CANINE DISTEMPER 467 
disease. Urbean Leblanc in 1841 gave it the name of variola. 
Schantyr stated, in 1891, that canine distemper should be divided 
into three different diseases and that each is produced by a distinct 
species of bacteria. In 1899 Jess isolated a bacillus from the catarrhal 
secretions, blood, serous exudates and organs. He reports having 
reproduced the disease in dogs with pure cultures of this organism. 
Geographical distribution. Distemper in dogs is a wide-spread 
disease. It is- very common throughout America and Europe. It is 
stated that there is no country or climate in which the dog is exempt 
from distemper. 
Etiology. The specific cause of distemper has not been demon- 
strated. Ferry and also Torrey and Rahe have studied an organism, 
B. bronchisepticus, which they believe to be the specific cause. 
Carré has shown that the serous nasal discharge obtained at the 
outset of the disease possesses great virulence due to the presence of a 
virus sufficiently small to pass through certain filters. There is much 
need for further investigation into the etiology of this malady. Dogs 
are able to transmit the disease so long as they have any discharge, 
diarrhea or cough. They are said sometimes to be carriers after all 
symptoms have disappeared. Gray found that latent cases are often 
the source of the so-called “spontaneous outbreaks.” 
The period of incubation varies from 4 to 15 days.* In the so-called 
latent cases it may be much longer. 
Symptoms. The symptoms vary not only in the same epizodtic 
but at different times to such a degree that it is impossible to refer to 
all of them. In some cases they suggest a general disorder. In 
others they are referable to certain parts or organs such as the mucosz 
of the digestive and respiratory tracts, the brain or integument. As 
a rule several organs are implicated. 
The initial symptoms such as depression, roughened condition of 
the coat, loss of appetite and elevation of temperature are suggestive 
of a general disturbance. 
In a large majority of cases, conjunctivitis is the primary ocular 
symptom. ‘Tears flow from the eyes and photophobia is present. 
The mucous membrane of the eyelids becomes conjested and a purul- 
*Krajewski, Mégnin, Laosson, and Babes and Starcovici, compute the period of 
incubation at 4to 7 days; Venuta, 4 to 6 days; Trasbot, 5 to 8 days; St.-Yves Menard, 
8 to 12days; Sewell, 4to 14days; Nocard and Leclainche, 12 to 15 days; and Hobday, 
3 to 4 days to 3 weeks. Jenner states that evidences of illness appear during the second 
week after exposure to infection. 
