Infections associated with the suction of ticks, the so-called tick fever, refer to natural focal diseases and are seasonal in nature. Currently, it is known that ticks are carriers of a number of viruses, bacteria, spirochetes that cause diseases in humans. The diagnosis for a signifi cant part of these infections remains unverifi ed. A common clinical symptom for all infections caused by ticks is fever, which is part of the general infectious (febrile-toxic) syndrome, which, in turn, may have features inherent in one or another infection. This review provides clinical characteristics of tick-caused infections registered in Russia: febrile tick-born encephalitis, ixodic tick-born borreliosis, babesiasis, ehrlichiosis, tick-born rickettsial disease, hemorrhagic fevers, tularemia, bartonellosis. The basic criteria for the diff erential diagnosis of general infectious syndrome as the main manifestation of the onset of these diseases are presented. It is shown that due to the similarity of symptoms, especially in mixed-type foci, specifi c laboratory diagnostics should be regarded as determinative in diagnosis