BACILLUS SUISEPTICVS 227 



Salmon, Smith, Moore, Jensen, and Bang confirmed the early work 

 of Loeffler and Schiitz. The disease has been found in several Euro- 

 pean countries, and is quite widely spread throughout the United 

 States. 



Pathologic Lesions. In the most acute cases the changes found in 

 the dead animals are those of a typical hemorrhagic septicemia, with 

 petechial and ecchymotic hemorrhages into the skin, subcutaneous 

 fat, and the serous and mucous membranes. The kidneys, including 

 the subscapular tissue, the pelves, and even the parenchyma, very 

 frequently are the seat of blood extravasation. The membranes of 

 the brain are likewise frequently hemorrhagic; the lymph glands 

 show a condition of acute hemorrhagic inflammation. In cases which 

 have not taken the most acute course the lungs are generally found 

 involved. They show multiple areas of consolidation which are at 

 first dark brown red and later a lighter grayish red. The foci of 

 consolidation contain necrotic material, and in older cases the entire 

 lobe of a lung may have become changed into a mass of caseous 

 necrotic substance. The non-consolidated pulmonary tissue is edem- 

 atous, the pleura thickened, congested, and covered by a fibrinous 

 exudate. The pericardium may show similar changes, and the pleural 

 cavity may contain a varying amount of hemorrhagic seropurulent 

 fluid. The mucosa of the gastro-intestinal tract is swollen and hemor- 

 rhagic and sometimes covered by rather thin pseudomembranes, formed 

 by superficial necrotic cells. The spleen is not enlarged, the kidneys 

 are congested. According to Moore the pneumonia of swine plague 

 presents itself both as a lobar and as a lobular bronchopneumonia. 

 In the former the alveoli become filled with red and white blood cor- 

 puscles and fibrin. In chronic cases the animals are much emaciated, 

 and the lungs, peribronchial and mesenteric glands and tonsils contain 

 necrotic foci. 



Morphology and Staining Properties. In the most acute cases the 

 Bacillus suisepticus (also called Bacterium suicidum) is found in 

 great numbers in the blood and internal organs. In the less acute 

 cases it is found in the consolidated and necrotic foci in the lungs, 

 occasionally also in the blood. In the chronic cases the organisms 

 do not occur in the blood, but as necrotic foci in combination with 

 other bacteria, such as streptococci, staphylococci, Bacillus pyogenes 

 suis, Bacillus necrophorus, and others. The bacillus suisepticus is 

 one micron to a micron and a fraction long, 0.5 to 0.6 wide. It is 

 sometimes almost oval or round; at times it stains quite uniformly, 

 at other times in a bipolar manner. Longer bacilli occasionally stain 

 like the diphtheria bacillus, at both ends and in the centre. The 

 bacillus stains with the ordinary anilin stains, is Gram negative, not 

 motile, possesses no flagella, but a capsule can be demonstrated by 

 proper staining methods. The organism, like that of bubonic plague 

 in older lesions, is often of a swollen vacuolated type, stains only with 

 a peripheral ring, and then has the appearance of an empty shell. 



