Studies Upon Asiatic Cholera

Everyone who has written upon the subject of cholera has pointed out that however familiar we may be with respect to the characters of the pathogenic organism discovered by Koch in I883, with regard to its pathogenicity the single fact actually known is that the presence of this vibrio in the intestinal mucosa causes the disease. But why do the vibrios undergo modifications in the body? Why do they lose their virulence? Why do they disappear? Why does the patient recover? These questions have remained un-answered. There is the same obscurity with regard to the epidemiology of the disease, and there is no explanation for the sometimes bizarre progress of epidemics. Some towns and villages remain free of the disease despite the fact that infected persons are brought in, while in a neighboring town or village the arrival of a single cholera case is sufficient to start a violent epidemic. Similarly, no one has yet explained why an epidemic may terminate permanently, and often very suddenly, after having caused hundreds of thousands of deaths. Much has been published upon the subject of cholera, but although purely laboratory studies are numerous, very rare have been those studies made within the devastated regions at the bedside of the patient. Of what value can pure laboratory studies be in such a subject? None at all. When the bacteriologist has wished to study the characteristics of the cholera vibrio he has turned to old laboratory cultures, vibrios which have been maintained for years outside of their natural environment. He may be able to add a new culture medium to the innumerable ones which have already been described, and this may indeed be useful although there is no organism more readily cultivable. And what shall we say of the results obtained by those who have undertaken to study the pathogenesis of cholera by animal inoculation, by attempting to infect with old strains of the vibrio, guinea pigs and rabbits, animals which are completely refractory? A recent and voluminous work of San-