Weekly influenza surveillance overview, 2-8 April 2012, week 14

The 2011/12 influenza season started late, has been without any clear geographic progression across Europe and transmission has been declining in a number of countries since around week 9.The decrease in the proportion of influenza-positive sentinel specimens together with the growing number of countries reporting continuously decreasing trends in the incidence of ILI or ARI indicate that the epidemic peak has passed in almost all European countries. However, the proportion of positive specimens indicates that the level of influenza circulation is still considerable in Europe. As often observed late in the season, the proportion of influenza B viruses among detected influenza viruses has been increasing over the past eight weeks.