Comparative Effects of Diphtheria Toxoid and Toxin-Antitoxin as Immunizing Agents

Abstract

The value of diphtheria toxoid (anatoxin-Ramon), the modified toxin of diphtheria, in active immunization of man has been firmly established since Glenny's experiments with animals and Ramon's clinical demonstration of its efficiency. Its use on a broad scale has grown, particularly in France and in Canada. The lack of any extensive trial of toxoid in this country is, to a large extent, attributable to the strong foothold that prophylaxis with toxin-antitoxin has gained, following the impetus given to its popularization by Park and his collaborators.Through their laudable efforts, a marked reduction in the incidence of diphtheria has been effected in this country.The preference that toxoid has received in other countries within the last few years is the result of certain important advantages that have been recognized in the use of this material. These advantages have been emphasized by Ramon and Helie 1 in a recent report to the American medical profession, summarizing the experiences with toxoid.It is our purpose in this communication to report observations on the use of toxoid in a well controlled group of adults and also to explain, if possible, certain interesting phenomena incidental to its use.[any years ago, Ehrlich and others noted that diphtheria toxin solutions undergo deterioration with time and tend to lose their toxicity, retaining, however, their original power of neutralizing antitoxin. It has also been known for many years that a similar modification can be brought about by solution of formaldehyde. As early as 1904, these toxoid solutions were used in the immunization of horses for the routine production of antitoxin. Glenny and Hopkins,2 studying the effects of such a modified toxin, found this material to be of definite value as an immunizing agent. Using a concentrated form of toxoid,