Lesions: blood fluid or clot diffluent. Fauces, pharynx and larynx
congested, exceptionally ulcerated. In dog, mouth cyanotic, with
tenacious mucus, sublingual petechiæ and erosions, stomach contains
many foreign bodies, but no food, small intestines and cæcum empty,
and like stomach congested: petechiæ on skin and elsewhere, cutaneous
and cardiac veins gorged, hyperæmic liver, kidneys and bladder: brain
congested, capillaries dilated or blocked, hæmorrhagic, leucocytic
collections in lymph spaces, nerve cells swell up with hyaline bodies
near nuclei, and neuroglia has hyperplasia, especially near the
respiratory centre. Congestion of nerves. Leucocytosis. Therapeutic
treatment: Orrotherapy: of little avail. Nerve sedatives; darkness,
quiet, nutritive enemata, chloroform, chloral, etc. Prevention:
eradicate the virus; muzzle all dogs absolutely, under heavy penalty,
for one year; Gower’s view; examples of muzzling; collar with name and
owner, shoot all unmuzzled dogs, cage for 6 months bitten dogs and
cats, also all imported dogs, shut up in cage for 10 days all dogs
that have bitten; treatment of bites, tourniquet, cup, suck through
tube, wring wound, cauterize—hot skewer, cautery, mineral solid
caustic, mineral acids on pledget or through a tube; Pasteur method:
emulsion of spinal cord (of rabid rabbit) after aseptic æration in
vitro for 3 to 14 days, injected in graduated doses for 21 days, table
of doses, table of mortality; Orrotherapy: by blood serum of immune
animal: advantages, disadvantages—technique: Use of sterilized brain
matter from rabid animal: experiments; protection by snake venom.
_Pathological Anatomy._ The blood is fluid or the clot diffluent.
Congestion of the fauces, pharynx and larynx is patent during life but
may have disappeared after death. Yet I have seen extensive ulceration
of the vocal cords in a rabid cow. The congestion may extend to the
trachea bronchia and lungs. In _dogs_ the buccal mucosa is often
cyanotic, covered with a thick mucus, and may present sublingual
ecchymoses and erosions, and wounds of various kinds made by objects
bitten or swallowed. The stomach in the same animal is usually almost
pathognomonic, being filled with foreign bodies of all kinds—straw, hay,
hair, wood, coal, pebbles, pieces of metal, cord, leather, cloth, earth,
sand, etc.—the result of the depraved appetite. There is an absence of
normal food principles in stomach and small intestines and the cæcum and
colon are usually empty. The gastric mucosa is congested, and may be
wounded and its contents mixed with blood. Such a condition of the
stomach in a dog, that has been bitten, and which after a customary
incubation period has shown symptoms like those of rabies, is virtually
diagnostic.
The following lesions are common to man and animals: Marked emaciation,
cyanosis or petechiæ in skins that are naturally white, early sepsis,
cutaneous veins and heart gorged with dark inspissated blood, hyperæmic
liver and kidneys, and slightly congested, petechiated empty bladder.
The most important lesions, however are those of the central nervous
system. In seven cases out of nine, Gowers found these very distinct.
There were vascular disturbance, capillary dilatation, capillary clots,
minute hæmorrhages, and accumulations around the affected capillaries of
leucocytes occupying the lymph spaces. Benedikt and Babes attach much
importance to the formation of hyaline patches in the thickened walls of
the vessels and around them, compressing the vessels in some cases to
virtual obliteration. The nerve cells swell up, and show small hyaline
bodies in the vicinity of the nuclei, and these latter finally
disappear. Germano and Capobianco found in addition marked hyperplasia
of the neuroglia. Babes, who looks on these changes as pathognomonic,
takes a small portion of spinal cord, hardens it in alcohol for 24
hours, stains it with aniline red and examines for the characteristic
hyaline nodes.
These brain lesions have been found mainly in the medulla near the floor
of the fourth ventricle and the respiratory center, but they are also to
be found in other parts of the encephalon and spinal cord. The greater
constancy of the medullary lesions serves to explain the characteristic
symptoms.
Congestions of the peripheral nerves have also been found. Lüttkemüller
found in rabies a moderate increase of the white blood corpuscles and a
great number of microcytes.
