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Diseases caused by pathogenic microorganisms transmitted by waters

Waterborne diseases are conditions (meaning adverse effects on human health, such as death, disability, illness or disorders) caused by pathogenic micro organisms that are transmitted by water. These diseases can be spread while bathing, washing, drinking water, or by eating food exposed to contaminated water. They are a pressing issue in rural areas amongst developing countries all over the world. While diarrhea and vomiting are the most commonly reported symptoms of waterborne illness, other symptoms can include skin, ear, respiratory, or eye problems. Lack of clean water supply, sanitation and hygiene (WASH) are major causes for the spread of waterborne diseases in a community. Therefore, reliable access to clean drinking water and sanitation is the main method to prevent waterborne diseases. Another class of waterborne metazoan pathogens are certain members of the Schistosomatidae, a family of blood flukes. They usually infect people that make skin contact with the water.

The term waterborne disease is reserved largely for infections that predominantly are transmitted through contact with or consumption of microbially polluted water. Many infections may be transmitted by microbes or parasites that accidentally, possibly as a result of exceptional circumstances, have entered the water. However, the fact that there might be an occasional infection need not mean that it is useful to categorize the resulting disease as "waterborne". Nor is it common practice to refer to diseases such as malaria as "waterborne" just because mosquitoes have aquatic phases in their life cycles, or because treating the water they inhabit happens to be an effective strategy in control of the mosquitoes that are the vectors. A related term is "water related disease" which is defined as "any significant or widespread adverse effects on human health, such as death, disability, illness or disorders, caused directly or indirectly by the condition, or changes in the quantity or quality of any water". Less developed countries might be more at risk for potential outbreaks of waterborne diseases but more developed regions also are at risk to waterborne disease outbreaks.

Disease and transmission Microbial agent Sources of agent in water supply General symptomsAcanthamoeba keratitis (cleaning of contact lenses with contaminated water)Acanthamoeba spp. (A. castellanii and A. polyphaga)widely distributed free living amoebae found in many types of aquatic environments, including surface water, tap water, swimming pools, and contact lens solutionsEye pain, eye redness, blurred vision, sensitivity to light, sensation of something in the eye, and excessive tearing Amoebiasis (hand to mouth) Protozoan (Entamoeba histolytica) (Cyst like appearance) Sewage, non treated drinking water, flies in water supply, saliva transfer(if the other person has the disease) Abdominal discomfort, fatigue, weight loss, diarrhea, bloating, fever Cryptosporidiosis (oral) Protozoan (Cryptosporidium parvum) Collects on water filters and membranes that cannot be disinfected, animal manure, seasonal runoff of water. Flu like symptoms, watery diarrhea, loss of appetite, substantial loss of weight, bloating, increased gas, nausea Cyclosporiasis Protozoan parasite (Cyclospora cayetanensis) Sewage, non treated drinking water cramps, nausea, vomiting, muscle aches, fever, and fatigue Giardiasis (fecal oral) (hand to mouth) Protozoan (Giardia lamblia) Most common intestinal parasite Untreated water, poor disinfection, pipe breaks, leaks, groundwater contamination, campgrounds where humans and wildlife use same source of water. Beavers and muskrats create ponds that act as reservoirs for Giardia. Diarrhea, abdominal discomfort, bloating, and flatulence Microsporidiosis Protozoan phylum (Microsporidia), but closely related to fungi Encephalitozoon intestinalis has been detected in groundwater, the origin of drinking water Diarrhea and wasting in immunocompromised individuals. Naegleriasis (primary amebic meningoencephalitis [PAM]) (nasal) Protozoan (Naegleria fowleri) (Cyst like appearance) Watersports, non chlorinated water Headache, vomiting, confusion, loss of balance, light sensitivity, hallucinations, fatigue, weight loss, fever, and coma

