title: Surveillance for adverse events following receipt of pandemic 2009 H1N1 vaccine in the Post-Licensure Rapid Immunization Safety Monitoring (PRISM) System, 2009-2010.
abstract: The Post-Licensure Rapid Immunization Safety Monitoring (PRISM) system is a cohort-based active surveillance network initiated by the US Department of Health and Human Services to supplement preexisting and other vaccine safety monitoring systems in tracking the safety of monovalent pandemic 2009 H1N1 influenza vaccine in the United States during 2009-2010. PRISM investigators conducted retrospective analysis to determine whether 2009 H1N1 vaccination was associated with increased risk of any of 14 prespecified outcomes. Five health insurance and associated companies with 38 million members and 9 state/city immunization registries contributed records on more than 2.6 million doses of 2009 H1N1 vaccine. Data on outcomes came from insurance claims. Complementary designs (self-controlled risk interval, case-centered, and current-vs.-historical comparison) were used to optimize control for confounding and statistical power. The self-controlled risk interval analysis of chart-confirmed Guillain-Barré syndrome found an elevated but not statistically significant incidence rate ratio following receipt of inactivated 2009 H1N1 vaccine (incidence rate ratio = 2.50, 95% confidence interval: 0.42, 15.0) and no cases following live attenuated 2009 H1N1 vaccine. The study did not control for infection prior to Guillain-Barré syndrome, which may have been a confounder. The risks of other health outcomes of interest were generally not significantly elevated after 2009 H1N1 vaccination.
authors.affiliation: Department of Population Medicine, Harvard Medical School, Boston, Massachusetts 02215, USA. katherine_yih@harvardpilgrim.org
authors.forename: W Katherine
authors.initials: WK
authors.lastname: Yih
authors.forename: Grace M
authors.initials: GM
authors.lastname: Lee
authors.forename: Tracy A
authors.initials: TA
authors.lastname: Lieu
authors.forename: Robert
authors.initials: R
authors.lastname: Ball
authors.forename: Martin
authors.initials: M
authors.lastname: Kulldorff
authors.forename: Melisa
authors.initials: M
authors.lastname: Rett
authors.forename: Peter M
authors.initials: PM
authors.lastname: Wahl
authors.forename: Cheryl N
authors.initials: CN
authors.lastname: McMahill-Walraven
authors.forename: Richard
authors.initials: R
authors.lastname: Platt
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Salmon
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D015331:Cohort Studies; D005260:Female; D020275:Guillain-Barre Syndrome / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015994:Incidence; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000009:adverse effects*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D011358:Product Surveillance, Postmarketing; D012189:Retrospective Studies; D018570:Risk Assessment; D014481:United States / Q000453:epidemiology; D014483:United States Dept. of Health and Human Services; D014613:Vaccines, Attenuated / Q000009:adverse effects; D015164:Vaccines, Inactivated / Q000009:adverse effects; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines; D014613:Vaccines, Attenuated; D015164:Vaccines, Inactivated