Experience With Alum Precipitated Toxoid in Virginia and Observations on the Reaction Following Its Use

Abstract

Of 1765 Schick-positive white or colored persons mostly of school ages given 0.5 or 1 cc. of diphtheria toxoid, alum precipitated (12.5-31.5 Lf per cc), 94.4% were Schick-negative 2 months later. 347 similar persons showed 95.1% Schick-negative on a first re-test one year after similar toxoid treatment. Schick tests on 1636 persons indicate that "the durability of immunity produced by alum precipitated toxoid is not less than that which is produced by natural causes or by other diphtheria immunizing agents." Local and general reactions were no greater in a small group getting 1 cc. of alum precipitated toxoid than in a similar group getting ordinary toxoid; but of 112 individuals getting a single lot of alum precipitated toxoid, 12 developed sterile abscesses requiring surgical attention.