Comparative Merits of New and Old Preparations of Diphtheria Toxin-Antitoxin

When the New York City Health Department laboratory workers first undertook to estimate the value of toxin-antitoxin in the practical immunization of children against diphtheria in 1914, it was essential to utilize an effective preparation. The ingredients of importance in such a preparation other than the antitoxin are the specific toxin that causes the production of antitoxin and the nonspecific products of bacterial growth and dissolution occurring in the cultures in which the toxin is produced. It is these nonspecific products that cause the local disturbance in sensitive persons. The antitoxin should be added in an amount just sufficient to lessen the excessive avidity cf the toxin for the tissues and so prevent painful reaction, but the amount of antitoxin should not be enough to rob the toxin of its immunizing effect. For a number of years previously, numerous animal tests had been carried out by Park with a mixture