fear. There are trembling, loss of appetite, rubbing and eversion of
the upper lip, neighing, sexual excitement, and inclination to bite
and kick. Delirium may be suspected, but during the paroxysms the true
nature of the disease is betrayed by the unconquerable desire to bite,
kick, and otherwise injure those about him. He will even gnaw the
manger and kick the stall to pieces, or lacerate his fore limbs and
flanks with his teeth. In the early stages there is the same tendency
to lick and rub the wound, which becomes red and irritable, the same
red glaring or squinting eyes, and the same jerking of the muscles, as
seen in the dog, and the affection winds up in the same way, in
paralysis and death in four or five days.
Rabid cattle lose appetite, become very restless and excitable, grind
the teeth, lick the cicatrix, evert the upper lip, and otherwise show
sexual excitement, bellow often in a loud, terrified manner, as if
still apprehensive of the attack of the dog, paw and scrape the ground
with the fore feet, butt and kick viciously, have twitching of the
muscles, and finally paralysis and death in from four to seven days.
When paralysis is coming on the hind feet are often drawn forward as
in inflammation of the feet. The pulse and breathing are accelerated
during the paroxysms, but I have not found the temperature raised.
Rabid sheep and goats present the same general symptoms, bleat
hoarsely, but viciously, have sexual excitement, nibble the cicatrix,
have muscular weakness, emaciation, and paralysis, and die in from
five to eight days.
Rabid swine show much fear, restlessness, and excitability, hide under
the litter, start violently at noises, grunt hoarsely, champ the jaws,
show a great disposition to bite and to gnaw and tear objects to
pieces, have dark red, glaring eyes, gape and yawn, and become weak
and paralytic. Breathing is often labored, and the mucosæ and white
skin assume a dull red or leaden hue. Death ensues as early as the
fourth or fifth day.
In Herbivora and Omnivora a paroxysm is usually induced by the sight
of a dog--a fact of importance in diagnosis.
Rabid skunks have naturally received but little study. They tend,
however, to steal up to men and animals and bite some exposed part of
the body, like the finger, ear, or nose, and as stealthily retire. It
is claimed that their odorous secretion is suppressed.
Symptoms of Hydrophobia in Man.
In some cases the prodromata are altogether omitted, the disease
setting in suddenly with spasms of the pharynx and inability to
swallow. More commonly, the premonitory symptoms last from one to
three days. The first symptom is often an itching, prickling, or more
or less violent {899} aching in the seat of the bite, and even of an
aura, a numbness, or shooting pain extending from that point toward
the heart. In such cases the wound is red or bluish, and even swollen.
In other cases there is chilliness, a general feeling of headache,
malaise, and prostration, with lack of appetite or nausea, gloomy
forebodings, taciturnity, nervous excitability, and restlessness. That
restlessness which in patients cognizant of the consequence of the
bite often induces insomnia during incubation, now often shows itself
in an inability to keep quiet or to remain in one position or
place--the exact counterpart of the initial restless stage shown in
the canine patient. The sleep is now even more broken and unrefreshing
and disturbed by fearful dreams. The restlessness soon merges into
intense nervous irritability. Though devoured by thirst, the patient
is afraid of water, and the attempt to drink will cause slight spasms
with a sensation of filling of the throat and difficulty of
deglutition. Even the air blowing upon his surface produces nervous
irritation and apprehension, and a sudden glare of sunshine or other
strong light is still more injurious. The pulse is increased in
frequency, hard, and small; the breathing accelerated, oppressed, with
at times yawning, sighing, or sobbing; there is some redness of the
fauces, vascular injection of face and eyes, with, in some cases,
dilated pupils; nausea or oppression at the epigastrium, sometimes
vomiting; and usually constipation, which cannot, as in dogs, be
referred to the earth, sand, and unsuitable materials swallowed.
Intelligence is unimpaired.
