Immunoglobulin E responses to diphtheria and tetanus toxoids after booster with aluminium-adsorbed and fluid DT-vaccines.

Immunoglobulin E responses to diphtheria and tetanus toxoids were investigated in pre- and postbooster samples of 104 children given, at 10 years of age, a DT booster with either an adsorbed (n = 51) or a non-adsorbed, fluid vaccine (n = 53). Vaccination with adsorbed DT is part of a national immunisation programme and represents the first regular booster given to these children, primarily immunised with three doses of adsorbed DT at age 3-6 months. The vaccines, with a content of 30 Lf of diphtheria toxoid and 7.5 Lf of tetanus toxoid per millilitre, were given for booster in a dose of 0.25 ml as a deep subcutaneous injection. In the prebooster samples, 3 and 14% had measurable IgE to diphtheria and tetanus, respectively. These rates rose to 94 and 92% in the postbooster samples, respectively. The median (range) of IgE to tetanus among recipients of the adsorbed vaccine was 0.59 PRU ml-1 (< 0.1-17.5), as compared to 0.27 (< 0.1-8.22) in the recipients of the fluid vaccine (p = 0.027). The median IgE response to diphtheria toxoid in the whole group was 1.8 (< 0.1-17.5), with no significant difference between the two vaccines (p = 0.76). There was no correlation between the IgE and IgG responses (r < 0.07, p > 0.5) but the two IgE responses as well as the ratios of IgG/IgE showed strong correlations (r > 0.7, p < 0.001). The study thus revealed unexpectedly high rates of IgE responses to diphtheria and tetanus toxoids in a regular DT booster vaccination programme, which were associated to high rates of local side effects.(ABSTRACT TRUNCATED AT 250 WORDS)