Epidemiological surveillance

Epidemiological surveillance is the discipline of continuously gathering, analysing, and interpreting data about diseases, and disseminating conclusions of the analyses to relevant organisations. As such, it is a key element in epidemiology.

This term may be used in two ways. In broader sense, surveillance has been equated with the routine health information system which gives idea about the total health situation. in narrower sense, it is used to refer to specific information system pertaining to specific disease or any other health related event.

Purpose

1. assessing magnitude of problem

2. monitoring implementation of health programs

3. understanding local epidemiology of the problem

4. assessing changes in trend of disease or its distribution

5. identifying specific groups at risk

6. to enable predictions about pattern of occurrence of diseases

7. in assessing the impact of the programme intervention for control of diseases

Methods

Passive surveillance: It is the routine reporting of the cases of diseases reaching health care facilities for treatment or service.No special effort is made to find unsuspected disease incidents. Passive surveillance will usually only detect disease in those who get sick, meaning that healthy carriers and long incubation periods combined with passive surveillance can maintain a reservoir of undiscovered disease carrying agents.

Active surveillance: In this special search is done for finding cases in the community mainly through door to door surveys.

Sentinel surveillance: It is a reporting system based on selected institutions or individual that provide regular, complete reports on one or more diseases occurring ideally in a defined attachment. it also provides additional data on cases.

See also

• Real-Time Outbreak and Disease Surveillance (RODS)