TETANUS IS AN ACUTE AND OFTEN FATAL DISEASE CAUSED BY AN EXTREMELY POTENT NEUROTOXIN PRODUCED BY C TETANI.
PROTECTION AGAINST DISEASE IS DUE TO THE DEVELOPMENT OF NEUTRALIZING ANTIBODIES TO TETANUS TOXIN. A SERUM TETANUS ANTITOXIN LEVEL OF 0.01 IU/ML, MEASURED BY NEUTRALIZATION ASSAYS, IS CONSIDERED THE MINIMUM PROTECTIVE LEVEL.
DIPHTHERIA IS AN ACUTE TOXIN-MEDIATED DISEASE CAUSED BY TOXIGENIC STRAINS OF C DIPHTHERIAE.
PROTECTION AGAINST DISEASE IS DUE TO THE DEVELOPMENT OF NEUTRALIZING ANTIBODIES TO DIPHTHERIA TOXIN. A SERUM DIPHTHERIA ANTITOXIN LEVEL OF 0.01 IU/ML IS THE LOWEST LEVEL GIVING SOME DEGREE OF PROTECTION.