Abstract
Summary and Conclusions 1. Once a body louse, P. humanus humanus, became infected with Bact. tularense, both the louse and its feces harbored the tularemia organism for varying periods ranging up to 53 days, depending upon the environmental conditions. 2. Temperature was the greatest single contributing factor to longevity of the organism in the louse or louse feces, with lower temperature causing greater survival. 3. Humidity showed a tendency toward playing a significant part in survival, especially at higher temperatures; the lower the humidity, the longer was the survival. 4. No statistically significant difference was noted concerning longevity of Bact. tularense and the louse substrate. Louse feces, however, at low humidity, gave remarkable survival.