ADVERSE REACTIONS AFTER DIPHTHERIA TETANUS BOOSTER IN 10-YEAR-OLD SCHOOLCHILDREN IN RELATION TO THE TYPE OF VACCINE GIVEN FOR THE PRIMARY VACCINATION

This prospective open study investigated adverse reactions in 527 scho olchildren to a diphtheria-tetanus (DT) booster given within a nationa l vaccination programme at 10 years of age. Evaluation was based on th ose whose immunization records showed that they had received either th ree doses of an adsorbed DT vaccine (n = 388) or a non-adsorbed DT-per tussis vaccine (DTP) (n = 69) for primary series vaccination. No diffe rences in systemic reactions to the booster between the two groups wer e observed. Local reactions were significantly (p < 0.001) more common 1 day after vaccination in children who had received DT for primary s eries vaccination: redness, 73% compared with 23%; swelling, 56% versu s 15%; and itching, 47% versus 21%. One and 2 weeks after the booster, itching was still more pronounced in the group who had received DT fo r primary series vaccination (p < 0.001 and 0.014, respectively). The study indicates that there was a real basis for the increase in sponta neous notifications of local side-effects to the school DT booster in Sweden. The most likely cause for the increase seems to be the alumini um adjuvant in the vaccine given for primary vaccination, a late and u nexpected consequence of a change in the infant immunization programme .