Immunogenicity and Safety Study of FSME-IMMUN 0.5 mL in Adult Subjects Previously Vaccinated According to a Rapid Immunization Schedule

Inclusion Criteria: Male and female subjects will be eligible for participation in this study if they: * Understand the nature of the study, agree to its provisions and provide written informed consent (assent if the subjects is under 18 years of age); * Provide the written informed consent of their parents / legal guardian (if the subject is under 18 years of age); * Are aged \>= 16 years (from the 16th birthday) at screening; * Are clinically healthy, (i.e. the physician would have no reservations vaccinating with FSME-IMMUN 0.5 ml outside the scope of a clinical trial); * Have a negative pregnancy test result at the first medical examination (if female and capable of bearing children); * Agree to employ adequate birth control measures for the duration of the study (if female and capable of bearing children); * Agree to keep a Subject Diary. Exclusion Criteria: Subjects will be excluded from participation in this study if they: * Have a history of any previous tick-borne encephalitis (TBE) vaccination; * Have a history of TBE infection; * Have a history of infection with or vaccination against other flaviviruses (e.g. dengue fever, yellow fever, Japanese B-encephalitis); * Have a history of allergic reactions, in particular to one of the components of the vaccine; * Suffer from a disease (e.g. autoimmune disease) or are undergoing a form of treatment (e.g. systemic corticosteroids) that can be expected to influence immunological functions; * Have a known or suspected problem with drug or alcohol abuse (\> 4 liters wine / week or equivalent level of other alcoholic beverages); * Have donated blood or plasma within 30 days of study entry; * Have received a blood transfusion or immunoglobulins within 30 days of study entry; * Are known to be HIV positive (an HIV test is not required specifically for the purpose of this study); * Are simultaneously participating in another clinical trial including administration of an investigational product; * Have participated in any other clinical study within six weeks prior to study entry; * Are pregnant or breastfeeding (if female); * Are a member of the team conducting this study or are in a dependent relationship with the study investigator. Dependent relationships include close relatives (i.e., children, partner/spouse, siblings, parents) as well as employees of the investigator. * Have received any other vaccination within two weeks prior to study entry.