Waterborne diseases

Boiling - This involves bringing the water to its boiling point in a container over heat. The water must be maintained at this temperature 15 to 20 minutes. This will disinfect the water. Boiling water is an effective method of treatment because no important waterborne diseases are caused by heat-resisting organisms. 

Very little is known of the epidemiology of waterborne diseases. The current database is insufficient to determine the scope and intensity of the problem. The devastating effect of epidemics is sufficient to rank water-associated epidemics as a most important public health problem. 

However, very little evidence exists to indicate that current water treatment practices are inadequate (no outbreaks of viral or protozoal infections have been reported and waterborne diseases attributed to these pathogens are rare in this country). 

Curriero FC, Patz JA, Rose JB, Lele S (2001) The association between extreme precipitation and waterborne disease outbreaks in the United States, 1948-1994. Am J Public Health 91 1194-1999... 

Thomas KM, Charron DF, Waltner-Toe ws D et al (2006) A role of high impact weather events in waterborne disease outbreaks in Canada, 1975-2001. IntJ Environ Health Res 16 168-180... 

Auld H, Maclver D, Klaassen J (2004) Heavy rainfall and waterborne disease outbreaks the Walkerton example. J Toxicol Environ Health A 67 1879-1887... 

There are many peer-review publications reporting NoV outbreaks due to food and water. In spite of a recognized publication bias toward these outbreaks, there is a consensus that the scientific literature imder-estimates the contribution of NoV to food and waterborne disease (Efall et al., 2005 Hoffmann et al., 2007 O Brien et al., 2006). Source contamination of food and water is clearly implicated in NoV outbreaks around the world. 

The cholera epidemic that reached Europe and North America in the early 1830s killed more than 20,000 people in England. It was during this epidemic that Queen Victoria s personal physician, Dr. John Snow, removed the handle from the polluted Broad Street pump in London in the first recorded, appropriate measure to prevent waterborne disease. 

The most frequent causes of diseases are toxins produced by bacteria. It is estimated that between three and five billion people suffer from poisonings or toxicoinfections annually and about three million die. Bacteria mainly affect children and in most cases water is the source of infection (bacterial waterborne diseases). Children mostly die due to dehydration and electrolyte imbalance. The majority of children s diarrheas affect infants fed infant formula and so who are not protected by elements of specific immunity transmitted from their mothers. 

The disinfection of drinking water has been rightly hailed as a public health triumph of the twentieth century. Before its widespread use, millions of people died from waterborne diseases. Now, people in developed nations receive quality drinking water every day from their public water systems. However, chemical disinfection has also produced an unintended health hazard the potential for cancer and reproductive and developmental effects (including early-term miscarriages and birth defects) that are associated with chemical disinfection by-products (DBFs) [1-6]. Research is being conducted worldwide to solve these important human health issues. 

Waterborne diseases are relatively rare in nations that have modern water purification systems. During the period 1999-2000, for example, a total of 39 incidents of waterborne disease were associated with drinking water in 25 U.S. states. These incidents affected 2,068 persons, of whom two died. In the 22 cases in which the cause of the outbreak was identified, 20 were due to pathogens and two to chemicals. The most common disease noted was gastroenteritis. About three-quarters of the incidents were found to he related to the... 

By contrast with that in the United States, the incidence of waterborne diseases in less-developed nations is very large, responsible for the deaths of millions of people annually. For example, the World Health Organization estimates that about 4 billion people worldwide are currently infected with some form of dysentery. Of this number, 3 million to 4 million will die each year. The difference in the threat posed by waterborne diseases in developed and less-developed nations results almost entirely from the accessibility of pure, clean water in developed nations. 

Bacteria in water are usually thought of in terms of human disease. Indeed, until quite late in the nineteenth century, disastrous outbreaks of waterborne diseases such as cholera, dysentery, and typhoid fever were common in the major cities of the world. The last outbreak of typhoid in the United Kingdom occurred in Croydon in 1937. Serious cholera epidemics still occur in some parts of the world one that began in Peru in 1991 spread to several countries in the Americas, causing 391,000 cases of illness and 4000 deaths that year. 

