It is generally admitted that the discovery of the cholera bacillus has given the profession a certainty in the diagnosis of sporadic cases of cholera, which we could not possess without it. Indeed, the importance of the search for the cholera bacillus is emphasized by the latest report by Guttmann from the Berlin cholera hospital, who proved by the detection of the specific germ, that apparently inoffensive cases of diarrhœa may really be mild attacks of genuine cholera. While it is evident that bacteriological advance has thus increased materially the efficacy of prophylactic measures, it cannot be claimed that it has as yet aided the therapeutics of cholera. Reports from various sources, however, indicate that the problem of protective vaccination against cholera is nearly solved.
The first efforts to immunize animals against infection with cholera bacilli, or against poisoning by their products, were reported by Brieger, Kitasato and Wassermann. Theoretical