A Comparative Study of the Efficacy of the Various Agar-Dye-Mediums Recommended for the Isolation of Typhoid and Dysentery Bacilli from Feces

Abstract

This immediately suggested the possibility of improving the existing methods for the detection and isolation of B. typhosus and B. dysenteriae or paradysenteriae. As the result of a few preliminary tests, however, it was quite evident that only a careful comparative study of the existing differential mediums would supply sufficient information to permit of reliable conclusions. The ever increasing reports on elaborate mediums, for the detection of typhoid and dysentery bacilli in stools, show clearly that the problem of this particular technic is not yet solved. And inasmuch as the control of enteric fever and of dysentery will largely depend on the diagnosis and bacteriologic supervision of potential carriers, the knowledge and the application of reliable methods which regularly permit the isolation of the infecting organisms is absolutely necessary even when their numbers are very few. In fact, in experimental work with typhoid carriers in rabbits and other animals, we have encountered difficulties which were traceable to the unreliability of the solid culture mediums used for the detection of typhoid baccilli in the dejecta. The progress of our studies on carriers and dysentery infections depended largely on the development of one or two methods which rendered the isolation of the offending organisms a comparatively simple process. It is for these reasons that we have retested a large number of recently described methods. In presenting the results, we wish to