The present study will evaluate the safety and immunogenicity in healthy people (non-elderly adult and elderly subjects) after one intramuscular (IM) dose of trivalent subunit inactivated flu vaccine.

Inclusion Criteria:

• Males and females volunteers of 18 years of age or older, mentally competent, willing and able to give written informed consent prior to study entry
• Individuals able to complain with all the study requirements
• Individuals in good health as determined by the outcome of medical history, physical examination and clinical judgment of the investigator.

Exclusion Criteria:

• Individuals with behavioral or cognitive impairment or psychiatric disease that, in the opinion of the investigator, may interfere with the subject's ability to participate in the study
• Individuals with any serious chronic or acute disease (in the judgment of the investigator), including but not limited to: cancer, advanced congestive heart failure, chronic obstructive pulmonary disease (COPD), autoimmune diseases, acute or progressive hepatic and renal disease, severe neurological or psychiatric disorder and severe asthma
• Individuals with history of any anaphylactic reaction and/or serious allergic reaction following a vaccination, a proven hypersensitivity to any component of the study vaccine (e.g. to eggs/eggs product as well as ovalbumin, chicken protein, chicken feathers, influenza viral protein, kanamycin and neomycin sulphate)
• Individuals with known or suspected impairment/alteration of immune function resulting, for example, from: receipt of immunosuppressive therapy within the past 60 days and for the full length of the study, receipt of immunostimulants, receipt of parenteral immunoglobulin preparation, blood products and/or plasma derivates within the past 3 months and for the full length of the study and suspected or known human immunodeficiency virus (HIV) infection or HIV-related disease
• Individuals with known or suspected history of drug or alcohol abuse
• Female who are pregnant or nursing (breastfeeding) mothers or females of childbearing potential do not plan to use acceptable birth control measures for the whole duration of the study
• Individuals with history or any illness that, in the opinion of the investigator, might interfere with the results of the study or pose additional risk to the subjects due to participation in the study
• Individuals within the past 6 months, they have had any seasonal or pandemic laboratory confirmed influenza disease and received any seasonal or pandemic influenza vaccine
• Individuals with any acute or chronic infections requiring systemic antibiotic treatment or antiviral therapy within the last 7 days
• Individuals that have experienced fever (i.e., axillary temperature ≥ 38°C) within the last 3 days of intended study vaccination
• Individuals participating in any clinical trial with another investigational product 4 weeks prior to first study visit or intent to participate in another clinical study at any time during the conduct of this study
• Individuals who received any other vaccines within 4 weeks prior to enrollment in this study or who are planning to receive any vaccine within 4 weeks from the study vaccines
• Individuals who have ever received blood/blood products and/or plasma derivatives or any parenteral immunoglobulin preparation in the past 12 weeks and for the full length of the study
• Individuals who are part of study personnel or close family members conducting this study
• Individuals with a bleeding diathesis or conditions associated with prolonged bleeding time that in the investigator's opinion would interfere with the safety of the subject
• BMI > 35 kg/m2