Patent ID: 8557251

Claim:
A method for inducing a protective immune response in a human population of at least 18 years old comprising administering intradermally a single dose of a trivalent, split or subunit influenza vaccine antigen preparation using a short needle device, wherein the single dose results in said protective immune response meeting at least one criterion chosen from the group of: (1) a protection rate of >70% in adults of 18-60 years old or of >60% in elderly people of above 60 years old; (2) a seroconversion rate of >40% in adults of 18-60 years old or of >30% in elderly people of above 60 years old; and (3) a conversion factor of >2.5 HI titres in adults of 18-60 years old or of >2.0 HI titres in elderly people of above 60 years old, for each influenza strain.