Developments in Diphtheria Prophylaxis

In 1926, Glenny and others demonstrated that the antigenic power of alum-precipitated diphtheria toxoid was greater than that of the plain or nonprecipitated product. The newer preparation proved too irritating for administration to children, but it was later found that careful washing of the precipitate provided a product which could be used for human immunization. Alum-precipitated diphtheria toxoids often vary in potency even under regulated and well controlled methods of production. These variations, with their attendant problems of adequate diphtheria prophylaxis, prompted the author's search for a reliable and accurately reproducible prophylactic of high potency and stability. The work includes the description of a method for preparation of such a product and of the antigen and the alum precipitate. Data are presented which reflect the effect ofpH, temperature, formalin concentration, minerals, types of aluminum salt and other variables on the quality of the toxoid prepared. Considerable space is