A Trial to Assess the Immunogenicity and Safety of the Trivalent Virosomal Influenza Vaccine, Formulation of 2012-2013, in Non-Elderly Adults and Elderly Subjects

Inclusion Criteria:

1. Males and non-pregnant females and aged no less than 18 years;
2. Willing and able to adhere to visit schedules and all study requirements;
3. Subjects are willing to provide the signed study-specific informed consent.

Exclusion Criteria:

1. Subject or his/her family is employed by the participated hospital;
2. Subjects received influenza vaccine within the previous 6 months;
3. History of hypersensitivity to eggs or hen's protein, polymyxin B, or neomycin, or similar pharmacological effects to study vaccine;
4. Personal or family history of Guillain-Barré Syndrome;
5. An acute febrile illness within 1 week prior to vaccination;
6. Current upper respiratory illness, including the common cold or nasal congestion within 72 hours;
7. Subjects with influenza-like illness as defined by the presence of fever (temperature no less than 38°C) and at least two of the following four symptoms: headache, muscle/joint aches and pains (e.g. myalgia/arthralgia), sore throat and cough;
8. Female subjects who are pregnant, lactating or likely to become pregnant during the study; women of childbearing potential disagree to use an acceptable method of contraception (e.g., hormonal contraceptives, intrauterine device (IUD), barrier device or abstinence) throughout the study;
9. Treatment with an investigational drug or device, or participation in a clinical study, within 3 months before study vaccination;
10. Immunodeficiency, or under immunosuppressive treatment;
11. Receipt of live virus vaccine within 1 month prior to study vaccination or expected receipt within 1 month of study vaccination; receipt of any inactivated vaccine within 2 weeks prior to study vaccination or expected receipt within 1 month of study vaccination;
12. Receipt of any blood products, including immunoglobulin in the prior 3 months;
13. Underlying condition in the investigators' opinion may interfere with evaluation of the vaccine;
14. Significant chronic illness for which inactivated influenza vaccine is recommended or commonly used.