title: A postmarketing evaluation of the safety of Ann Arbor strain live attenuated influenza vaccine in children 5 through 17 years of age.
abstract: BACKGROUND
  Live attenuated influenza vaccine (LAIV) was licensed in 2003 in the United States for use in individuals aged 5-49 years.
  
  
  METHODS
  A prospective observational postmarketing study was conducted to evaluate the safety of LAIV. Rates of medically attended events (MAEs) and serious adverse events (SAEs) in eligible children aged 5-17 years receiving LAIV as part of routine care from October 2003 to March 2008 were compared with rates in nonrandomized self, matched unvaccinated, and matched trivalent inactivated influenza vaccine (TIV)-vaccinated controls. All MAEs and SAEs through 42 days postvaccination and all hospitalizations and deaths through 6 months postvaccination were analyzed. Statistical significance was assigned without multiplicity adjustment.
  
  
  RESULTS
  43,702 LAIV recipients were matched with similar numbers of TIV-vaccinated and unvaccinated children. Of approximately 9500 MAE incidence rate comparisons, 204 were statistically significantly higher and 168 were statistically significantly lower in LAIV recipients versus controls. No pattern of MAE rate differences suggested a safety signal with LAIV. Asthma/wheezing MAEs were not statistically increased in LAIV recipients. No anaphylaxis events occurred within 3 days postvaccination. Rates of SAEs were similar between LAIV and control groups. Two SAEs were considered possibly related to LAIV: Bell's palsy and nonspecific paroxysmal spell.
  
  
  CONCLUSIONS
  Results of this postlicensure evaluation of LAIV safety in US children aged 5-17 years are consistent with preapproval clinical studies and Vaccine Adverse Event Reporting System reports, both of which demonstrated no significant increase in asthma/wheezing events or other adverse outcomes among eligible children who received LAIV.
authors.affiliation: Kaiser Permanente Vaccine Study Center, Oakland, CA 94612, USA. roger.baxter@kp.org
authors.forename: Roger
authors.initials: R
authors.lastname: Baxter
authors.forename: Seth L
authors.initials: SL
authors.lastname: Toback
authors.forename: Frangiscos
authors.initials: F
authors.lastname: Sifakis
authors.forename: John
authors.initials: J
authors.lastname: Hansen
authors.forename: Joan
authors.initials: J
authors.lastname: Bartlett
authors.forename: Laurie
authors.initials: L
authors.lastname: Aukes
authors.forename: Ned
authors.initials: N
authors.lastname: Lewis
authors.forename: Xionghua
authors.initials: X
authors.lastname: Wu
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Ambrose
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D064420:Drug-Related Side Effects and Adverse Reactions / Q000453:epidemiology*; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000009:adverse effects*; D008297:Male; D011358:Product Surveillance, Postmarketing; D011446:Prospective Studies; D016019:Survival Analysis; D014481:United States; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000009:adverse effects
chemical_list: D007252:Influenza Vaccines; D014613:Vaccines, Attenuated