Competitive effects of intestinal microflora on Vibrio cholerae in gnotobiotic mice.

The coexistence of Vibrio cholerae and several intestinal bacteria was determined in gnotobiotic mice. The bacteria tested included a Bacteroides sp, Clostridium difficile, Clostridium perfringens type A, 2 separate isolates of Escherichia coli, 2 different Lactobacilli, 2 separate isolates of Proteus mirabilis, Pseudomonas maltophilia, and Streptococcus faecalis. Each species of bacteria became established and was recovered repeatedly from the stools during the studies. No single strain or species was found that would eliminate V cholerae from these mice within 2 wk. Not until a combination of E coli, P mirabilis, and S faecalis was present in the mice did V cholerae disappear from the stools in 14 da.