Analysis of the epizootical situation in the North-West Mongolia and bordering regions of Russia has revealed the fact that plague agent of the main ssp., for the first time ever isolated in the Altai mountain natural plague focus in 2012, is imported from Serkh-Munkh-Khairkhan, which stands approximately 240 km away from it on the straight. It has been demonstrated that possibility of Yersinia pestis ssp. pestis transfer into the territory of Gorny Altai via slow natural migration of infected rodents, lagomorphs and their ectoparasites, as well as transmission by birds or terrestrial varmints in the mountainous environment over that large distance even within the period of several decades, is extremely...