Climate and Transformation of Ecosystems by the Example of Natural Plague Foci of South-East of Russia

Shown was the influence of modern day warming and some other factors on natural plague foci of the European South-East of Russia. Analyzed were the basic mechanisms of transformation of biocenotic structure of natural foci complexes. It was shown that the tendency of gradual change of dominant carriers species would be preserved due to further warming of climate. As a result, the expansion of polyhostal natural foci of plague of semidesert type would be continued

Role of Mosquitoes, <I>Culex</I> <I>pipiens</I> Complex, in West Nile Fever Virus Persistence in Urbanized Biocoenoses of Saratov

. In wiggler samples as well as in imago ones detected are WNF virus markers, which indicate the possibility of transovarial and trans-phase transmission of virus into mosquito populations, habitant in urbanized biocoenoses. It is substantiated that Culex pipiens female mosquitoes, which reproduce autogenically, provide for the persistence of the virus within the inter-epidemic period. Therewith there is a possibility of sustained, epidemically-active WNF micro-foci to be formed in the residential area landscapes, and this issue should be given proper consideration when performing assessment of the risks associated with urban population exposure to the infection

Conditions for Virus Circulation and Premises for Natural West Nile Fever Foci Formation in the Territory of the Saratov Region

Local climate change (rise of mean temperatures and amount of precipitation, prolongation of frost-free season) triggers further distribution, and increase in numbers of animals – carriers and vectors of West Nile fever virus in the territory of the Saratov region. Based on the results of ecological-epizootiological monitoring (2006–2012) traced out have been the species composition, abundance dynamics, and character of distribution of birds habitant in aquatic and anthropogenic complexes, mosquitoes and Ixodidae ticks. Investigated are possible causes of West Nile fever nosoarea expansion, related to ecology of migrating birds wintering in Africa. Persistent circulation of the virus in intra-zonal inundated biocoenosis facilitates formation of secondary natural foci of West Nile fever and factors into epidemic complications as regards this particularly dangerous vector-borne infection. On the basis of analytical data concerning hydrographic network density, fauna structure, population numbers of birds and mosquitoes – potential carriers and vectors of WNF, epizootiological and epidemiological surveillance, designed has been expectation-driven forecasting map chart which illustrates possibility of sustainable WNF foci formation in various territories of the Saratov region

Distribution and Abundance of Ticks and Fleas, Infectious Diseases Vectors, in the Semi-Desert Zone of Saratov Trans-Volga Region

Many-years observations demonstrate that six species of the ticks inhabit semi-desert zone of Saratov Trans-Volga Region. Nine flea species are registered at small mammalians in the near-water biotopes. The dominating ectoparasite species can be of significance at present as dangerous infectious diseases vectors. They are 2 ticks species and 3 flea species. Epizootiologic monitoring to be carried out is associated with control of abundance of ectoparasite species conventional for this territory, and with detection of new species possessing condition to inhabit it