All marketed influenza vaccines are injected by the intramuscular (IM) route. This study will test whether an influenza vaccine is effective when injected by a route other than into the muscle. In order to prove this, the amount of antibodies in the blood will be measured before and after vaccination. In addition, the safety of both influenza vaccines will be tested by evaluating all serious reactions occurring after vaccination. The vaccine injected in this study is similar to the sponsor's marketed intramuscular influenza vaccine (Vaxigrip). In addition, the safety of both influenza vaccines administered by different routes will be tested by evaluating all adverse events and especially all serious reactions.