ABSTRACT
Levels of antibody in serum after infection with Haemophilus influenza type b or challenge with polysaccharide vaccine are highly variable. Convalescent-phase serum antibody to the capsular polysaccharide of H. influenzae type b was measured in two groups of patients with pathophysiologically distinct diseases, meningitis and acute epiglottitis. Antibody response after H. influenzae meningitis was subnormal. Mean levels of antibody, the distribution of antibody levels by age, and erythrocyte and genetic marker lymphocyte antigens were studied; all results suggested that these two groups of patients were genetically and immunologically different from each other. Evidence suggested that the magnitude of the important host immunologic response was under host genetic control.
