title: Age-related response to two Haemophilus influenzae type b vaccines.
abstract: Two types of Hib vaccines were compared for efficacy and safety in 71 normal children in three age groups: 36 to 72 months, 15 to 18 months, and 6 to 8 months. One vaccine contained the Hib-specific capsular polysaccharide, PRP; the second vaccine contained PRP combined with pertussis vaccine, PRP-P. A third vaccine, DTP, was administered to a control group for each age. Anti-PRP antibody levels were greater after vaccination with PRP-P than after PRP in all three age groups. Immunoresponsiveness to both vaccines increased with age. A  lower incidence of side effects was seen with both PRP (15%) and PRP-P (20%) than with DTP (56%). The results suggest that PRP-P is both well tolerated clinically and has greater immunogenicity than PRP.
mesh_terms: D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D002986:Clinical Trials as Topic; D004168:Diphtheria Toxoid / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology; D005334:Fever / Q000209:etiology; D006193:Haemophilus influenzae / Q000276:immunology*; D006801:Humans; D007223:Infant; D007252:Influenza Vaccines / Q000276:immunology*; D007273:Injections, Intramuscular; D007279:Injections, Subcutaneous; D010567:Pertussis Vaccine / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D013745:Tetanus Toxoid / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology; D014611:Vaccination
chemical_list: D004168:Diphtheria Toxoid; D007252:Influenza Vaccines; D010567:Pertussis Vaccine; D011135:Polysaccharides, Bacterial; D013745:Tetanus Toxoid