Tularaemia is a disease caused by the facultative intracellular bacterium Francisella tularensis. Vaccination resulting in protective immunity is induced by live vaccine only. Such vaccination can be performed by scarification utilizing the live vaccine strain of F. tularensis (F. tularensis LVS), which results in good but not complete protection. Humoral as well as cell-mediated immunity are induced by vaccination and it has been shown that cell-mediated immunity is a prerequisite for protection. Since the live vaccine strain is attenuated and the genetic background of attenuation is unknown it is important to consider process parameters so that the immunogenicity of the vaccine is preserved.