A Post Marking Study to Evaluate the Safety of FluMist in Children

A Post Marketing Evaluation of the Safety of FluMist in Children 24-59 Months of Age in a Managed Care Setting

To assess the safety of FluMist vaccination

• To assess the safety of FluMist vaccination Rates of medically attended events in FluMist recipients, including serious adverse events (SAEs), anaphylaxis , urticaria, asthma, wheezing, pre-specified grouped diagnoses, and rare events potentially related to wild-type influenza, will be compared to rates in multiple non-randomized control groups.
• To assess the safety of annual FluMist re-vaccination [Rates of MAEs in the subset of children who receive FluMist in ≥2 consecutive years will be compared to rates in first-time vaccinees during the same season.]
• To assess the safety of FluMist vaccination in children previously vaccinated with trivalent inactivated influenza vaccine (TIV) [Rates of MAEs in the subset of children who received one or more prior TIV vaccinations will be compared to rates in children who did not receive prior TIV.]

Inclusion Criteria:

• Healthy
• Age: born within the same calendar quarter as the reference FluMist vaccinee.

Exclusion Criteria:

• Children who have evidence of medical conditions that put them at high risk for complications of influenza (e.g., chronic cardiovascular and pulmonary disease) will be excluded from this control group.