Risk of Guillain-Barré syndrome following pandemic influenza A(H1N1) 2009 vaccination in Germany

Pharmacoepidemiol Drug Saf. 2014 Nov;23(11):1192-204. doi: 10.1002/pds.3638. Epub 2014 May 10.


Purpose: A prospective, epidemiologic study was conducted to assess whether the 2009 pandemic influenza A(H1N1) vaccination in Germany almost exclusively using an AS03-adjuvanted vaccine (Pandemrix) impacts the risk of Guillain-Barré syndrome (GBS) and its variant Fisher syndrome (FS).

Methods: Potential cases of GBS/FS were reported by 351 participating hospitals throughout Germany. The self-controlled case series methodology was applied to all GBS/FS cases fulfilling the Brighton Collaboration (BC) case definition (levels 1-3 of diagnostic certainty) with symptom onset between 1 November 2009 and 30 September 2010 reported until end of December 2010.

Results: Out of 676 GBS/FS reports, in 30 cases, GBS/FS (BC levels 1-3) occurred within 150 days following influenza A(H1N1) vaccination. The relative incidence of GBS/FS within the primary risk period (days 5-42 post-vaccination) compared with the control period (days 43-150 post-vaccination) was 4.65 (95%CI [2.17, 9.98]). Similar results were found when stratifying for infections within 3 weeks prior to onset of GBS/FS and when excluding cases with additional seasonal influenza vaccination. The overall result of temporally adjusted analyses supported the primary finding of an increased relative incidence of GBS/FS following influenza A(H1N1) vaccination.

Conclusions: The results indicate an increased risk of GBS/FS in temporal association with pandemic influenza A(H1N1) vaccination in Germany.

Keywords: Guillain-Barré syndrome; pandemic influenza vaccination; pharmacoepidemiology; self-controlled case series.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Child
  • Child, Preschool
  • Comorbidity
  • Confounding Factors, Epidemiologic
  • Epidemiologic Studies
  • Female
  • Germany / epidemiology
  • Guillain-Barre Syndrome / chemically induced*
  • Humans
  • Incidence
  • Influenza A Virus, H1N1 Subtype*
  • Influenza Vaccines / adverse effects*
  • Influenza, Human / prevention & control*
  • Male
  • Middle Aged
  • Miller Fisher Syndrome / etiology
  • Prospective Studies
  • Sex Factors
  • Time Factors


  • Influenza Vaccines
  • pandemrix