Acanthamoeba spp.

Free-living ameboid protozoa found usually in fresh water or moist soil.

Acceptable risk

Level of risk such that the benefits derived by an organism, a population or an ecological system are perceived to outweigh the adverse effects that might affect them as a result of being administers or exposed to a particular agent.


It is the ability to measure the target chemical in an unbiased manner and is usually defined with regards to a positive success rate. Accuracy together with sensitivity are two parameters are typically quantified in terms of false positives and false negatives, best addressed through challenge samples.


A heterogeneous collection of bacteria that form branching filaments.

Activated sludge

As process: A continuous biological treatment process done mainly by bacteria which oxidize carbonaceous and nitrogenous matter in wastewater. 

As subject: a biological active floc composed mainly of bacteria and protozoa used on wastewater treatment process for oxidazing carbonaceous pollution in water by providing air or oxygen and later allowing the settlement of biological flocs (the sludge blanket) to clarify the treated water.

Acute gastroenteritis

Inflammation of gastric and intestinal mucosa caused by bacteria or viruses. It could be accompanied by fever and abdominal pain, resulting in vomiting, diarrhea and other dyspeptic symptoms. It is usually associated with spoiled food and beverages.

Acute hemorrhagic conjunctivitis

A conjunctival congestion, vascular dilatation, and onset of edema due to a highly contagious infection with enteroviruses.

Adenoviral keratoconjunctivitis

Inflammation of the cornea and the conjunctiva caused by Adenovirus.


Adhesion of some elements (atoms, ions, molecules, virus, cells, ….) from differential phase (gas, liquid, or dissolved solid) to a surface. This process creates a film of the adsorbated element on the surface of the adsorbent.


Bulk transport of the mass of discrete chemical or biological constituents by fluid flow within a receiving water. Advection describes the mass transport due to the velocity, or flow, of the waterbody.

Adverse effect

An undesired harmful effect resulting from an action or other intervention in a system (environment, livin being, ecosystem, etc).


Acute flaccid paralysis


A small, highly basic protein with a critical role in the regulation of viral gene expression and replication, and in the modulation of certain important host cell functions including cell cycle progression and DNA repair.


Metabolism of living being that do not need oxygen and get energy from oxidation reactions in which the final electron acceptor is organic matter.

Anaerobic digestion

The use of anaerobic bacteria in a biodegrable process to breakdown waste, with biogas as a valuable byproduct

Anaerobic thermophilic

Collection of processes by which anaerobic microorganisms break down biodegradable material in the absence of oxygen in elevated temperatures in the range 45 to 70 °C, where thermophiles are the primary microorganisms present.

Anoxic digestion

A process by which microorganisms break down biodegradable material in the absence of oxygen.

Antibiotic resistance

Antibiotic resistance refers specifically to the resistance to antibiotics that occurs in common bacteria that cause infections. The evolution of resistant strains is a natural phenomenon that occurs when microorganisms replicate themselves erroneously or when resistant traits are exchanged between them. The use and misuse of antimicrobial drugs accelerates the emergence of drug-resistant strains. Poor infection control practices, inadequate sanitary conditions and inappropriate food-handling encourage the further spread of antimicrobial resistance.

Antibiotic Resistance Analysis

Method that analysis the specific traits of resistance against antibiotics of a bacterial strain in order to generate antibiotic resistance profiles for choosing the right antibiotics for medication or for bacterial typing or source tracking.


The state or property of eliciting an immune reaction to an antibody.

Antimicrobial resistance

More general term than antibiotic resistance that also includes the ability of viruses and parasites, as well as bacteria, to survive treatments with drugs or chemicals.


An underground geological formation or group of formations, containing or conducting water. Aquifers are sources of groundwater for wells and springs.

Aseptic meningitis

A condition in which the layers lining the brain, the meninges, become inflamed due to a non-bacterial cause.


Neither causing nor exhibiting symptoms of disease.


Vaccine derived polioviruses excreted by an anonymous individual



Microscopically small living organisms usually consisting of a single cell (a few micrometers in length). Among the first live forms on earth. Bacteria are breaking down organic matter and are essential mediators to keep the nutrient cycles running. They can also aid in pollution control. Some bacteria may also cause human, animal and plant health problems (bacterial pathogens).


Bacteriophages are bacterial viruses. They are very ubiquitous in the environment. They are also used for water quality testing as they are considered to show a similar fate and persistence in the environment as compared to human enteric viruses. Frequently used phages are somatic coliphages, male-specific RNA coliphages (F-RNA coliphages) and phages infecting Bacteroides fragilis.


The order Bacteroidales is composed of obligately anaerobic bacteria, Gram-negative rods that are abundant in the intestines of warm-blooded animals and humans.

Bacteroides fragilis bacteriophages

These phages infecting Bacteroides fragilis, a very abundant anaerobic bacteria in the gut, belong to the family Siphoviridae with flexible tail (dsDNA, long non-contractile tails, capsids up to 60 nm). Phages infecting the host strain, B. fragilis HSP40 are considered to be human-associated, but phages infecting B. fragilis RYC2056 are more numerous and not human-associated.


The phylum Bacteroidetes is composed of three large classes of Gram negative, non-spore forming anaerobic or aerobic rod-shaped bacteria. Bacteria that are widely distributes in the environment, including soil, sediments and sea water, as we as in the guts and the skin of animals and humans.

Basepairs (Bp)

A base pair (bp) is a unit consisting of two bases bound to each other by hydrogen bonds. Base pairs form the building blocks of the DNA double helix.


Obligately anaerobic, non-acid-fast, non-spore-forming, non-motile, Gram-positive bacteria which are highly pleomorphic and may exhibit branching bulbs (bifids), clubs, coccoid, coryneform, Y and V forms. They are all catalase-negative and ferment lactose (except the three insect species; B. asteroides, B. indicum and B. coryneforme). Bifidobacteria are a very numerous group of bacteria in the faeces of warmblooded animals and humans.

Biliary secretions

Secretion of dark green to yellowish brown fluid, produced by the liver of most vertebrates, that aids the digestion of lipids in the small intestine.


The use of computer science, mathematics, and information theory to organize complex biological data, especially to compare and analyze sequence data from DNA, RNA or proteins.


