The active immunisation of horses against tetanus / by J.B. Burxton.

  • Buxton, J. B. (James Basil)
Date:
[1921?]
Catalogue details

Licence: In copyright

Credit: The active immunisation of horses against tetanus / by J.B. Burxton. Source: Wellcome Collection.

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    Reprinted from The Veterinary Journal, December, 1921.^^ THE ACTIVE IMMUNISATION OF HORSES AGAINST TETANUS. By J. B. BUXTON, F.R.C.V.S., D.V.H. (Veterinary Superintendent. The. Wellcome Physiological Research Laboratories, Herne Hill, London). The clinical value of protective injections of tetanus antitoxin in horses and other animals is well known and has been definitely established as a result of prolonged usage. It is also well known that the passive immunity which is conferred upon man or animals by such means is necessarily of a transitory nature. While the elimination of the antitoxin in man is, because it contains heterologous or “ foreign ” proteins, naturally more rapid than is the elimination of the homologous serum from horses, it is, nevertheless, certain that after the lapse of a few weeks the amount of antitoxin remaining in the system of the horse is probably never sufficiently high to protect the animal against a fatal intoxication. It has long been known that more or less balanced mixtures of diphtheria toxin and antitoxin stimulate the body cells to produce their own antitoxin, and that the active immunity so produced persists for a very much longer time than does the passive immunity conferred ! by an injection of antitoxin alone. As long ago as 1907 Theobald Smith (Journal Med. Research, 1907, XVI, 359) suggested the possi¬ bility of protecting man against diphtheria by means of such mixtures, and subsequently showed that such an immunity could be produced j in experimental animals. The mechanism of this reaction was ascribed by Behring (Dentsch. Med. Woe he use hr., 1913, XXXIX, 873) to the instability of the union of toxin and antitoxin, so that after the injec¬ tion of such a neutral mixture into animals a certain amount of toxin becomes liberated and stimulates the body cells, which produce their own antitoxin. It is not finally decided whether this is so, or whether the action of antitoxin upon toxin is such as to render it incapable of producing its specific poisoning, while interfering to only a slight extent with the power of the toxin to cause the production of antitoxin in the animal; that is, converts it into a modified toxin which has lost its pathogenic but not its antigenic properties. -''in the process of the active immunisation of many horses against tetanus toxin in the preparation of tetanus antitoxin during the war he found that the injection of such neutral mixtures of tetanus toxin and antitoxin in non-immune horses produced a valuable active immunity.