CHOLERA VIBRIO 569 
an acute peritonitis, from which the animal grackially sinks into a state 
of coma; the temperature falls, and death may intervene, with or with- 
out preliminar}' convulsions. At autopsy, the peritoneum is reddened, 
the peritoneal surface of the intestine is markedly congested, and there 
are small ecchymoses. There is some increase in peritoneal fluid, 
which may contain vibrios. The animal, however, does not as a rule 
die from peritonitis. The organisms after injection pass into the 
general circulation, producing a transient vibrionemia, and wander in 
large numbers to the gastro-intestinal canal where they produce a severe 
inflammation; the probable cause of death is gastro-enteritis, which, 
if somewhat delayed, leads to a postmortem intestinal picture resemb- 
ling human cholera.^ Subcutaneous injections of like amounts of 
culture may or may not result fatally. The organisms, however, as 
Theobald Smith pointed out many years ago, tend to migrate to the 
intestinal tract, suggesting that some chemotactic influence attracts 
them there. Intravenous injection, particularly in young rabbits, may 
lead to lesions in the intestinal tract, suggesting those characteristic of 
cholera in man, but as a rule far less severe. The organisms may also 
be found in the intestinal contents and gall-bladder following intra- 
venous injection. 
Feeding experiments in the ordinary way are not successful. Koch- 
succeeded in infecting young guinea-pigs with cholera vibrios by first 
administering sodium carbonate by mouth to neutralize the gastric 
acidity, then introducing by mouth 10 cc. of a broth culture of the 
vibrios directly into the stomach with a catheter. The animals died 
usually in about two days with symptoms, and particularly intestinal 
lesions which resembled those of cholera in man. There were diarrhea, 
bloody rice-water stools with abundant organisms in them, collapse 
and death. Issaeff and Kolle^ made similar experiments in young 
rabbits, and Wiener^ has successfully infected kittens in the same 
way. Pottevin and Nicolle^ have induced cholera in monkeys with 
cholera vibrios. The animals are given first a large dose of sodium 
sulphate, then a dose of bicarbonate of soda, after an initial fasting 
period of twenty-four hours. Greig,^ using a similar procedure, has 
induced a fatal disease in rabbits which resembles cholera very defin- 
itely both with reference to gross symptoms and histological lesions. 
Cholera-like vibrios, however, may give somewhat similar results, 
although larger amounts of culture must be administered.^ 
Human. — (a) ExjxHmental Evidence of Disease. — In man infection 
takes place usually by ingestion of food or water contaminated with 
cholera vibrios. The first accidental laboratory infection is probably 
that mentioned by Koch** of a doctor who accidentally swallowed part 
1 Castellani: Compt. rend. Acad. Sci., 1919, 168, 578. 
2 Deutsch. med. Wchnschr., 1885, 11, No. 37a, 5, 6. 
3 Ztschr. f. Hyg., 1894, 18, 17. ' Centralbl. f. Bakteriol., 1890, 19, 205. 
6 Bull. Soc. de path. Exotique, 191.3, 6, No. 7. 
6 Indian Jour. Med. Research, 1917, 5, No. 1. 
' Ibid., 1917, 5, No. 2: 1916, 3, No. 5. 
8 Deutsch. med. Wchnschr., 1885, 11, No. .37a, 7. 
