124 SWINE ERYSIPELAS 



§ 110. Geographical Distribution. Swine erysipelas 

 is an infectious disease that occurs enzootically and in epi- 

 zootics in most of the countries of Europe. It was formerly 

 restricted in Bavaria to the districts along the Danube, and 

 was entirely unknown in southern Bavaria (Kitt). It is 

 stated that the disease tends to become enzootic chiefly in 

 valleys and low-lying plains which have slow-flowing streams 

 and heavy, damp, cla}- soil ; and that sandy and granite soils 

 are comparatively free from it. It occurs chiefly during the 

 months of July, August and September, although it appears 

 sporadically during the winter m.onths. It has not been 

 described from the United States. 



§111. Etiology. Loeffler and Schiitz 



'(^ '^^/"v:- pointed out in 1885 that swine erysipelas 



was caused by a very slender bacterium 



{Bad. erysipelatis suis) i to 2/< long and 



0.3 to 0.4// broad, straight or slightly 



curved, ends not rounded and in cultures 



Fig. 20. Bacter- often appearing in filaments. It is very 



inm of swine ery- closel}^ related to the bacterium of mouse 



sipelas, showing septicemia described by Koch in 1878. In 



free organisms ^^^ ^y\i^x^ the bacterium of mouse 



and also th&jr 

 presence ru ithin septicemia is quite common, swine erysipe- 



the cells. las prevails. There is much uncertainty 



concerning the relationship of the bacter- 

 ium of mouse septicemia to that of this disease. Smith has 

 suggested that possibly the bacterium which has been found 

 in this country may gain virulence sufficient to produce epi- 

 zootics, if such is not already the case. It is exceedingly 

 important that careful search be made for this organism in the 

 outbreaks among swine where the nature of the disease is not 

 clearly determined. House mice and pigeons are susceptible 

 to the bacteria of swine erysipelas ; guinea pigs and fowls are 

 immune. Rabbits suffer from erysipelatous swellings when 

 inoculated subcutaneously in the ear. The bacterium of 

 swine erysipelas is to be differentiated from that of mouse 

 .septicemia. 



