Trial to Determine the Safety and Efficacy of Influenza Virus Vaccine, Trivalent, Types A & B, Live Cold- Adapted (CAIV-T) in Healthy Children Attending Day Care Centers

A Prospective, Randomized, Double-Blind, Placebo-Controlled, Trial to Determine the Safety and Efficacy of Influenza Virus Vaccine, Trivalent, Types A & B, Live Cold-Adapted (CAIV-T) in Healthy Children Attending Day Care Centers

The purpose of this study is to determine the efficacy of the liquid formulation of CAIVT against culture confirmed influenza illness in healthy children aged at least 6 months and less than 36 months, attending day care centers in Europe. In addition, the trial provides the opportunity to investigate the effect of CAIV-T on acute otitis media, on healthcare resource utilization and economic resources.

Inclusion Criteria:

• who are aged at least 6 months and less than 36 months of age at the time of enrollment, attending day care for at least three days a week, four hours a day;
• who are in good health as determined by medical history, physical examination and clinical judgement;
• whose parent(s)/legal guardian(s) have provided written informed consent after the nature of the study has been explained;
• who, along with their parent(s)/legal guardian(s), will be available for duration of the trial (8 months ± 1 month);
• whose parent(s)/legal guardian(s), can be reached by study staff for the post-vaccination contacts [telephone, clinic or home visit].

Exclusion Criteria:

• whose parent(s)/legal guardian(s) are perceived to be unavailable or difficult to contact for evaluation or study visits during the study period;
• with any serious chronic disease (e.g., with signs of cardiac or renal failure or severe malnutrition), including progressive neurological disease;
• with Down's syndrome or other known cytogenetic disorders;
• with a known or suspected disease of the immune system or those receiving immunosuppressive therapy, including systemic corticosteroids; who received any blood products, including immunoglobulin, in the period from six months prior to vaccination through to the conclusion of the study;
• for whom there is intent to administer any other investigational vaccine or agent from one month prior to enrollment through to the conclusion of the study;
• have an immunosuppressed or an immunocompromised individual living in the same household; who, at any time prior to entry into this study, received a dose of any influenza vaccine (commercial or investigational);
• who, in the two weeks prior to entry into this study, received a dose of any influenza treatment (commercial or investigational);
• with a documented history of hypersensitivity to egg or egg protein or any other component of the study vaccine or placebo;
• with a clinically confirmed respiratory illness with wheezing within two weeks prior to enrollment;
• who received aspirin (acetylsalicylic acid) or aspirin-containing products in the two weeks prior to enrollment or for which use is anticipated during the study;
• who were administered any live virus vaccine within one month prior to enrollment or expected to receive another live virus vaccine within one month of vaccination in this study;
• with any medical conditions that in the opinion of the investigator might interfere with interpretation of the study results; If any of these criteria are met following enrolment, the subject will be excluded from subsequent vaccine dosing.

Note: A pregnant household member is not considered a contraindication to enrollment.