COMPARISON OF A 3-COMPONENT ACELLULAR PERTUSSIS-VACCINE WITH WHOLE-CELL PERTUSSIS-VACCINE IN 2-MONTH-OLD CHILDREN

An acellular pertussis vaccine (DTaP) containing pertussis toroid, filamentous hemagglutinin and the 69-kDa outer membrane protein (pertactin) was compared with United States-licensed whole cell pertussis vaccine (DTwP) as a three dose sequence at 2, 4 and 6 months of age. Eighty infants were enrolled; 62 received DTaP and 18 received DTwP. Sixty-two infants had preimmunization and 1 month postimmunization sera available for pertussis antibodies. No infant experienced a serious adverse reaction. Significantly fewer infants in the DTaP group experienced irritability (P < 0.001) and moderate to severe injection site pain and redness (P < 0.001, and P = 0.03, respectively). The DTaP group also had significantly greater increases in geometric mean titers of antibodies against filamentous hemagglutinin (P < 0.001) and pertactin (P = 0.006). This three-component DTaP vaccine induced an antibody response to pertussis toxin, filamentous hemagglutinin and pertactin but caused fewer adverse reactions than DTwP when administered as a primary series of immunization to 2-month-old infants.