SWINE FEVER 373 



pneumonia is commonly present, whence he termed the disease 

 " pneumo -enteritis." McFadyean, however, from his own experi- 

 ence and that of the Board of Agriculture, considers pneumonia 

 very infrequent. The ulcers occur mainly in the caecum and colon, 

 and are due to a well-defined circular necrosis involving the whole 

 thickness of the mucous membrane and occasionally extending to 

 the wall of the bowel. A diffuse diphtheroid lesion also occurs, due 

 to a superficial necrosis with deposition of a thin layer of fibrinous 

 exudate on the surface of the mucous membrane. All gradations 

 are found between the well-defined circular necrosis and the diffuse 

 diphtheroid lesion. 



An organism constantly present is a member of the para- typhoid 

 sub-group of the Gartner group (B. suipestifer oisuicholerce, apparently 

 identical with B. aertryck), but it seems to be a terminal infection 

 and not the true ctiological agent, as the blood and tissues filtered 

 through a porcelain filter are still infective i.e. the organism is 

 probably ultra-microscopic. Some confusion exists in the nomen- 

 clature of the disease. Swine fever is the British, and hog cholera 

 the American, name. In addition, a disease of swine was formally 

 described under the designation "swine plague" ("Schweine- 

 seuche," Schiitz). This clinically much resembles swine fever, but 

 pneumonia is a prominent lesion, and a non-motile, stumpy, 

 bi-polar staining bacillus belonging to the group of the haemorrhagic 

 septicaemia bacilli is present (see under "Chicken Cholera"). 

 This is now regarded as a secondary infection and the disease as 

 being really swine fever. The B. suipestifer is apparently identical 

 with the B. ictero'ides of Sanarelli. (See also Chap. XIX.) 



Although the lesions are very similar, swine fever has nothing to 

 do with typhoid fever of man, nor with ulcerative colitis. 



Other organisms belonging to the Gartner group are : 



1. The Danysz bacillus, used as a virus for exterminating rats 

 (the Danysz virus). 



2. The B. icteroides of Sanarelli, supposed by him to be the cause 

 of yellow fever, but apparently identical with the B. suipestifer (see 

 " Yellow Fever," Chap. XIX). 



3. The B. typhi murium of Loffler, used as a virus for exterminating 

 mice. 



4. The B. psittacosis of Nocard, causing an infective disease of 

 parrots and transmissible to man (bird-fanciers, etc.), in whom it 

 produces a severe and often fatal broncho-pneumonia. 



5. Summer diarrhoea. Morgan x concluded that the summer or 



Ri * Brit. Med. Journ., 1906, vol. i, pp. 908 and 1131 ; ibid. 1907, 

 vol. i, p. 16. 



