HY'DROPHO'BIA (Lat., from Ck, hydrophobia, from ilfpockafioc, hydrophobos, dread ing water, from Gdx.,pJaydor, water 06,10c, ',hobos, fear), or also called LYSNA. An acute infectious disease of warm-blooded animals produced in man by the implantation of a spe cific virus through the bite of an animal sick with the disease. This disease has been known since the earliest historical times. Denmeritus of .1bdcra gave an ,tevount of it in the fifth cen tury BA'. Aristotle in the fourth century tt.c. described it. C'elsus, 'Lc. 21. detailed some of its symptoms. Xenophon. ()yid, Vergil, I lorace, threh. all referred to rabies in their works. Boer hanve (q•v.) and Van S•ieten described the dis ease intelligently. •John Hunter (q.v.), INIagen die (q.v.), Marochetti, Mnrgagni, Trousseau. and all wrote of it. l'onatt (15450), the cele brated veterinarian. considered rabies at length in his hooks, and relied nn early cauterization with nitrate of silver to obviate infection. Yet after being bitten seven limes with impunity, ho is reported to have died of rabies at the last. Virchow and \' in propagated the dis by the hypodermie injection of saliva of a rabid animal. .After many others had added to our knowledge of hydrophobia, Pasteur (q.v.), in 1sti2. began to treat the disease with scientific accuracy.
The geographic distribution of the disease is wide. It has been found in f:reenland, where it was epidemic in ISfin; in Constantinople. whero it prevailed in 1:39: in Egypt, in London, in Ilainburo.. in Saxony, in Bavaria, and in many parts of the United States, the prevalence of the disease in \Vashite?ton. 1). C., in 18'9!)-1900 rais ing grave apprehension. In Russia and Siberia very many instanees of rabid wolves have been recorded. The disease is found most frequently in the dog, the wolf, the eat, and the cow. The skunk. also, seems to be peculiarly liable to Hydrophobia, and the disease in this animal has been eonsidered distinct and worthy its own name of rabies mephitica. A careful considera tion of all the known facts, however, leads to the conclusion that the disease is one to which all the lower animals, and man also, are liable; that it is protean in its manifestations. chiefly because of the thousand and one concomitant circumstances and elements; and that the collected statistics are mostly so tainted, from manifold sources of error, that they need to be scanned and sifted with the utmost discretion and care. It is. how
ever, safer to treat every skunk-bite as though certainly by a rabid animal, since in most eases the facts cannot be known. (The curious will find the question most interestingly discussed in a candid manlier in Coues's Fur Bearing Ani mals.) The nature of the infecting virus is as yet unknown. It is probably found in the saliva. In man there is a variable incubation from three weeks to six months. the period depending large ly on the site of the infection. Wounds about the neck and face are especially unfavorable in prognosis; next are those of • the hands. Punc tured wounds, because of the difficulty of cauter izing them, are most dangerous. Three stages are described. In the premonitory stage there is pain. numbness, or irritation about the bite. Irritability. nervousness, and depression are com mon. In the stage of excitement there is great hyperwsthesia. Almost any slight stimulus will cause intense reflex excitability and convulsions. The muscles of deglutition are extremely rigid. or even paralyzed. and any attempt at swallowing may cause spasms of the throat and general con vulsions; these may even follow the thought of swallowing. The name hydrophobia is erroneous, and based upon false inferences from these facts. The sufferer from rabies does not fear water— he intensely desires it, as he is devoured with thirst, but he cannot swallow it. nor even "go through the motions" of swallowing. There is also a secretion in the throat and mouth of a thick. viscid mucus. with thickened saliva, and the effort to get rid of this with muscles refus ing to act. causes the bark-like cough and hawk so often described as like a The patient does not bark, and it is doubtful if he bites. The temperature rises, and the patient may become maniacal. This stage may last from one to four days. and then the paralytic stage In this stage the spasms stop, un consciousness supervenes for the first time, the action of the heart ceases. and the patient dies.