Pandemics arise when a new virus emerges which is capable of spreading in the worldwide population. Unlike ordinary seasonal influenza that occurs every winter in the UK, pandemic flu can occur at any time of the year.
The most devastating influenza pandemic in recorded history occurred in 1918-19, when a completely new influenza virus subtype (influenza A/H1N1, "Spanish flu") emerged and spread around the globe in around four to six months. Several waves of infection occurred over two years, killing an estimated 40-50 million people. Two further influenza pandemics occurred in the 20th century: in 1957 (influenza H2N2, "Asian flu") and in 1968 (influenza H3N2, "Hong Kong flu").
Most recently the influenza A(H1N1)pdm09 'swine flu' pandemic virus emerged in Mexico in 2009 causing mild/asymptomatic disease in the majority of cases but severe illness and death in a small proportion of cases, particularly in more vulnerable groups. The threat of a more severe and disrupting pandemic remains and the UK has to be prepared for such an event.
7 February 2013 - Influenza Preparedness Update Issue 6 Feb 2013 (PDF, 277 KB)
5 November 2012 - Influenza Preparedness Update Issue 5 Nov 2012 (PDF, 143 KB)
30 October 2012 - HPA Pandemic Influenza Strategic Framework (PDF, 364 KB) This document describes the HPA's strategic roles and actions for preparation and response to an influenza pandemic and the Agency's responsibilities in the context of the Department of Health’s UK Influenza Pandemic Influenza Strategy 2011
25 September 2012 - Influenza Preparedness Update Issue 4 Sept 2012 (PDF, 150 KB)
20 April 2012 - Health and Social Care Influenza Pandemic Preparedness and Response [External link] - Operational guidance on the implementation of the UK Influenza Pandemic Preparedness Strategy 2011. The guidance for health and social care workers is intended to support local preparedness and response planning in England during the transition period through to 2013 .
10 November 2011 - The UK Influenza Pandemic Preparedness Strategy 2011 [External link] describes the Government's strategic approach for responding to an influenza pandemic. It updates the clinical, health and scientific advice and information contained in 'Pandemic flu: a national framework for responding to an influenza pandemic 2007' and replaces that document.