Therapeutic efficacy of bicyclomycin for shigellosis experimentally induced in rhesus monkeys.

The efficacy of orally given bicyclomycin on shigellosis was studied in rhesus monkeys infected with Shigella fIexneri 2a. All the animals developed lethal infection after rectal inoculation of the virulent strain 5503. Bicyclomycin and the kanamycin control were given orally at daily dosage of 40 mg;kg for a period of 5 days beginning 24 hours after the inoculation. Bicyclomycin compared favorably with kanamvcin in respect to 1) the time required for termination of bloody mucous feces, restoration of normal feces, and disappearance of Shigella bacilli from feces and 2) the absence of the bacilli from intestinal tissues at autopsy. This experiment was preceded by a fundamental study, which revealed satisfactory activity of bicyclomycin against various Shigella species (MIC: 6.2525 mcg/ml) and good stability and excretion in feces. These data demonstrate the therapeutic efficacy of bicyclomycin in intestinal infections.