Monitoring and Surveillance

Health Hygiene & Sanitation

Lesson 09 : Concept Of Control And Prevention Of Diseases

Monitoring and Surveillance

The two terms are often used synonymously. But in public health practice, the two terms are different.


It is the performance and analysis of routine measurements aimed at detecting changes in the environment or health status of population.

  • Air pollution
  • Water quality
  • Growth, nutritional statuses are all monitored.

Monitoring also refers to on-going measurement of performance of health service or a health professional or of the extent to which patients comply with or adhere to advice from health professionals.


Surveillance means watch over with great attention, authority and with suspicion.
Surveillance is also referred as the continuous scrutiny of factors that determine the occurrence and distribution of disease and other conditions of ill health.

Objectives of Surveillance

  • To provide information about new and changing trends in the health status of a population. E.g. Morbidity, mortality, nutritional status or other indicators, environmental hazards, health practices and other factors that may affect health.
  • To provide feedback which may be expected to modify policy and system leading to redefinition of objectives.
  • To provide timely warning of public health disasters so that interventions can be mobilized.

Sentinel Surveillance

Sentinel Surveillance means a method of identifying missing cases and thereby supplementing the notified cases. The data is extrapolated to the entire population.
Advantages are

  • Reporting biases are minimized
  • Feedback of information to the providers is simplified.

Sentinel Surveillance agencies must be interested and competent institutions in selected areas to report the cases of disease in their areas. This system will provide valuable and detailed information than traditional notification system.

Evaluation of Control

Comparison of results with the intended objectives is evaluation.

Assessment of how well a programme is performing.

Evaluation should be considered during planning and execution of the programme. It may be crucial in identifying the health benefits derived like impact on morbidity, mortality, sequalae, patient satisfaction.
Evaluation can be useful

  • in identifying performance difficulties
  • To generate information for other purposes
  • To attract attention to a problem
  • Extension of control activities
  • Training and patient management.
Last modified: Monday, 23 April 2012, 9:31 AM