With or without some or all of the premonitory symptoms above
described the patient is sooner or later seized with constrictive
spasms of the pharynx and respiratory muscles, the immediate occasion
being an attempt to swallow liquid or some sudden fright or
excitement. So great is the agony produced by this attack that, though
consumed by thirst, the patient will rarely afterward attempt to
drink, and the mere sight or offer of water, the noise of liquid
flowing from one vessel to another, or even the sight of the vessel in
which liquid was contained, suffices to bring on a violent paroxysm.
This hydrophobia is peculiar to the human being suffering from this
disease, being rarely seen in rabid animals; and it serves to
enormously enhance the agony and horror of the affection. During a
paroxysm the dyspnoea is usually extreme; there is a gasping or
sighing respiration, and shrill, inarticulate sounds or screams are
emitted which have been likened to the bark of a dog. These are
manifestly due to the threatened suffocation rather than to an attempt
to bark. The sensations have been described as a rising of the stomach
into the throat, while others felt as if the throat had turned into
bone and could not admit nor pass on the liquid. The abdominal
contractions are often well marked, and retching and vomiting ensue.
This reflex irritability of the nerves of deglutition and respiration
is followed or attended by a condition of the most intense
hyperæsthesia and a great exaltation of the special senses. A deaf and
dumb child is said to have heard distinctly at this stage. There are,
besides, during a paroxysm, general muscular trembling and clonic
spasms of the muscles of the trunk and extremities. The facial muscles
are contracted, the nostrils dilated, the face and eyes red and
injected, and the pupils dilated, producing a spectacle of the most
intense agony. Even in the intervals the hyperæsthesia is so extreme
that the slightest touch of an attendant, a {900} current of air, the
approach of a candle, or even the ordinary tones of conversation,
produce extreme agitation and may precipitate a violent convulsive
paroxysm. The duration of the paroxysms and of the intervals varies
much, but in general terms the former increase rapidly in number and
severity, while the latter are correspondingly shortened. Restraint
serves to aggravate the paroxysm, while, according to Hunter, the
earlier and lighter ones may be relieved by running. The intense
excitement sometimes becomes manifest in the persistent talking, and
it is noticeable that the patient is free from mental delusions. As it
is impossible to swallow, the patient spits out the now viscid saliva
on all sides--a feature, like the fear of water, peculiar to man. As
the disease advances the paroxysms are marked by the most perfect
hallucinations and delirium, which impel the victim to acts of insane
violence toward every one and every thing about him. In these fits he
will use every available means of offence, even to the snapping of the
jaws, though on the subsidence of the fit he will often express the
greatest regret and warn his victims to be on their guard when he
finds another paroxysm coming on. In some few instances the delusions
continue even during the remissions, and the patient remains possessed
of a sense of suspicion and horror of all about him, and yet the fear
of being left alone is usually greater still. The convulsions may
become tetanic (as opisthotonos). They are habitually more severe in
men than in women and children. During a convulsion the victim will at
times become black in the face, and may die from suffocation,
apoplexy, or nervous exhaustion.
Should he survive this danger the final paralytic stage sets in. The
spasms gradually become weaker, reflex irritability is lessened, and a
period of quiet, and even comparative composure, may ensue, during
which the former sights and sounds fail to produce a paroxysm, and
some patients even recover the power of deglutition; but muscular
weakness and prostration become more extreme, the lower jaw may even
drop, and the viscid saliva drivel from the lips; finally, stupor
supervenes, and the patient dies in a state of profound coma or
complete exhaustion. This last stage lasts from one to eighteen hours.
Cases are met with in the human subject, as in the dog, in which the
paroxysmal stage is omitted in greater part or entirely. The patient
complains only of oppressed breathing, and sighs deeply when he
attempts to swallow, and paroxysms, if they occur at all, are very
mild. Decroix indeed claims that if a person suffering from
hydrophobia is kept in a dark room and perfectly quiet, no paroxysms
appear. The malady is, however, none the less fatal.
