Application of GIS Technologies for Determination of Boundaries and Area of Epizootic Regions within Natural Plague Foci

Spatial indicators of epizooties in natural plague foci are used for justified planning and carrying out measures on epidemiological welfare provision for the population residing in enzootic territories. Plague affected regions are identified by real geographical coordinates of epizootic sites. Objective of the study is to develop numerical methods for determination of boundaries and area of epizootic regions according to the results of epizootiological monitoring. Materials and methods. Utilized are the digital maps of the natural plague foci, the data on epizootic points, and computer software. Results and conclusions. Buffer zones in the form of circumference of 5 km radius were established around each epizootic point with the help of computer application “ArcGIS 10.x” as a counterpart of circular extrapolation method. Resultant epizootic region over a certain season was generated by several overlapping circumferences.Evaluated were the area and extension of the region, as well as the presence of epidemiologically significant objects within its bonds.Actual positioning of the region, visualized on the focus map, is used for specified task assignment as regards carrying out of various preventive measures in this or that part of the area

Blood-Sucking Fly <I>Icosta ardeae</I> – Its Distribution and Probable Role in Circulation of West-Nile FeverVirus

Communication comprises materials on distribution of blood-sucking fly, Icosta ardeae, in the territory of the Russian Federation and bordering states. Based on the analysis of literature data, collection assets, and personal investigations assumed has been the fact that this species is more widely spread in the local fauna than it was anticipated earlier. The fly parasitizes on the birds of 11 species, orders - ciconiiformes (storks), shore (wading) birds, Gruiformes, and fowl-like birds (Galliformes). More often I. ardeae is seen among bitterns – 43 % of the findings, abundance index –5,9. Therewith, put forward is the suggestion concerning the role of the species and other Hippoboscidae in the process of persistence and distribution of West-Nile fever virus. Studies of this group of insects can be of use for identification of mechanisms that benefit natural foci extension and development as regards various infectious diseases

To 110th Anniversary of the Federal Public Health Institution Astrakhan Plague Control Station

Presented is a historical essay on the work of one of the oldest Russian anti-plague institutions - Astrakhan Plague Control Station. Noted is the fact that specialists of this institution made a substantial contribution to the development of the theory of plague natural focality and other contagious infections, as well as to the provision for and implementation of measures for epidemiological surveillance and prophylaxis of plague and other particularly dangerous infectious diseases in the territory of the North-West Caspian sea region

Boundary Changes of Natural Plague Foci in the North-Western Pre-Caspian

Objective of the study is to specify present-day locations and sizes of natural plague foci in the North-Western Pre-Caspian.Materials and methods. Based on the results of field and office mapping of Pre-Caspian sandy and North-Western steppe plague foci, conducted in 2013–2014, designed have been electronic maps of the sectors, situated in the periphery of the foci.Results and conclusions. Detected has been marked reduction in sizes of natural foci owing to plowing of arid pastures. Over a significant distance, new natural focal boundaries are represented by linear elements of hydrography. Wherein such elements are absent, sector frames, in which evidence of enzooty remains, are accepted as formalized external boundaries. The process of deep and irreversible anthropogenic transformation of landscapes has resulted in the reduction of enzootic as regards plague territories: the steppe focus area has decreased by 22 %, being 51152 sq. km, the sandy one – by 13 %, amounting to 62510 sq. km. Farming on the extensive territories as a means of radical alterations of the landscapes has made the lands unsuitable for habitation of the little souslik, midday and tamarisk gerbils, which is an evidence of a complete loss of plague enzooty factors in the territory. The survey of actual position and sizes of natural plague foci within the rigid bonds, plotted on topographic maps and easily identifiable afield, provides for substantiated planning and complex prophylactic plague-control measures. Novel spatial parameters of the natural foci are suggested for the inclusion into official regulatory-methodological documents, guiding performance of epidemiological surveillance over plague

MODIFICATIONS TO THE BOUNDARIES OF THE NATURAL PLAGUE FOCI IN THE VOLGA-URAL INTERFLUVE

Objective of the study is to locate the present-day sites and sizes of the natural plague foci in the Volga-Ural Interfluve. Materials and methods. According to the results of the field and office mapping, 2015 in the Volga-Ural steppe and sandy plague foci, designed have been electronic maps of the sectors situated in the periphery. Results and conclusions. During the past 3–4 decades significant decrease in plague enzooties in the territory of the Volga-Ural Interfluve has been observed. It occurs due to the plowing and melioration of the grazing lands. It is established that the southern and south-western outskirts of enzootic territories have natural boundaries represented with the linear elements of hydrography, and the eastern ones are the state border of the Russian Federation and the Republic of Kazakhstan. At sites where suitable linear elements of the landscape are absent (up north and west) the frames of the sectors, where evidence of enzooty is retained, are used as the formal external boundaries. Widespread plowing of semi-desert area made the territories in the eastern part of the Volgograd Region inadequate for small souslik habitation, which marks the loss of plague enzooty features. This fact in its turn led to the reduction of steppe focus acreage by 30 %, the coverage being currently 20873 km2 . Configuration of the sandy focus changed little, if at all, and amounts to 8625 km2 . Registering of the actual position and sizes of natural plague foci within the strictly set boundaries put on topographic maps provides for targeted planning and complex prophylactic anti-plague measures. New spatial indicators of natural plague foci are formalized in official normative-methodological documents regulating epidemiological surveillance over plague