A kind of 'biological monitoring instrument', a selected organism (or a group of organism) that gives a warning or indicates danger.


Abbreviation for human BK polyomavirus.


Biological Oxygen Demand where BODn is the BOD removed within “n” days


Capsid proteins

Proteins of the virus shell  that encloses the nucleic acid of the vírus


Morphological subunit of the capsid of a virus

Carbon source utilization profile

This method are based on the hability of bacteria to metabolize numerous carbon and nitrogen substrates


Conventional activated sludge reactor


A type I transmembrane protein present on thymocytes, T cells, B cells, natural killer cells, monocytes, neutrophils, platelets, endothelial cells, epithelial cells, fibroblasts, placenta, and sperm that protects against complement-mediated damage.


Center for Disease Control and Prevention (Atlanta, GA, USA)

Chelating agents

Organic compounds capable of forming coordinate bonds with metals through two or more atoms of the organic compound


An antiviral nucleoside analogue used in treatment of cytomegalovirus retinitis in patients with acquired immunodeficiency syndrome; administered by intravenous infusion.


An isolate or group of isolates descending from a common precursor strain by nonsexual reproduction exhibiting phenotypic and/or genotypic traits characterised by a strain-typing method to belong to the same group.

Clostridium perfringens

A bacterial species belongs to the sulphite-reducing clostridia. In addition they also ferment lactose, sucrose and inositol with the production of gas, produce a stormy clot fermentation with milk, reduce nitrate, hydrolyse gelatin and produce lecithinase and acid phosphatase.


Central nervous system


Substances that cause coagulation when introduced into a fluid medium containing tiny particles.


A coliphage is a bacteriophage that infects Escherichia coli. Somatic coliphages attack E. coli strains via the cell wall and include spherical phages of the family Microviridae and various tailed phages in 3 families. The F-RNA coliphages attack E. coli strains via the sex pili (F factor) and are single-stranded RNA non-tailed phages in four groups.




An illness, with in- flammation of the nasal passages, in which someone sneezes and coughs and has a blocked and running nose.


Means “widely distributed” 


A group of picornaviruses, included in the genus Enterovirus, of icosahedral shape, stable at acid pH, and about 28 nm in diameter, causing myositis, paralysis, and death in young mice, and responsible for a variety of diseases in humans, although unapparent infections are common.


It is a single-celled protozoan parasite commonly found in lakes and rivers, especially when the water is contaminated with sewage and animal waste. Cryptosporidium can cause gastrointestinal illness (e.g., diarrhoea, vomiting, cramps).

Culture‐dependent methods

Methods relying on the cultivation of bacteria or viruses in the lab.

Culture‐independent methods

Methods detecting indicators or markers without the necessity of microbiological or cell-culture based cultivation. For example DNA- or RNA-based methods or immunological methods.


Coxsackievirus (Note: a letter and number after “CV” refers to the genotype of CV, e.g. CVA6 is Coxsackie virus type A6; while the letter “A” or “B” without a number, refers to all Coxsackie viruses of that Type)


A group of viruses in the family Herpesviridae infecting humans and other animals, many of these viruses having special affinity for salivary glands, and causing enlargement of cells of various organs and development of characteristic inclusions (owl eye) in the cytoplasm or nucleus. Infection of embryo in utero may result in malformation and fetal death.

Cytopathic effect

Damage to host cells during virus invasion. Cytopathic effect is abbreviated CPE.

Cytosine arabinoside

A chemotherapy agent used mainly in the treatment of cancers of white blood cells.  It is also known as cytarabine; it is called cytosine arabinoside because it combines a cytosine base with an arabinose sugar.



Disability-adjusted life year (DALY) losses

The various hazards that can be present in water, excreta, wastewaters and polluted surface waters can have very different health outcomes. Some outcomes are mild (e.g., diarrhea,), while others can be severe (cholera, haemolytic uraemic syndrome associated with E. coli O157, or cancer); some are acute (diarrhea), while others are delayed (infectious hepatitis, cancer); some especially relate to certain age ranges and groups (skeletal fluorosis in older adults often arises from long-term exposure to high levels of fluoride in childhood; infection with hepatitis E virus has a very high mortality rate among pregnant women). In addition, any one hazard may cause multiple effects (e.g., gastroenteritis, Guillain-Barré syndrome, reactive arthritis and mortality associated with Campylobacter).

In order to support public health priority setting a common metric is required that can be applied to all types of hazard and takes into account different health outcomes including probabilities, severities and durations of effects. Disability-adjusted Life Years (DALYs) provides this metric. The basic principle of the DALY is to weight each health impact in terms of severity within the range of 0 for good health to 1 for death. The weighting is then multiplied by duration of the effect and the number of people affected. In the case of death duration is regarded as the years lost in relation to normal life expectancy (taken as 70 years). Using this approach a mild diarrhea with a severity weighting of 0.1 and lasting for 7 days results in a DALY loss of [(0.1 × 7)/365] – i.e., 0.002; while death resulting in a loss of 30 years of life equates to a DALY loss of 30. [Strictly speaking DALY losses have units of years, but generally they are just expressed as a number.]

Hence, DALYs = YLL (years of life lost) + YLD (years lived with a disability or illness) − in this context ‘disability’ refers to conditions that detract from good health.

Calculation of DALY losses

Infection with rotavirus (in developed countries), for example, causes:

     ● mild diarrhea (severity rating of 0.1) lasting 7 days in 97.5% of cases

     ● severe diarrhea (severity rating of 0.23) lasting 7 days in 2.5% of cases

     ● the death (severity rating of 1) of very young children in 0.015% of cases



Disinfection byproduct


This is the irreversible destruction of the contaminant by chemical, physical, or biological processes.

Decision making

The process of reviewing the findings and recommendations of a Health Impact Assessment and making choices about how they should be taken forward.


A setting of limits; a boundary.


To destroy or remove the myelin sheath of (a nerve fiber), as through disease.


A cell surface molecule encoded by the DSG2gene, typically found in desmosomes that makes skin cells adhere to each other.


The movement of suspended or dissolved particles from a more concentrated to a less concentrated region as a result of the random movement of individual particles; the process tends to distribute them uniformly throughout the available volume.

