INFLUENCE OF INTERMITTENT 98 PERCENT OXYGEN AND 380 MM. HG TOTAL PRESSURE ON SUSCEPTIBILITY TO TULAREMIA.

Mice were conditioned by exposure three times per week for 2 weeks to an atmosphere of 97 to 99 oxygen at 380 mm. Hg total pressure for 2 or 8 hours per exposure. They were then infected intraperitoneally with Pasteurella tularensis and either exposed daily to the same test conditions or kept at ground level under normal conditions. The results indicate that the length of the exposure period 2 or 8 hours did not influence host susceptibility however, increased susceptibility was observed in animals exposed to the test conditions before infection regardless of whether or not they were further exposed subsequent to challenge. Conditioned animals receiving additional exposure were not more susceptible than those retained under normal conditions after infection. Author