[Data on a study of a natural focus of sandfly fever in Sevastopol during 1945-1988].

Sandfly [correction of Mosquito-borne] fever in Sevastopol was of a marked season character (June-September), with maximum cases registered in August. The morbidity curve corresponded to the sandfly [correction of mosquito] number curve, lagging behind it because of the incubation period. Since 1947 DDT and hexachlorane, having a lasting effect (40-50 days), have been widely used for sandfly [correction of mosquito] control. This was accompanied by intensive improvement of the living conditions in the city, regular sanitation and deratization. As a result of the above measures sandfly [correction of mosquito-borne] fever has not been registered in the city since 1954. The number of sandflies [correction of mosquitoes] reduced drastically, their species composition has changed: in 1959 sandflies [correction of mosquitoes] were found in 5.4% of the houses examined and in 1988, in 0.16% of houses. Since 1958 only 2 (Phlebotomus papatasii Scop and Ph. major Ann.) out of the former 7 species have been caught. Each species strives for self-preservation. Therefore, epidemiological survey of the former foci and sandfly-control [correction of antimosquito] measures are to be performed annually not to permit recovery of sandfly [correction of mosquito] population and repeated epidemics of sandfly [correction of mosquito-borne] fever.