Direct conjunctival inoculation

Direct introduction of the pathogen into the mucous membrane in the anterior surface of the eyeball and the posterior surface of the lids.

Direct immunoperoxidase

Refer to a sub-class of immunohistochemical or immunocytochemical procedures in which the antibodies are visualized via a peroxidase-catalyzed reaction

Disability Adjusted Life Years

One DALY is one lost year of "healthy" life. The sum of these DALYs across the population, or the burden of disease, can be thought of as a measurement of the gap between current health status and an ideal health situation where the entire population lives to an advanced age, free of disease and disability.

Discriminatory power

The ability of a test to generate distinct and discrete units of information from different isolates, usually at a subspecies level.


Irreversible inactivation of pathogens to reach a concentration level at which infection of humans is unlikely.


Echerichia coli

Is a bacterium that is commonly found in the gut of humans and warm-blooded animals. Most strains of E. coli are harmless. Some strains however, such as enterohaemorrhagic E. coli (EHEC), can cause severe foodborne disease.


The interrelationships between organisms and between organisms and their environment; the study of such interrelationships.

Economic instruments

A measure taken by governments, agencies or managers to alter the operation of the market, involving the simulation or suppression of demand or supply or goods and services, often by the manipulation of prices. Note: Taxes, subsidies, prices for licences and incentive payments are common examples.


Effluent is an outflowing of water from a natural body. In the context of waste water treatment plants, effluent that has been treated is sometimes called secondary or tertiary effluent, or treated effluent.

Electrodialytic process

Electrodialysis treatment process is one of the water treatment methods and uses membranes semipermeable to ions based on their charge, employing electrical current to reduce the ionic content of water. 

Electrostatic binding

It is the binding between molecules based on electrostatic forces, the forces between particles that are caused by their electric charges. One way proteins recognize each other is via electrostatic interactions, or interactions among charged and polar parts of proteins.


Process by which a virus' nucleic acid is enclosed in a capsid.


An inflammation of the brain, usually caused by a direct viral infection or a hyper-sensitivity reaction to avirus or foreign protein.


Produced within or caused by factors within the organism.

Endogenous adenovirus infection

Endogenous substances and processes are those that originate from within an organism, tissue, or cell. Adenoviruses are not inserted into the genomes of cells, however they can persist in a latent form in cells and be reactivated under certain circumstances causing disease.


"Legal action taken by component government, national or local authorities or their executive or legal branches to obtain compliance with, or to ensure operation or observance of, laws, rules, regulations, orders, contracts or agreements and/or to obtain penalties or criminal sanctions for violations. Note: Enforcement procedures may vary depending of the requirements of different laws and regulations having an impact on environment and health"


Of intestinal origen, especially applied to waste, bacteria or viruses.


All faecal streptococci that grow at pH 9.6, 10° and 45°C and in 6.5% NaCl. Nearly all are members of the genus Enterococcus, and also fulfill the following criteria: resistance to 60°C for 30 min and ability to reduce 0.1% methylene blue. The enterococci are a subset of Faecal Streptococci that grow under the conditions outlined above. Alternatively, enterococci can be directly identified as microorganisms capable of aerobic growth at 44±0.5°C and of hydrolysing 4-methlumbelliferyl-β-D-glucoside (MUD, detecting β-glucosidase activity by blue florescence at 366nm), in the presence of thallium acetate, nalidixic acid and 2,3,5-triphenyltetrazolium chloride (TTC, which is reduced to the red formazan) in the specified medium.


Related to the Enterovirus, a genus of the picornaviruses including polioviruses, coxsackieviruses, echoviruses and other enteroviruses.


They are small viruses in the genus Enterovirus that can multiply in the intestines of infected humans or animals producing subclinical and less frequently a wide diversity of types of infections. This group includes the polioviruses, coxsackieviruses, echoviruses, and other enteroviruses. 

Environmental and health

A conceptual domain covering the interrelationship between human health and the environment, linking improvement of human health, now an in future generations, to the protection, restoration and improvement of environmental quality.

Environmental assessment/environmental impact assessment

The process of evaluating the possible environmental consequences of a past, current or proposed action, development project or piece of legislation, as an aid to decision-making, that may result in the production of an environmental impact statement. It also attempts to evaluate the measures to be taken to minimize an adverse effect. Note: Environmental impact assessment is generally used to describe a formal process dealing with specific proposed actions. In some cases an environmental assessment will also include evaluation of the consequences for human health.


Environmental surveillance


Regarding the branch of medicine that deals with the study of the causes, distribution, and control of disease in populations.

Ethylenediaminetetraacetic Acid

An aminopolycarboxylic acid and a colourless, water-soluble solid and decomposing above 160°C


A genus of large rigid ovoid hypotrichous ciliates extremely common in fresh and salt water.

Euplotes octocarinatus

Species of freshwater protozoan ciliates known to express defensive morphologies and behaviour in response to their predators.


Enterovirus, (Note: a hyphen “_” and a number or number and letter after “EV” revers to the EV serotype or genotype, e.g. EV-71 is Enterovirus genotype 71


The removal of the waste products of cell metabolism and in humans or animals removal of feces, urine, and other wastes from the body via the colon, kidneys, lungs, or skin 


Organism capable of functioning under varying environmental conditions. Used of certain organisms, such as bacteria that can live with or without oxygen. A facultative parasite can exist as a parasite or a saprotroph. In the facultative ponds in wastewater treatment plants there is a process in which most of the remaining BOD is removed through the coordinated activity of algae and heterotrophic bacteria.
Faeacal Indicator (microbial)

Used to sensitively indicate microbial faecal pollution from humans and/or animals in water. Information on the specific nature of the applied faecal indicator, such as sensitivity, specificity, persistence, or resistance, has to be given in order to appropriately characterise the expected indicator capacity. It is important to distinguish between indicators for total faecal pollution, including human and animals, from host-associated faecal indicators (also known as source tracking indicators or markers).

Faecal coliforms

Bacteria which ferment lactose and produce gas in lauryl sulphate broth within a period of 48 +/- 2 h when incubated at 37 +/- 0,2 °C, and in addition produce indol in tryptone broth within 24 +/2 2 h when incubated at 44 +/- 0,2 °C

Faecal Indicator

"A group of organisms that indicates the presence of faecal contamination, such as the bacterial groups thermotolerant coliforms or E. coli. Hence, they only infer that pathogens may be present."

