388 TYPHOID FEVEE 



has been unable to find evidence of the dysentery bacillus being 

 present. He has, however, very frequently (in 63 per cent. 

 of the cases examined) found in the stools and intestine a 

 bacillus (" Morgan's No. 1 bacillus ") which is a motile Gram- 

 negative organism producing acid and slight gas formation in 

 glucose, lsevulose, and galactose, and no change in lactose, 

 mannite, dulcite, maltose, dextrin, cane-sugar, inulin, amygdalin, 

 salicin, arabinose, raffinose, sorbite, or erythrite ; it further 

 causes indol formation, and in litmus milk slowly originates an 

 alkaline reaction. It produces diarrhoea and death in young 

 rabbits, rats, and monkeys when these animals are fed on 

 cultures. It is thus possible that in this bacillus we have 

 still another cause of the disease. Morgan has found that in 

 diarrhoea cases the lactose fermenters, so characteristic of normal 

 faeces, are relatively less numerous and tend to be replaced by 

 non-fermenters of lactose. His bacillus has been found in a 

 certain proportion of normal children, but this especially during 

 the epidemic season ; it has also been found in flies. 



Isolation and Differentiation of Coli-Typhoid 

 Bacilli by Culture. 



The existence of a large group of intestinal diseases with 

 similar clinical features caused by closely allied bacteria makes 

 the differentiation of these affections and of the causal bacteria 

 a difficult problem. The difficulty is increased where, as in 

 recent war conditions, several of these diseases may be 

 simultaneously prevalent, each on a considerable scale. The 

 best solution of the bacteriological problem is found in the 

 isolation of the organisms from the stools or blood of the 

 patient, but here often the best methods may fail to yield 

 cultures, especially when, as has often been the case, the 

 individual does not come under observation till the acute phase 

 of the disease has passed. Moreover, cases occur where more 

 than one member of the pathogenic intestinal bacteria may be. 

 present. The isolation method should, however, invariably be 

 attempted. 



Post mortem, organisms may be isolated from the solid 

 organs, especially from the spleen, from the mesenteric glands, 

 from the heart-blood, especially in typhoid, paratyphoid, and 

 Gaertner infections — to a much less extent in dysentery. The 

 intestine, of course, may also be a source of culture. 



During life the bacilli may be obtained in culture in the 

 following ways : — 



