574 THE CHOLERA GROUP 
practically unaltered virulence at least twenty-four hours after their 
ingestion from feces, in the alimentary canal of flies (IMusca domes- 
tica and IMusca vomitaria). At the end of three days, however, they 
had practically disappeared. Those in contact with the dejecta of 
cholera patients, particularly doctors, nurses, and especially laun- 
dresses, are quite likely to contract the disease. The sacred rivers of 
India, the Ganges and the Jumna, are regarded by many as the home 
of the cholera vibrio, and it has been accepted in the past that drinking 
the water of these rivers by pilgrims who visited them in large num- 
bers yearly has been responsible to a large degree for the spreading of 
the disease, particularly in India. Hankin^ has made the astonishing 
statement that the waters of these rivers kill cholera vibrios in two 
to four hours, it being surmised that some soluble acid substance is the 
bactericidal agent. It has been stated that the waters of the Ganges 
contain active bacteriophage, which is responsible for the freedom of 
the water from cholera \ibrios.- The same statement is made about the 
Jumna River water. This observation, if corroborated, would dis- 
credit the spreading of cholera by pilgrims who bathe in the sacred 
rivers. 
Cholera Carriers.— The observations of Greig,^ who found cholera 
vibrios in the gall-bladders of 81 out of 271 cholera cadavers, and of 
Kulescha,'^ who described pathological changes in the gall-bladder 
and biliary passages caused by cholera vibrios, have attracted atten- 
tion to the importance of cholera carriers in the spreading of the 
disease. Zeidler^ found cholera organisms in the feces of a patient 
ninety-three days after convalescence, suggesting that these carriers 
might be of hygienic concern for months after recovery. ZlatorgorofP^ 
and others have made similar observations. Even healthy individuals 
who are in contact with cholera patients may have cholera organisms 
in their feces without symptoms. It must be remembered in this 
connection, however, that curAed l)acilli morphologically like cholera 
organisms, but not giving specific serum reactions, are not uncommon 
in the feces of healthy people. Generally speaking, cholera carriers 
are somewhat less likely to occiu- than typhoid carriers. 
Isolation of Cholera from Water.— The simplest method of isolating 
cholera vibrios from water is to prepare a sterile stock solution con- 
taining 10 per cent of peptone and 5 per cent of salt; to every 100 cc. 
of water to be examined 10 cc. of this stock solution are added, which 
practically converts the suspected water into a culture medium. The 
isolation then is carried out by the Schottelius method described above. 
The initial culture being the water itself, successively inoculating 
Dunham's tubes from the surface growth obtained in the water cul- 
' Ann. Inst. Pasteur, 1896, 10, 175, 511. 
- d'Herelle, F. : Bacteriophage, 1922, Trans. l)y Smith, p. 15. 
3 Indian Jour. Med. Research, 1913-1914, 1, 44, 50. 
^ Centralbl. f. Bakteriol., orig., 1909, 50, 417. 
■=• Ibid., orig., 1911, 58, 14. 
« Ibid., orig., 1911, 58, 14. 
