RESUMEN
The complex study of cell-mediated and humoral immunity characteristics, as well as nonspecific protective factors, in 30 diphtheria patients, 9 clinically healthy carriers and 54 healthy subjects was carried out. In healthy immunized subjects normal characteristics of all elements of immunity were observed in combination with high titers of antitoxins and sensitization of lymphocytes to diphtheria toxoid. In healthy carriers the presence of cell-mediated and humoral immunity to diphtheria was associated with disturbances of the metabolic activity of phagocytes and a decrease in the proliferation of lymphocytes in response to the mitogen. Diphtheria patients were found to have changes in all elements of immunity, especially pronounced in severe forms of the disease.