No abstract

SUMMARY The safety and immunogenicity of a Haemophilus influenzae type b conjugate vaccine was investigated in 103 infants immunised at 3, 5, and 9 months of age; the infants also received diphtheria, pertussis, and tetanus and polio vaccines. Side effects were compared with 99 matched infants receiving diphtheria, pertussis, and tetanus and polio vaccines only. No serious side effects were observed and the incidence of minor side effects was no greater in the recipients of H influenzae type b conjugate vaccine. Two doses of the vaccine (standard and low)were compared: geometric mean titres of serum anticapsular antibody rose from 0-11 [tg/ml before immunisation to 26-4 [ig/ml after three immunisations with the standard dose and 14-6