Years.Persons Treated.Deaths.Mortality per cent.
18862671250.94
18871770140.79
1888162290.55
1889183070.38
1890154050.32
1891155940.25
1892179040.22
1893164860.36
1894138770.50
1895152050.33
1896130840.30
1897152160.39

The following table gives the number of individuals treated who had been bitten by animals which had been proved rabid by successful inoculation of other animals, and of those bitten by reputedly rabid animals, and their respective mortality.

Died.Mort. per ct.
Bitten by animals proved rabid by inoculation2,872200.69
Bitten by animals pronounced rabid by veterinarian12,547610.48
Bitten by animals suspected of rabies4,747150.31
Average mortality 0.46

The Pasteur treatment by its great success in persons who have already been bitten has in a great measure robbed hydrophobia of its terrors, only it must be resorted to as early as possible in the period of incubation. It has also been advocated as a means of immunizing subjects that have not been bitten but are more or less liable to be so, and on this basis a large number of dogs have been passed through it. This is not likely to be adopted in the case of the human being, the more so that a few, although on the whole a very limited number of persons, have developed rabies long after the taking of the Pasteur treatment. This has been attributed to the retention of latent germs in the system, and argues besides a remaining susceptibility to the poison.

In spite of its brilliant success and the great boon it has been to humanity, the Pasteur treatment is not an ideal one. Its success does not consist in an entire extinction of rabies, but merely in the reducing of its evil results; its success is indeed based on a preservation and propagation of the germ and a continuous danger of infection of new subjects; finally, the proposition to end the disease by passing the whole canine race through the treatment, is open to the objections that this would require a fabulous outlay, and that even then some rare cases are not found to be fully protected. To continue the disease, when it may be exterminated, and to palliate its results by the treatment of generation after generation of dogs, must be promptly condemned by the political economist, to say nothing of the consideration of probable human infection.

Orrotherapy. It is not surprising that essays were made in the line of serum treatment. Babes and Lepp in 1889 had some encouraging results in transferring the blood of an immune animal into a healthy one. But Tizzoni, Schwarz and Centanni have especially worked out this method. These have shown that the blood serum of immunized animals destroyed the virulence of the rabic poison, whether mixed with it before injection, or injected with it, or injected within twenty-four hours afterward. A very small amount of the serum is required and though delayed until the end of the first half of the incubation period, it is only necessary to multiply the amount by six or eight times. In this it has a great advantage over the antitoxin of diphtheria or tetanus, the former of which has to be multiplied 20 to 100 times, and the latter 1000 to 2000 times in the later stages of incubation. Further, it is possible by drying to secure the serum in a permanent form which will remain active for a length of time if secluded from air and light.

This has the decided advantages over the Pasteur treatment, (1) that it employs the antitoxin already formed instead of waiting for its formation in the body of the subject injected with the attenuated virus, and (2) that it does not introduce into the system a virulent germ capable of propagating in a favorable medium, but only an agent which is antidotal to that germ.

It has the disadvantage as compared with Pasteur’s method that its action is purely therapeutic in the sense of acting as an antidote, while it produces no permanent immunity. It does not like the toxins educate the cells to produce an encrease of antitoxin, and it can only protect so long as it remains in the system. Whenever it is eliminated or destroyed, the susceptibility to rabies returns. Hence it is important to continue its administration as long as the microbe remains in the system. As in tetanus and diphtheria antitoxin treatment, it is also important to destroy the microbe and its toxins in the infection wound.

The animal which is to furnish the antitoxin is immunized as in the Pasteur method by a succession of graduated doses of rabic virus. After a treatment of 20 days the rabbit or sheep furnishes a serum which is protective when injected in the proportion of 1 of serum to 25,000 of body weight, even though its use be delayed until 24 hours after the introduction of the virus. The sheep can be immunized in 12 days by doses of 0.25 gramme of emulsion of the infected cord to every kilogramme of body weight. To maintain the serum at its highest standard the treatment must be repeated at intervals of 2 to 5 months, as the animal may be able to bear it without loss of condition.

Treatment with Sterilized Brain Matter from a Rabid Animal. In 1886 I sterilized with heat an emulsion of the spinal cord of a man who died of hydrophobia and injected two rabbits with 3 one drachm doses each, and a third with 4 one drachm doses on as many successive days. These rabbits were afterwards inoculated with virulent spinal cord and remained well for nine months, while three control rabbits injected with virulent cord, but which had received no previous treatment died rabid.