- Trial to assess asthma exacerbation through to the end of the study; and to demonstrate that the efficacy over one season against culture-confirmed influenza-illness; and finally to assess the safety and tolerability of CAIV-T in children with asthma.

- To assess asthma exacerbation, being defined as acute wheezing illness associated with hospitalization, unscheduled clinic visits, or new prescriptions from study vaccination through to the end of the study.

Inclusion Criteria:

• who are aged at least 6 years to 17 years of age at the time of enrollment;
• with a clinical diagnosis of asthma by one of the following criteria:
• An International Classification of Diseases, Ninth revision (ICD-9) code 493 AND ≥one prescription for asthma medication;
• OR ≥one prescription for an inhaled beta-agonist and ≥one prescription for cromolyn;
• OR ≥Five prescriptions for any asthma medication (adapted from Kramarz et al,2000 and Osborne et al., 1995)1,2;
• asthma medication* is being defined as:
• inhaled and oral β -agonists
• theophyllin
• inhaled, oral and injected steroids
• other unclassified asthma medication
• antibiotics used for treatment of respiratory illness associated with a wheezing episode;
• at least one asthma medication should have been administered in the last 12 months
• who, if female and is post-menarche, has provided a negative pregnancy test prior to the study vaccination;
• who have provided written informed consent (as appropriate and according to national guidelines) and 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;
• who/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/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 of a dose equivalent to a total of 20 mg/day or greater of prednisolone or equivalent, for more than 14 days duration until 2 weeks after corticosteroids have been discontinued 25;
• 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;
• who have an immunosuppressed or an immunocompromised individual living in the same household;
• who received any influenza vaccine in the 6 months prior to enrollment, or are anticipated to receive a non-study influenza vaccine after enrollment;
• with a documented history of hypersensitivity to egg or egg protein or any other component of the CAIV-T or TIV;
• 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;
• 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 subject is not a contraindication to the enrollment or ongoing participation of the subject in the study.