Early detection, assessment and response to acute public health events: implementation of early warning and response with a focus on event-based surveillance

Overview

In the last decades, the world has undergone rapid changes including demographic explosions and massive urbanization, population movement, increase in international trade and travel, emergence of new pathogens, use of techniques which induce new risks, chemical and nuclear accidents, environmental disasters and introduction of the threat of criminal acts and bioterrorism. 

To respond to this changing environment, the International Health Regulations (IHR) were revised in 2005. The IHR expand usual infectious disease notification to include surveillance of public health events from various origins (e.g. nuclear, chemical or unknown), and prompts Member States to develop the capacities of their surveillance systems to detect, assess, notify and respond to all acute health events or health risks that may constitute a threat to human health. As noted, “To comprehensively meet the early warning and alert requirements of the IHR, there is a need to strengthen and develop both routine, or indicator-based, surveillance and event-based surveillance”.