[Detection of persistent resistance to antibacterial drugs in various strains of Francisella tularensis].

Under natural conditions, the Francisella tularensis strains AE-261 and P-13864 capable of forming the persist type of resistance to antibacterial drugs and being the cause of the infection in laboratory animals not responding to monotherapy with antibiotics were detectable. The antibioticograms of strains AE-261 and P-13864 under the in vitro conditions did not differ from those of the other studied strains responding to the antibiotic therapy. The observed phenomenon could be associated with individual peculiarities of the strains and their phenotypic variation in the host. Combinations of aminoglycoside antibiotics (streptomycin, gentamicin and amikacin) with rifampicin were shown to be highly active in the treatment of general forms of the infection due to such strains. The combined therapy of tularemia was also considered promising because of its high efficacy when the treatment was started at late periods as well as because unlike the monotherapy with the aminoglycoside antibiotics it provided complete elimination of the pathogen from the host.