Abstract: | With a large collection of the strains of F. tularensis isolated it has been recently shown that cultures belonging to holarctica and mediaasiatica circulate in the endemic foci of the USSR. By their biological and genetic properties the natural strains of F. tularensis were homogeneous and represented type cultures of F. tularensis. Various ecological conditions in the natural environment did not change within the last 20 years the sensitivity of the tularemia microbe to the antibacterial drugs. |