Public Health Emergency Preparedness and Response

What is a public health threat?

A public health threat (or major incident) is an event, condition or agent which has the potential to rapidly harm an exposed population sufficiently to lead to a crisis.

Examples of potential public health threats include SARS (severe acute respiratory syndrome), pandemic influenza, toxic industrial fires, factory explosions, food or water contamination, release of a chemical, biological or radioactive agent and severe flooding.

Departments of Public Health participate in emergency preparedness and planning and contribute to the prevention of major emergencies at local and national level. 

Departments of Public Health can play a key role in the management of public health threats (see A Framework for Major Emergency Management).

How are public health threats detected?

Early detection of public health threats is an important function of Departments of Public Health and the Health Protection Surveillance Centre (HPSC). Epidemic intelligence includes monitoring and early warning systems to give early triggers of possible threats. This includes:

  • notifiable disease surveillance, where certain diseases are notified by law to the Medical Officer of Health in the Departments of Public Health
  • regional outbreak reporting and computerised collation for a national picture
  • event-based surveillance [from many varied sources including the media, Departments of Public Health and international alert systems (e.g. European Early Warning and Response System (EWRS), ECDC EPIS system, and the WHO Alert system under the International Health Regulations)]
  • enhanced surveillance programmes where clinicians, laboratory and public health staff work to gather extra data to give a comprehensive picture of the threat from any particular disease
  • liaison with colleagues in veterinary, marine, agriculture, environmental health and other agencies.

What is the response to a public health threat?

In the event of a public health emergency, the Departments of Public Health, working with other HSE colleagues and local response agencies, aim to:

  • protect public health and well-being
  • limit disruption to society
  • minimise the impact on the health and social system.


The role of Departments of Public Health following a public health major incident include:

  • identification of the population who have been exposed to the threat
  • assessment of the risk to public health
  • risk communication and guidance to key health professionals
  • risk communication to the public to address concerns, provide information and advice
  • advice on control measures to protect public health
  • short term and long term monitoring of those exposed if appropriate.

Preparing for Major Emergencies Handbook

We can all contribute to preventing and dealing with major emergencies, by using the "Preparing for Major Emergencies Handbook"