PROSPECTS OF STANDARDIZATION AND SYSTEMATIZATION OF THE POINTS FOR EPIZOOTIOLOGICAL SURVEILLANCE OF NATURAL PLAGUE FOCI

Currently existent procedure for free positioning and registration of sites for field sample collection results in chaotic concentration of visualized on electronic map icons of surveyed areas, which obstructs spatial analysis of the results on monitoring in a given period of time.Objective of the study is to develop the system of standardization, positioning, and numbering of the points for epizootiological surveillance as part of monitoring over natural plague foci.Materials and methods. Topographical maps, epizootiological mapping data and their analysis.Results and conclusions. Optimum size of the icons corresponding to sites of epizootiological surveillance (SES) is 10 seconds in latitude and 15 seconds in longitude. One sector comprises 900 standard SESs. Put forward system of optimization is able to significantly ease epizootiological and epidemiological mapping, enhance visualization of monitoring data, as well as expand the capacities and improve the quality of spatial and retrospective analysis of epizootic activity of natural plague foci

Volga-Ural Sandy Plague Focus Differentiation against Epizootic Manifestations by Means of Circular Extrapolation

Displayed are the results of study of the Volga-Ural sandy plague focus spatial structure. Constructed has been the map of the area with long-lasting persistent epizootic manifestations, monitored throughout the whole period from 1926 to 2012, using method of circular extrapolation of plague microbe detection points. Epizootic area mapping and map adjustment have been carried out automatically with the help of ArcGIS-10 software. The map displays the dislocation of plague focus activity nuclei and zones of short-term epizootic process registration; identified have been their quantitative parameters. Cartographic model of plague-focal territory differentiation against epizootic manifestation index is designed for validated planning of epidemiological surveillance activities and further studies of plague enzootics issues. The data obtained can be used for epidemiological zoning of territories as regards plague

Natural Mega-Focus of Yersinia pestis Main Subspecies, Antique Biovar, Phylogenetic Line 4.ANT in Gorny Altai

Objective of this study was to investigate the areal of Yersinia pestis strains of antique biovar, main subspecies, phylogenetic line 4.ANT, as well as to establish the borders and spatial structure of mega-focus in the territory of Gorny Altai. Materials and methods. Complex comprehensive analysis of the properties in Yersinia pestis strains of the main subspecies, circulating in Gorny Altai has been conducted. 33 out of them, isolated predominantly in 2012–2017 have been sequenced. Whole genome SNP analysis and search of marker SNPs was performed using Wombac 2.0 software package. Tree diagram was built applying Maximum Likelihood algorithm, using PhyML 3.1 software on the basis of HKY85 model. Results and conclusions. Based on the results of whole genome SNPs analysis of 33 endemic strains and creation of the tree diagram of Y. pestis strains, the presence of natural mega-focus of Y. pestis belonging to the main subspecies, antique biovar, phylogenetic line 4.ANT has been substantiated. Epizootic manifestations on multiple local areas, characterized by persistent autonomous nature of plague manifestations, are registered on an annual basis. Within the boundaries of the areal of Yersinia pestis main subspecies, antique biovar, phylogenetic line 4.ANT, existence of joint natural foci of Yersinia pestis belonging to non-main subspecies ssp. altaica and ulegeica is established. Location of natural foci of the main and non-main subspecies of Yersinia pestis in different altitudinal belts of the Altai Mountains Range on the whole provides for observed multi-host and multi-vector feature of epizootic manifestations. For the first time ever, the data on the areal of the main subspecies of plague microbe are used for setting the boundaries of its natural focus

Epidemiological Activity of Hemorrhagic Fever with Renal Syndrome Foci in the Territory of the Russian Federation in 2013–2017 and Forecast for 2018

Assessed has been epidemiological situation on hemorrhagic fever with renal syndrome (HFRS) in the territory of the Russian Federation in 2013–2017. Forecast for 2018 has been substantiated. 39238 HFRS cases in 59 administrative territories of 8 Federal Districts were registered over the analyzed period. The highest morbidity rates were reported in the Privolzhsky Federal District, where 82.9 % of the total case number occurred. Given has been the forecast for the retention of adverse situation on HFRS in 2018 in the territory of Privolzhsky and Central Federal Districts. In order to reduce the HFRS incidence among the population it is necessary to increase the scale and scope of monitoring investigations and strengthen their epidemiological aspect, as well as substantiate, plan and carry out broad range of measures of non-specific prophylaxis