Discussion on the prevention of enteric fever / opened by George Vivian Poore and continued by W.T. Gairdner [and others].

  • George Vivian Poore
Date:
1898
Catalogue details

Licence: Public Domain Mark

Credit: Discussion on the prevention of enteric fever / opened by George Vivian Poore and continued by W.T. Gairdner [and others]. Source: Wellcome Collection.

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    whicli are nevertheless no true typhoid bacilli. In order to exclude such bacilli it is necessary to test the cultures in glucose media^ and expose them to the body tempera- ture (liquid media in some form of fermentation tube, or shake cultures in media stiffened with agar) ; under these circumstances bacilli such as Gartner^s are definitely ex- cluded, for they are able to form gas at 37° C, although they are unable to do so at 20^ 0. Of other media which are of importance in discriminating the typhoid bacillus I will mention the neutral litmus whey of Petruschky, and the litmus media of Capaldi and Proskauer. The former serves a double purpose : on the one hand it shows the amount of acid which the bacillus is able to produce in the presence of lactose; and on the other, since it is practically almost free from proteids, it demonstrates the scanty growth of the typhoid bacillus in such media. In reference to the question of sero-diagnosis, I think we may lay it down absolutely that what is known as ^' Widal's test is absolutely worthless. By this I mean the technique which was published by Widal some months after Gruber had brought the question forward at Wiesbaden. Widal's test, then, consists in investi- gating the action of the serum of typhoid fever patients when diluted only to the extent of 1 in 10 upon a typhoid culture ; I think that it is quite proved that such low dilutions give no satisfactory evidence, unless nega- tive. If, however, proper dilutions are made (Gruber^s test)—the necessity for which was emphasised by Gruber himself in April, 1896 Yerhandlungen des Congresses fiir innere Mediciu,^ 1896)—more satisfactory evidence of reaction is obtainable (the following dilutions form a useful series for practical clinical purposes, viz. 1 : 20, 1 : 50, 1 : 100, ] : 200, 1 : 500, and 1 : 1000). In any case, un- less a given serum reacts strongly in high dilution, the evidence given only amounts to a probability. It would appear that some observers have endeavoured to differen- tiate bacilli by means of their reaction towards sera ob- tained from typhoid fever patients. This is an extremely