 Influenza flu viruses change continuously, therefore also the parts of viruses used in influenza vaccines can vary from year to year. The current study is a phase III A clinical trial with a commercially available vaccine Influvac supplied in pre filled syringes. The objective of this study is to investigate the immunogenicity and safety and tolerability of the changed influenza vaccine virus composition in two groups of subjects in good health: subjects aged 18 and 60 years and subjects 61 years of age elderly. 