[Effect of the irrigation and reclamation transformation of the Karshi Steppe on burrow sandflies of the genus Phlebotomus--vectors of the causative agent of zoonotic cutaneous leishmaniasis].

Studies of land irrigation effect on Phlebotomus sandflies, carriers of Leishmania major (a zoonotic cutaneous leishmaniasis causative agent)--were performed for 15 field work periods, from 1967 to 1981, at 18 sites in various natural areas of the Karshi Steppe (Uzbek SSR). Over 43500 sandfly specimen were caught and identified. Regularities in sandfly number changes, first of all, that of Ph. papatasi, after irrigation were determined, with respect to various proximity of great gerbils' settlements, where sandflies breed in the irrigated fields. Well-drained sites situated higher than irrigated fields are practically unaffected by irrigation, sandflies number and specific composition being practically unchanged. At the sites situated either on the same level with irrigated fields or 3-5 m lower the number of sandflies changes usually in 2 stages: 1) short-term increase in Ph. papatasi number at the very beginning of the irrigation period; 2) formation of stably high or low Phlebotomus numbers due to stabilization of hydrothermal regime in the holes of great gerbils.