GEN. I. SPEC. VIII. Entasia Lyssa. Remote or causes un known. Various in pected, but without sufficient authority. These, however, are, in every instance, modifications of empathema, and especially of rage or fright, grafted on a highly irritable temperament, and henee associated with hysterical, or some other spasmodic motions. Of the remote or predisposing causes of this disease we predisposing know nothing. The excitement of vehement rage, putrid food, long continued thirst from a want of water to quench cidents sus- it, severe and pinching hunger, a hot and sultry state, or some other intemperament of the atmosphere, have been, in turn, appealed to as probable predisponents, but the appeal in no instance rests on any authority. That the Illustrated. stimulus of vehement rage will often produce a peculiar influence affecting the saliva, and rendering it capable, by a bite, of exciting the most alarming symptoms of nervous irritation we have just shown; but these symptoms are not those of lyssa; and the virus, whatever it consists in, appears to be of a different kind. Putridity is, perhaps, the ordinary state in which dogs and cats obtain the offal, on which, for the most part, they feed: they show no disgust to it, and it offers a cause far too general for the purpose. In long voyages, again, when a crew has been without water, and reduced to short provisions, dogs have been, in innumerable instances, known to die both of thirst and hunger without betraying any signs of genuine rabies. That a peculiar intemperament of the atmosphere may at times be a cause, it is impossible to deny ; but the disease, even when of spontaneous origin, has appeared under, perhaps, every variety of meteorological change, and seems to be far less common in hot and tropical regions than in those of a more moderate temperature: for it is not known, except by report, in South America, though it is said to have occasionally appeared in the West Indies, as I have been repeatedly informed by intelligent residents in those quarters; while M. Volney tells us that it is equally uncommon in Egypt and Syria, and Mr. Barrow, at the Cape of Good Hope and in the interior of the country, where the Caffrés feed their dogs on nothing but putrid meat, and this often in the highest degree of offensiveness. Rabies less common in torrid than in temperate climates. SPEC. VIII, Rabies. ever be ex It is not improbable that several of these may occasion- GEN. I. ally become exciting causes; but it is hence obvious that Entasia they are not competent of themselves to produce the dis- Lyssa. ease. Some of them indeed have been put to a direct Several of test, and have explicitly proved their incompetency. the above Thus in the wards of the Veterinary School at Alfort, may howthree dogs were shut up and made the subjects of express citing experiments. One was fed with salted meats, and totally causes, but restrained from drinking: the second was allowed nothing but water; and the third allowed neither food nor drink of any kind. The first died on the forty-first day of the experiment, the second on the thirty-third day; and the third on the twenty-fifth; not one of them evincing the slightest symptom of rabies. ex selves incompetent to produce the disease. Proofs of this assertion. The specific rabies less active and virus of volatile than many morbid poisons, hence all that are bit ten rarely suffer. Sometimes not more than one out of twenty: That the specific virus of rabies is less volatile and active than many other kinds of morbid poisons is clear from the fact that it is never found diffused in the atmo sphere, so as to produce an epidemy; that it never ope rates on those who are most susceptible of its influence cept when accompanied with a wound or inserted into the cutis*; and that, even in this case, it usually requires in mankind, and probably also in other animals, some auxiliary excitement to enable it to carry forward the process of assimilation for it rarely happens that all the men or quadrupeds that are bitten by a rabid dog suffer from the inoculation. Mr. Hunter, indeed, gives an instance in which out of twenty persons who were bitten by the same dog only one received the disease. This want of activity long interis a happy circumstance, as it affords an important inter- usually val for medical treatment, if we should ever be so fortunate as to hit upon any curative process that may be depended upon. At the same time I cannot avoid again to observe that as this virus is less volatile than most others, it is perhaps less indecomposible than any of them, and hence is capable of remaining in a dormant and unaffected state, in any part of the system, into which it has been received by insertion, for a far longer period than any • Trolliet, ubi suprà. and hence also the takes place between the injury and the disease. Virus also more inde composible than any any. GEN. I. SPEC. VIII. Entasia Lyssa. Rabies. Whether the acrimony becomes concentrat ed and ac tive by multiplication? No solid foundation other known contagion whatever. It is generally calculated, but I do not know upon what data, that of those who are exposed to the venom about one in four matures the complaint, and the rest escape. When the disease has once fixed itself among a large establishment of hounds, it has been said that the acrimony of the poison becomes more concentrated and active; operates through an unbroken skin, and even taints the atmosphere. There is, however, no solid foundation for such an opinion; and though the disease runs rapidly from one dog to another, and it may be difficult in many for such an opinion. cases to trace the marks of a bite, yet considering that the Whether smallest and most imperceptible scratch of a tooth may be capable of a sufficient medium of infection, and that every inoculated being received with dog adds to the sources from which it may be derived, out a wound there is no difficulty