Immunogenicity and Safety of the Inactivated, Split-Virion Influenza Vaccine, Northern Hemisphere 2008-2009 Formulation

Inclusion criteria

• Aged 18 to 60 years or 61 years and older on the day of inclusion
• Provision of a signed informed consent
• Able to attend all scheduled visits and comply with all trial procedures
• For a woman of child-bearing potential: avoid becoming pregnant (use of an effective method of contraception or abstinence) for at least 4 weeks prior to vaccination, until at least 21 days after vaccination

Exclusion criteria

• For a woman of child-bearing potential, known pregnancy or positive urine pregnancy test at visit 01
• Febrile illness (temperature ≥ 37.5°C) or moderate or severe acute illness/infection on the day of vaccination, according to Investigator judgment
• Breast-feeding woman
• Participation in another clinical trial investigating a vaccine, drug, medical device, or medical procedure in the 4 weeks preceding the trial vaccination
• Planned participation in another clinical trial during the present trial period
• Known or suspected congenital or acquired immunodeficiency, immunosuppressive therapy such as anti-cancer chemotherapy or radiation therapy within the preceding 6 months, or long-term systemic corticosteroids therapy
• Known systemic hypersensitivity to egg proteins, chick proteins, neomycin, formaldehyde and octoxinol 9, or to any of the vaccine components, or history of a life-threatening reaction to the trial vaccine or a vaccine containing any of the same substances
• Chronic illness at a stage that could interfere with trial conduct or completion, in the opinion of the Investigator
• Current alcohol abuse or drug addiction that may interfere with the subject's ability to comply with trial procedures
• Receipt of blood or blood-derived products in the past 3 months, that might interfere with the assessment of immune response
• Receipt of any vaccine in the 4 weeks preceding the trial vaccination
• Planned receipt of any vaccine in the 3 weeks following the trial vaccination
• Previous vaccination against influenza in the previous 6 months
• Thrombocytopenia, bleeding disorder or anticoagulants in the 3 weeks preceding inclusion contraindicating intramuscular vaccination
• Known Human Immunodeficiency Virus (HIV), Hepatitis B surface antigen or Hepatitis C seropositivity
• Subject deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized without his/her consent.