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The review presents the materials on the use of mobile laboratories, developed in the Russian Federation, in the framework of four main areas: monitoring of territories to identify the circulation of pathogens of natural-focal infectious diseases; monitoring of territories during the exacerbation of the epizootic situation; participation in the elimination of outbreaks of infectious diseases; monitoring of territories to control and predict the epidemiological and epizootiologic situation in preparation for mass events. The tactical and technical characteristics and the procedure for organizing the operation of the mobile laboratory for monitoring and diagnostics mounted on the platform of the KamAZ chassis are considered. A distinctive feature of the laboratory from the existing Russian and foreign counterparts is the availability of the necessary conditions for conducting research using bacteriological analysis, rapid and accelerated diagnostic methods, and performing a full cycle of works – from the preparatory stage to the destruction of infected material. Hightech equipment allows the realization of two research schemes: the first – bacteriological analysis alongside the PCR, which ensures high reliability of the results; the second – conducting the PCR at the first stage, and when identifying genetic markers of the pathogen – performing bacteriological analysis of positive samples in order to isolate the culture of the pathogen and identify it subsequently. The second scheme will reduce the volume of bacteriological studies; make changes in the tactics of epizootiological survey. Tests of the mobile laboratory have demonstrated the effectiveness of its use in the epizootiological examination of natural plague foci, including cross-border ones. Owing to the use of a mobile laboratory in the Gorno-Altaisk high-mountain natural focus of plague, a new epizootic site was identified, located in a remote area, used by the population as a summer pasture for grazing domestic animals. The use of mobile laboratories will strengthen the laboratory base of institutions that monitor particularly dangerous, natural-focal and other dangerous infectious diseases; will help to bring the advanced diagnostic technologies directly to the natural focus, reduce the risk of epidemic complications due to plague and other particularly dangerous infections in cross-border natural foci.

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 %).

At present, the search for biomarkers, which indicate the presence of tense antiplague immunity, is continuing. The aim of the study was to determine the parameters of cellular and humoral immunity in persons vaccinated with the plague vaccine according to epidemiological indications and to characterize the correlation interrelations between them in the dynamics of the antiplague response formation. Blood samples from 114 people living in the territory of the Pre-Caspian sandy natural plague foci were investigated. Using commercial kits, the production of cytokines IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-18, IFNγ, TNFα (Vector-Best, Russia) IL-17A (eBioscience, Austria), immunoglobulins IgG, IgM, IgA (Vector-Best, Russia) was determined on the enzyme immunoassay analyzer LAZURIT (Dynex Technologies, США). Blood leukocyte immunophenotyping was carried out using f luorochrome-labeled monoclonal antibodies Cyto-Stat CD45-FITC, CD4-PE, CD8-ECD, CD3-PC5 (Beckman Coulter, США) on the CyAn ADP DakoCytomation f low cytometer (Denmark). Obtained data analysis revealed a number of differences in the production of detectable cytokines (TNFα, IL-1β, IL-2, IL-4, IL-6, IL-17) between groups of vaccinated and first-vaccinated people. However, human blood cells, regardless of the multiplicity of the graft, retained their functional reactivity and were able to actively secrete the majority of the analyzed cytokines (8 of 10) in response to stimulation with concanavalin A. Diagnostically significant changes in the concentration of IFNγ, TNFα and IL-4 were detected for the characteristics of a specific antiplague response. For these marker cytokines, the greatest number of correlations have been revealed, both with each other and with changes in the level of other parameters: cytokines, immunoglobulins, T cells. The revealed multiple correlation links between the cytokine and immune status indices indicate the activation of both the cellular and humoral components of the antiplague immune response. The informative value of the complex analysis application of correlation interrelations between the humoral and cellular immunity parameters is shown to assess the level of immunological efficacy (actual vaccination) of vaccination in persons vaccinated against plague.

