Multiple Antigen for Immunization Against Poliomyelitis, Diphtheria, Pertussis, and Tetanus. II. Response of Infants and Young Children to Primary Immunization and Eighteen-Month Booster

Abstract

A total of 298 children from 2 and one-half months through 5 years of age were observed, in order to study antibody response to diphtheria, tetanus, pertussis, and polio antigens in one vaccine. Sub- jects received either the quadruple vaccine or a standard DPT control vaccine. Those under 6 months of age received 4 primary inoculations, while older subjects received only 3. Two hundred and twenty-four completed the primary series, and 104 of these returned for an 18- month booster dose. Serum antibody results showed that the quadruple vaccine induced a satisfactory response to all antigen components. The 4th dose given to the younger infants brough their antibody levels in line with those obtained in older children with only 3 doses. The booster dose produced a uniformly high response to all component antigens, regardless of the age at which primary immunization was begun and regardless of the antibody level following the primary series. No clinical reactions of any serious consequence were reported or observed.