowledge on different aspects of Legionella contamination in the water environment, this book gathers research studies related to the occurrence of Legionella in water systems of different environments; the role of different factors that can influence the Legionella contamination, as well as the advantages and disadvantages of different methodological approaches.

Legionnaires' disease, a pneumonia caused by the Legionella bacterium, is the leading cause of reported waterborne disease outbreaks in the United States. Legionella occur naturally in water from many different environmental sources, but grow rapidly in the warm, stagnant conditions that can be found in engineered water systems such as cooling towers, building plumbing, and hot tubs. Humans are primarily exposed to Legionella through inhalation of contaminated aerosols into the respiratory system. Legionnaires' disease can be fatal, with between 3 and 33 percent of Legionella infections leading to death, and studies show the incidence of Legionnaires' disease in the United States increased five-fold from 2000 to 2017. Management of Legionella in Water Systems reviews the state of science on Legionella contamination of water systems, specifically the ecology and diagnosis. This report explores the process of transmission via water systems, quantification, prevention and control, and policy and training issues that affect the incidence of Legionnaires' disease. It also analyzes existing knowledge gaps and recommends research priorities moving forward.

This deadly pneumonia has a high mortality rate among the elderly, and the detailed protocols outlined in this new book in the Methods in Molecular Biology series will extend our understanding of the bacterium and aid its elimination from our water supplies.

Drawn from ASM′s 1992 symposium on the subject, this book completely updates information on all aspects of Legionella and Legionnaires disease. Strategy sessions held at the symposium to address current issues involving preventive measures to minimize the presence of Legionella and occurence of Legionnaires disease, the evolution of chemotherapy and diagnostic tests, and prospects for vaccine development are summarized. Legionella is required reading for anyone working in this area of infectious disease. As the sole source of current knowledge and theory on Legionella, it is an extremely useful reference for clinical microbiologists, environmental microbiologists, epidemiologists, infectious disease and other clinical specialists, and environmental engineers.

Environmental mycobacteria can be found in diverse environments around the world, some of which have the ability to infect animals, birds and humans and have evolved mechanisms by which they can invade and grow within host cells, the pathogenic environmental mycobacteria (PEM). Although the diseases caused by these organisms have been known for many years, it is only recently that the potential significance of PEM as a waterborne pathogen has been appreciated. This publication discusses current knowledge about the distribution of PEM in water and other parts of the environment, the routes of transmission that lead to human infection, the most significant disease symptoms that can follow infection, methods of analysis and detection, the control of PEM in drinking-water and the assessment and management of risks.

Protecting and maintaining water distributions systems is crucial to ensuring high quality drinking water. Distribution systems-consisting of pipes, pumps, valves, storage tanks, reservoirs, meters, fittings, and other hydraulic appurtenances-carry drinking water from a centralized treatment plant or well supplies to consumers' taps. Spanning almost 1 million miles in the United States, distribution systems represent the vast majority of physical infrastructure for water supplies, and thus constitute the primary management challenge from both an operational and public health standpoint. Recent data on waterborne disease outbreaks suggest that distribution systems remain a source of contamination that has yet to be fully addressed. This report evaluates approaches for risk characterization and recent data, and it identifies a variety of strategies that could be considered to reduce the risks posed by water-quality deteriorating events in distribution systems. Particular attention is given to backflow events via cross connections, the potential for contamination of the distribution system during construction and repair activities, maintenance of storage facilities, and the role of premise plumbing in public health risk. The report also identifies advances in detection, monitoring and modeling, analytical methods, and research and development opportunities that will enable the water supply industry to further reduce risks associated with drinking water distribution systems.