title: The effect of chronic cytomegalovirus infection on pneumococcal vaccine responses.
abstract: BACKGROUND
  Immune function declines with age and has been associated with reduced vaccine responsiveness. Chronic infection with cytomegalovirus (CMV) has been proposed as a contributor to poorer responses in older adults. A pneumococcal vaccine has been recommended in the United Kingdom for those aged >65 years since 2003 to prevent pneumococcal disease.
  
  
  METHODS
  We evaluated the effect of age and CMV status on pneumococcal vaccine responses in 348 individuals aged 50-70 years.
  
  
  RESULTS
  We found participant age to be associated with serotype-specific and functional antibody titers after pneumococcal vaccination, with a mean 6.2% (95% confidence interval, 2.9%-9.5%) reduction in postvaccination functional antibody titers per year. CMV status was not associated with serotype-specific immunoglobulin G concentrations or functional antibody titers after pneumococcal vaccination. However, CMV seropositivity was associated with higher levels of prevaccination functional antibody for 4 of 7 pneumococcal serotypes assessed.
  
  
  CONCLUSIONS
  These data imply that CMV infection is not directly responsible for the decline in pneumococcal vaccine responses seen with age but suggest that CMV-seropositive individuals differ in their natural exposure to pneumococci or have altered mucosal immune responses after colonization with this organism.
authors.affiliation: Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre.
authors.forename: Daniel
authors.initials: D
authors.lastname: O'Connor
authors.forename: Johannes
authors.initials: J
authors.lastname: Trück
authors.forename: Rajeka
authors.initials: R
authors.lastname: Lazarus
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Clutterbuck
authors.forename: Merryn
authors.initials: M
authors.lastname: Voysey
authors.forename: Katie
authors.initials: K
authors.lastname: Jeffery
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Pollard
mesh_terms: D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood; D002908:Chronic Disease; D003586:Cytomegalovirus Infections / Q000276:immunology* / Q000473:pathology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D022242:Pneumococcal Vaccines / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines