Study Comparing the Immune Response of Fluarix and Fluzone Influenza Vaccines

Inclusion Criteria: All adults 18 years and older. Subjects who the investigator believes can and will comply with the requirements of the protocol (e.g., return for follow-up visit and completion of the diary cards) should be enrolled in the study. Written informed consent obtained from the subject. If the subject is female, she must be of non-childbearing potential, i.e. either surgically sterilized or one year post-menopausal; or, if of childbearing potential, she must be abstinent or have used adequate contraceptive precautions . Exclusion Criteria: Use of any investigational or non-registered product (drug or vaccine) within 30 days preceding the administration of the study vaccine, or planned use during the study period. Has received any other licensed vaccines within 2 weeks (for inactivated vaccines) or 4 weeks (for live vaccines) prior to enrollment in this study. History of hypersensitivity to a previous dose of influenza vaccine. History of allergy or reactions likely to be exacerbated by any component of the vaccine(s) including egg, chicken protein, gelatine, formaldehyde, gentamicin sulphate, thimerosal or sodium deoxycholate. Acute disease at the time of enrollment. (Acute disease is defined as the presence of a moderate or severe illness with or without fever. All vaccines can be administered to persons with a minor illness such as diarrhea, mild upper respiratory infection with or without low-grade febrile illness, i.e. Oral temperature <37.5°C (99.5°F) / Axillary temperature <37.5°C (99.5°F)). History of Guillain Barré syndrome within 6 weeks of prior receipt of inactivated influenza virus vaccine. Pregnancy and lactating females.