Faecal source

Refers to a host that shed the faeces which is causing faecal pollution in water. Depending on the specificity of an MST method, a faecal source might refer to a general group of host (e.g., all humans, all animals, or a group of animals such as canines, birds, rodents, or ruminant animals), a type of faecal waste (municipal sewage, agricultural sewage, residential septage, or an individual faeces), or a specific host animal species (e.g. human, cattle, dogs, ducks,etc.). Sometimes ambigously used for of point source of pollution (e.g. Sewage effluent pipe).

Faecal streptococci

Gram-positive, catalase-negative cocci from selective media (e.g. azide dextrose broth or m-Enterococcus agar) that grow on bile esculin agar and at 45°C, belonging to the genera Enterococcus and Streptococcus possessing the Lancefield group D antigen.


A source or target is not identified when it is actually present.


A source or target is detected when it is not actually present.


Pattern of distribution of an agent, its derivatives, or metabolites in an organism, system, compartment, or (sub) population of concern as a result of transport, partitioning, transformation, or degradation


Pertaining to or characterized by an elevated body temperature, above 100° F (37.8° C), or 99.6° F (37.6° C) rectally, is commonly regarded as febrile.

Fecal Coliform Bacteria

"Gram-negative, non spore-forming, oxidase-negative, rod-shaped facultative anaerobic bacteria that ferment lactose (with β-galactosidase) to acid and gas within 24–48h at 36±2°C. Not specific indicators of faecal pollution"



A nucleoside analogue that acts as a broad-spectrum antiviral.


Inflammation of the mucous membrane of the stomach and intestines.

Gender mainstreaming

Gender mainstreaming is the public policy concept of assessing the different implications for women and men of any planned policy action, including legislation and programmes, in all areas and levels.

In the world of work it is a means of integrating equality concerns across the board into all policy objectives and all activities in order to promote equality of all workers, irrespective of sex.


Pertaining to the urinary system and genitalia.


The analysis is based directly on the DNA of the organisms. Ribotyping and PCR are both genotypic analyses.


Methods distinguish among bacterial or viral strains (or subspecies) based directly on their unique genetic makeup and are often referred to as “DNA fingerprinting.”


Pertaining to elderly persons or to the aging process.

Giardia lamblia

Flagellate protozoan which is shed during its cyst state into the faeces of man and animals. When water containing these cysts is ingested, the protozoan causes a severe gastrointestinal disease called giardiasis.


Proteins with covalently attached sugar units, either bonded via the OH group of serine or threonine O glycosylated) or through the amide NH2 of asparagine (N glycosylated).


World Health Authority Global Polio Eradication Initiative


"Descriptions of the steps that should be taken in performing a task or implementing a policy and the manner of doing so, including application of recommended values. Note: Guidelines are frequently built up from reviews of practice. They are more specific and more detail than guiding principles, on which they are based. They are not prescriptive or enforceable (in the way a standard may be) but are issued to assist managers in devising local means of implementing policy. Guidelines may incorporate recommendations for numerical values for pollutants of concern, such as WHO’s guidelines on drinking water quality."



A biological, chemical, physical or radiological agent that has the potential to cause harm Health Based Targets. A defined level of health protection for a given exposure. This can be based on health outcome targets, water quality targets, performance targets, specified technology targets.

Health Based Targets

A defined level of health protection for a given exposure. This can be based on health outcome targets, water quality targets, performance targets, specified technology targets.


A vermiform parasite, primarily, nematodes (roundworms), cestodes, (tapeworms) and trematodes (flukes).


The agglutination of red blood cells.

Hematopoietic cell transplantation

Removal of blood-forming cells from one person and their infusion into another.

Heparan sulfate

A glycosaminoglycan occurring in the cell membrane of most cells, consisting of a repeating disaccharide unit of glucosamine and uronic acid residues, which may be acetylated and sulfated; it accumulates in several mucopolysaccharidoses.


The hepatitis A viruses, a genus of Picornaviruses.

Heterotrophic plate count

A method that measures colony formation on culture media widely used to measure the heterotrophic microorganism population in drinking-water and other media.


Major coat protein found in Adenoviruses.


Hand-foot-mouth disease


Proteins having identical or similar functions (particularly with respect to proteins from different species).


Microorganism predominantly occuring in a specific host animal. Potentially co-evolved with host and interacting with its preferred host on a genetic or immunological level.


Microorganisms that have an exclusive or prefential asocciation with the gastrointestinal tract of a particular host species or group


Human Parechovirus


Human polyomavirus 10.


Human polyomavirus 12.


Human polyomavirus 6


Human polyomavirus 7.


Human Rhinovirus

Human exposure evaluation

A component of risk assessment that involves describing the nature and size of the population exposed to a substance and the magnitude and duration of their exposure. The evaluation could concern past exposures, current exposures, or anticipated exposures.


Inability of dissolving in water.



Integrated cell culture and PCR


Presenting 20 equilateral triangular surfaces and 12 vertices, as do most viruses with cubic symmetry.

Icosahedral capsid

Capsid presenting 20 equilateral triangular surfaces and 12 vertices, as do most viruses with cubic symmetry.

Icosahedric capsid

Capsid presenting 20 equilateral triangular surfaces and 12 vertices, as do most viruses with cubic symmetry.


A polyhedron with 20 faces.


Incapable of developing a normal immune response, usually as a result of disease, malnutrition, or immunosuppressive therapy.


A group of disorders in which part of the immune system is missing or defective.Therefore, the body's ability to fight infections is impaired.


Antibodies, protective proteins produced by cloned B lymphocyte-derived plasma cells.


Regarding the branch of biomedicine concerned with the structure and function of the immune system, innate and acquired immunity, the bodily distinction of self from nonself, and laboratory techniques involving the interaction of antigens with specific antibodies.


Capable of modifying or regulating one or more immune functions.

Index indicator

It is one that points to the presence of pathogenic organisms. The term 'index organisms' has been introduced for markers whose presence in numbers exceeding given numerical limits indicates the possible occurrence of ecologically similar pathogens.