_Therapeutic Treatment._ It was long thought that rabies was necessarily
fatal, as indeed nearly all developed cases are to the present day. For
this reason and much more on account of the risk of preservation and
propagation of the deadly germ, the attempts at curative treatment in
the lower animals have been looked on as utterly unwarranted or
absolutely criminal. Yet it is now known that very exceptionally a
recovery takes place, and in that case immunity for the future may be
counted on. Yet the frightful danger attendant on the preservation and
treatment of a rabid animal, may well forbid the keeping of any of the
lower animals affected by rabies unless it be in the safest seclusion
and for the production of immunizing or curative products.
_Orrotherapy_ with the blood serum of an immunized animal is of little
value, and attended by risk from the rabid animal, but will be noticed
below as a prophylactic.
In man when the disease is manifested, palliation has been obtained and
very exceptionally recovery, under darkness, quiet, nutritious enemata
and antispasmodics or soporifics. Among such antispasmodics and nerve
sedatives may be named chloroform, chloral, curare (3 alleged
recoveries), eserine (1 recovery), pilocarpin (1 recovery), morphia,
datura, atropia, and bromide of potassium. Others have recovered without
any medicinal treatment, so that the mildness of the attack must be duly
considered in every case.
_Prophylaxis._ The most effective way of preventing rabies is to
eradicate the virus from the country. All immunizing measures resorted
to after the infecting bite has been sustained, are of little value as
compared with this, they may save the bitten individual, but they do
nothing to prevent others from being bitten in the future, and
indirectly they contribute to the maintenance of the disease by drawing
attention from such radical measures as would rid the country forever of
the scourge. In his great work on Diseases of the Nervous System, Gowers
puts this not a whit too strongly when he says: “The enforced muzzling
of dogs for a period of one year would almost certainly stamp out the
disease. That such a measure is not adopted is a national disgrace,
which is accentuated by the fact that the Government derives part of its
revenue from a tax upon dogs. The opposition to the use of the muzzle is
one of the strangest developments of morbid sentiment. There are
apparently thousands of well-meaning people who would prefer that
hundreds of dogs should perish every year of a painful disease, that
many human lives should be annually lost, and scores of persons should
be subjected for months to acute mental agony—rather than that dogs
should be made to wear an apparatus which causes them a trifling
annoyance. This perverted sentiment ought to be met with universal
abhorrence as a disgrace to humanity.” Such a statute, backed by a
penalty in some degree commensurate to the homicidal criminality of the
person who would leave his dog free to inflict this horrible disease on
humanity would doubtless be effectual, but some nations have such laws
on their statute books, and yet allow them to become dead letters.
Others have enforced them to good purpose. Berlin in 1853 had many cases
of rabies and muzzling was enforced. In three years the disease was
completely eradicated and the city enjoyed nine years of immunity or so
long as the law was enforced. Similar successes were met with in
Holland, new cases occurring only on the borders or in imported dogs.
London in 1889 had 123 cases and muzzling was enjoined. In 1892 the
cases were reduced to 3, and the muzzling law was suspended, and a
steady yearly encrease resulted, until the 1st three months of 1896
furnished as many as 72 cases.
In the absence of this radical measure muzzling should be enforced for a
year in any locality where a case of rabies has occurred, and every dog
should wear a collar with the name and residence of his owner inscribed
on it. All stray dogs and all unmuzzled ones should be summarily shot.
Dogs and cats that have been bitten by rabid animals should be destroyed
or shut up in cages for six months under veterinary supervision.
Imported dogs should be similarly secluded. Dogs that have bitten
animals or men should be shut up for ten days under supervision, when,
if rabid, the animal will develop unequivocal symptoms.
_Treatment of bites._ Absorption from a wound in a limb may be prevented
by applying a tourniquet. Wounds on the body may be cupped, or sucked
through a tube. Or the wound may be wrung to encrease the flow of blood.
As soon as possible it should be thoroughly cauterized. A hot skewer, a
Paquelin cautery, a stick of silver nitrate or zinc chloride or caustic
potash or a crystal of cupric sulphate will meet this end. If liquid
caustics are to be employed they can be applied to all parts of the
wound by means of a pipette, a glass tube, or swab.
With thorough cauterization shortly after the bite there is practically
nothing to fear, and even if it has not been applied for hours after, it
is still valuable in destroying the poison left in the wound from which
a continuous infection of the brain, by the transmission of the unknown
germ and its toxins, would otherwise take place. It has besides in the
human being a good moral effect against lyssophobia by giving the bitten
person a certain sense of protection.
