title: Febrile Seizures After 2010-2011 Trivalent Inactivated Influenza Vaccine.
abstract: OBJECTIVE
  In the Post-Licensure Rapid Immunization Safety Monitoring Program, we examined risk of febrile seizures (FS) after trivalent inactivated influenza vaccine (TIV) and 13-valent pneumococcal conjugate vaccine (PCV13) during the 2010-2011 influenza season, adjusted for concomitant diphtheria tetanus acellular pertussis-containing vaccines (DTaP). Assuming children would receive both vaccines, we examined whether same-day TIV and PCV13 vaccination was associated with greater FS risk when compared with separate-day vaccination.
  
  
  METHODS
  We used a self-controlled risk interval design, comparing the FS rate in a risk interval (0-1 days) versus control interval (14-20 days). Vaccinations were identified in claims and immunization registry data. FS were confirmed with medical records.
  
  
  RESULTS
  No statistically significant TIV-FS associations were found in unadjusted or adjusted models (incidence rate ratio [IRR] adjusted for age, seasonality, and concomitant PCV13 and DTaP: 1.36, 95% confidence interval [CI] 0.78 to 2.39). Adjusted for age and seasonality, PCV13 was significantly associated with FS (IRR 1.74, 95% CI 1.06 to 2.86), but not when further adjusting for concomitant TIV and DTaP (IRR 1.61, 95% CI 0.91 to 2.82). Same-day TIV and PCV13 vaccination was not associated with excess risk of FS when compared with separate-day vaccination (1.08 fewer FS per 100 000 with same day administration, 95% CI -5.68 to 6.09).
  
  
  CONCLUSIONS
  No statistically significant increased risk of FS was found for 2010-2011 TIV or PCV13, when adjusting for concomitant vaccines. Same-day TIV and PCV13 vaccination was not associated with more FS compared with separate-day vaccination.
authors.affiliation: Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, Massachusetts; Alison_Kawai@harvardpilgrim.org.
authors.forename: Alison Tse
authors.initials: AT
authors.lastname: Kawai
authors.affiliation: US Food and Drug Administration Center for Biologics Evaluation and Research, Silver Spring, Maryland;
authors.forename: David
authors.initials: D
authors.lastname: Martin
authors.affiliation: Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, Massachusetts;
authors.forename: Martin
authors.initials: M
authors.lastname: Kulldorff
authors.affiliation: Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, Massachusetts;
authors.forename: Lingling
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, Massachusetts;
authors.forename: David V
authors.initials: DV
authors.lastname: Cole
authors.affiliation: Aetna, Blue Bell, Pennsylvania;
authors.forename: Cheryl N
authors.initials: CN
authors.lastname: McMahill-Walraven
authors.affiliation: HealthCore, Wilmington, Delaware;
authors.forename: Nandini
authors.initials: N
authors.lastname: Selvam
authors.affiliation: Comprehensive Health Insights, Humana Inc, Louisville, Kentucky; and.
authors.forename: Mano S
authors.initials: MS
authors.lastname: Selvan
authors.affiliation: Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, Massachusetts; Division of Infectious Diseases, Boston Children's Hospital, Boston, Massachusetts.
authors.forename: Grace M
authors.initials: GM
authors.lastname: Lee
mesh_terms: D002648:Child; D002675:Child, Preschool; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007223:Infant; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000009:adverse effects*; D008297:Male; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000009:adverse effects*; D012307:Risk Factors; D003294:Seizures, Febrile / Q000139:chemically induced* / Q000453:epidemiology; D018074:Vaccines, Conjugate
chemical_list: C538862:13-valent pneumococcal vaccine; D015721:Diphtheria-Tetanus-Pertussis Vaccine; D007252:Influenza Vaccines; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate