Adult Immunization

Abstract

THE incidence of allergic reactions to diphtheria toxoid was reduced in adult immunization by a combination of toxoid purification and drastic dose reduction.^{1 , 2} A previous study² described such a low-dose diphtheria prophylactic combined with a conventional dose of tetanus toxoid. In the course of extensive clinical trials, evidence emerged that reactions encountered were attributable to the tetanus-toxoid component. This was somewhat unanticipated because natural immunity to tetanus cannot occur in any manner analogous with that of diphtheria. In a study of this phenomenon² it was concluded that these reactions occurred in previously immunized persons and that they were age dependent, . . .