Annual Study to Investigate Inactivated Virosomal Influenza Vaccine for the 2006/2007 Influenza Season in Europe.

Influenza (flu) viruses change continuously, therefore also the parts of viruses used in influenza vaccines can vary from year to year. In Europe, manufacturers/marketing holders of these vaccines are required to be involved in ongoing clinical trials and to present the results to the competent authorities each year. The current study is a phase IIIa clinical trial with a commercially available virosomal vaccine (Invivac®) supplied in pre filled syringes. It is part of the ongoing clinical trial program for Invivac® and will be done to assess the immunogenicity and safety and tolerability of next season's trivalent influenza virosomal vaccine in two groups of healthy subjects: subjects aged \>= 18 and \= 61 years of age (elderly).