AGGLUTINATION. 459 



curative ; the discharges rapidly decrease in number 

 and the course of the disease is shortened. In the 

 Rockefeller Institute for Medical Research anti- 

 dysentery serum proved of no distinct value. 



The agglutination reaction with the serum of 

 patients shows great variability. It is sometimes 

 absent in spite of the presence of bacilli in the 

 stools,, and often disappears rapidly during con- 

 valescence (in two weeks occasionally). It is rarely 

 as high as in typhoid. In infantile diarrheas ag- 

 glutinins appear at about the end of the first week 

 of illness (Duval and Bassett). Evidently mild 

 cases in which the course of the disease is from 

 four to eight days may not be recognized by means 

 of the agglutination reaction before the period of 

 convalescence. In chronic cases the agglutinating 

 power may persist for three or four months. No 

 reaction was obtained with the typhoid bacillus. 

 Kruse considers the reaction diagnostic when it 

 occurs in a dilution of 1/50; Pfuhl, 1/30. Strong 

 co-agglutinins for other organisms, i. e., above 

 1/50, have not been observed (Lentz). The tests 

 should always be performed with both the "Shiga" 

 and "Flexner" types, as the two have not identical 

 agglutinable properties, and either organism may 

 be the cause in a given instance. The absence of 

 the reaction does not exclude a dysenteric infec- 

 tion positively. Bacteriologic examination of the 

 stools is important, often necessary, for early diag- 

 nosis. 



IV. MEAT POISONING BY BACILLUS ENTERITIDIS. 



Botulism as a special form of meat poison- 

 ing and the occasional production of paratyphoid 

 by infected meats, have been mentioned. In 

 addition to these, more or less extensive epidemics, 



