Epidemic intelligence integrates indicator-based and event-based components. ‘Indicator-based surveillance’ refers to structured data collected through routine surveillance systems.  The ‘event-based surveillance’ refers to unstructured data gathered from formal and informal sources, such as the media and scientific publications. The purpose of both these components of epidemic intelligence is to quickly identify any event which might become a public concern. The epidemic intelligence covers risk assessment and risk monitoring.

The objective of epidemic intelligence is to produce timely, validated and actionable intelligence on events related to communicable diseases or of unknown origin that are of interest for public health and health authorities. The process can be divided into early detection of new threats and events, and monitoring the threats that have already been identified, including potential threats.

Early detection comprises six elements:

  1. Screening news, official reports or notes and rumours relevant from a European perspective in order to distinguish the meaningful information signals by applying specified criteria.
  2. Filtering the events to identify potential public health events of European interest.
  3. Validating the events that originate from unofficial sources, by cross-checking with official and/or reliable media sources to ensure that the event detected is real and fully understood.
  4. A validated event will then be analysed to capture the full information available about the event, including epidemiological data, facts related to exposures and contextual information.
  5. Based on the analysis, an assessment is made to estimate the risk associated with the event.
  6. Finally, communication and documentation of the identified threats are an integral part of the epidemic intelligence, throughout the five steps above.

Monitoring identified threats refers to the active follow-up of all relevant information directly related to the concerned threat. This iterative process continues until the threat is considered to have subsided or until all appropriate public health measures have been implemented.

Of course in a rapidly evolving situation professional judgement should be exercised and it may be appropriate under severe time constraints to skip some of the above-mentioned steps in order to quickly share information. However, if epidemic intelligence can be gathered systematically as described above, the outcome is a better informed decision and more effective action.

Reference:

Tutorial ECDC on Epidemic Intelligence