This situation provided the opportunity for the decision maker to consider many other factors when the control decision was made. The predominant factors driving the control decision were judgmental and unquantifiable. They included the essentiality of the disinfection process in the control of waterborne disease (which is a large risk), the desire to optimize drinking water quality so as to avoid unnecessary risks, and the consideration of the unique compliance problems of small underfinanced and marginally operated water systems. Ultimately, the decision was driven by the feasibility and costs of treatment process improvements. 

An adequate supply of clean, potable WATER is one of the primary requirements for good health. Traditionally, health hazards associated with water have been the classic waterborne diseases, namely, typhoid, cholera, and hepatitis. The advent, advancement, and practice of the science of bacteriology after the late 18th century led to the recognition of the causes and sources of these diseases, which resulted in the development of disinfection processes and in the recognition of the necessity to prevent public potable water sources from pollution from sewage and postdisinfection contamination. 

Another common source of groundwater pollution is sewage, which includes drainage from septic tanks and inadequate or broken sewer lines. Animal sewage, especially from factory-style animal farms, is also a source of groundwater (and river water) pollution. Sewage water contains bacteria, which if untreated can cause waterborne diseases such as typhoid, cholera, and infectious hepatitis. If the contaminated groundwater travels relatively quickly... 

An adequate supply of water is essential to the health and well-being of the world s population. Across the planet, biological and chemical pollutants are affecting the quality of our water. An adequate supply of fresh drinking water is needed for everyone on the planet. Lack of availability of fresh water leads to waterborne diseases, such as cholera and typhoid, and to diarrhoea, which is one of the biggest killers across the world. 

Microbial hazards make the largest contribution to waterborne disease in developed and developing countries, Nevertheless, chemicals in water supplies can cause serious health problems - whether the chemicals are naturally occurring or derive from sources of pollution. At a global scale, fluoride and arsenic are the most significant chemicals, each affecting perhaps millions of people, However, many other chemicals can be important contaminants of drinking-water under specific local conditions. 

Identify the primary pathogens responsible for foodborne and waterborne disease. 

Water quality. Water at the point of collection is palatable and potable and can be used for personal and domestic hygiene without causing significant risk to health because of waterborne diseases or chemical or radiological contamination from short-term use. 

Potential waterborne diseases that follow tsunamis include cholera diarrheal or fecal-oral diseases, such as amebiasis, cryptosporidiosis, cyclosporiasis, giardiasis, hepatitis A and E, leptospirosis, parasitic infections, rotavirus, shigellosis, and typhoid fever animal- or mosquito-borne illness, such as plague, rabies, malaria, Japanese encephalitis, and dengue fever (and the potentially fatal complication dengue hemorrhagic shock syndrome) and wound-associated infections and diseases, such as tetanus. Mental health concerns are another consequence of tsunami events. 

Kime, J. A., Lowe, E. P. (1971). Human oral dose for ten selected food- and waterborne diseases. Frederick, MD Department of the Army. 

The continued construction of hydroelectric dams and expansion of agricultural and urban areas adds urgency to increasing our ability to forecast biogeochemical consequences of such developments in the Amazon basin. Applications of limnological understanding to timber management in flooded forests, to fisheries, to conservation of aquatic biodiversity, to control of waterborne disease vectors and to amelioration of... 

However, to effectively control the waterborne diseases, a combination of various chemical and physical processes is often adopted in typical water and wastewater disinfection processes. 

Drinking water has been disinfected with chlorine for approximately 100 years to protect against waterborne infectious diseases. In addition to chlorination, other methods of drinking water disinfection include the use of chlorine dioxide (either alone or in combination with chlorine), the addition of ammonia to chlorine to form chloramines, ozone treatment, oxidation with potassium permanganate, and ultraviolet radiation. Chlorination, however, is by far the most widely used method. Treatment with chlorine has virtually eliminated cholera, typhoid, dysentery, hepatitis A, and other waterborne diseases)54 ... 

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