HYDROPHOBIA (derived from hydor, water, and pfu;bos, fear) is one of the diseases .hat are produced by animal poisons. A person is bitten by a mad dog or other animal. The wound gradually heals in the ordinary. manner. After an uncertain interval, usually ranging from six weeks to eighteen months, which is termed the period of incubation, the following symptoms appear: The patient experiences discomfort or pain at the seat of the bite. The cicatrix tingles or feels stiff or numb; sometimes becomes swelled and livid, and occasionally reopens, and discharges a peculiar ichor. The morbid sensations gradually extend from the original seat of injury towards the trunk. This period is termed the stage of recrudescence. Within a few hours, or, at longest, a very few days after the exhibition of this local irritation, during which time the patient has a sense of general discomfort and illness, the specific constitutional symptoms begin to manifest themselves; he complains of pain and stiffness about the neck and throat, finds himself unable to swallow fluids, and every attempt to do so— often even the sight or the sound of fluids—brings on a terrible paroxysm of choking and sobbing; and this continues for two or three days, till the patient dies from pun: exhaustion. The passage of a gust of wind across the face, or the waving of a mirror before the eyes, is often sufficient to excite these paroxysms. The mental condition in the last stage of 14k:111 cease varies; the, patient may he calm and trauqUil; generally he is irritable and apprehensive, and suspicious; and in most cases, a certain degree of delirium, or even mania, is associated with the irritability. Death most commonly takes place on the second or third day after the commencement of the specific symptoms.
Some medical writers have maintained that hydrophobia may occasionally he spon taneously developed in man, as is undoubtedly the case occasionally in the lower animals (the dog and wolf, for example); but even if this ever occurs, time instances are so extremely rare as not to affect the general statement, that in man time disease is the result of an animal poison, which is most commonly communicated by the bite of the dog, but which has also been produced by the bite of the wolf, the jackal, the raccoon, and the cat. The poisonous saliva is perfectly innocuous when applied to the unbroken skin; to produce its effects, there must be some abrasion of the cuticle; but according to the late Mr. Youatt, it may enter the system by mere contact with mucous 111e111 branes.
The disease is said to have been caused by the mere scratch of a cat; but as both cats and dogs frequently apply their paws to their mouths, the poisonous saliva may be introduced in this way by the claws.
There has been.much discussion as to what becomes of the poison. Is it immediately
taken into the system generally, or does it remain imprisoned in the wound or cicatrix for a time? In the latter case, we might successfully remove the poison any time between the infliction of the bite and the period of recrudescence; and that the poison is thus locally retained scents more than probable from the fact that at this period morbid phenomena of various kinds exhibit themselves at the seat of the wound, and that these phenomena are speedily followed by the characteristic symptoms of the disease.
Little need be said of the treatment of hydrophobia, for there is no well-authentieated case of recovery on record. The most distressing symptoms may, however, be alleviated by chloroform, opiates, the hot-air bath, etc. But although the disease cannot be cured, its development may be prevented by the early and complete excision of the bitten part, provided the situation of the bite allows of the free use of the knife. " If." says Dr. Watson, " the injury he so deep or extensive, or so situated that you cannot remove the whole surface of the wound, cut away what you can; then wash the wound thoroughly and for some hours together, by means of a stream of warm water, which may be poured from a tea-kettle; place an exhausted copping-glass from time to time over the exposed wound; and finally apply to every point of it a pencilof lunar caustic. If you cannot bring the solid caustic into contact with every part, you had better make use of some liquid escharotic; strong nitric acid, for example." Early excision is the only sure preventive, but if, for any reason, the operation has been omitted in the first instance, it is advisable, for the reasons already given regarding the probable latency of the poison, to cut out the wound at any period before symptoms of recrudescence appear. The reason why many neglect to have immediate recourse to excision probably is, that hydrophobia by no means follows, as a matter of certainty, the bite of a rabid animal. John Hunter states that lie knew an instance in which, of twenty-one persons bitten by a mad dog, one alone was infected. On the other hand, we have evidence that of one hundred and fourteen persons who were bitten by rabid wolves, sixty-seven, or more than one half, were victims to this disease. Although we have no very trust worthy evidence on a large scale, there is no doubt that the majority of persons who are bitten by a mad dog do escape the disease, even without taking any precaution. In many of these cases, the virus is probably removed by the teeth passing through the clothes.
The nature of the disease in the dog or other animal whose bite causes hydrophobia, is considered under RABIES.