[A histologic study of Ceratophyllus consimilis Wagn. fleas infected by the agent of murine typhus (Salmonella typhimurium)].

Histological studies of C. consimilis infected with S. typhimurium have shown that the microbes are preserves along the whole extent of the alimentary canal, expecially in the midgut and pyloric portion. Bacteria are concentrated in the gastral cavity; in addition, they were found to penetrate the alimentary epithelium cells and pyloric valve tissue. The number of microbes and their distribution in the intestine undergo great variations that depends largely on the insects feeding rhythm. During bloodsucking a "lavenment" of the alimantary canal takes place; as a result, numerous microbes accumulated here are periodically excreted outside. The infection with Salmonella typhimurium is often accompanied by pathological changes in fleas tht is expressed in the destruction of the midgut epithelium and pyloric valve tissue.