In October 2009, the German Advisory Board on Immunization (STIKO) recommended vaccination against PIA for selected risk groups. For children, it was recommended that primarily children above six months of age with underlying diseases, such as chronic diseases of the air ways, cardiovascular system, liver or kidneys, should be vaccinated. Secondarily, healthy children should be vaccinated as well [16] . The first PIA vaccine was available in Germany at the end of October 2009. In our study, 40 (43%) children suffered from underlying diseases and, hence, ideally should have been vaccinated against influenza. Of these 40 children, two children were younger than six months and 16 children became ill before the PIA vaccine was available. Of the remaining 22 children with underlying diseases only two (9%) had received a PIA vaccination. Only for one child (2%) out of 51 children without predisposing factors aged above six months a PIA vaccination was reported. The low PIA vaccination coverage found in our study is confirmed by results from cross-sectional surveys in children <14 years of age in Germany (8% coverage) [17] , and from a German surveillance study on severe PIA cases <15 years of age admitted to intensive care units (9% coverage) [7] .