Problems concerning the prophylaxis, pathogenesis and therapy of diphtheria.

The first part of this article on the prophylaxis, pathogenesis and therapy of diphtheria is devoted to an epidemiological survey of the results achieved with active immunization against the disease. From these results it can be concluded that active immunization has been largely responsible for the decrease in the morbidity and mortality rates which has taken place in the past half-century.In the second part, the authors deal at length with problems relating to the pathogenesis and therapy of the disease, discussing such subjects as the different types of diphtheria bacteria, the significance of non-virulent strains, the action of bacteriophages, the plurality of diphtheria toxin, the use of antibacterial sera, and the importance of the "avidity" of antitoxic sera.Finally, taking into consideration the data presented in the preceding parts, the authors put forward their views as to the cause of diphtheria, the measures which should be taken to control it, and the most satisfactory form of therapy.