title: Safety and immunogenicity of a conjugated Haemophilus influenzae type B polysaccharide-Neisseria meningitidis outer membrane protein vaccine.
abstract: This study was performed to determine the immunogenicity and safety of a conjugate Haemophilus influenzae type b (Hib) vaccine (PedvaxHIB:Merck Sharp & Dohme Inc, West Point, PA, USA) in Taiwanese children. There were two groups in this study. Group A included 56 infants at 2 months of age, who received an initial dose of Hib conjugate vaccine at age 2 months and 4 months. Another booster dose was given between 12 and 15 months of age. Group B included 58 children, aged 11 to 14 months, who were vaccinated at the time of enrollment and 2 months after the first vaccination. The results showed that this Hib conjugate vaccine was highly immunogenic with 100% and 86% of vaccinees in group A developing anti-Hib polyribosylribitol phosphate (PRP) antibody titers above 0.15 microgram/mL and 1 microgram/mL, respectively, after two vaccinations. A slightly better response rate was observed in group B, with 100% and 97% of vaccinees developing antibody titers above 0.15 microgram/mL and 1 microgram/ml, respectively, after two vaccinations. A significant booster effect was seen in group A; the proportion of subjects with antibody titers above 1 microgram/mL increased from 38% to 95%, and the geometric mean titer increased from 0.68 microgram/mL to 11.92 micrograms/mL. Adverse reactions were uncommon. Mild reactions consisted of low-grade fever and local discomfort. We conclude that the Hib conjugate vaccine is highly immunogenic and safe when given to Taiwanese children as young as 2 months of age.
authors.affiliation: Department of Pediatrics, College of Medicine, National Taiwan University Hospital, Taipei, ROC.
authors.forename: S J
authors.initials: SJ
authors.lastname: Yeh
authors.forename: L M
authors.initials: LM
authors.lastname: Huang
authors.forename: J M
authors.initials: JM
authors.lastname: Chen
authors.forename: P I
authors.initials: PI
authors.lastname: Lee
authors.forename: L Y
authors.initials: LY
authors.lastname: Chang
authors.forename: Y J
authors.initials: YJ
authors.lastname: Lin
authors.forename: H H
authors.initials: HH
authors.lastname: Chiu
authors.forename: C Y
authors.initials: CY
authors.lastname: Lee
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood; D001425:Bacterial Outer Membrane Proteins / Q000009:adverse effects / Q000276:immunology*; D005260:Female; D018073:Haemophilus Vaccines / Q000009:adverse effects / Q000276:immunology*; D006801:Humans; D007114:Immunization; D007223:Infant; D008297:Male; D011135:Polysaccharides, Bacterial / Q000009:adverse effects / Q000276:immunology*; D018074:Vaccines, Conjugate / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D018073:Haemophilus Vaccines; C061964:Haemophilus influenzae-type b polysaccharide-Neisseria meningitidis outer membrane protein conjugate vaccine; D011135:Polysaccharides, Bacterial; D018074:Vaccines, Conjugate