Safety and immunogenicity of a new Haemophilus influenzae type b vaccine in infants under one year of age.
64 healthy infants 2-3 months old, were randomly assigned to one of three vaccination groups which received either diphtheria-pertussis-tetanus (DPT) vaccine, Haemophilus influenzae type b capsular polysaccharide polyribosyl-ribitol phosphate (PRP) vaccine, or PRP + P (with pertussis adjuvant) vaccine in three doses at intervals of 2 months. Local and systemic reactions occurred most frequently after DPT vaccination and least frequently for PRP alone. Data for 60 infants from whom complete sera sets were available indicated that 70% of the infants who received three doses of PRP + P showed 2-fold or greater increases in titres of antibody to PRP with final values above the level assumed to give protection against invasive H. influenzae type b disease (greater than or equal to 0.15 microgram/ml). In contrast, less than 10% of the infants who received PRP vaccine alone showed 2-fold or greater increases.
D000367:Age Factors; D000907:Antibodies, Bacterial / Q000032:analysis; D000942:Antigens, Bacterial / Q000276:immunology; D001886:Bordetella pertussis / Q000276:immunology; D002986:Clinical Trials as Topic; D004168:Diphtheria Toxoid / Q000008:administration & dosage; D005260:Female; D006193:Haemophilus influenzae / Q000276:immunology*; D006801:Humans; D007223:Infant; D008297:Male; D008583:Meningitis, Haemophilus / Q000517:prevention & control*; D011135:Polysaccharides, Bacterial / Q000008:administration & dosage; D011897:Random Allocation; D013745:Tetanus Toxoid / Q000008:administration & dosage; D014765:Viral Vaccines / Q000008:administration & dosage / Q000276:immunology / Q000592:standards*
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D004168:Diphtheria Toxoid; D011135:Polysaccharides, Bacterial; D013745:Tetanus Toxoid; D014765:Viral Vaccines