| Abstract: | Strains of the plague microbe, antigen complete and defective by fraction I and mouse toxin had the same in vitro susceptibility to ofloxacin (MIC 0.08 mg/L). The drug was superior in its activity to pefloxacin and especially nalidixic acid. In the experiments with albino mice (prophylaxis, 5 days) the ofloxacin efficacy was lower when the infection was due to the plague microbe strains deprived of the ability to produce fraction I and mouse toxin, evident from a statistically significant increase of the drug ED50 and a decrease of the animal survival percentage. When used in the doses corresponding to the human average daily doses, ofloxacin provided effective animal protection (80 to 100 per cent survival) after the prophylaxis for 7 days and the treatment of the plague infection irrespective of the strains, complete or antigen changed. However, when the infection is due to the antigen changed strain, ofloxacin should be used in the maximum daily doses at least for 7 days. |
