A Case Control Study of the Effectiveness of Q/LAIV Versus Inactivated Influenza Vaccine and No Vaccine in Subjects 2-17 Years of Age

Inclusion Criteria: * Community-dwelling children and adolescents 2 to 17 years of age. * Written Informed Consent or Assent. * Acute respiratory illness documented at study visit or at home with fever (oral temperature ≥ 100.0° Fahrenheit at study visit, or history of fever reported by parents, or use of antipyretic prior to study visit) * Symptom onset less than 5 days prior to study visit. * Subject and/or subject's legal representative is able to understand and comply with the requirements of the protocol as judged by the investigator. Exclusion Criteria: * Treatment with an antiviral drug for influenza (oseltamivir or Tamiflu®, zanamivir or Relenza®) during the 14 days before enrollment * Any condition that, in the opinion of the investigator, would interfere with interpretation of subject safety or study results * Concurrent enrollment in another clinical study Patient already enrolled during this influenza season * Employees of the clinical study site or any other individuals involved with the conduct of the study, or immediate family members of such individuals.