Objective - risk-oriented assessment of current epidemiological situation on Crimean hemorrhagic fever (CHF) in the Astrakhan Region. Materials and methods. Documents and reports of the Astrakhan Plague Control Station, Rospotrebnadzor Administration in the Astrakhan Region, and A.M. Nichogi Regional Infectious Clinical Hospital were utilized for the study. Key method of investigation was epidemiological analysis of morbidity rates among the population of the Astrakhan Region over the period of 2000-2016. The subject of the epidemiological analysis - 125 case histories. Results and conclusions. As a result of retrospective epidemiological analysis basic risk categories as regards Crimean hemorrhagic fever infection in the Astrakhan Region between 2000 and 2016 were identified and characterized. It was established that men of older ages are more prone to the disease (80 out of 125 cases - 64.0 %, 31-50 years old - 32 % and 51-70 years old - 14.4 %). Among the feminine population, CHF cases are also common within the same age range. High risk territories turned out to be 3 districts of the Region (Privolzhsky, Enotaevsky, Krasnoyarsky), medium risk - 3 districts, low risk - 4, and very low - 2. Risk group analysis revealed that during the last decade, CHF infection is more often registered in unemployed persons - 43.2 %, retired people - 17.6 %, and to a lesser degree - in salaried workers (10.4 %), agricultural laborers, and farm workers (8.8 %). In the majority of the cases (83-66.4 %) human infection with CHF occurred through the bite of a tick, or at the attempt to remove or crush it with unprotected hands. In 26 cases (20.8 %), risk factors were not identified. CHF in the Astrakhan Region has a pronounced spring - summer seasonality with the onset in the second half of April, peak values - in June (45 cases - 36 %) and a decline - in August. Among clinical forms of the diseases moderately severe was the prevalent one (83-66.4 %). Lethal cases were not registered.

The article covers the issues related to the scientific substantiation and methodological support of immunological monitoring of persons vaccinated against plague upon epidemic indications. The problematic issues of the methodology for the assessment of immunological efficiency (efficacy) of plague live vaccine (PLV) are noted. The current tasks and possible prospects for the introduction of immunological monitoring of persons vaccinated against plague upon epidemic indications have been defined. The algorithm of efficacy estimation of plague live vaccine in vaccinated (revaccinated) persons has been tested under real conditions. Analysis of the results of efficacy evaluation of plague live vaccine among vaccinated (revaccinated) people against plague living in the territories of natural foci of this infection has been performed. Demonstrated is the possibility of using immunological monitoring results in creating an objective basis for improving the strategy of specific plague prevention in natural foci of this infection. The priority areas for further optimization of the specific plague prevention in the territories of natural foci of the infection, including those related to the formation of individual regimen revaccination tactics, taking into account the possibilities of creating modern and effective vaccines, are outlined.

In 2014, in the central coastal part of the Pre-Caspian sandy natural plague focus, activation of epizootic process in the complex rodent settlements occurred. Objective of the study was to identify the factors that predetermined the development of intensive and extensive plague epizooties. Utilized were operational data from the Astrakhan, Elista, and Dagestan plague control stations, and personal investigation records gathered in the focus. Consequently to the high baseline numbers of rodents and fleas, mild winter weather in 2013-2014 population density of the vectors and carriers of the infection significantly exceeded long-term average annual indexes in the following spring. Total abundance rates reached up to 31.1 specimens per a hectare, being lowered up to 17.8 by the fall. Stock of the main vector of plague, N. laeviceps flea, amounted to 350 and to 120 per a hectare in the spring and autumn, respectively. All in all, in the course of the three rolling seasons isolated were 56 Y. pestis cultures: 17 strains - from the rodents, and 39 - from the fleas. The overall epizootic area totaled to 2300 km2. Plague epizooties were registered in the zone of sustained natural focality within the bonds of the Ilmen-Pridelta, Primorsky, and Chernozemelsky landscape-epizootic regions in the administrative territory of the Limansky District in the Astrakhan Region, Lagansky and Chernozemelsky Regions of the Republic of Kalmykia, and Tarumovsky Region of the Republic of Dagestan. Results of monitoring over the epizootic manifestations and plague carrier and vector abundance dynamics provided the basis for scheduling and performance of anti-epidemic activities, as well as for forecasting of the epidemic situation development in the focus.

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.