PATHOGENIC SPIRILLA. 569 



pigs. The researches of Dunbar (1894) indicate that Pfeiffer's test 

 is not so reliable as he supposed ; and also that phosphorescence can- 

 not be relied upon for distinguishing similar water bacteria from 

 genuine cholera vibrios. Rumpel has reported the fact that two un- 

 doubted cultures of the cholera spirillum, from different sources, after 

 being passed through pigeons and cultivated for some time in arti- 

 ficial media, showed phosphorescence. One of these cultures was ob- 

 tained originally from the discharges of Dr. Oergel, who was a vic- 

 tim to cholera from laboratory infection (case reported by Reincke, in 

 the Deutsche medicinisclie Woclienschrift, No. 41, 1894). Another 

 case of supposed laboratory infection, in which recovery occurred, is 

 reported by Lazarus, in the Berliner medicinische Wochenschrift, 

 1893, page 1,241. 



That cholera vibrios may be present in the alimentary canal of 

 healthy individuals without giving rise to any symptoms of ill-health 

 appears to be demonstrated. In support of this conclusion we quote 

 as follows from a recent paper by Abel and Claussen : 



" In Wehlau (East Prussia), in the autumn of 1894, seven cases of 

 cholera occurred about the same time. The members of the family 

 were at once isolated and their faeces examined almost daily. Of 

 especial interest were seventeen individuals who belonged to families 

 in which three fatal cases occurred. Of these seventeen persons, who 

 were not sick at all or only had for a brief time a diarrhoea, thirteen 

 had cholera vibrios in their discharges for a considerable time. As 

 the table shows, many of these comma bacilli were not found in dis- 

 charges every day, but were obtained again after being absent" (in 

 the cultures) " for a day or two." 



Abel and Claussen (1895), as a result of very extended experi- 

 ments, arrive at the conclusion that cholera vibrios in faaces as a rule 

 do not survive longer than twenty days, and often cannot be ob- 

 tained after two or three days; exceptionally they were obtained in 

 cultures at the end of thirty days Karlinsky and Dunbar have re- 

 ported finding them at the end of fifty-two days and four months. 

 Karlinsky (1895) has also reported that upon woollen and linen goods, 

 cotton batting and wool, which were soaked in the discharges of 

 cholera patients and preserved from drying by being wrapped in 

 waxed paper, the cholera vibrio retained its vitality for from twelve 

 to two hundred and seventeen days. 



The researches of Kasansky (1895) show that the cholera spiril- 

 lum is not destroyed by alow temperature (30 C.) and that it 

 even resists repeated freezing and thawing three or four times. 



Behring and Ransom (1895) as a result of an extended experi- 

 mental research, arrive at the conclusion that cholera cultures from 

 which the bacteria have been removed have specific toxic properties, 

 40 



