506 THE CHOLERA GROUP 



administering sodium carbonate by mouth to neutralize the gastric 

 acidity, then introducing by mouth 10 c.c. 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 1 made similar experiments in young 

 rabbits, and Wiener 2 has successfully infected kittens in the same 

 way. 



Human. (a) Experimental 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 3 of a doctor who accidentally swallowed part 

 of a culture and contracted the disease. Hasterlik, 4 Metchnikoff, 5 

 Reners, 6 Kolle 7 and Voges 8 have also reported laboratory infections 

 of man with cholera vibrios which resulted in typical disease in each 

 instance, thus establishing beyond reasonable doubt the etiological 

 relation of the cholera vibrio to the disease cholera. 



(b) Natural Infection. The incubation period of the naturally 

 acquired disease cholera may be very short; the patient may be 

 infected and die within twelve hours, so-called cholera sicca. 9 Ordi- 

 narily the incubation period is from one to two days. 10 



The important clinical symptoms are extremely painful cramps, 

 great withdrawal of water from the tissues, due to the violent diarrhea, 

 resulting in shriveling of the skin of the extremities and increased 

 viscosity of the blood. The urine after the first day is scanty in 

 amount, the stools are very fluid, "rice-water stools," and there is 

 profound collapse. The most noteworthy lesions postmortem are 

 in the small intestine, particularly the lower half. The mucosa is 

 swollen and congested particularly about Peyer's patches; the contents 

 of the intestinal tract are fluid and contain shreds of mucus. There 

 is parenchymatous degeneration of the liver, kidneys and spleen. 

 The intestinal contents swarm with vibrios. In the markedly chronic 

 cases there may be extensive necrosis and serofibrinous exudation on 

 the surface of the intestinal mucosa. 



1 Ztschr. f. Hyg., 1894, xviii, 17. 2 Centralbl. f. Bakt., 1896, xix, 205. 



3 Deutsch. med. Wchnschr., 1885, No. 37a, 7. 4 Wien. klin. Wchnschr., 1893, 167. 

 5 Ann. Inst. Past., 1893, No. 7. Deutsch. med. Wchnschr., 1894, 52. 



' Ztschr. f. Hyg., 1894, xviii, 17. 8 Centralbl. f. Bakt., 1895, xviii, 629. 



9 Metchnikoff, Ann. Inst. Past., 1893, 581. 

 10 Banti, Lo Sperimentale, 1887. Giinther, Deutsch. med. Wchnschr., 1892, 841. 



