Sustained Efficacy During the First 6 Years of Life of 3-Component Acellular Pertussis Vaccines Administered in Infancy: The Italian Experience

Abstract

The persistence of protection through 6 years of age suggests that the fourth DTaP dose could be postponed until preschool age in children who received 3-component acellular pertussis vaccines in infancy, provided that immunity to diphtheria and tetanus is maintained. Additional booster doses could be administered at older ages to reduce reactogenicity induced by multiple administrations and to optimize the control of pertussis in adolescents and young adults.