406 RINDERPEST 
of transmitting the disease to susceptible ones in close contact with 
them only during the febrile period and most certainly during the 
time the temperature was declining. ‘The infection was not trans- 
mitted during the convalescent stage. The virus in the urine, diluted 
with water and sprinkled on grass, survived not longer than 36 hours. 
They did not find any recovered cases that transmitted the virus. 
Persons may carry the virus on their shoes, clothing and farm 
implements. Even small animals such as cats and rats, which fre- 
quent barns and stables, have been looked upon as carriers of the 
infection. The hides of animals dead of the disease may transmit 
the infection. The virus is destroyed, according to Hutcheon, by 
complete desiccation. Kraiewsky found that the virus was destroyed 
in hides soaked in corrosive sublimate 1-1000 for 24 hours, or in 2.4° 
per cent. carbolic acid for the same time. 
Boynton found that the large water leech (Hirudo Boyntoni Whar- 
ton) can retain the virus of rinderpest alive in its body for at least 
twenty-five days in a virulent condition. The large leech held the 
virus alive much longer than the smaller ones. His studies of the 
leech in connection with the transmission of rinderpest have shown 
very conclusively that the leech is a factor in the propagation and 
spread of rinderpest. 
The period of incubation varies from 3 to 6 days. In animals 
inoculated with virulent blood it is from 60 to 90 hours. Boynton 
found that the period of incubation in cattle infected with virus from 
a leech was 10 days. 
Symptoms. The first symptom of rinderpest is a rise of tempera- 
ture* (105° F. to 106° F.) which continues near that point with but 
slight variations until near the end when in fatal cases it drops to sub- 
normal and in those that recover it gradually returns to normal. At 
first the animal is more lively than normal, showing evidence of being 
under a nervous strain. This is stated by Boynton to be more 
prevalent in cattle than in carabaos. About the third day the 
nervousness begins to disappear, the hair is roughened, the ears lop 
forward and the conjunctiva is congested. The eyes become sensitive 
to light. Usually there is a profuse discharge of tears from the inner 
canthus. Later this may become sero-purulent. The pulse is small, 
beating from 120 to 160 per minute. There is debility, decrease in 
*Boynton reports a case of rinderpest without a rise of temperature. 
