RESUMO
In the Irkutsk suburbs (a relatively southern area of the Irkutsk Region of the nosoarea of a natural tick-borne encephalitis focus), Ixodes persulcatus imagoes begin its activity in the first 10 days of April and usually finishes it in September. In 1996-2006, there was a trend for an increase in the number of the tick's bites in human beings, as well as three-year cycles of fluctuation of this index. In the Bratsk suburbs (a relatively northern area), the imago becomes active only in late April and the last sticking cases usually take place in late August. In 1996-2006, there was no increase in the number of tick attacks of the population, but the cycle period of this index being longer than in the Irkutsk suburbs. It has been earlier recommended that two all-round antitick treatments using cipermitrine-based compounds should be made in the area of epidemiologically significant objects in the Irkutsk suburbs in late April and in the third 10 days of May. It is sufficient to perform one treatment in the Bratsk suburbs in the third 10 days of May.
