A Phase II, Trial to Assess the Safety and Tolerability of Influenza Virus Vaccine, CAIV-T in Healthy Children and Adolescents Ages 6 to Less Than 18 Years.

Inclusion Criteria: * who are aged 6 to less than 18 years at the time of enrolment * who, if female and is of child bearing potential is using reliable method of hormonal and/or non-hormonal contraception (which includes cervical cap, diaphragm, condoms, with spermicide or IUD) during sexual intercourse throughout the entire study period; has provided a negative pregnancy test (with detection limit of less than or equal to 25mL/ml) no more than 24 hours prior to the study vaccine administration and agreed to avoid pregnancy during participation in the study. N.B.lactating females are excluded from the study. * 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 until completion of the study * whose parent(s)/legal guardian(s), can be reached by study staff for the post vaccination contacts(telephone, clinic or home visit) Exclusion Criteria: * who along with their 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; or cytotoxic agents * who received any blood products, including immunoglobulin, in the period from six months prior to vaccination through to the conclusion of the study * have an immunosuppressed or an immunocompromised individual living in the same household * with a documented history of hypersensitivity to egg or egg protein or any other components of CAIV-T or placebo * who have a history of Guillain-Barre Syndrome (GBS) * 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 * who, in the two weeks prior to entry into the study, received a dose of influenza treatment (commercial or investigational) * 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, at anytime prior to study enrollment, received any influenza vaccine (commercial or investigational) * with asthma requiring regular medical follow up or hospitalization during the preceding year * with any medical conditions that in the opinion of the investigator might interfere with interpretation of the study results * Note: Pregnancy in any person who has regular contact with the subjects is not a contraindication to enrollment or ongoing participation of the subject in the study.