DIAGNOSIS.--The diagnosis of rabies and hydrophobia is not usually
difficult if the disease has progressed to its paroxysmal stage. The
most pathognomonic features are the fact of a bite by a rabid animal
and the evidence of lesions and an extraordinary irritability of the
medulla oblongata, inducing severe reflex spasms of the muscles of
deglutition and respiration under the influence of any peripheral
irritation. The clonic nature of the spasms and the entire absence of
trismus serve to distinguish it from tetanus. From pharyngeal anthrax
and diphtheria attended with spasm it is diagnosed by the extreme
exaltation of the special senses and the absence of any marked febrile
reaction; from acute mania by the difficulty of breathing and
deglutition, the more rapid heart-beats during {901} a paroxysm, and
by the marked hyperæsthesia and exalted reflex susceptibility, as well
as by the perfectly lucid intermissions; and from epilepsy, in that
the latter is not associated with the same hyperæsthesia, that the
paroxysm is not developed by noise, movement, attempts to swallow,
sight of water, etc., that the spasms are more universal, and that
they do not recur often, nor can they be roused by the causes
immediately producing those of hydrophobia. Hysterical cases can
usually be recognized by the imperfection of the symptoms; the
subject, not knowing all the manifestations of hydrophobia, naturally
fails to produce them.
The most difficult to distinguish from the genuine disease are those
cases in which hydrophobia occurs as a disease of the imagination, the
result of fear--the lyssophobia or hydrophobie non-rabique of the
writers. In these there is always the history of a bite; the cicatrix
even may have become the seat of congestive redness, itching, or
neuralgic pains, and these, acting on a susceptible brain, develop a
disease which is hardly distinguishable from true hydrophobia, and
which is quite as fatal if left to run its course. These cases have
usually less reflex susceptibility than genuine hydrophobia; the
attack mostly occurs shortly after some conversation on the subject,
and especially about the effects of the bites on others; and the
victim is seen to have a nervous organization, and may even be known
to have been subject to hysteria or other nervous disorder. At the
same time, the concentration of the mind on this subject sometimes
produces even structural changes in the medulla, and the reflex
susceptibility in co-ordination with the other symptoms may be almost
perfect. In a case reported a few years ago by Hammond the symptoms
appeared perfectly characteristic, and at the necropsy circumscribed
points of congestion were found near the roots of the vagus; yet the
dog that bit this man was said to be alive and well, and in the
absence of any successful inoculation from biter or bitten the case
must be presumed to have been lyssophobia.
Many cases with a more favorable issue are recorded. Bellenger had a
patient who had been bitten by his cat, and manifested violent
paroxysms of hydrophobia, but was instantly cured by the sight of the
animal in good health. Bouardel records that a man was bitten by his
dog, which afterward disappeared. He was seized with severe
hydrophobia, which continued for two days, when the lost dog was found
and presented to him, and the symptoms disappeared. Trousseau speaks
of a magistrate whose hand had been licked by his hound, which
immediately after attacked a flock of sheep, so that many of them died
of rabies. The master then manifested hydrophobia, but as death was
deferred beyond the usual time, he concluded it was not genuine and
recovered. Prof. Dick was called to visit a man who had been bitten by
a favorite dog while suffering from distemper, had manifested severe
hydrophobic symptoms, and had been given up by the attending
physicians. He succeeded in convincing the subject that as the dog had
had distemper, and as no two great diseases could coexist in the same
system, it could not have had rabies. In spite of the false premises,
this reasoning had the desired effect and the patient recovered. A few
years ago a boy twelve years old in Ithaca, N.Y., was bitten by a dog
supposed to be rabid, and in due time manifested hydrophobia, which
advanced rapidly until he was having a violent paroxysm every half
hour, and it was pronounced impossible for him to survive another day.