Index Pathogen

Selected pathogen for quantitative microbial risk assessment (QMRA).


Indicator organisms are used for a wide range of purposes, including as indicators of: i) the effectiveness of processes such as filtration or disinfection, ii) integrity and cleanliness of distribution systems, iii) or faecal pollution analysis.

Indirect immunofluorescence

Technique used for light microscopy with a fluorescence microscope and is used primarily on microbiological samples. Secondary, or indirect, immunofluorescence uses two antibodies; the unlabeled first (primary) antibody specifically binds the target molecule, and the secondary antibody, which carries the fluorophore, recognises the primary antibody and binds to it.


The entry and development or multiplication of an infectious a biological agent (including virus, bacterium, protist, and helminth) in a host. Infection may or may not lead to disease symptoms (e.g. diarrhoea). Infection can be measured by detecting infectious agents in excreta of colonized areas or through measurement of a host immune response (i.e. the presence of antibodies against the infectious agant agent).


Parasitic attack or subsistence on the skin and/or its appendages, as by insects, mites, or ticks; sometimes used to denote parasitic invasion of the organs and tissues, as by helminths.


Pertaining to the littoral region that is above the low-water mark and below the high-water mark.


Invagination of a tubular organ or part, esp the telescoping of one section of the intestinal tract into a lower section, causing obstruction.

Isoelectric points

 pH values of the dispersion medium of a colloidal suspension at which the colloidal particles do not move in anelectric field.


A population of microbial cells in pure culture derived from a single colony on an isolation plate and identified to the species level.



Human JC polyomavirus.



Inflammation of the cornea and the conjunctiva.



In Microbial Source Tracking is normally refereed to the group of fingerprints generated from microbial isolates collected from the potential sources (i.e., animal faeces) impacting a watershed. Microbial Source Tracking libraries should not be confused with gene cloning libraries. Fingerprints are based on phenotypic traits (e.g., antibiotic resistance analysis) or genotypic profiles (e.g., rep-PCR, ribotyping) of individual microbial strains.

Library‐dependent methods

Identify faecal sources from water samples based on databases of genotypic or phenotypic fingerprints for bacteria strains of known faecal sources. These libraries are often geographically specific.

Library‐independent methods

Identify sources of faecal pollution based on known host‐specific characteristics of an indicator (e.g. bacteria, virus, chemical compound) without the need of a library.

Limit of detection

Lowest amount of analyte in a sample that can be detected with probability, although perhaps no quantified as an exact value

Limit of quantification

Lowest amount of analyte in a sample that can be quantitatively determined with state acceptable, precision and trueness, under state experimental conditions

Log reduction

Log10 Reductions

A mathematical term referring to a 10-fold (or 90%) reduction in the quantitative value of a microbial population.

For example, a 1-log10 reduction means the quantitative value of a microbial population is reduced by 10 times or by 90%. A 2-log10 reduced means the quantitative value of a microbial population is reduced by 100 times or 99%.

Often 4 to 6 log10 reductions are suggested for microbes via treatment thus a pathogen found at 1million per liter in sewage would be reduced to 100 and 1/Liter with 4 to 6 log10 reductions.




Mesophilic anaerobic digestion

Manure worm

An earthworm (Eisenia foetida) that lives near the surface of the soil and is commonly used for composting (vermicomposting) and for bait.


Managed aquifer recharge


Final stages of treatment process, particularly for composting, in which removal of pathogen and nutrient removal (especially nitrogen) is completed.


Membrane bioreactor


Merkel cell polyomavirus.

Mechanical mixing

Commonly applied in biological reactors used for treatment of wastewater or sludge.


 A serious inflammation of the meninges, the thin, membranous covering of the brain and the spinal cord.

Mesophilic anaerobic digester

A biological reactor commonly used for sludge treatment at wastewater treatment plants that breaks down solid matter through hydrolysis, fermentation, and methanogenesis; operating in the absence of oxygen; and typically at 37°C.


The study of the broad range of genetic material (DNA, RNA, nucleotide sequences) that is present in particular environments or natural samples, representing a mixture of the microbes present and the collective summation of their genes.  Metagenomics is a new field that has been enabled by next-generation DNA sequencing technology, which circumvents polymerase chain reaction.

Microbial Monitoring

Microbial monitoring can be undertaken for a range of purposes including validation, operational monitoring, verification, surveillance, etc. The term microbial monitoring is very broad and needs further detailed information to define the intended application.

Microbial Source Tracking

Procedures that use host-specific and host-associated microbial indicators to establish the origin of faecal pollution in water. Other terms that relate to MST are bacterial source tracking (when the bacteria is the target), microbial source identification, and faecal source identification.

Microbial strain

Genetic variant or subtype of a microorganism, such as a viral or bacterial species or subspecies.


A physical filtration process that uses membranes with pore sizes between 0.1 to 10 microns to separate microbial or chemical constituents from water or other liquids based on size. Membrane filtration processes are used most often with low total dissolved solids water such as surface water and fresh groundwater, with the purpose of softening (polyvalent cation removal) and removal of disinfection by-product precursors such as natural organic matter and synthetic organic matter.


An anti-depressant pharmaceutical used to treat Major Depressive Disorder and other mood disorders through enhancing serotonin release and transmission.
Mirtazepine can occur as a trace contaminant in water.


An organelle found in the cells of most eukaryotes that has a crucial role in aerobic production of ATP, the energy currency for the cells. Mitochondria are evolved from bacteria and, as such, contain their own genome, in general circular, which encodes proteins and ribosomal RNAs necessary for mitochondrial function.

Model organism

An organism that behaves in a similar (ideally identical) manner as a pathogen in a given environment or set of conditions; for example, the use of coliphages to model the behaviour of human enteric viruses or the use of non-pathogenic organisms to avoid risk of pathogens in laboratory research.


Periodic, continuous or repeated observation and measurement of data for defined purposes, according to prearranged schedules in space and time, using comparable methods for sensing and data collection.


A term used to refer to either the prevalence or incidence of a disease.


The form and structure of an organism or its components.


The relative incidence of death associated with a disease.


