Microbial Risk Assessment of Pathogens in Water

  • Gertjan Medema


Water can transmit infectious diseases. Water can be transport vehicle. A range of pathogenic microorganisms is shed into the water cycle by infected hosts (man or animal) and transported to new hosts by the water cycle. Water can also be a niche for (opportunistic) pathogens. These pathogens grow in water ecosystems (natural or man-made) and may infect humans that come into contact with this water. Management of the risk of waterborne disease transmission requires knowledge about the nature of the pathogens, their potential growth, fate and transport in the water cycle, the routes of exposure to humans and the health effects that may result from this exposure in the human population, as well as the effect of potential mitigation measures.


Risk Assessment Hazardous Event Gray Water Wastewater Reuse Health Target 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Dose-response assessment

The determination of the relationship between the magnitude of exposure (dose) to a microbiological agent and the severity and/or frequency of the associated adverse health effects (response).

Exposure assessment

Qualitative and/or quantitative evaluation of the likely intake of microbial hazard via all relevant sources or a specific source.


Concentration or amount of an infectious microorganism that reaches the target population, or organism usually expressed in numerical terms of substance, concentration, duration, and frequency.

HACCP: Hazard Analysis Critical Control Point

A system that identifies, evaluates, and controls hazards that are significant for water safety.


A biological agent with the potential to cause an adverse health effect.

Hazard identification

The identification of microbiological and biological agents capable of causing adverse health effects that may be present in water.

Hazardous event

An event that may lead to the presence of a hazard in drinking water.

Health effects

Changes in morphology, physiology growth, development or life span of an organism, which results in impairment of functional capacity or impairment of capacity to compensate for additional stress or increase in susceptibility to the harmful effects or other environmental influences.


Colonization of a human (tissue) by a microorganism.

Infectious disease

Colonization by a pathogenic microorganism leading to overt symptoms of disease.


A microorganism capable of causing disease.


Quantitative Microbial Risk Assessment.

Risk assessment

A scientifically based process consisting of the following steps: (1) hazard identification, (2) exposure assessment, (3) effect assessment, and (4) risk characterization.

Risk characterization

The qualitative and quantitative estimation, including attendant uncertainties of the probability of occurrence and severity of known or potential adverse health effects in a given population based on hazard identification, hazard characterization, and exposure assessment.


The likelihood of occurrence of an adverse health effect consequent to a hazard in drinking water.


Lack of knowledge about specific factors, parameters, or models. Uncertainty includes parameter uncertainty (measurement errors, sampling errors, systematic errors), model uncertainty (uncertainty due to necessary simplification of real-world processes, mis-specification of the model structure, model misuse, use of inappropriate surrogate variables), and scenario uncertainty (descriptive errors, aggregation errors, errors in professional judgment, incomplete analysis).


Intrinsic heterogeneity in a population, process, or parameter.

Water Safety Plan (WSP)

A management plan developed to address all aspects of water supply that are under the direct control of the water supplier focused on the control of water production, treatment, and distribution to deliver drinking water.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Water Quality & HealthKWR Watercycle Research InstituteNieuwegeinThe Netherlands
  2. 2.Sanitary EngineeringDelft University of TechnologyDelftThe Netherlands

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