title: Guillain-Barre syndrome during the 2009-2010 H1N1 influenza vaccination campaign: population-based surveillance among 45 million Americans.
abstract: Because of widespread distribution of the influenza A (H1N1) 2009 monovalent vaccine (pH1N1 vaccine) and the prior association between Guillain-Barré syndrome (GBS) and the 1976 H1N1 influenza vaccine, enhanced surveillance was implemented to estimate the magnitude of any increased GBS risk following administration of pH1N1 vaccine. The authors conducted active, population-based surveillance for incident cases of GBS among 45 million persons residing at 10 Emerging Infections Program sites during October 2009-May 2010; GBS was defined according to published criteria. The authors determined medical and vaccine history for GBS cases through medical record review and patient interviews. The authors used vaccine coverage data to estimate person-time exposed and unexposed to pH1N1 vaccine and calculated age- and sex-adjusted rate ratios comparing GBS incidence in these groups, as well as age- and sex-adjusted numbers of excess GBS cases. The authors received 411 reports of confirmed or probable GBS. The rate of GBS immediately following pH1N1 vaccination was 57% higher than in person-time unexposed to vaccine (adjusted rate ratio = 1.57, 95% confidence interval: 1.02, 2.21), corresponding to 0.74 excess GBS cases per million pH1N1 vaccine doses (95% confidence interval: 0.04, 1.56). This excess risk was much smaller than that observed during the 1976 vaccine campaign and was comparable to some previous seasonal influenza vaccine risk assessments.
authors.affiliation: Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. cxx4@cdc.gov
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Wise
authors.forename: Melissa
authors.initials: M
authors.lastname: Viray
authors.forename: James J
authors.initials: JJ
authors.lastname: Sejvar
authors.forename: Paige
authors.initials: P
authors.lastname: Lewis
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Baughman
authors.forename: Walter
authors.initials: W
authors.lastname: Connor
authors.forename: Richard
authors.initials: R
authors.lastname: Danila
authors.forename: Greg P
authors.initials: GP
authors.lastname: Giambrone
authors.forename: Christa
authors.initials: C
authors.lastname: Hale
authors.forename: Brenna C
authors.initials: BC
authors.lastname: Hogan
authors.forename: James I
authors.initials: JI
authors.lastname: Meek
authors.forename: Rendi
authors.initials: R
authors.lastname: Murphree
authors.forename: John Y
authors.initials: JY
authors.lastname: Oh
authors.forename: Arthur
authors.initials: A
authors.lastname: Reingold
authors.forename: Norisse
authors.initials: N
authors.lastname: Tellman
authors.forename: Susan M
authors.initials: SM
authors.lastname: Conner
authors.forename: James A
authors.initials: JA
authors.lastname: Singleton
authors.forename: Peng-Jun
authors.initials: PJ
authors.lastname: Lu
authors.forename: Frank
authors.initials: F
authors.lastname: DeStefano
authors.forename: Scott K
authors.initials: SK
authors.lastname: Fridkin
authors.forename: Claudia
authors.initials: C
authors.lastname: Vellozzi
authors.forename: Oliver W
authors.initials: OW
authors.lastname: Morgan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D020275:Guillain-Barre Syndrome / Q000453:epidemiology / Q000209:etiology*; D006293:Health Promotion; D006801:Humans; D015994:Incidence; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000009:adverse effects*; D007251:Influenza, Human / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D011358:Product Surveillance, Postmarketing; D018570:Risk Assessment; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines