Immunogenicity and Safety Study of GlaxoSmithKline (GSK) Biologicals' Trivalent Split Virion Influenza Vaccine Fluviral™ (2013-2014 Season) in Adults Aged 18 Years and Older

Inclusion Criteria: * Subjects who, in the opinion of the investigator, can and will comply with the requirements of the protocol. * A male or female 18 years of age and older at the time of the first vaccination. * Written informed consent obtained from the subject. * Healthy subjects or subjects with well-controlled chronic disease, as established by medical history and clinical examination before entering into the study. * Female subjects of non-childbearing potential may be enrolled in the study. * Non-childbearing potential is defined as pre-menarche, current tubal ligation, hysterectomy, ovariectomy or post-menopause. * Female subjects of childbearing potential may be enrolled in the study, if the subject: * has practiced adequate contraception for 30 days prior to vaccination, and * has a negative pregnancy test on the day of vaccination, and * has agreed to continue adequate contraception during the entire treatment period and for 2 months after completion of the vaccination dose. Exclusion Criteria: * Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine 30 days preceding the dose of study vaccine, or planned use during the study period. * Chronic administration (defined as more than 14 days in total) of immunosuppressants or other immune-modifying drugs within six months prior to the vaccine dose. For corticosteroids, this will mean prednisone ≥ 20 mg/day, or equivalent. Inhaled and topical steroids are allowed. * Any administration of a long-acting immune-modifying drug (e.g. rituximab, infliximab etc.) within 6 months before study start, or planned administration during the study period. * Administration of any influenza vaccine within 6 months preceding the study start or planned use of such vaccines during the study period. * Administration of any other vaccine(s) within 30 days prior to study enrollment or during the study period. * Clinically or virologically confirmed influenza infection within the 6 months preceding the study vaccination. * Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination (no laboratory testing required): * History of human immunodeficiency virus (HIV) infection, * Cancer or treatment for cancer, within 3 years of study enrollment. Persons with a history of cancer who are disease-free without treatment for 3 years or more are eligible. * Acute disease and/or fever at the time of enrollment. * Acute disease is defined as the presence of a short term, moderate or severe illness, with or without fever. * Fever is defined as temperature ≥ 38.0°C/100.4°F for oral, axillary or tympanic route. The preferred route for recording temperature in this study will be oral. * Subjects with a minor illness (such as mild diarrhea, mild upper respiratory infection) without fever may, be enrolled at the discretion of the investigator. * Significant acute or chronic, uncontrolled medical or psychiatric or neurological illness. "Uncontrolled" is defined as: * Requiring institution of new medical or surgical treatment within one month prior to study enrollment, or * Requiring the re-institution of a previously discontinued medication or medical treatment within one month prior to study enrollment, or * Requiring a change in medication dosage in the one month prior to study enrollment due to uncontrolled symptoms or drug toxicity (elective dosage adjustments in stable subjects are acceptable), or * Hospitalization or an event fulfilling the definition of a SAE within one month prior to study enrollment. * Acute or chronic, clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by physical examination or laboratory screening tests. * Subjects who participated in the registration trial \[116664 (FLU Q-TIV-014)\] for Fluviral™ 2012/2013 conducted in the 2012-2013 season. * Presence of blood dyscrasias, including hemoglobinopathies and myelo- or lymphoproliferative disorder. * A history of any demyelinating disease including Multiple Sclerosis and Guillain-Barré syndrome. * Administration of immunoglobulins and/or any blood products within the 3 months preceding the dose of study vaccine or planned administration during the study period. * Any known or suspected allergy to any constituent of Fluviral™ and/or a history of anaphylactic type reaction to consumption of eggs, and/or reactions to products containing mercury. * A history of severe adverse reaction to a previous influenza vaccination. * Pregnant or lactating female. * History of chronic alcohol consumption and/or drug abuse as deemed by the investigator to render the potential subject unable/unlikely to provide accurate safety reports. * Any condition which, in the opinion of the investigator, prevents the subject from participation in the study or would make the intramuscular injection unsafe.