title: The immunogenicity and impact on nasopharyngeal carriage of fewer doses of conjugate pneumococcal vaccine immunization schedule.
abstract: The immunogenicity and impact on carriage of fewer doses of pneumococcal conjugate vaccine (PCV7) followed by booster with pneumococcal polysaccharide vaccine (PPV) were investigated. 684 infants were assigned randomly to one of the three groups that received one (A), two (B) or three (C) doses of PCV7 between 2 and 4 months of age, plus PPV at 10 months. Following primary vaccination protective antibody titers of >0.35 μg/ml against the PCV7 serotypes combined increased significantly with the number of PCV7 doses, 44% vs. 77% vs. 94% (p<0.001), and correlated positively with the opsonophagocytic indices, but negatively with nasopharyngeal carriage of pneumococcus. The differences in antibody responses and pneumococcal carriage between the groups diminished following booster with PPV, implying that administration of one or two doses of PCV7, with a booster dose of PPV might lower the cost of protection against IPD in young children in resource poor countries.
authors.affiliation: Medical Research Council Laboratories, Banjul, Gambia. mota@mrc.gm
authors.forename: Martin O
authors.initials: MO
authors.lastname: Ota
authors.forename: Adebayo
authors.initials: A
authors.lastname: Akinsola
authors.forename: John
authors.initials: J
authors.lastname: Townend
authors.forename: Martin
authors.initials: M
authors.lastname: Antonio
authors.forename: Godwin
authors.initials: G
authors.lastname: Enwere
authors.forename: David
authors.initials: D
authors.lastname: Nsekpong
authors.forename: Abdoulie
authors.initials: A
authors.lastname: Bojang
authors.forename: Mark
authors.initials: M
authors.lastname: Saaka
authors.forename: R L
authors.initials: RL
authors.lastname: Burton
authors.forename: Akram
authors.initials: A
authors.lastname: Zaman
authors.forename: David
authors.initials: D
authors.lastname: Goldblatt
authors.forename: Richard A
authors.initials: RA
authors.lastname: Adegbola
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood; D000917:Antibody Formation; D005260:Female; D005714:Gambia; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007115:Immunization Schedule; D007117:Immunization, Secondary; D007223:Infant; D008297:Male; D009305:Nasopharynx / Q000382:microbiology*; D011008:Pneumococcal Infections / Q000276:immunology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000008:administration & dosage*; D018074:Vaccines, Conjugate / Q000008:administration & dosage
chemical_list: D000907:Antibodies, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate