SWINE PLAGUE 49 
Smith described swine plague as an independent disease, although 
it was often associated with hog cholera in the same animal. In 
Europe, Schiitz, Jensen, Bang, and Preisz established its independent 
nature. On account of its frequent association with hog cholera, it 
was thought by some to be a secondary infection only. Several out- 
breaks were studied which indicated that it was an epizodtic disease. 
It was differentiated from cholera by the lesions and bacteriological 
examination only. The discovery of the filterable virus of hog 
cholera has thrown doubt upon the conclusions of the earlier study of 
epizootic swine plague. The consensus of opinion seems to be that 
swine plague is a sporadic disease which rarely if ever occurs in epizo- 
6tic form. Certain lesions, such as petechial hemorrhages in the 
kidney, found in pigs dead from the septicemic form of swine plague 
are now known to be quite characteristic of hog cholera. For that 
reason, lesions that were formerly supposed to be due to Bact. suisep- 
ticum may have been caused by the filterable virus of hog cholera. 
The lesions resulting from, or peculiar to, Bact. suisepticum infection 
must be more definitely determined from future investigations. 
Geographical distribution. Swine plague occurs more or less fre- 
quently in every state in the Union. It is quite widely distributed in 
Europe. It does not appear to 
be restricted to any country. 
Etiology. Swine plague is 
caused by a non-motile, elon- 
gated, oval bacterium first de- 
scribed by Leeffler in 1885. 
Hueppe proposed the name Bac- 
terium septicemiae hemorrhagicae 
for this organism. Migula called 
it Bacterium suisepticum. 
Hutyra has found a filterable 
virus in the blood and other 
Fic. 4, BACTERIUM SUISEPTICUM FROM A parts of pigs suffering with 
a “GLASS PREPARATION OF A RABBITS Cohweineseuche. The possibility 
of a mixed infection in this case 
is not excluded. Other European observers have reported similar 
findings. 
Bacterium suisepticum and its closely related varieties attacking 
other animals have not been systematically studied and classified. 