Most probable number of infectious units (Note: “MPNCU” indicates that infectious units are cytopathic units; and MPN can be expressed per weight (MPN/Kg) or volume (MPN/100L)).



A membrane filtration process with pore sizes from 1 - 10 nanometres.  Smaller than microfiltration and ultrafiltration, but larger than reverse osmosis.

Nasopharyngeal aspirates

Body secretion derived from the part of the pharynx above the soft palate that is continuous with the nasal passages.

Neritic zones

The ocean waters from the low tide mark to a depth of about 200 metres.


Refers to the interaction between the central nervous system and endocrine systems for controlling the function of organs and tissues.


The tendency or capacity of a microorganism to cause disease of the nervous system.

Non-enteric Ad carriage

Presence of non-enteric Adenovirus in diarrhoeal stool samples.

Non-point Source Pollution

Pollution that occurs when rainfall, snowmelt, or irrigation runs over land or through the ground, picks up pollutants, and deposits them into rivers, lakes, and coastal water or introduces them into ground water


An infection which is passed on to a person being treated in a hospital.

Nosocomial RVA outbreak

Relating to or being an infection that a patient acquires while being treated in a hospital.

Nosocomial infection

The meaning is a hospital-acquired infection i.e. an infection that is contracted from the environment or staff of a healthcare facility. It can be spread in the hospital environment, nursing home environment, rehabilitation facility, clinic, or other clinical settings.


Norovirus (Note: “NoV” followed by “GGI” or “GGII” refers to norovirus genogroups I and II respectively).


Non-polio enterovirus

Nucleotide sequencing

The process of determining the precise order of nucleotides within a DNA or RNA molecule.


Obligate aerobic treatment process

Process that must, by necessity,  occur in the presence of oxygen.

Operational Monitoring

The act of conducting a planned sequence of observations or measurements of control parameters to assess whether a system is operating within design specifications (e.g. for water treatment, water abstraction). Emphasis is given to monitoring parameters that can be measured quickly, easily and that can indicate if a process is functioning properly. Operational monitoring data should help managers to make corrections that can prevent hazard break-through.


Referring to ophthalmology
, the study of the eye and its diseases.


Oral polio vaccine


Part of or related to the oropharynx, the region of the pharynx that lies underneath the soft palate and posterior to the oral cavity.


Inflammation or infection of the ear.


A sudden increase in the occurrence of a particular disease in a localized group, such as the population of a city.



A tumor suppressor gene frequently measured as a marker of malignant diseases.


An herbaceous annual plant whose leaves can be used for seasoning food.


A genus of viruses in the order Picornavirales.


The quality of producing or the ability to produce pathologic changes or disease.


Peripheral-type benzodiazepine receptor (PBR), a five transmembrane domain mitochondrial protein involved in the regulation of cholesterol transport.


Polymerase chain reaction


Containing antigens from five strains of a microorganism or virus. Used of a vaccine or serum.


Five-sided polygon form.

Peracetic acid

A toxic, colorless liquid with strong aroma; boils at 105°C; explodes at 110°C; miscible with water, alcohol, glycerin, and ether; used as an oxidizer, bleach, catalyst, bactericide, fungicide, epoxy-resin precursor, and chemical intermediate.


Refers to the length of time microbial organism/chemical compound stays in the environment, once introduced. Organism/compound may persist for less than a second or for a long period of time.


Plaque forming unit


The engulfing of microorganisms or other cells and foreign particles by phagocytes.


Inflammation of the mucous membrane and underlying parts of the pharynx.


Characteristics of an organism that rely on translation of genetic information into proteins. Antibiotic resistance patterns and carbon source utilization patterns represent phenotypes, as they are mediated by enzymes and other proteins

Phenotype methods

Distinguish samples based on observable characteristics of the isolated bacteria that might have been acquired from exposure to different host species or environments, such as resistance to certain antibiotic or profiles of carbon utilization. These methods are based on an effect of an organism’s genes that actively produce a biochemical substance. The type and quantity of these substances is what is measured during the laboratory analysis.

Planning and resource allocation

Involves the activities of determining strategic direction, identifying and establishing programs and processes, and allocating resource among those programs and processes.

Point Source Pollution

Identifiable inputs of waste that are discharged via pipes or drains primarily (but no exclusively) from industrial facilities and municipal treatments plants into rivers, lakes, and ocean.


A highly infectious viral disease that chiefly affects children and, in its acute forms, causes inflammation of motorneurons of the spinal cord and brainstem, leading to paralysis, muscular atrophy, and often deformity. Throughvaccination, the disease is preventable.


Generally, any substance introduced into the environment that adversely affects the usefulness of a resource or the health of humans, animals, or ecosystems.


Introduction into water, air, and soil of microorganisms, chemicals, toxic substances, wastes, or wastewater in a concentration that makes the medium unfit for its next intended use. Also applies to surfaces of objects, buildings, and various household and agricultural use products.

Polychromatic UV

A disinfection method that uses short-wavelength ultraviolet (UV-C) light from more than one color to kill or inactivate microorganisms by destroying nucleic acids and disrupting their DNA, leaving them unable to perform vital cellular functions.

Polymerase Chain Reaction

A method in which a target DNA sequence is preferentially replicated from a mixture of non-target sequences.


Human Polyomaviruses (HPyVs) are small, non-enveloped double-stranded DNA viruses. They are found in urine, feces and wastewater as a result are used as sewage source tracking viruses and are emerging as potential environmentally related transmission of viral induced cancer. These viruses had previously been classified as belonging to a single family: Papovaviridae (Papillomaviruses, Polyomaviruses and Vacuolating Simian Virus 40). In 2002 however, the International Committee of Viruses Taxonomy decided that enough evidence had been published to warrant the division of the Papovaviridae family into two families: Papillomaviridae and Polyomaviridae. Since then, the classification of both families has been evolving constantly due to an explosion of newly discovered viruses by innovative molecular detection methods.


Closeness of agreement between independent test results obtained under stipulated conditions


The percentage of a population that is affected with a particular disease at a given time.

Primary Sludge

The residue from primary treatment is a con-centrated suspension of particles in water called "primary sludge.

Proteolytic processing

Is a ubiquitous and irreversible post-translational modification involving limited and highly specific hydrolysis of peptide and isopeptide bonds of a protein by a protease.


