Booster response to the tetanus and diphtheria toxoid carriers of 11-valent pneumococcal conjugate vaccine in adults and toddlers

We measured the tetanus and diphtheria antitoxin responses after administra tion of one dose of a mixed carrier (tetanus and diphtheria toxoids) 11-val ent pneumococcal conjugate vaccine (PncDT) in 20 Finnish adults (mean age 2 6.1 years) and 20 Finnish (mean age 23.2 months) and 23 Israeli (mean age 1 8.5 months) toddlers. The vaccinees had previously been immunised with mult iple doses of vaccines containing diphtheria and tetanus toxoids. A double- antigen ELISA was used to measure the antitoxin concentrations. PncDT induc ed significant booster responses in both adults and toddlers to the tetanus and the diphtheria carrier proteins. Thus, the effect on the tetanus and d iphtheria immunity of multivalent conjugate vaccines containing tetanus and diphtheria toxoids as carriers needs to be evaluated before such vaccines are routinely implemented. (C) 2001 Elsevier Science Ltd. All rights reserv ed.