SUMMER DIARRHCEA 387 



Doerr, using his toxin from the Shiga-Kruse strain, produced 

 in horses an antitoxic serum having protective and curative 

 properties in animals. This serum has been used in^a number 

 of cases of bacillary dysentery in man with good results. Shiga 

 ,produced a polyvalent serum by injecting horses with agar 

 cultures of different strains, and states that it has been used 

 in Japan with good results in doses of 20-50 c.c. Further 

 observation is necessary as to the therapeutic effects, in cases 

 associated with the Flexner strain, of an antitoxin produced by 

 the Shiga strain. 



It will be seen that the evidence furnished is practically 

 conclusive as to the causal relationship between this bacillus and 

 one form of dysentery, a form, moreover, which is both wide- 

 spread and embraces a large proportion of cases of the disease ; 

 and especially of importance is the fact that observations made 

 independently in different countries have yielded practically 

 identical results on this point. 



Bacillus Dysenteric {Ogata). — Ogata obtained this bacillus in an 

 extensive epidemic in Japan in which no amoebae were present. He 

 found in sections of the affected tissues enormous numbers of small 

 bacilli of about the same thickness as the tubercle bacillus, but very much 

 shorter. These bacilli were sometimes found in a practically pure 

 condition. They were actively motile, and could be stained by Gram's 

 method. He also obtained pure cultures from various cases and tested 

 their pathogenic effects. They grew well on gelatin, at the ordinary 

 temperature producing liquefaction, the growth somewhat resembling 

 that of the cholera spirillum. By injection into cats and guinea-pigs, as 

 well as by feeding them, this organism was found to have distinct 

 pathogenic effects ; these were chiefly confined to the large intestine, 

 hemorrhagic inflammation and ulceration being produced. It still 

 remains to be determined whether this organism has a causal relationship 

 to one variety of dysentery. 



Summer Diarrhma. 



As has been already stated, the bacillus of dysentery,, the 

 b. coli, and the b. enteritidis sporogenes have been found 

 associated with epidemics of this disease. This indicates that 

 the condition may be originated by a variety of organisms, and 

 it is further probable that the clinical features in different 

 epidemics vary. This is to a certain extent illustrated by the 

 condition of the stools. In Britain these are usually green, 

 watery, slimy, and putrid, without blood or mucus, but in many 

 outbreaks in America blood and mucus are present. The 

 multiple origin of the disease has been illustrated by the work of 

 Morgan, who, in a careful investigation of the disease in Britain, 