_The Pasteur Method._ This is based on the fact that the spinal cord of
the tetanic rabbit when removed aseptically, and kept _in vitro_ in a
dry atmosphere, loses in virulence day by day, until on the fourteenth
day it is harmless. To render the air more drying, caustic potash is
introduced into the flask. The culture of the poison in rabbits
intensifies its virulence, until the virus becomes the strongest known
and when inoculated subdurally, reduces the incubation to six or seven
days.
In Pasteur’s early experiments he began injecting the emulsion of the
cord desiccated for 14 days, following with that of the 13th day, and so
on to that of the 5th. It was soon found that this was comparatively
ineffective when inoculation had been made with a strong virus or in a
large dose, and the treatment for such cases was modified to what is now
known as the intensive method. The weaker forms of the virus are given
at shorter intervals on the first days of treatment, and the stronger
forms repeated again and again, and, in place of a 15 days, course of
treatment, this is extended to 21 days. The following table illustrates
the course:
│ _Number of │
_Day of │ Days that │
Treatment._ │ cord had │_Dose Injected._
│ been │
│desiccated._│
───────┬────────┼────────────┼────────────────
1st day│morning.│ 14 days. │ 3cc.
„ │ „ │ 13 days. │ „
───────┼────────┼────────────┼────────────────
„ │evening.│ 12 „ │ „
„ │ „ │ 11 „ │ „
───────┼────────┼────────────┼────────────────
2d „│morning.│ 10 „ │ 3cc.
„ │ „ │ 9 „ │ „
───────┼────────┼────────────┼────────────────
„ │evening.│ 8 „ │ „
„ │ „ │ 7 „ │ „
───────┼────────┼────────────┼────────────────
3d „│morning.│ 6 „ │ 2cc.
„ │evening.│ 6 „ │ „
───────┼────────┼────────────┼────────────────
4th „│ │ 5 „ │ 2cc.
5th „│ │ 5 „ │ 2cc.
6th „│ │ 4 „ │ 2cc.
7th „│ │ 3 „ │ 1cc.
8th „│ │ 4 „ │ 2cc.
9th „│ │ 3 „ │ 1½cc.
10th „│ │ 5 „ │ 2cc.
11th „│ │ 5 „ │ 2cc.
12th „│ │ 4 „ │ 2cc.
13th „│ │ 4 „ │ 2cc.
14th „│ │ 3 „ │ 2cc.
15th „│ │ 3 „ │ 2cc.
16th „│ │ 5 „ │ 2cc.
17th „│ │ 4 „ │ 2cc.
18th „│ │ 3 „ │ 2cc.
19th „│ │ 5 „ │ 2cc.
20th „│ │ 4 „ │ 2cc.
21st „│ │ 3 „ │ 2cc.
Under this treatment the system becomes educated in the production of
antitoxins, and perhaps also in phagocytosis so that when subjected to
the lethal doses of three, four, five and six days preservation, it
successfully resists them. The most conclusive argument in favor of its
efficacy is this undeniable fact that the individual escapes death under
injected doses which in any unprotected system would prove fatal.
The results as given by the report of the Pasteur Institute are
furnished in the following table, from which are excluded such cases
only as developed the disease during the course of treatment, which
therefore remained incomplete.
_Years._ _Persons Treated._ _Deaths._ _Mortality per cent._
1886 2671 25 0.94
1887 1770 14 0.79
1888 1622 9 0.55
1889 1830 7 0.38
1890 1540 5 0.32
1891 1559 4 0.25
1892 1790 4 0.22
1893 1648 6 0.36
1894 1387 7 0.50
1895 1520 5 0.33
1896 1308 4 0.30
1897 1521 6 0.39
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
inoculation 2,872 20 0.69
Bitten by animals pronounced rabid by
veterinarian 12,547 61 0.48
Bitten by animals suspected of rabies 4,747 15 0.31
————
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.
Puscarin and Vesesco have shown that the virus is rapidly weakened by
heat up to 60° C. at which point the virulence is destroyed. It becomes
easy therefore to secure in this way a toxin uncomplicated by any living
microbe.
Theoretically the sterilization and use of infecting nervous substance,
should share with the Pasteur method the advantage of the selective
action of the medullary matter in uniting with the toxins and robbing
them to a greater or less extent of their toxicity. It has the
additional recommendation that it introduces no living germ, and thus
obviates any possible danger of the propagation of disease through the
animal operated on.
Fernandez claims an immunity from rabies for dogs that have survived the
bite of a viper. Many facts and experiments are adduced in support of
this.