Presented is the review of literarary and authors` data on the ways of emergence of Vibrio cholerae eltor strains, atypical as regards their virulence properties. The enhancement of virulence of cholera eltor agent at present was shown to be associated with acquisition of Vibrio cholerae cholerae CTXφ prophage as a result of horizontal gene transfer. Another possible way of formation of strains with higher virulence is described - alteration of cholera toxin resident genes regulation due to rearrangement of CTXφ prophage genome by the introduced transposon. Also considered are evidences on origination of ctxA^- tcpA⁺ strains and their enhanced viability in aquatic environment as compared with isogenic toxinogenic clones. Presented are the prospects of the development of new PCR test for detection of cholera eltor agent with altered virulence in monitoring investigations.

This review is devoted to the analysis of the main achievements of the Russian and foreign scientists in the sphere of development of immunodiagnostic methods for detection of Francisella tularensis and specific serum antibodies. The most important problems concerning perspectives of constructing of the modern effective test-systems for tularemia immunodiagnostics are discussed.

As a result of transitions of the Meriones genus gerbils and fleas phoresy the parasitic contact nets are formed in their settlements to provide the effective settling of ectoparasites and spreading of plague etiological agent. The contact net covers all the territory occupied by the rodent settlings that do not have spatial disconnection.

The role of the background species of mouse-like rodents in the preservation of arboviral infections in the semi-desert zone of Saratov Zavolzhie was studied. Determined were the indices of their number in the near-water and anthropogenic biotopes, and arboviral infection rate in some species. Substantiated was high potential epidemic danger of the intrazonal biotopes as centers of formation of associated natural foci of arboviral infections.

The analysis of sickness rate carried out from 1984 to 2007 revealed the complicated epidemiologic situation with plague in the world, especially during the period of 1991-2003. The most strained situation formed in Africa. During the analyzed period the tendency to increase the plague incidence in the world - 2.4-fold, in Africa - 4.1-fold and to decrease in America - 11.1-fold and in Asia - 1.7-fold was observed. Uneven character of plague cases distribution in the world was determined: 80.1 % of cases were registered in Africa, 14.1 % - in Asia and 5.8 % - in America. From 1990 to 2006 10 local outbreaks of pneumonic plague were registered in the world: 4 - in Asia, 5 - in Africa and 1 - in America.

Harmonization of the national normative methodical basis of the Russian Federation in the sphere of the sanitary protection of the territory with the IHR (2005) will simultaneously signify its harmonization with the requirements of the World Trade Organization Agreements and will not lead to the contradiction with them. Requirements contained in the normative documents referring to the sphere of the sanitary protection are priority ones regarding to the regulations of the World Trade Organization documents as they touch upon public health protection. The standard duration of the procedure of the sanitary and quarantine control of cargo transport, goods and cargos should be foreseen in the methodical documents.

The modern boundaries of distribution of tamarisk gerbil - Meriones Tamariscinus (Pallas, 1773) were determined in the territory of the republic of Kalmykia. Shown was the role of irrigation and watering of the land in the expansion of its natural habitat to the north and north-west. Epizootiologic and epidemiologic consequences of tamarisk gerbil settling in the territory of Pre-Caspian North-Western steppe natural focus of plague were considered. The tendency of formation of the integrated plague natural focus of the gerbil type in the North-Western Pre-Caspian region and Ciscaucasia was confirmed.

The constructed avirulent biplasmid Vibrio cholerae strain KM182 producing cholera toxin B subunit and Escherichia coli colonization factor CFA/1 (providing for antitoxic and anti-colonization immunity formation, correspondently) was demonstrated to protect immunized model laboratory animals from experimental cholera caused by the virulent Vibrio cholerae O139 strain. The optimal doses for immunization and challenging were determined.

Determined was complete nucleotide sequence of rhaS gene, the regulatory gene of rha locus of chromosome in Yersinia pestis strains of main and minor subspecies and in Y. pseudotuberculosis of I-III serovariants. The presence of significant and inessential nucleotide replacements in rhaS gene was shown. Evidently, these replacements are the cause of different abilities for rhamnose fermentation in the strains of plague etiological agent (main and minor subspecies) and those of pseudotuberculosis agent.

