title: Serologic responses to an Haemophilus influenzae type b polysaccharide-Neisseria meningitidis outer membrane protein conjugate vaccine in very young Gambian infants.
abstract: Recent studies in the United States and Europe have shown that Haemophilus influenzae type b polysaccharide-protein conjugate vaccines can induce protective antibody levels in young infants, but it was not clear that this would be the case in African infants, to whom H influenzae vaccines must be given at a very early age to prevent disease caused by H influenzae. Therefore, antibody responses to an H influenzae type b polysaccharide-Neisseria meningitidis outer membrane protein conjugate vaccine were measured in very young Gambian infants. In the first group (n = 85), to whom the vaccine was given at the ages of 1 and 3 months, the geometric mean antibody level rose from a prevaccination level of 0.23 microgram/mL to a postvaccination level of 1.27 micrograms/mL, and in the second group (n = 56), vaccinated at the ages of 2 and 4 months, the prevaccination level of 0.16 microgram/mL rose to a postvaccination level of 1.59 micrograms/mL. These two final postvaccination levels did not differ significantly, and interpolation suggests that similar antibody levels were present in both groups of infants at the age of 3 months. This is the age by which protection would need to be achieved to protect against H influenzae meningitis in The Gambia and in other countries where the infection has similar epidemiologic characteristics. No significant side effects of vaccination were noted.
authors.affiliation: Medical Research Council Laboratories, Fajara, Banjul, The Gambia, West Africa.
authors.forename: H
authors.initials: H
authors.lastname: Campbell
authors.forename: P
authors.initials: P
authors.lastname: Byass
authors.forename: V I
authors.initials: VI
authors.lastname: Ahonkhai
authors.forename: P P
authors.initials: PP
authors.lastname: Vella
authors.forename: B M
authors.initials: BM
authors.lastname: Greenwood
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D001425:Bacterial Outer Membrane Proteins / Q000009:adverse effects / Q000276:immunology*; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D004341:Drug Evaluation; D005714:Gambia; D006193:Haemophilus influenzae / Q000276:immunology*; D006801:Humans; D007115:Immunization Schedule; D007223:Infant; D009345:Neisseria meningitidis / Q000276:immunology*; D011135:Polysaccharides, Bacterial / Q000009:adverse effects / Q000276:immunology*; D011863:Radioimmunoassay; D012424:Rural Population; D013997:Time Factors
chemical_list: D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D011135:Polysaccharides, Bacterial