The article examines the interregional corruption contagiousness that appears in the unions which are differentiated with respect to economic integration levels. The results of the different researches show that the corruption is able to spread as the virus between neighbor countries. But the approach to research of such phenomenon has not been developed yet. The corruption contagiousness is interpreted as the Markov process therefore. The article defines the corruption contagiousness speed and the mechanism of statistical estimation of this parameter. Also it contains the estimation of the speed in different integration unions.