In addition to the epidemic disease known as Asiatic cholera, there is a condition known as Cholera nostras. The researches of Koch have demonstrated the connection between Asiatic cholera and the comma bacillus. It is probable that cholera nostras and choleraic diarrhoea may be produced by microbes of allied, but not identical characters (see p. 357).

The phenomena of cholera are those of a very violent irritation of the mucous membrane of the intestine; the symptoms of cholera are largely those of a general poisoning of the system. During life the disease is characterized by the discharge of extremely fluid stools which, from the intermixture of finely divided material, give the characteristic Rice-water appearance. Sometimes a patient dies without the bowels having been moved, and in that case the latter are found distended with the rice-water discharge. The flakes which give their character to the rice-water evacuations are not so much composed of desquamated epithelium as of little masses of mucus containing leucocytes. After death the epithelium may be found loose in the intestine, but this appears to be from post-mortem maceration, for, if examined sufficiently early, the epithelium is found apparently normal.

It is obvious that there is here an enormous transudation from the vessels of the intestine. The chemical character of the discharge, however, seems to indicate that it is not a mere inflammatory exudation from the vessels, but rather a secretion from the glands. Its specific gravity is low, 1006 to 1013. There is very little albumen present, and the discharge contains a ferment which has the power of converting starch into sugar.

The most marked post-mortem appearance is a remarkably rosy injection of the vessels in all the coats of the intestine, so that a red appearance is visible even in the serous coat whenever the body is opened. The mucous membrane is swollen and the closed follicles prominent. Occasionally there is a decidedly inflammatory condition present, which may be even of a dysenteric character.

The condition of the other parts of the body is directly referable to the enormous withdrawal of water from the blood. The blood itself is thick, dark, and imperfectly coagulated. The skin, serous membranes, and all the soft tissues are shrunk, dry, and parchment-like. The membranes of the brain are frequently injected. The kidneys present the characters of a slight parenchymatous inflammation.