Experiments on Animals

by Stephen Paget

It would be foreign to the present purpose to pursue this matter further: for the other treatments, used by Baccelli and by Krokiewicz, and the sub-dural use of antitoxin, are also founded on experiments on animals; and the same will be true of any better method that shall be developed out of them.

The preventive use of the tetanus-antitoxin, for the immunisation of human beings or of animals, has given excellent results. Horses are very apt to be infected by tetanus; and the antitoxin has been used in veterinary practice, both for prevention and for cure. The curative results are not, at present, very good. But, as regards protection against the disease, there is evidence that horses can be immunised against tetanus by the antitoxin with almost mechanical accuracy. In some parts of the world, the loss of horses by tetanus is so common that their immunity is a very important matter; and that the antitoxin does confer immunity on them is shown by statistics from France and from the United States:—

1. France.—"The results of Nocard's method of preventive inoculations in veterinary practice are most striking. Among 63 veterinarians, there have been inoculated 2737 animals with preventive doses of antitoxin, and not a single case of tetanus developed; while during the same period, in the same neighbourhoods, 259 cases of tetanus developed in non-inoculated animals." (Med. News, 7th July 1900.)

2. United States.—"Joseph MacFarland and E. M. Ranck, in addition to a synopsis of the method of manufacture of tetanus-antitoxin, give some facts of interest and importance in regard to its use for prophylaxis and treatment. The studies were made upon several hundred horses used for the production of various immunised serums in one of the large laboratories of the United States. The horses, because of the constant manipulations, frequently became infected with tetanus, and in 1897 and 1898, when scrupulous cleanliness and disinfection were the only precautions employed to prevent the disease, the death-rate varied from 8 to 10 per cent. During 1899 nearly two hundred horses were subjected to systematic immunisation with tetanus-antitoxin; and, in spite of otherwise similar conditions, the death-rate descended to 1 per cent." (Medical Annual, 1901.)

The preventive use of the antitoxin has, of course, a very limited range outside veterinary surgery. Tetanus, thanks to the use of antiseptic or aseptic methods, not only in hospital surgery but also in amateur and domestic surgery, has become a very rare disease, except in tropical countries. It is no longer a "hospital disease"; and, even in war, it no longer has anything like the frequency that it had, for instance, in the War of the Rebellion. A student may now go all his time at a large hospital without seeing more than a very few cases. But, now and again, attention is called to some wholly unsuspected risk of the disease. For example, certain cases of tetanus occurred in Dundee among workers at the jute-mills there:—

"The last victim was a female worker in the jute-mill, who, six days after a crushed and lacerated wound of the foot, developed tetanus and died within twenty-four hours. Some of the dust, taken from under the machine in which the foot was crushed, was found to contain an unusually large number of tetanus-bacilli. The source of the jute used is India." (Medical News, August 1900.)

Again, at the Gebaer Anstalt at Prague, in 1899, an outbreak of tetanus occurred, with several deaths; but it was stopped when a preventive dose of the antitoxin was given to the new patients on admission.

Again, an amazing number of deaths from tetanus, in the United States, are due to wounds of the hands with toy-pistols. It is said that after the Fourth of July festivities in 1899, no less than 83 cases of tetanus were reported, 26 of them in and around New York. Almost all of them were due to gunshot wounds of the hand with toy-pistols: the unclean wad of the cartridge, made of refuse paper picked up in the streets, penetrates deep into the tissues of the hand, taking the germs of the disease with it, out of the reach of surgical disinfection. These cases of tetanus in the United States from toy-pistol wounds are so frequent, that immunisation has been recommended for them. The Medical News, 1st June 1901, has the following note:—"H. G. Wells states that tetanus is endemic in Chicago, the specific organism being present in the dirt of the streets. Every Fourth of July an epidemic occurs, because these bacilli are carried deeply into wounds before wads from blank cartridges.... The writer thinks that such cases should receive a prophylactic dose, say, 5 c.c. of tetanus-antitoxin, as soon as possible after the wound is first seen. It seems certain that if antitoxin prophylaxis were adopted, there would be no further Fourth of July epidemics, and this end would justify the means."

Again, a man might receive a lacerated wound under conditions especially favourable to infection: he might tear his hand in a stable where horses had died of tetanus, or he might cut his finger while he was working at the disease in a pathological laboratory, or he might receive a poisoned arrow-wound out in Africa. In any such emergency, he could safeguard his life with a protective dose of antitoxin.

It remains to be added, that the modern study of tetanus has brought into more general use the old rule that the wounded tissues in a severe case of tetanus should be at once excised. Before Nicolaier's work, while the theory still survived that the disease was due to ascending inflammation of a nerve, this rule was neither enforced nor explained.