To observe and to describe the safety during Days 0 to 21 following injection of the 2004-2005 formulation of the inactivated, split-virion influenza vaccine Fluzone® in subjects aged 18-59 years and subjects aged ≥ 60 years.

To measure and to describe the immune response (antibodies to hemagglutinin) 21 days following injection of the 2004-2005 formulation of the inactivated, split-virion influenza vaccine Fluzone®, in subjects aged 18-59 years and subjects aged ≥ 60 years.

The time of onset and duration of local and systemic solicited reactions will be assessed and reported. Unsolicited adverse events (including serious adverse events) will be collected and categorized throughout the study period.

Antibody levels will be evaluated by hemagglutination inhibition (HI) assay from sera obtained pre-vaccination (Day 0) and 21 days post-vaccination, for antigens from the 2004-2005 influenza virus strains: A/New Caledonia/20/99 (H1N1), A/Wyoming/03/2003 (H3N2), and B/Jiangsu/10/2003.

Inclusion Criteria :

• Participant aged 18 years or older.
• Participant able to attend scheduled visits and to comply with the study procedures during the entire duration of the study.
• Participant is in reasonably good health as assessed by the investigator.
• Participant willing and able to meet protocol requirements.
• Participant willing and able to give informed consent.

Exclusion Criteria :

• Self-reported allergy to egg proteins, chicken proteins, or one of the constituents of the vaccine, such as thimerosal or formaldehyde.
• An acute illness with or without fever (temperature >100.4°F) in the 72 hours preceding enrollment in the trial.
• Clinically significant findings in vital signs (including temperature >100.4°F) on review of systems.
• Self-reported history of severe adverse event to any influenza vaccine.
• Vaccination against influenza in the 6 months preceding enrollment in the study.
• Any vaccination in the 14 days preceding enrollment in the study or scheduled between Visit 1 and Visit 3.
• Participation in any other experimental drug or vaccine trial within the 30 days preceding enrollment into the study.
• Immunogenicity or immunosuppressive therapy (including systemic steroid use for 2 weeks or more), cancer chemotherapy, or radiation therapy at the time of enrollment, planned during the period of this study, or at any time within the past 3 months.
• Receipt of blood or blood products within the 3 months preceding enrollment in the study.
• Diabetes mellitus requiring pharmacological control.
• Any condition that in the opinion of the investigator would pose a health risk to the subject if enrolled, or could interfere with the evaluation of the vaccine.
• Person deprived of freedom by an administrative or court order (having legal or medical guardian).
• For women of childbearing age, a positive urine pregnancy test, breast feeding, or not using a medically approved and reliable form of contraception (oral contraceptives or double barrier method) for the duration of the trial.