Safety of a Influenza Vaccine Produced Either in Mammalian Cell Culture or in Embryonated Hen Eggs in Adults and Elderly With and Without Underlying Medical Conditions, and Immunogenicity in a Subset of Subjects With Underlying Medical Conditions

Inclusion Criteria:

1. Subjects 18 years of age and above, mentally competent, willing and able to give informed consent prior to study entry;
2. Able to comply with all study procedures and requirements.

Exclusion Criteria:

1. History of any anaphylaxis, serious vaccine reactions, or hypersensitivity to any vaccine component;
2. Fatal prognosis of an underlying medical condition (<12 months life expectancy);
3. History of Guillain-Barre syndrome;
4. Bleeding diathesis or receiving anticoagulants of the coumarin type;
5. Hospitalization or residence in a nursing care facility;
6. Planned to receive seasonal influenza vaccine outside of this study;
7. Receipt of another vaccine within 2 weeks (for inactivated vaccines) or 4 weeks (for live vaccines) prior to enrollment in this study;
8. Fever (defined as axillary temperature ≥38.0°C) or any acute illness within 3 days prior to study vaccination;
9. Receipt of another investigational agent within 30 days prior to enrollment in the study or before completion of the safety follow-up period in another study, whichever is longer, and unwilling to refuse participation in another clinical study through the end safety follow up period of the study;
10. Any condition, which, in the opinion of the investigator, might prevent the subject from participation or interfere with the evaluation of the study objectives;
11. Females who were pregnant or nursing (breastfeeding) mothers, or females of childbearing potential who were sexually active and had not used or did not plan to use acceptable birth control measures during the first 3 weeks after vaccination. Oral, injected or implanted hormonal contraceptive, diaphragm or condom with spermicidal agent or intrauterine device were considered acceptable forms of birth control.