title: Association of infectious mononucleosis with multiple sclerosis. A population-based study.
abstract: BACKGROUND
  Genetic and environmental factors have important roles in multiple sclerosis (MS) susceptibility. Several studies have attempted to correlate exposure to viral illness with the subsequent development of MS. Here in a population-based Canadian cohort, we investigate the relationship between prior clinical infection or vaccination and the risk of MS.
  
  
  METHODS
  Using the longitudinal Canadian database, 14,362 MS index cases and 7,671 spouse controls were asked about history of measles, mumps, rubella, varicella and infectious mononucleosis as well as details about vaccination with measles, mumps, rubella, hepatitis B and influenza vaccines. Comparisons were made between cases and spouse controls.
  
  
  RESULTS
  Spouse controls and stratification by sex appear to correct for ascertainment bias because with a single exception we found no significant differences between cases and controls for all viral exposures and vaccinations. However, 699 cases and 165 controls reported a history of infectious mononucleosis (p < 0.001, corrected odds ratio 2.06, 95% confidence interval 1.71-2.48). Females were more aware of disease history than males (p < 0.001).
  
  
  CONCLUSIONS
  The data further confirms a reporting distortion between males and females. Historically reported measles, mumps, rubella, varicella and vaccination for hepatitis B, influenza, measles, mumps and rubella are not associated with increased risk of MS later in life. A clinical history of infectious mononucleosis is conspicuously associated with increased MS susceptibility. These findings support studies implicating Epstein-Barr virus in MS disease susceptibility, but a co-association between MS susceptibility and clinically apparent infectious mononucleosis cannot be excluded.
authors.affiliation: Wellcome Trust Centre for Human Genetics, Oxford, UK.
authors.forename: Sreeram V
authors.initials: SV
authors.lastname: Ramagopalan
authors.forename: William
authors.initials: W
authors.lastname: Valdar
authors.forename: David A
authors.initials: DA
authors.lastname: Dyment
authors.forename: Gabriele C
authors.initials: GC
authors.lastname: DeLuca
authors.forename: Irene M
authors.initials: IM
authors.lastname: Yee
authors.forename: Gavin
authors.initials: G
authors.lastname: Giovannoni
authors.forename: George C
authors.initials: GC
authors.lastname: Ebers
authors.forename: A Dessa
authors.initials: AD
authors.lastname: Sadovnick
mesh_terms: D002170:Canada / Q000453:epidemiology; D016022:Case-Control Studies; D002644:Chickenpox / Q000453:epidemiology / Q000517:prevention & control; D019433:Chickenpox Vaccine / Q000008:administration & dosage; D015331:Cohort Studies; D004198:Disease Susceptibility; D005260:Female; D017325:Hepatitis B Vaccines / Q000008:administration & dosage; D006801:Humans; D007244:Infectious Mononucleosis / Q000453:epidemiology*; D007252:Influenza Vaccines / Q000008:administration & dosage; D008297:Male; D008457:Measles / Q000453:epidemiology / Q000517:prevention & control; D008458:Measles Vaccine / Q000008:administration & dosage; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000453:epidemiology* / Q000209:etiology; D009107:Mumps / Q000453:epidemiology / Q000517:prevention & control; D009108:Mumps Vaccine / Q000008:administration & dosage; D012307:Risk Factors; D012409:Rubella / Q000453:epidemiology / Q000517:prevention & control; D012411:Rubella Vaccine / Q000008:administration & dosage; D012737:Sex Factors
chemical_list: D019433:Chickenpox Vaccine; D017325:Hepatitis B Vaccines; D007252:Influenza Vaccines; D008458:Measles Vaccine; D009108:Mumps Vaccine; D012411:Rubella Vaccine