At this time I saw him, observed that he {902} had a nervous
organization, and was somewhat lacking in the hyperæsthesia of rabies,
learned that he had recently been gorging himself with Christmas
delicacies, and was now very costive; and, as there was no
satisfactory history of the dog, I at once suspected lyssophobia. The
friends and strangers who had come to condole with the parents and
feast on the horror were excluded, and the boy's attention fully
engaged in amusing pictures and conversation; the paroxysms were
omitted, and in two hours the patient, overcome by weariness, went to
sleep. Next morning he was still kept secluded and quiet, and two
enthusiastic students took up the rôle of keeping his attention
constantly engaged on whatever would interest him. The prima viæ was
relieved by medicine, and under a course of tonics the boy quickly
recruited, and at the end of a week went back to school.
In doubtful cases the test by inoculation may be tried. Inoculation
with the saliva of a man suffering from hydrophobia is manifestly
useless, since he must die before we can hope for the development of
the disease. But in the case of a dog having bitten one or more people
the inoculation of the virus on the brain of one or two other dogs
would ensure the development of the affection in the course of one or
two weeks, provided the first was rabid. The non-success of this
operation when practised on two dogs would provide the best possible
medicine for the diseased mind of the person bitten.
PATHOLOGICAL ANATOMY.--Post-mortem lesions are rather remarkable for
their inconstancy than for their specific characters. Hardly a single
lesion can be specified which may not be absent in particular cases,
yet some are so characteristic that, when taken along with the
symptoms during life, they very materially assist in diagnosing the
disease. Of the pathological appearances common to man, dog, and other
animals the following may be named: The body is greatly emaciated; the
rigor mortis is normal or nearly so; decomposition usually sets in
early; a white skin is livid, cyanotic, or petechial; the cicatrix is
often hardly noticeable even after the animal has been shaved; the
superficial veins, especially those of the neck and head, are filled
with black inspissated blood; the external mucous membranes are of a
dark livid hue, those of the mouth and nose being covered by a
tenacious mucous or muco-purulent secretion (in dogs they are usually
covered with earth or dust); the fauces, pharynx, and tonsils are
usually of a dark livid hue, and sometimes swollen; in other cases the
dark red hue and manifest swelling that obtained during life disappear
after death; similar lesions are found in the larynx, and I have seen
extensive erosions; the bronchial mucous membrane is reddened and
coated with a muco-purulent secretion (and in dogs with earth and
foreign bodies); the lungs are usually congested, often to the extent
of showing death by asphyxia; the heart and large blood-vessels are
filled with a black thick, venous blood, and the muscles, charged with
the same blood, have a dark reddish-brown hue; the stomach is usually
congested, sometimes to a port-wine hue, and is the seat of
blood-extravasations and even erosions; this congestion is often
present, though to a less degree, in the intestines; the mesenteric
glands and those in the vicinity of the pharynx are not unfrequently
enlarged and congested; a very constant feature is the entire absence
of proper food in the stomach and of chyme in the small intestine; the
liver is usually hyperæmic, {903} exuding on pressure the
characteristic dark blood, and it may be the seat of some granular
degeneration, but it usually retains its normal consistency; the
spleen is normal; the kidneys are hyperæmic and leaden or bluish gray,
and slightly cloudy on the surface (in dogs fatty degeneration of the
inner cortical layer is common even in health); the urinary bladder is
usually empty or contains a little turbid, yellowish, slightly
albuminous urine, while the mucous membrane is often covered with dark
reddish-brown petechial spots; the brain is usually hyperæmic, and,
together with its membranes, slightly oedematous, yet the lesions are
not constant either in kind or degree; the medulla oblongata usually
shows a similar condition, and even minute points of acute congestion,
but neither these nor the hyperæmia and oedema of the spinal cord can
be found in every case.
