The influenza season has started in a number of European countries

Increased influenza activity was reported in 13 European countries in week 2 of 2008: Austria, Bulgaria, France, Hungary, Ireland, Italy, Luxembourg, the Netherlands, Portugal, Slovenia, Spain, Switzerland and the UK. Based on historical trends, influenza activity is expected to increase in more countries in the coming weeks and to move gradually eastwards and northwards in Europe [1]. Influenza activity is mainly associated with type A influenza virus, subtype H1, which usually causes only mild- to medium-intensity influenza epidemics.