796 CHRONIC INFECTIOUS DISEASES. 



mentioned or really did not occur, must arouse the suspicion that they 

 were badly observed, or that there was an error of diagnosis. 



Opinions differ as to the length of its period of incubation. The 

 statements that hydrophobia has made its appearance twenty or thirty 

 years after the bite of a rabid animal, as well as those according to 

 which the disease has broken out as early as the second or third day, 

 are probably dependent upon imperfect observation. The shortest 

 term of incubation appears to be about eight or ten days ; the longest, 

 twelve or thirteen months. In the majority of instances, the malady 

 breaks out in about forty days after the reception of the bite. The 

 reasons for this inequality of the period of incubation are obscure. The 

 assertions of Marochetti, who claims that, during the incubative stage, 

 vesicles form beneath the tongue, and that, by destroying these vesi- 

 cles, the outbreak of the disease can be averted, have not been substan- 

 tiated. But there are numerous instances in which, toward the end 

 of the stage of incubation, and a day or two before the onset of the 

 malady, peculiar alterations have been observed in the wound or its 

 scar, for the wound has generally healed by this time. The bite as- 

 sumes a livid color, grows painful, and discharges a yellow ichor. 

 The scar, which has generally soon formed without remarkable symp- 

 toms, grows bluish red, swells, and sometimes breaks out afresh. 

 The patient also complains of painful sensations, shooting centripetally 

 from the wound or scar, or of a sense of numbness in the bitten mem- 

 ber. These disturbances at the point of entry of the virus are very 

 often wanting. 



The first or prodromic stage of the disease is marked by a peculiar 

 depression of the patient's spirits, amounting to an acute melancholy, 

 and which has caused the term stadium melancholicum to be applied 

 to this period of the disorder. The patient seeks solitude, is timid 

 and apprehensive, and either sits motionless and plunged in deep ab- 

 straction, or else is unable to rest at all. Some complain of an indefi- 

 nite feeling of dread and oppression, and sigh repeatedly without 

 any reason for so doing. Some are preoccupied with sad forebodings, 

 or, if aware of their perilous condition, are incessantly tormented by 

 dread of the onset of the malady. Sleep is restless and broken by 

 frightful dreams. The precursory signs of the spasmodic disturbance 

 of respiration, afterward to attain so terrible an intensity, soon super- 

 vene. The patient complains of pressure in the prsecordium, draws 

 profound, sighing inspirations, the diaphragm is depressed, the epi- 

 gastrium bulges, and the shoulders are drawn upward. This spas- 

 modic breathing is the first token of the tonic spasm of the muscles 

 of inspiration which causes such frightful torments in the second stage 

 of the disease. 