Some conditions are especially pathognomonic in the dog. In nearly all
cases of furious rabies the stomach is gorged with foreign bodies,
such as hay, straw, wood, coal, leather, portions of textile fabrics,
fæces, earth, sand, stones, pieces of iron, lead, etc., and the same
materials are usually found in the small intestine, while the large
intestines are empty. Portions of these foreign bodies are often found
in the bronchia as well, giving rise to circumscribed lobular
pneumonia. The significance of such matters when found in large amount
in the stomach of a dog which has been given to biting or other
symptom of rabies is very great, and if the stomach contains none of
the natural food of the animal and the duodenum no chyme, it may be
held pathognomonic of rabies. If, however, the materials are small in
quantity and mingled with natural food, and if the duodenum contains
chyme, the dog was probably not rabid. Dogs frequently chew and
swallow fresh leaves of grass, and those in detention gnaw and swallow
pieces of wood, cloth, horn, etc.; but these are used either as an
emetic or a teething-ring, and virtually imply that digestion is not
entirely abolished. Their presence, therefore, along with food does
not indicate rabies.
PROPHYLAXIS.--In view of the almost or quite constantly fatal issue of
rabies in man and animals, the main attention should be given to the
question of prevention. As the disease is perhaps never in our time
developed except as the result of contagion, we have the most perfect
guarantee that by suitably devised measures it may be absolutely
suppressed and excluded from any country. Even if we allow that a rare
case is at long intervals developed spontaneously, it is none the less
certain that the disease can be practically abolished, as nothing can
be easier than to nip the disease in the bud in the locality where it
first shows itself. Thus in Australia, Tasmania, and New Zealand
rabies has not yet appeared, though prevailing in the same latitude
and climate in both hemispheres. It reached Mauritius in 1813, and has
prevailed uninterruptedly since, while in Bourbon, immediately
adjacent and almost identical in geology, climate, flora, and fauna,
it is still unknown. The same truth is told in the entire extinction
of rabies in Berlin by the universal muzzling of dogs, as recorded
above. The immunity lasted for nine years, during which muzzling was
enforced. A more recent example of the same kind is found in Holland.
In 1875 universal muzzling was made obligatory in all communes where
rabid animals had been and in adjoining communes. From 1877 on the
disease was unknown save on the borders of {904} Belgium and Prussia
and in a very few dogs recently imported. Nearly all cases of
hydrophobia in man and animals being due to bites by rabid members of
the canine fraternity, a fundamental condition of all success in
prevention is the prohibition of its diffusion by dogs. For this
reason the following measures are requisite: 1st. All dogs should be
registered and heavily taxed. The number of useless dogs kept in every
community affords the greatest opportunity for the speedy diffusion of
the rabid germ whenever that has been introduced. Whatever tends to
reduce this number directly tends to the restriction and extinction of
rabies. 2d. Every dog should be made to wear a collar with plate
bearing the name and residence of his owner. All stray dogs without
such badge should be summarily shot by the police. This will secure
the payment of the taxes and the destruction of superfluous and
dangerous dogs. 3d. In all cities and counties where rabies has
existed within a year, and in the counties adjoining them, every dog
should be muzzled except when securely shut up or tied. All dogs found
at large without a muzzle should be promptly shot by the police. The
objection to muzzles is satisfactorily met by the use of the wire
muzzle, which impedes neither breathing nor drinking. 4th. Dogs and
cats suspected or known to have been bitten by rabid animals should be
at once destroyed, or if considered sufficiently valuable may be
confined in a secure cage for six months under veterinary supervision.
5th. Dogs which have bitten and are supposed to be rabid should be
similarly caged and placed under veterinary supervision. If rabid, the
symptoms will be fully developed in a few days, whereas if destroyed
at once the bitten party is liable to develop lyssophobia. 6th. Dogs
imported from countries where hydrophobia is known to exist should be
subjected to a period of quarantine of six months. 7th. Foxes, wolves,
badgers, martens, skunks, must be indiscriminately destroyed in
localities where they have become infected with rabies. 8th. The
disinfection or burning of the kennels where rabid dogs have been is a
natural corollary of the above.