The present study aims to evaluate safety and immunogenicity of two doses, administered three weeks apart, and a 6 month booster dose, of two influenza vaccines containing 7.5 micrograms or 15 micrograms of H5N1 influenza antigen, and of a non-adjuvanted influenza vaccine containing 15 micrograms of H5N1 influenza antigen, in adults

Inclusion Criteria:

• Male and female volunteers 18-60 years of age

Exclusion Criteria:

• Any auto-immune disease or other serious acute, chronic or progressive disease
• Hypersensitivity to eggs, chicken protein, chicken feathers, influenza viral protein, neomycin or polymyxin or any other component of the vaccine
• History of neurological symptoms or signs, or anaphylactic shock following administration of any vaccine
• Within the past 7 days, they have experienced any acute disease or infections requiring systemic antibiotic or antiviral therapy