Summing up, in our study BALB/c mice infected with HPAI, strain A/duck/Tuva/01/06, appeared to be able to produce the innate immune response, which culminated to the development of shock and subsequent multiple organ failure. The main characteristics of our model are comparable to the previously described fatal cases of H5N1 influenza in humans [10, 11] . Proposed model reflects lesions not only same organs but also mediating levels of some (IFN-γ, IL-6, IL-10) cytokines in terminal conditions.