[Factors that determine the possibility of tick-borne encephalitis infection. 3. The probability of human contact with an infected vector in the central taiga forests of Khabarovsk Territory].

Contacts with Ixodes persulcatus Sch. and the carriers' infestation with encephalitis virus have been studied for many years in middle taiga forests of the Khabarovsk Territory. The results of the studies have been compared. The risk of contacts with ticks invaded with varying virus doses has been assessed. It has been established that clinical forms of the disease develop upon bites of highly infected ticks. The number of such ticks in the natural focus is an important index of its potential danger. This must be taken into consideration as the most important factor of possible infection and used as a real index in the modelling of an epidemic process.