title: Guillain-Barré syndrome and preceding infection with campylobacter, influenza and Epstein-Barr virus in the general practice research database.
abstract: BACKGROUND
  A number of infectious agents have previously been suggested as risk factors for the development of Guillain-Barré syndrome (GBS), but robust epidemiologic evidence for these associations is lacking.
  
  
  RESULTS
  We conducted a nested case-control study using data from the United Kingdom General Practice Research Database between 1991 and 2001. Controls were matched to cases on general practice clinic, sex, year of birth and date of outcome diagnosis in their matched case. We found positive associations between GBS and infection with Campylobacter, Epstein-Barr virus and influenza-like illness in the previous two months, as well as evidence of a protective effect of influenza vaccination. After correction for under-ascertainment of Campylobacter infection, the excess risk of GBS following Campylobacter enteritis was 60-fold and 20% of GBS cases were attributable to this pathogen.
  
  
  CONCLUSIONS
  Our findings indicate a far greater excess risk of GBS among Campylobacter enteritis patients than previously reported by retrospective serological studies. In addition, they confirm previously suggested associations between infection due to Epstein-Barr virus infection and influenza-like illness and GBS. Finally, we report evidence of a protective effect of influenza vaccination on GBS risk, which may be mediated through protection against influenza disease, or result from a lower likelihood of vaccination among those with recent infection. Cohort studies of GBS incidence in this population would help to clarify the burden of GBS due to influenza, and any potential protective effect of influenza vaccination.
authors.affiliation: Infectious Disease Epidemiology Unit, Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom. clarence.tam@lshtm.ac.uk
authors.forename: Clarence C
authors.initials: CC
authors.lastname: Tam
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: O'Brien
authors.forename: Irene
authors.initials: I
authors.lastname: Petersen
authors.forename: Amir
authors.initials: A
authors.lastname: Islam
authors.forename: Andrew
authors.initials: A
authors.lastname: Hayward
authors.forename: Laura C
authors.initials: LC
authors.lastname: Rodrigues
mesh_terms: D002169:Campylobacter Infections / Q000150:complications*; D016022:Case-Control Studies; D003628:Database Management Systems; D020031:Epstein-Barr Virus Infections / Q000150:complications*; D020275:Guillain-Barre Syndrome / Q000209:etiology* / Q000382:microbiology / Q000821:virology; D006801:Humans; D007252:Influenza Vaccines / Q000008:administration & dosage; D007251:Influenza, Human / Q000150:complications* / Q000517:prevention & control
chemical_list: D007252:Influenza Vaccines