Lack of consistent relationship between quantity of aluminum in diphtheria–tetanus–acellular pertussis vaccines and rates of extensive swelling reactions

The precise role that aluminum plays in local reactogenicity is not clear. We explored the relationship between rates of severe local reactions following the fourth and fifth booster doses of several diphtheria–tetanus–acellular pertussis vaccines (DTaP) and the quantity of aluminum contained in the different vaccines. Although there was a significant relationship between higher aluminum contents and swelling reactions >50 mm after dose 5, no relationship was seen with entire thigh swelling or with swelling >50 mm after dose 4. Because of the inconsistency of the data, a dose response between local reactogenicity and aluminum is questionable.