title: Measles humoral and cell-mediated immunity in children aged 5-10 years after primary measles immunization administered at 6 or 9 months of age.
abstract: BACKGROUND
  Given the high infant measles mortality rate, there is interest in whether a measles immunization regimen beginning at <12 months of age provides lasting immunity.
  
  
  METHODS
  Measles-specific immune responses were evaluated in 70 children aged 5-10 years after primary measles vaccine administered at 6, 9, or 12 months.
  
  
  RESULTS
  At 5-10 years of age, the stimulation index for measles T-cell proliferation was 11.4 (SE, 1.3), 10.9 (SE, 1.5), and 14.4 (SE 2.1) when the first measles dose was given at 6, 9, or 12 months, respectively. Neutralizing antibody concentration (geometric mean titer [GMT]) in those immunized at 6 months of age was 125 mIU/mL (95% confidence interval [CI], 42-377) in the presence of passive antibodies (PAs) and 335 mIU/mL (95% CI, 211-531) in those without PAs; in those immunized at 9 months, GMTs were 186 mIU/mL (95% CI, 103-335) and 1080 mIU/mL (95% CI, 642-1827) in the presence and absence of PAs, respectively. The GMT was 707 mIU/mL (95% CI, 456-1095) when vaccine was administered at 12 months (P ≤ .04).
  
  
  CONCLUSIONS
  Measles-specific T-cell responses were sustained at 5-10 years of age regardless of age at time of primary measles immunization. Neutralizing antibody concentrations were lower in cohorts given the first vaccine dose at 6 months of age and in the presence of PAs; however, responses could be boosted by subsequent doses. Starting measles vaccination at <12 months of age may be beneficial during measles outbreaks or in endemic areas.
authors.affiliation: Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 94305-5208, USA.
authors.forename: Hayley A
authors.initials: HA
authors.lastname: Gans
authors.forename: Linda L
authors.initials: LL
authors.lastname: Yasukawa
authors.forename: Phillip
authors.initials: P
authors.lastname: Sung
authors.forename: Barbara
authors.initials: B
authors.lastname: Sullivan
authors.forename: Ross
authors.initials: R
authors.lastname: DeHovitz
authors.forename: Susette
authors.initials: S
authors.lastname: Audet
authors.forename: Judy
authors.initials: J
authors.lastname: Beeler
authors.forename: Ann M
authors.initials: AM
authors.lastname: Arvin
mesh_terms: D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D007115:Immunization Schedule; D008213:Lymphocyte Activation; D008297:Male; D008457:Measles / Q000276:immunology* / Q000517:prevention & control; D008458:Measles Vaccine / Q000008:administration & dosage* / Q000276:immunology*; D008459:Measles virus / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014611:Vaccination
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D008458:Measles Vaccine