Plant-like and animal-like eukaryotic unicellular organisms, primarily protozoa and fungi.

Protomeric units

The structural unit of an oligomeric protein.

Public Health

One of the efforts organized by society to protect, promote and restore the people´s health. It is the combination of sciences, skills and beliefs that is directed to the maintenance and improvement of the health of all the people through collective or social actions. Note: The programmes, services and institutions involved emphasize the prevention of disease and the health needs of the population as a whole. Public health activities changing technology and social values, but the goals remain the same: to reduce the amount of disease, premature death and disease-produced discomfort and disability in the population. Public health is thus a social institution, a discipline and a practice.


Poliovirus (Note: “PV” followed by a number indicates the serotype of the poliovirus, e.g., PV1 indicates a serotype 1 poliovirus; while a “W” preceding “PV” indicates that the poliovirus is wild).



Quantitative Microbial Risk Assessment


Quantitative real-time PCR


Quantitative real-time RT-PCR

Quantitative Microbial Risk Assessment

Method for assessing risk from specific microbial hazards through different exposure pathways. QMRA has four components: hazard identification; exposure assessment; dose-response assessment; risk characterization.

Quantitative Microbial Source Tracking

Refers to microbial source tracking using quantitative data on a particular microorganism, or any characteristic associated with that microorganism, in specific sources.

Quantitative PCR

Also known as real-time PCR. The principles of qPCR are similar to those of conventional PCR techniques with the exception that in each round of amplification the accumulation of PCR products is quantified.



Highly reactive groups of atoms that do not usually occur under terrestrial conditions but maybe relatively abundant in some molecular clouds, where collisions between reacting species happen only rarely.


An earthworm (Eisenia foetida) that lives near the surface of the soil and is commonly used for composting and for bait.

Restriction fragment length polymorphism

A difference in homologous DNA sequences that can be detected by the presence of fragments of different lengths after digestion of the samples with specific restriction endonucleases. RFLP, as a molecular marker, is specific to a single clone/restriction enzyme combination.


Adenine arabinoside (ara-A), a purine analogue that inhibits DNA synthesis; used as an antiviral agent to treat herpes simplex keratitis and keratoconjunctivitis.


It is a genotypic method that fingerprints bacteria based on sequence differences in genomic DNA, with steps including restriction enzyme digestion, electrophoresis, and probing via Southern blood.


The probability of adverse effects cause under specified circumstances by an agent in an organism, a population or an ecological system.

Risk analysis

Process for controlling situations where populations or ecological system could be exposed to a hazard. It usually comprises three steps, namely risk assessment, risk management, and risk communication.

Risk assessment

A qualitative or quantitative evaluation of the environmental and /or health risk resulting from exposure to a chemical or physical agent (pollutant); combines exposure assessment results with toxicity (or any other harmful impact) assessment results to estimate risk


Ribonucleic acid


Reverse transcription – polymerase chain reaction



Freedom from unacceptable risk of harm.


Saffold cardiovirus


Based on properties and reactions of serums.


The type of a microorganism determined by its constituent antigens.


Mixture of human excreta and water used to flush the excreta from the toilet and through the pipes; may also contain water used for domestic purposes


It is usually an underground channel or pipeline to carry off sewage and sometimes rainwater to wastewater treatment plants or to a natural waterway for disposal.

Sialic acid

Any of a group of amino carbohydrates that are components of mucoproteins and glycoproteins, especially in animal tissue and blood cells.


Simian Virus 40.


Relating to an ape or monkey.


A mixture of solids and water that settles to the bottom of latrines, septic tanks and ponds or is produced as a by-product of wastewater treatment (sludge produced from the treatment of municipal or industrial wastewater is not discussed)

Sludge Thickened

Thickening is a procedure used to increase the solids content of sludge by removing a portion of the liquid fraction. Thickening is generally accomplished by physical means including cosettling, gravity settling, flotation, centrifugation, gravity belt, and rotary drum

Sodium dodecyl sulfate

A synthetic organic compound with the formula CH3(CH2)11SO4Na. It is an anionic surfactant used in many cleaning and hygiene products.

Source apportionment

Identification of the origin of faecal contaminant(s) and their relative contribution to the total faecal contamination load.

Source Identifier

A microbial population that is particular to a specific animal host

Source sensitiviy criterion

The microorganisms used for MST should be present in comparable numbers in the feces of all subgrups of the target sources. In addition, markers should be highly abundant in source feces with concentrations comparable to or exceding the concentrataions of traditional fecal indicators

Source-associated species/pattern/marker

A species, pattern or marker that is indicative of a particular host species. ARA patterns of enterococci, ribotypes of E. coli and the human-specific DNA band of Bacteroides are examples of SPMs.

Source-specificity criterion

The microorganism use for MST should only be present in the fecal material of the respective source group considered. Consequently the target should be absent in the fecal material of all other source group, even in those that are closely related to the sepcific host.


Statistical measure that estimates the proportion of negatives which are correctly identified as such. It is complementary to the false positive rate


The reproductive body of an organism which is capable of giving rise to a new organism either directly or indirectly. A viable (able to live and grow) body regarded as the resting stage of an organism. A spore is usually more resistant to disinfectants and heat than most organisms.


Single stranded RNA


Any organization, group or individual that has an interest in or may be affected by a given policy decision or activity.


Document, established by consensus and approved by a recognized body (responsible for standards and regulations), that provides, for common and repeated use, rules, guidelines or characteristics for activities or their results, aimed at the achievement of the optimum degree of order in a given context. Regulation. Note: Standards should be based on the consolidated results of science, technology and experience, and aimed at the promotion community benefits.


Activity of establishing, with regard to actual or potential problems, provisions for common and repeated use, aimed at the achievement of the optimum degree of order in a given context. Note: In Particular, the activity consists of the processes of formulating, issuing and implementing standards.


An isolate or group of isolates exhibiting phenotypic and/or genotypic traits belonging to the same lineage, distinct from those of other isolates of the same species.


A microbial strain possessing a distinctive pattern market. Electrophoresis types, ribotypes, rep-PCR patterns an antibiotic resistance patterns all define bacterial subtypes. Coliphages types I-IV are also subtypes.