The comparative assessment of fluoroquinolones efficacy in experimental tularemia treatment was carried out. Sparfloxacin, pefloxacin and moxifloxacin were shown to be highly effective when treating this disease in test animals.

It was stated that the reaction of APUD-system cells reflects immunologic and adaptive-compensatory processes in the organisms of guinea-pigs subcutaneously inoculated by Y. pestis EV vaccine strain. Shown was the dynamics of changing of activity and quantity of apudocytes in immunocompetent organs in different periods of immunogenesis after anti-plague vaccination of biomodels. Implementation of quantitative assessment of content and function of apudocytes in lymphoid organs and adrenals during vaccination process allows characterizing the adaptive-compensatory reactions in biomodel organism and makes it possible to comparatively analyze reactogenicity and safety of vaccines developed against this infection on the stages of their preclinical trials.

Arabinoganactane isolated from Siberian larch (Larix sibirica) and its iron and cobalt nanobiocomposites were selected as immunomodulators to elucidate the possibility of intensification of specific immunity against plague. Comparative morphometric analysis of immune system organs of white mice inoculated with live plague vaccine (LPV) and its combination with immunomodulators was performed. Experimental data indicate that arabinogalactane and its nanobiocomposites used in combination with LPV increase immunocytopoetic function of immune system organs to larger extent than LPV.

Biotechnological scheme for F(ab')₂-fragments of anti-rabies immunoglobulin production using immobilized pepsin was developed. Optimal ways for immobilized pepsin production were determined, conditions for fermentative hydrolysis of anti-rabies immunoglobulin were sorted out. Protective properties of F(ab')₂-fragments of anti-rabies immunoglobulin produced by means of this method were assessed.

Effects of Y. pestis EV antigenic complexes upon the functional activity of the phagocytic cells of guinea pig and white mice were assayed to demonstrate that the preparation constructed on the basis of the F1 antigen, Y. pestis EV membrane fraction and the Siberian larch arabinogalactane (AG) used as an immunomodulator, was able to increase the functional activities of the phagocytic system in test animals (guinea pigs), enhancing the adhesive and absorptive activity of the peritoneal macrophages and the intensity of active oxygen and nitrate monoxide production, as well as stimulating the activity of myeloperoxidase and the synthesis of non-enzyme cationic polymorphonuclear leucocytes. The antigenic complex prepared on the basis of the F1 antigen, Y. pestis EV membrane fraction and AG, was also shown to exert a stimulating effect on cytokine-inducing function of white-mouse macrophages expressed in the increased production of IL-1, IL-6 and FNO-α cytokines.

The review presents the results of application of the programs of discrete and stationary wavelet-analysis for filtration of object image from noise and for the increase of its resolution capability in electronic and probe microscopy.

Assessed were possibilities of identification and differentiation of glanders and melioidosis etiological agents by means of PCR method using different nucleotide sequences of the pathogenic Burkholderia. Primers perspective for inclusion in the test-system assigned for detection of glangers and melioidosis etiological agents DNA in environmental samples and biological materials were selected.

Reviewed in the work are the results of comparative studies of experimental plague infection development in test animals after their aerogenic or subcutaneous challenge with virulent Y. pestis strains (pFra⁺, pCad⁺, pPst⁺, pgm⁺) and their isogenic variants, lacking pFra and/or pPst. Any virulent strain and its isogenic variants were shown to produce both pulmonary and bubonic-septicemic forms of plague depending on the infection transmission route and the dose of the pathogen. The test animals infected via aerogenic and subcutaneous routes with isogenic Y. pestis deprived of their pPst or pPst/pFra plasmids and grown in Hottinger agar at 28 C developed a lingering infection.

The landscape-ecologic zoning of HFRS natural foci was carried out. Three zones and 13 natural foci were ear-marked in the territory of the Republic of Mordovia. Places where people can be infected and the indices of HFRS immunity of the community in some natural foci were determined. As a result of epizootiologic investigation it was stated that 4.1 % of rodents were infected by Hantavirus. Continuous monitoring of HFRS natural foci is necessary to carry out modern preliminary prophylactics of this disease.