[The preliminary results of an ecological epidemiological study of Lyme disease in western Siberia].

Studies of Ixodes persulcatus ticks in Omsk, Kurgan, and Novosibirsk regions revealed natural foci of Lyme's disease. Vector infection rate varied from 21 to 23.5% in the Omsk region, from 30 to 52.9% in the Kurgan region, and from 15 to 58.3% in the Novosibirsk region. Serologic screening of inpatients hospitalized during the epidemic season of 1991 with suspected tick-borne encephalitis and Lyme's disease confirmed the latter condition in 10.8% of the examinees in the Omsk and in 10% in the Kurgan regions. These data indicate the presence of active natural foci of Lyme's disease on the examined territories in west Siberia.