Influenza pandemics occur when new influenza viruses appear that transmit efficiently between humans and to which a substantial proportion of the population is susceptible
On 30 May - 1 June 2012, ECDC and the WHO Regional Office for Europe (WHO/Europe) jointly held their second Annual Influenza Working Meeting in Warsaw, Poland. The main work undertaken by delegates in over 20 sessions and 70 talks and discussions was reviewing progress in the last 12 months and agreeing on the work for the coming year.