Objective of the review is to characterize the nature of epidemiological situation on HFRS around the world and to conduct a comparative analysis of intensity and dynamics of the epidemiological process in the Russian Federation by Federal Districts, as well as make forecast for 2020. The analysis of the epidemiological situation is based on the materials of the official websites of healthcare organizations in the USA and Europe, WHO, the data from operational monitoring carried out by the reference center for HFRS monitoring “Kazan Research Institute of Epidemiology and Microbiology”, materials provided by the Rospotrebnadzor Institutions in the constituent entities of the Russian Federation. The analysis included all administrative territories of the Russian Federation. Statistical processing was carried out by standard methods of variation statistics applying Excel software. The epidemiological situation on hemorrhagic fever with renal syndrome around the world and in Russia remains tense. In the Russian Federation, epidemically active foci are located in the European part of the country, in Western Siberia and in the Far East. Infections over the period of 2010–2019 were registered in 8 federal districts of the Russian Federation, in 58 constituent entities. However, the incidence distribution across the territory of the country was differential. In 97 % of the cases, the incidence was recorded in the European part of Russia. In the Volga Federal District, HFRS incidence amounted to 82.16 % of the total incidence recorded on the whole in Russia. High incidence rates are also recorded in the Central Federal District (CFD). Over the past 10 years (2010–2019), there has been an increase in the incidence of HFRS in the Central and North-West Federal Districts, and a decrease in the incidence in the Ural and Far Eastern Federal Districts. Varying degree of anthropogenic impact on the natural HFRS foci and climate change manifested in increased ambient air temperatures are of great importance for the spread of HFRS over the past decade. At the end of the review the forecast of the development of the epidemiological situation on HFRS in the Russian Federation for 2020 is presented.

The review used the data from operational monitoring carried out by the Reference Center for Monitoring over HFRS – “Kazan Research Institute of Epidemiology and Microbiology of the Rospotrebnadzor”, based on official data provided by the Rospotrebnadzor institutions in the constituent entities of the Russian Federation. Statistical processing was conducted using conventional methods of variation statistics applying the Excel program. Over the past decades, hantavirus diseases have become very relevant and spread throughout the world. In the territory of the Russian Federation, natural foci of HFRS are located in the European part of the country, Western Siberia and Far East. The most epidemically active foci are situated in the European part of Russia. Over the past decade, the intensive incidence rate of HFRS in the Russian Federation stayed within the range of 3.0–9.5 per 100 thousand of the population, the long-term average annual indicator – 5.2 per 100 thousand of the population. In 2020, 3845 cases of HFRS were registered (2.62 per 100,000 of the population). There was a decrease in the incidence of HFRS by 3.6 times, compared with the indicators of 2019. A factor that may have influenced the decrease in the incidence of HFRS was the depression of the epizootic process among small mammals, the main carriers of HFRS pathogens, due to natural and climatic factors. The nature of the distribution of HFRS incidence across the territory of the Russian Federation in 2020 was heterogeneous. Statistical processing of the data made it possible to identify 5 groups of territories that differ in the level of HFRS incidence. Almost all constituent entities of the Volga Federal District and the Kostroma Region belonging to the Central Federal District were classified as groups of territories with high and very high incidence rates. In 2021, the deterioration of the epidemiological situation is predicted in the summer-autumn period of the year in the Volga Federal District and four entities of the Central Federal District.

The paper presents analysis of epidemiological situation on hemorrhagic fever with renal syndrome around the world and in the Russian Federation over the period of 2009–2018. 5855 cases of hemorrhagic fever with renal syndrome were registered in Russia in 2018 (3.99 per one hundred thousand of the population). Downward trend is observed as compared to 2017 (by 29.6 %). Cases of cluster infection were not reported. It is established that the highest level of morbidity, exceeding the average level across Russia 3.9 times, was noted in the Volga Federal District, where 77.5% of the total cases occurred. The territory of the Russian Federation was differentiated by the HFRS incidence rates. The areas with high levels of morbidity included the entities of the Russian Federation with intensive index range between 9.08 and 41.39 per one hundred thousand of the population, among them Republics of Bashkortostan, Mari El, Tatarstan, and Mordovia, Udmurt and Chuvashi Republics, Kirov, Nizhny Novgorod, Penza, Samara, Ulyanovsk, Kostroma, Yaroslavl, and Jewish Autonomous Regions. The forecast for preservation of tense epidemiological situation on HFRS incidence in the territory of the Volga Federal District was substantiated.

A «green» method of obtaining gas separation composite membranes from cellulose solutions and its mixtures with chitosan in orthophosphoric acid is proposed for industrial use, and differs from the viscose method of producing cellophane and other known methods for producing cellulose gas separation membranes without gaseous emissions and wastewater. It is shown that new composite cellulose membranes on a viscose fabric substrate are characterized by high productivity and selectivity for O2/ N2 pairs, comparable to the values obtained for known membranes made of synthetic polymers, as well as increased mechanical strength. The developed composite membranes demonstrate an inverse selectivity for the CH4/CO2 pair, which is not typical for gas separation membranes described in the literature with cellulose-based selective layers.

The study presents a characteristic of the current epidemiological situation on leptospirosis in the Republic of Tatarstan, investigation of the circulation of leptospirosis agents among the population of small mammals, and the species composition of Leptospira that caused diseases in humans.Materials and methods. The paper contains the data on the incidence of leptospirosis among the population in the Russian Federation (RF) for the period between 2000 and 2018, in the Republic of Tatarstan – since 1998, submitted by the Rospotrebnadzor Administrations in the constituent entities of the Russian Federation, materials of the Center for Hygiene and Epidemiology in the Republic of Tatarstan and the Main Veterinary Administration of the Republic of Tatarstan.Results and discussion. We have carried out the analysis of the epidemiological situation in the Republic of Tatarstan for the period of 1998–2018, by the administrative territories of the republic. The incidence of human leptospirosis caused by various leptospira serogroups has been assessed. In total, 112 people got infected with leptospirosis during the analyzed period. Also the data of epizootiological survey of small mammals inhabiting the natural foci of leptospirosis in the republic are presented. Laboratory tests of 1565 samples from mouse-like rodents for the presence of leptospirosis pathogens have been performed. 1.9 % of the tests gave a positive result. Dominant in the Republic of Tatarstan are the serogroups of Leptospira – Leptospira grippotyphosa and L. hebdomadis. The results of laboratory studies on the carriage of leptospira among small mammals and contamination of environmental objects indicate the circulation of pathogens of leptospirosis in the population of small mammals, habitant in forest shrub, near-water and meadow field stations of the republic. The red vole prevails in this community, the average index of its dominance is 66.7 %. Epizootiological monitoring point to a latent epizootic process in the community of mouse-like rodents.