THE STATUS OF VACCINE AND SERUM THERAPY IN OPHTHALMOLOGY

The immunization treatment of infectious diseases is conducted by the introduction into the system of (a) substances—antigens—which stimulate the tissues to the production of antibodies ("active" immunization); and by the introduction of (b) antibodies that are already formed ("passive" immunization). To the first class of substances belong tuberculin and the bacterins; to the second the serums (substances containing antibodies). If the powers of the tissues of an individual are exhausted so that they can no longer respond to the stimulus of an antigen it is useless and even deleterious to introduce the antigen. Hence the necessity for knowing the condition of the individual in this respect and of avoiding overdosage. In the introduction of antibodies (serums) the conditions of the tissues relative to their ability to develop antibodies is not a part of the question. The problem here is how much of antibodies is required and how much the tissues