Immunity to Tetanus Induced by Combined Alum-Precipitated Diphtheria and Tetanus Toxoids

Ramon and his associates in their many studies on active immunization with tetanus toxoid (not alum precipitated) have demonstrated that further stimulation with toxoid results in the rapid formation of tetanus antitoxin. On this continent Sneath and Kerslake,1Jones and Moss,2Gold,3Hayden and Hall4and Hall,5among others, have corroborated the results of the French workers. Their studies deal largely with nonallergic adults. In my previous study6on the appearance of tetanus antitoxin in the blood serum following two injections of 0.5 cc. each of combined alumprecipitated diphtheria and tetanus toxoids, special reference was made to the influence of age and the interval between injections. It was also shown that 94.6 per cent of a group of 186 allergic children attained a protective level of tetanus antitoxin, the critical level being placed at 0.01 American unit of antitoxin per cubic centimeter of blood.