Disease and transmission Microbial agent Sources of agent in water supply General symptoms Botulism Clostridium botulinum Bacteria can enter an open wound from contaminated water sources. Can enter the gastrointestinal tract through consumption of contaminated drinking water or (more commonly) food Dry mouth, blurred and/or double vision, difficulty swallowing, muscle weakness, difficulty breathing, slurred speech, vomiting and sometimes diarrhea. Death is usually caused by respiratory failure. Campylobacteriosis Most commonly caused by Campylobacter jejuni Drinking water contaminated with feces Produces dysentery like symptoms along with a high fever. Usually lasts 2–10 days. Cholera Spread by the bacterium Vibrio cholerae Drinking water contaminated with the bacterium In severe forms it is known to be one of the most rapidly fatal illnesses known. Symptoms include very watery diarrhea, nausea, cramps, nosebleed, rapid pulse, vomiting, and hypovolemic shock (in severe cases), at which point death can occur in 12–18 hours. E. coli Infection Certain strains of Escherichia coli (commonly E. coli) Water contaminated with the bacteria Mostly diarrhea. Can cause death in immunocompromised individuals, the very young, and the elderly due to dehydration from prolonged illness. M. marinum infection Mycobacterium marinum Naturally occurs in water, most cases from exposure in swimming pools or more frequently aquariums; rare infection since it mostly infects immunocompromised individuals Symptoms include lesions typically located on the elbows, knees, and feet (from swimming pools) or lesions on the hands (aquariums). Lesions may be painless or painful. Dysentery Caused by a number of species in the genera Shigella and Salmonella with the most common being Shigella dysenteriae Water contaminated with the bacterium Frequent passage of feces with blood and/or mucus and in some cases vomiting of blood. Legionellosis (two distinct forms: Legionnaires' disease and Pontiac fever) Caused by bacteria belonging to genus Legionella (90% of cases caused by Legionella pneumophila) Legionella is a very common organism that reproduces to high numbers in warm water; but only causes severe disease when aerosolized. Pontiac fever produces milder symptoms resembling acute influenza without pneumonia. Legionnaires' disease has severe symptoms such as fever, chills, pneumonia (with cough that sometimes produces sputum), ataxia, anorexia, muscle aches, malaise and occasionally diarrhea and vomiting Leptospirosis Caused by bacterium of genus Leptospira Water contaminated by the animal urine carrying the bacteria Begins with flu like symptoms then resolves. The second phase then occurs involving meningitis, liver damage (causes jaundice), and kidney failure Otitis Externa (swimmer's ear) Caused by a number of bacterial and fungal species. Swimming in water contaminated by the responsible pathogens Ear canal swells, causing pain and tenderness to the touch Salmonellosis Caused by many bacteria of genus Salmonella Drinking water contaminated with the bacteria. More common as a food borne illness. Symptoms include diarrhea, fever, vomiting, and abdominal cramps Typhoid fever Salmonella typhi Ingestion of water contaminated with feces of an infected person Characterized by sustained fever up to 40 °C (104 °F), profuse sweating; diarrhea, muscle aches, fatigue, and constipation may occur. Symptoms progress to delirium, and the spleen and liver enlarge if untreated. In this case, it can last up to four weeks and cause death. Some people with typhoid fever develop a rash called "rose spots", small red spots on the abdomen and chest. Vibrio Illness Vibrio vulnificus, Vibrio alginolyticus, and Vibrio parahaemolyticus Can enter wounds from contaminated water. Also acquired by drinking contaminated water or eating undercooked oysters. Symptoms include abdominal tenderness, agitation, bloody stools, chills, confusion, difficulty paying attention (attention deficit), delirium, fluctuating mood, hallucination, nosebleeds, severe fatigue, slow, sluggish, lethargic feeling, weakness.

Disease and transmission Viral agent Sources of agent in water supply General symptoms Hepatitis A Hepatitis A virus (HAV) Can manifest itself in water (and food) Symptoms are only acute (no chronic stage to the virus) and include Fatigue, fever, malaise, abdominal pain, nausea, diarrhea, weight loss, itching, jaundice, and depression. Hepatitis E (fecal oral)Hepatitis E virus (HEV)Enters water through the feces of infected individualsSymptoms of acute hepatitis (liver disease), including fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, jaundice, dark urine, clay colored stool, and joint painAcute gastrointestinal illness [AGI] (fecal oral; spread by food, water, person to person, and fomites)NorovirusEnters water through the feces of infected individualsDiarrhea, vomiting, nausea, stomach pain Poliomyelitis (Polio) Poliovirus Enters water through the feces of infected individuals 90 95% of patients show no symptoms, 4 8% have minor symptoms (comparatively) with delirium, headache, fever, and occasional seizures, and spastic paralysis, 1% have symptoms of non paralytic aseptic meningitis. The rest have serious symptoms resulting in paralysis or death Polyomavirus infection Two of Polyomavirus: JC virus and BK virus Very widespread, can manifest itself in water, ~80% of the population has antibodies to Polyomavirus BK virus produces a mild respiratory infection and can infect the kidneys of immunosuppressed transplant patients. JC virus infects the respiratory system, kidneys or can cause progressive multifocal leukoencephalopathy in the brain (which is fatal).

Disease and transmissionMicrobial agentSources of agent in water supplyGeneral symptomsDesmodesmus infectiondesmodesmus armatusNaturally occurs in water. Can enter open wounds. Similar to fungal infection.

According to the World Health Organization, waterborne diseases account for an estimated 3.6% of the total DALY (disability adjusted life year) global burden of disease, and cause about 1.5 million human deaths annually. The World Health Organization estimates that 58% of that burden, or 842,000 deaths per year, is attributable to a lack of safe drinking water supply, sanitation and hygiene (summarized as WASH). Since 1971, the Centers for Disease Control and Prevention (CDC), the Council of State and Territorial Epidemiologists (CSTE), and the US Environmental Protection Agency (EPA) have maintained this surveillance system for collecting and reporting data on "waterborne disease and outbreaks associated with recreational water, drinking water, environmental, and undetermined exposures to water." "Data from WBDOSS have supported EPA efforts to develop drinking water regulations and have provided guidance for CDC's recreational water activities."

Waterborne diseases were once wrongly explained by the miasma theory, the theory that bad air causes the spread of diseases. However, people started to find a correlation between water quality and waterborne diseases, which led to different water purification methods, such as sand filtering and chlorinating their drinking water. Founders of microscopy, Antonie van Leeuwenhoek and Robert Hooke, used the newly invented microscope to observe for the first time small material particles that were suspended in the water, laying the groundwork for the future understanding of waterborne pathogens and waterborne diseases.