Spatial analysis of long-term combined epidemic manifestations of some natural focal infectious diseases in the territory of the Astrakhan region was carried out using geographical information system. Suggested is the method to detect territories where these combined epidemic manifestations are stable and its high effectiveness and predictive value are demonstrated. On the basis of received data suggested are the measures to increase the effectiveness of epidemiologic surveillance for natural focal infectious diseases.

Presence of combined natural foci of plague, tularemia, Crimean-Congo hemorrhagic fever, West-Nile encephalitis, Astrakhan spotted fever in the North-West Precaspian region was substantiated. Influence of anthropogenic and climatic conditions in formation of combined natural foci of infectious diseases of bacterial, rickettsial and viral etiology was pointed out. Up-to-date potential epidemic danger of the territories under consideration was evaluated.

Based on the experience of the long-term epizootiologic survey in the natural foci of plague, determined were the principles of usage of the developed methodology of monitoring of the dangerous infectious diseases combined with plague. The methods of collection of the field material to identify the agents of different infections were suggested. Prospects of complex differentiation of territory according to the level of epidemic danger were considered. The tasks of further study of the areas, spatial and biocenotic structure of combined natural foci of plague and other dangerous infections were formulated.

Objective – risk-oriented assessment of the current epidemiological situation on West Nile fever in the Astrakhan Region.Materials and methods. Utilized were the data collected by the Astrakhan Plague Control Station, Rospotrebnadzor Administration in the Astrakhan Region, and A.M. Nichoga Regional Infectious Clinical Hospital. The key method of study was epidemiological analysis of West Nile fever incidence among the population of the Region during the period of 2000–2016. 145 case records were investigated.Results and discussion. Retrospective analysis provided for identification and featuring of the main categories of epidemiological risk of infection with West Nile fever in the Astrakhan Region in 2000–2016. It was established that men of 19 to 70 age range ( 82.1 %) are infected more often (95 out of 145 – 65 %). WNF infections in women occur among the same age group (75.8 %), and also among children aged below 6 years old (9.0 %). Analysis of the risk territories showed that the level of risk is high in one district, medium – in one district, low – in four districts, and very low – in six. When investigating the conditions of infection (risk factors) with WNF, it was determined that in the majority of cases (107 – 73.8 %) the risk factors were not specified. Out of those that were identified, one should pinpoint the bite of mosquito inside the households, basements, while fishing (16.3 %), as well as the bite, removal or squashing of a tick with unprotected hands (6.9 %). The period of the highest risk is from May to October with the maximum values of incidence in August (55.1 %).

Российский научно-исследовательский противочумный институт «Микроб», Саратов 2 центр гигиены и эпидемиологии в Саратовской области, Саратов, Россия epidemic actiVitY of modern anthropourgic plague foci and factors determining this actiVitY (BY the eXample of Vietnam) sludsky a. a. 1 , Kuznetsov a. a. 1 , matrosov a. n. 1 , Boiko a. V. 1 , Kouklev e. V. 1 , tarasov m. a. 2 1 russian research anti-plague institute «microbe», saratov 2 center of hygiene and epidemiology in the saratov region, saratov, russia