An evaluation of diphtheria--tetanus (adult) vaccine in unselected human volunteers.

One hundred unselected adult volunteers received an adult diphtheria (less than 2 Lf)-tetanus (greater than or equal to 40 IU) adsorbed vaccine without prior Schick testing. No volunteer had a moderate or severe reaction although 39% complained of a transient sore arm. Only 10% reported local erythema. Of the study group, 37/43 (86%) patients who were initially seronegative for diphtheria attained levels normally considered as seropositive. The results confirm the safety and efficacy of adult diphtheria-tetanus vaccine and allow its recommendation for use in 'at risk' individuals without the need for prior Schick testing.