Udovikov А. I. RussiaSaratovRussian Research Anti-Plague Institute "Microbe", 46, Universitetskaya Str., Saratov, 410005, Russiaстарший научный со- трудник лаборатории эпизоотологического мониторингадоктор биологический наукudovikovau@mail.ru Author's articles Assessment of Epizootiological Value of Fleas (Insecta, Siphonaptera) in the Phenomenon of Seasonal Plague Manifestations in the Steppe Natural Plague Foci of Souslik Type in the Northern, North-Western Pre-Caspian and Pre-Caucasus Regions