The Incidence of B. Dysenteriae in the Normal Individual. 20

Abstract

In recent years mild epidemics and a few isolated cases of bacillary dysentery have been reported from various sections of the Southern States (Boyd, 1 Silverman and Harris, 2 Davidson 3 ). However, these publications have dealt primarily with the active disease. There is a notable lack of information concerning the “carrier” or the occurrence of the specific bacilli of dysentery in the apparently healthy individual of this section of the country. It was, therefore, thought that a systematic study of the stool from healthy persons might prove of interest.

Fifty healthy individuals, with no history of dysentery or intestinal disturbances, were selected from various sections of New Orleans. Fresh specimens of feces, without previous purgation, were obtained through a proctoscope, and cultured immediately upon suitable media for the recovery of dysentery bacilli in accordance with the methods originally suggested by Duval. 4 Only one stool specimen was cultured in each instance. A large number of plate colonies were transferred and studied biologically. Identification of B. dysenteriae was made by means of the cultural (sugars) and serological methods. It is possible that repeated bacteriological examinations might have influenced the results; however, as all cases were handled alike, it was not deemed necessary to repeat the stool examinations.

Specimens of blood were also obtained from each case, and a routine microscopic and macroscopic agglutination test carried out with stock cultures of B. dysenteriae, namely, Flexner, Shiga, Hiss “Y” and Duval's 5 lactose fermenter, which was reported by him in 1904 and later confirmed by Sonne 6 in those instances where dysentery bacilli were isolated from the stools of the normal individuals, they were tested for agglutination by the serum of the homologous case and immune serum from the experimental animal.