The viability of B. typhosus in alkaline bile in vivo

In as much as Nichols suggests the use of alkaline therapy for the purpose of eradicating B. typhosus within the gall bladder of human carriers of the disease, the following observations are pertinent.

While carrying out a series of tests with experimental rabbit carriers of typhoid, it was noted in a certain instance that the hydrogen ion concentration of the bile was different from that supposed to characterize the normal animal. This indication was followed with other animals as opportunity presented itself. P_H determinations were made on the bile of uninfected animals as materials appeared. The method followed was that of Clark 1 and Lubs with the comparator block introduced into the system. Readings were made as soon after the death of the animal by exsanguination as possible, generally within three quarters of an hour. In order that contact with the air and consequent loss of dissolved gases might be reduced to a minimum, the bile was kept either within the closed syringe with which it had been aspirated or was placed within a small bore agglutination tube. All animals had been fed regularly on a ration of rolled barley and succulent grass.

No animal was classed as a carrier unless it had been inoculated with B. iyfihosus at least two weeks previously since it was felt that time sufficient for physiological adjustment should be given. This period is arbitrary but is conservative since between one and two weeks are required before the weight curve of the animal commences to ascend. Rabbit carriers were prepared according to the method of Gay 1 and Claypole 2 which in this series yielded IOO per cent. efficiency. No bile was classed as having been taken from a positive carrier unless subsequently B. typhosus was isolated from it and confirmation made by agglutination.