THE GROUP OF THE DYSENTERY BACILLI 315 



ferentiated from the typhoid bacillus by cultural reactions, Bacillus 

 alcaligenes forming neither acid nor gas in dextrose, lactose, saccharose, 

 or mannite. It does not liquefy gelatin, and it produces a permanent 

 alkalinity in milk. The differential cultural reactions are shown in 

 the table (page 316). 



Dissemination and Prophylaxis. Nothing is known of the method of 

 dissemination of Bacillus alcaligenes. It appears to be an organism 

 whose portal of entry is the gastro-intestinal tract. Carriers have 

 never been satisfactorily demonstrated. Prophylaxis is precisely the 

 same as that for other intestinal organisms. 



THE GROUP OF THE DYSENTERY BACILLI. 



The term dysentery as it is used in the clinical way includes at 

 least two entirely distinct entities: amebic dysentery, a semi-acute 

 or chronic infection caused by an ameba, which is usually restricted 

 to the tropics and subtropics; and an acute type caused by members 

 of the dysentery bacillus group, more frequently encountered in 

 temperate zones. The latter type not uncommonly assumes epidemic 

 proportions, but occurs sporadically as well. Japan has suffered greatly 

 in the past from the ravages of bacillary dysentery. Ogata and 

 Eldridge 1 state that 1,136,067 cases with 257,289 deaths occurred in 

 that country during the period between 1878 and 1899 inclusive. 

 The mortality, which varied markedly from year to year, averaged 

 22.6 per cent, of all cases. The disease appears to be rare in England, 

 but it has been reported in Germany. 2 The Atlantic seacoast cities 

 of the United States have experienced epidemics of the disease, but 

 the inland cities appear to have been relatively free from it. During 

 inter-epidemic years mild, atypical, sporadic cases and moderate 

 numbers of bacilli carriers (both of the Shiga and Flexner types of 

 organisms) have been discovered. 3 



The most virulent of the dysentery bacilli was isolated and described 

 by Shiga 4 during the great epidemic of 1897 to 1898 in Japan. Flexner 5 

 recovered an organism which he believed was identical with the Shiga 

 bacillus from cases of dysentery in the Philippines. Later studies of 

 this organism by Martini and Lentz 6 revealed specific differences in 



1 Quoted in Public Health Reports, 1900, xv, 1. 



2 Kruse, Deut. med. Wchnschr., 1900, vol. xxvi. 



3 Kendall, Boston Med. and Surg. Jour., 1913, clxix, 754; May 20, 1915. 



4 Cent. f. Bakt., 1898, xxiii, 599; xxiv, 817, 870, 913. 

 B Ibid., 1900, xxviii, 625. 



6 Zeit. f. Hyg., 1902, xli, 540. 



