Sentinel surveillance


Sentinel surveillance is the "monitoring of rate of occurrence of specific conditions to assess the stability or change in health levels of a population". It also describes the study of disease rates in a specific cohort such as a geographic area or subgroup to estimate trends in a larger population.

Purpose

A sentinel surveillance system is used to obtain data about a particular disease that cannot be obtained through a passive system such as summarizing standard public health reports. Data collected in a well-designed sentinel system can be used to signal trends, identify outbreaks and monitor disease burden, providing a rapid, economical alternative to other surveillance methods.

Method

Sentinel systems involve a network of reporting sites, typically hospitals. Surveillance sites must offer:
Passive surveillance systems receive data from "all" health workers/facilities. Passive surveillance does not require health authorities to stimulate reporting by reminding health care workers. Passive surveillance is the most common type in tracking communicable diseases. Workers may receive the surveillance training in how to complete surveillance forms. Passive surveillance is often incomplete because of the limited reporting incentives.

Systems

Sentinel systems collect data on Haemophilus influenzae type b, meningococcus and pneumococcus.
Because sentinel surveillance is conducted only at selected locations, it is not as appropriate for use on rare diseases or outbreaks distant from sentinel sites.

COVID-19

The state of Hawaii conducts a sentinel surveillance program for COVID-19. From 3/1-4/11/2020, Hawaii's system detected 23 cases of COVID-19 among 1,084 specimens tested. Samples were selected to match the state's geographic and age distribution.