title: Immunogenicity following the first and second doses of 7-valent pneumococcal conjugate vaccine in HIV-infected and -uninfected infants.
abstract: BACKGROUND
  The immunogenicity of pneumococcal conjugate vaccine (PCV) has not been evaluated in HIV-infected infants following the first and second PCV-doses. We studied antibody kinetics of serotypes included in 7-valent PCV in HIV-infected and HIV-uninfected infants prior to and following each of three PCV-doses.
  
  
  METHODS
  HIV-uninfected infants born to HIV-uninfected (HUU) and HIV-infected mothers (HEU); and perinatal HIV-infected children with CD(4+)<25% randomized to initiate antiretroviral treatment (ART) when clinically and/or immunologically indicated (ART-) or immediately (ART+) were enrolled. Vaccination occurred at approximately 7.4, 11.5 and 15.5 weeks of age. Serotype-specific antibody was measured by ELISA following each PCV-dose and opsonophagocytic activity (OPA) to three serotypes following the second and third doses.
  
  
  RESULTS
  Pre-vaccination, antibody geometric mean concentrations (GMCs) were higher in HUU compared to HIV-exposed groups for most serotypes. GMCs and proportion of infants with antibody ≥0.35 μg/ml were similar in HUU compared to other groups following the second PCV-dose. In all groups, GMCs were greater following the third compared to post-second dose; and a higher proportion within each group had antibody ≥0.35 μg/ml to 6B and 23F. OPA GMTs increased after the third compared to post-second dose for studied-serotypes; as did the proportion with OPA ≥8 to 23F.
  
  
  CONCLUSIONS
  A two-dose primary-series of PCV probably confers similar protection against invasive pneumococcal disease in HIV-infected compared to HUU children. The inferior response to serotypes 6B and 23F, and lower GMCs and OPA GMTs, following two compared to after three PCV-doses may have implications in the prevention of pneumococcal disease in high-burden countries.
authors.affiliation: National Institute for Communicable Diseases - Division of National Health Laboratory Service, Centre for Vaccines and Immunology, Sandringham, South Africa. madhis@rmpru.co.za
authors.forename: Shabir A
authors.initials: SA
authors.lastname: Madhi
authors.forename: Alane
authors.initials: A
authors.lastname: Izu
authors.forename: Avye
authors.initials: A
authors.lastname: Violari
authors.forename: Mark F
authors.initials: MF
authors.lastname: Cotton
authors.forename: Ravindre
authors.initials: R
authors.lastname: Panchia
authors.forename: Els
authors.initials: E
authors.lastname: Dobbels
authors.forename: Poonam
authors.initials: P
authors.lastname: Sewraj
authors.forename: Nadia
authors.initials: N
authors.lastname: van Niekerk
authors.forename: Patrick
authors.initials: P
authors.lastname: Jean-Philippe
authors.forename: Peter V
authors.initials: PV
authors.lastname: Adrian
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015658:HIV Infections / Q000276:immunology*; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007223:Infant; D008297:Male; D009895:Opsonin Proteins / Q000097:blood; D010587:Phagocytosis; D011008:Pneumococcal Infections / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000008:administration & dosage* / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D009895:Opsonin Proteins; D022242:Pneumococcal Vaccines