Side-effects and Immunogenicity of Haemophilus influenzae Type B Polysaccharide Vaccine in a Multiethnic Pediatric Population

Abstract

Side-effects and immunogenicity of the Haemophilus influenzae type B polysaccharide vaccine (Hbpv) were reported following introduction in a multi-ethnic border population of 2- to 6-year-old U.S. military dependents. Eighty percent of 659 vaccinees were reported by parents to have no reactions within 48 hours following vaccination; 20% were reported to have local and/or systemic reactions. Each reaction was reported with one-fifth or less the frequency previously reported following DPT vaccination. Serologic data are presented on 114 of the vaccinees. The frequency of pre-vaccination levels reportedly associated with immunity ranged from a lower than expected 54% of 2-year-olds to an expected 86% of 5-year-olds. Post-vaccination levels reportedly associated with immunity ranged from a lower than expected 80% of 2-year-olds to an expected 93% of 5-year-olds. Of the 114 vaccines with serologic data, those with side-effects had serologic changes comparable to those without side-effects. There was no difference in side-effects or immunologic response across ethnic groups. Therefore, side-effects, immunologic responses, and ethnic group appear to be independent variables.