An organism, particle, or substance used to study the fate of a pathogen in a specific environment.


Periodic, continuous or repeated scrutiny of a phenomenon, situation or condition, generally using methods distinguish by their practicability, uniformity and frequently their rapidity rather than their complete accuracy. Note: Its mail purpose is to detect changes in trends or distribution in order to initiate investigate or control measures.

Surveillance of drinking-water quality

The continuous and vigilant public health assessment and review of the safety and acceptability of drinkingwater supplies.


Or the opposite term, decay—is described as a rate (loss of viability per unit of time), with the proportion of the number of live organisms over the total number of organisms at a given time. A number of factors, including temperature and moisture, influence this rate, and different microbes have different resistances to environmental stressors.


Simian Virus 40.



An antigen found in cells infected by an oncogenic virus.


A type of lymphocyte produced in bone marrow and differentiating in thymus tissue, that counteracts the presence of foreign antigens by a process of cell-mediated immunity in which the antigen is slowly destroyed.


A general taxonomic unit defined by a set of characteristics common to each member of that unit (e.g., family, genus, species, subspecies, and infra-species).

Tolerable Health Risk

Defined level of health risk from a specific exposure or disease that is tolerated by society, used to set health–based targets.

Total Maximum Daily Load

Is a calculation of the maximum amount of a pollutant that a waterbody can received and still meet water standards, and allocation of that amount to the pollutant's sources


Temperature-phased/thermophilic anaerobic digestion


Used in transport studies, examples include the use of coliphages or spores to trace groundwater movement or spore transport in aerosol.


An attempt to find the origin of faecal contaminant(s)


The transfer of living organs or tissue from one part of the body to another or from one individual to another.


The term “transport” assesses distance and spatial distribution in reference to the organism's concentration at a certain time after its release. It focuses on movement of an organism as distinct from viability.

Treated water

Water that has been subjected to any changes in characteristics, with a specific objective.

Trichodysplasia spinulosa

Is a type of human polyomavirus. It is associated with trichodysplasia spinulosa, a cutaneous eruption of spiny papules predominantly affecting the face that is associated with a distinctive histologic picture of abnormally maturing follicles with excessive inner root sheath differentiation and hyperkeratotic infundibula.

Trichodysplasia spinulosa-associatedPolyomavirus

Is a type of human polyomavirus. It is associated with trichodysplasia spinulosa, a cutaneous eruption of spiny papules predominantly affecting the face that is associated with a distinctive histologic picture of abnormally maturing follicles with excessive inner root sheath differentiation and hyperkeratotic infundibula.


Any of several chemical compounds in which halogen atoms replace three of the hydrogen atoms normally present ina methane molecule.


The turning or bending movement of an organism or a part of an organism in a particular direction in response to an external stimulus.


Trichodysplasia spinulosa-associated polyomavirus.


Well made by driving a tube into the earth to a stratum that bears water.


Cloudiness of a solution caused by the scattering of light by colloidal particles or by suspended precipitate or sediment.


A specific and discrete unit of information or character belonging to a strain displayed upon application of a strain-typing procedure.



Upflow anaerobic sludge blanket sewage treatment


United States Environmental Protection Agency


Validation (assay)

Comprehensive experiments that evaluate and document the quantitative performance of an assay, including sensitivity, specificity, accuracy, precision, detection limit, range and limits of quantification.

Validation (system)

The application of methods, procedures, tests and other evaluations, in addition to those used in operational monitoring, to determine compliance with the system design parameters and/or whether the system meets specified requirements (e.g. water quality testing, microbial reduction targets). Should take place when a new system is developed or new processes are added.


Vaccine-derived poliovirus, offspring of a type one, two or three oral polio vaccine strain that has accumulated at least 9, 6, or 9 nucleotide substitutions in its VP1 capsid protein relative to the corresponding vaccine strain).

Verification Monitoring

The application of methods, procedures, tests and other evaluations, in addition to those used in operational monitoring, to determine compliance with the system design parameters and/or with other specified requirements (e.g. concentration of pathogens or fecal indicators).


The process of breaking down organic material from waste through the use of worms, fungi and bacteria, to create a mixture of decomposing waste, bedding materials, and worm castings.


Adenine arabinoside (ara-A), a purine analogue that inhibits DNA synthesis; used as an antiviral agent to treat herpes simplex keratitis and keratoconjunctivitis.


The complete viral particle, found extracellularly and capable of surviving in crystalline form and infecting a living cell; it comprises the nucleoid (genetic material) and the capsid. Some virions also have a lipid envelope.


The presence of viruses in the urine.


A non-cellular microorganism that must infect a host cell to reproduce. A virus has two states: an intracellular state, when the virus may multiply and consists minimally of genetic material (double-stranded DNA, single-stranded DNA, double-stranded RNA, or single-stranded RNA); and an extracellular state, where the virus is also known as a viral particle or a virion, and has a protein coat in addition to the genome, and some viruses also have a lipid envelope.


Viral capsid protein. (Note: a number following “VP” indicates one of the four specific EV capsid proteins, e.g. “VP1” indicates viral capsid protein 1).



Liquid waste discharged from homes, commercial premises and similar sources to individual disposal systems or to municipal sewer pipes, and which contains human excreta and used water. When produced mainly by household and commercial activities, it is called domestic or municipal wastewater or domestic sewage. In this context, domestic sewage does not contain industrial effluents at levels that could pose threats to the functioning of the sewerage system, treatment plant, public health or the environment.

Water matrixes

The term water matrix refers to the composition of a water or wastewater with respect to major constiutents including dissolved ions, gross organics (BOD/COD/TOC), total dissolved solids and suspended materials such as turbidity or total suspended solids.  Understanding the water matrix is important because this can influence persistence of pathogens and the ability of treatment processes to remove them.

Water supply

Provision of water adeequate quality and sufficient quantity to fulfill health requirements for human consumption through a set of works, installations, pipelines and facilities that are appropriated operated and managed.


World Health Authority


World Health Organization


Wild poliovirus (Note: “WPV” followed by a number indicates the serotype of the WPV, e.g. WPV1 is a Wild type 1 poliovirus.


Wastewater treatment plant