Studies on experimental shigellosis. I. Shigella infections of normal mice.

Experimental Shigella flexneri 3 infections produced in normal mice have been described. The passage of viable Shigella through the stomach of orally infected animals, and the persistence of the organisms in the intestine for periods of 5 to 7 days, with an increase in bacterial numbers, indicated that true infection was produced. Blood culture studies showed that a Shigella bacteriemia occurred after either oral or parenteral administration of Shigella to normal mice. Mice infected orally revealed mild, but consistent pathological changes, including mesenteric hemorrhage, liver and spleen hypertrophy, and occasional diarrhea.