in accounting for such rapidity of spread without ascribing anomalies to the laws by which asserted by it is regulated. Heister, indeed, has given a case of lyssa, in one of the foreign collections, produced in a man by his having merely put into his mouth the cord by which the mad dog had been confined: but as in this instance there was probably some ulceration in the mouth and by Pal at the time, there is nothing marvellous in its production. or sore? Heister, marius. The effects in these cases ac counted for upon the common law of the disease. Proofs offered. Palmarius, in like manner, relates the case of a peasant who, in the last stage of the disease, communicated it to his children in kissing them and taking leave of them*. Yet unless we could be certain that there were no cracks or other sores on the lips, and no eruption on the cheeks of these children, the example affords no proof. I can distinctly state that I have seen the same intercommunication successively repeated between a rabid young man and a young woman to whom he was betrothed, and who could not be restrained from such a token of affection, without any evil consequences; notwithstanding that the patient was labouring at that time under hydrophobia and all the severest marks of the disease which destroyed him in a few hours afterwards, * De Morb. Contagios. p. 266. Paris, 4to. 1518. GEN. I. SPEC. VIII. Rabies. and had also a perpetual desire to spit his saliva about the room. M. Trolliet asserts not only that the virus Entasia will not permeate a sound skin, but that it is only con- Lyssa. tained in the frothy matter communicated from the lips; and that neither the blood, nor the secretions of any kind are tainted with it, or give rise to the disease, whatever scratch or other injury may be received during dissection. Has been denied that sometimes the virus can be pro pagated in any way from the human sub It has, still farther, been doubted whether the virus itself is capable of propagation from the human subject to any animal even by inoculation: but a bold experiment of M. Magendie and M. Breschet has completely settled this question; for on June 19, 1813, having collected upon a piece of linen a portion of the saliva of a rabid man in the last stage of the disease, they inserted it under the skin of two dogs that were in waiting, both of them Contradictin good health; of which one became rabid on the 27th of July, and bit two others, one of which also fell a victim to the disease just a month afterwards. ject. ed by ex periments. of Magen die and Breschet. Nervous system the quarter of immediate disturbance: but the ef fects refer red by some writers to the sanguiferous sys The general aggregate of the symptoms point forcibly to the nervous system as the immediate quarter of disturbar.ce. Such was the opinion of Morgagni, Cullen, Percival, and Marcet; and such indeed is the common opinion of the present day. By many writers, however, the effects have been rather referred to the sanguiferous system and regarded as a fever; Mangor describes it as a continued fever*; and Rush and many others as an inflammatory affection; Bader as a fever sui generis t. Nor is the difficulty in the least degree removed by dissection, for nothing can be more at variance than the appearances in different cases. Generally speaking the fauces and parts adjoining exhibit redness and inflamma- examined, tory characters. But while in some instances these are so considerable as to be on the point of gangrene, in others there is no inflammatory appearance whatever. Morgagni has examined and described bodies in both these tem tem and regarded as a fever or an inflam mation. Question and inflammatory ap pearances accounted for. Act. Havn. II. + Versuch ener neuen Theorie, &c. GEN. I. SPEC. VIII. Sometimes pearances. states. Rolfinc gives one or two decided cases of the latter sort*: while Feriar notices examples in which the inflammation of the fauces had spread over the whole esophagus and even the stomach +; and another writer has recorded an instance in which it had descended to the ileus, which was in a state of gangrene ‡. In some cases the encephalon, and even the spinal marrow, has appeared to be as much diseased as the fauces; the vessels turgid; the plexus choroides blackish; the ventricles loaded with water: though in the cases examined by M. Magendie, no such ap- which were confined to dogs, there was no appearance of inflammation either in the brain or spine. Sometimes the lungs have been inflamed, sometimes the liver, sometimes the vagina; while the blood, according to Sauvages, has been also found in a dissolved state, and, according to Morgagni, in a state highly tenacious and coagulable. From all which we can only conclude that owing to the violence of the disease, every organ is greatly disturbed, and those the most so that in particular cases are most severely affected. Riedel asserts that among dogs a highly offensive fetor of a peculiar character is thrown forth from every part of the body §: but I have not found this remark confirmed by the veterinary practitioners of our own country; and it certainly does not apply to mankind, with an exception or two that seem to depend upon some accidental circumstances; for Wolf informs us, that in one of his patients, and a patient that ultimately recovered, the blood stunk intolerably as it was drawn from a vein; neral conco- and a patient of Dr. Vaughan's complained of a most offensive smell that issued from the original wound, but of which no one was sensible except himself. In like manner the patient described by Dr. Marcet, towards the close of the disease, complained loudly of an intolerable stench that issued from his body generally, but without being Whether accompanied with an of fensive fetor. Seems to have been so in a few cases from some ca sualty, but not a ge mitant, Dissert. Anat. Lib. 1. cap. xii. † Medic. Facts and Observations, Vol. 1. |