610 PATHOGENIC SPIRILLA. 
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 feces 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 diarrhcea, 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 feeces 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, 
and cause symptoms similar to those which result from the intro- 
duction into guinea-pigs of the living bacteria; that from these fil- 
tered cultures a solid substance can be obtained having the same 
toxic properties, and that from susceptible animals which have been 
treated with this toxic substance a serum can be obtained which is 
active not only against the cholera poison, but against the cholera 
vibrio. These results support those previously reached by other 
bacteriologists and lead to the hope that a specific treatment of the 
disease may be successfully employed. The results obtained by 
Haffkine in India are favorable to the view that his method of prophy- 
laxis, by the subcutaneous injection of virulent cholera cultures, has 
a real value. 
