Russian Scientific Research Institute Microbe

Modern automatic steam sterilizers make it possible to implement «short» sterilization modes. The use of such modes is effective for products of simple geometric shape with a smooth surface without internal channels. In the manufacture of medicines and medical products, the Russian Anti-Plague Institute Microb of Rospotrebnadzor uses reusable glass bottles, which are sealed with cotton-gauze stoppers and sterilized at a temperature of 132 ° C for 20 minutes. The purpose of the work was to select a material for replacing cotton-gauze plugs and to confirm the possibility of using a «short» sterilization mode. Packaging material for sterilization of medical devices has been selected for the manufacture of paper caps on the neck of bottles. Experimentally, physical, chemical and biological methods have confirmed the necessary temperature values and sterility inside the bottle container during sterilization at a temperature of 134 ° C for 7 minutes. The advantage of this mode is the reduction of the sterilization cycle time compared to the previously used one and the absence of the need to use cotton-gauze plugs. The results of the experimental work will serve as the basis for the validation of the selected sterilization regime and its introduction into production practice. Given the identity of the composition and characteristics of packaging materials for sterilization from different manufacturers, their use is also possible for bottle capping. Keywords: steam sterilization, «short» sterilization modes, sterilization of medical products, packaging paper for sterilization.

Introduction. The COVID-19 pandemic has revealed a whole complex of problems related to mathematical modeling of the epidemic process and assessing the effect of preventive and anti-epidemic measures in modern complex societies. Along with this, the accumulation of significant factual data has spurred the active development of agent-based models, in which each agent (a hypothetical person) has a unique set of characteristics and interaction methods determined based on real sociological and demographic data. Aim and objectives. Development and demonstration of the capabilities of the epidemiological agent-based model POEM platform (POpulation Epidemiological Model). Materials and methods. The POEM platform is developed based on the source code of one of the most widely used agent-based models worldwide, Covasim, taking into account the demographic and organizational-administrative conditions specific to the Russian Federation. Results. Computational experiments have shown that due to individual variability in the dynamics of infection development and the specifics of disease registration, even mass events, while leading to an actual increase in the number of infected individuals, do not have a significant impact on the shape of the curve of registered disease incidence. It has been shown that intercity traffic flows at a level of 0.1% of the population per day have a minimal effect on the dynamics of the epidemic's development, while the effect of a 1% population outflow per day sharply reduces the effect of strict anti-epidemic measures implemented in only one particular city. Using the example of the Voronezh region, the transition from the Delta variant to Omicron in early 2022 was modeled, and a high degree of correlation was shown between the model dynamics and the actual ratio of virus variants observed. Conclusion. The model is fully implemented within the Russian system on the server of the Research Institute for System Biology and Medicine of Rospotrebnadzor and can be used to conduct digital epidemiological experiments to predict the effectiveness of proposed anti-epidemic measures.

Multilocus variable number tandem repeat analysis (MLVA) is one of the highest-resolution methods for subtyping genetically monomorphic pathogens of especially dangerous infections. The MLVA25 method of subtyping based on 25 VNTR loci, which is widely used in molecular epidemiological studies, has shown high efficiency in the analysis of Yersinia pestis strains. However, the question of the efficiency of individual VNTR loci in MLVA25 of Y. pestis strains of medieval biovar of main subspecies prevalent in most natural plague foci of Eastern Europe and Central Asia remains open. The aim of the present work was to evaluate the efficiency of different VNTR loci and to optimize the MLVA25 method for differentiation of Y. pestis strains of medieval biovar from the plague foci of Russia and other CIS countries located in Eastern Europe and Central Asia. Whole genome sequences of 220 strains of Y. pestis of medieval biovar of main subspecies and 31 strain of Y. pestis belonging to other phylogenetic lineages were analyzed. The sequences of VNTR loci identified in these strains were entered into the Bionumerics 7.6.3 software for subsequent phylogenetic analysis by UPGMA. MLVA25 genotypes of 251 Y. pestis strains used in this work were identified. According to the results of the statistical analysis of these loci, 126 individual genotypes were detected in the strains of medieval biovar, which corresponds well with the discrimination ability of the subtyping system (DP = 0.98). Efficient loci with high discrimination power were identified, which have the greatest impact on the differentiation of the strains of medieval biovar by genotype. An MLVA subtyping system for Y. pestis strains of medieval biovar has been optimized, into which 12 VNTR loci were included.

Introduction. The expression of the ctxAB and tcpA-F genes encoding the main pathogenicity factors of the Vibrio cholerae is controlled by regulatory genes. The structure of these genes has not been fully studied in the pathogen strains isolated during different periods of the current pandemic. The aim of the study was a comparative analysis of the structure of regulatory genes of V. cholerae O1 biovar El Tor strains isolated on the territory of the Russian Federation and neighboring countries during the seventh cholera pandemic. Materials and methods. The nucleotide sequences of the complete genomes of 29 toxigenic strains isolated from 1970 to 2023 were analyzed. The analysis was carried out using BioEdit v7.2.6.1 software and Blast tool. Results. The analysis of ten regulatory genes (toxT, aphA, aphB, hns, hapR, vieA, luxO, luxT, carS, carR) was carried out. Almost all strains were found to have a thymine insertion in the hapR gene at position 219. The exception was V. cholerae strain M3208 (Tambov, 2023), which had an insertion of five nucleotides in this gene. Mutations of the luxO gene with an unknown effect were detected in 44.8% of the studied strains. In 46.7% and 33.3% of the studied genetic variants carrying the ctxB1 allele, non-synonymous substitutions were detected in the hns (G319A) and vieA (C235T) genes, respectively. All genetic variants with the ctxB7 allele have mutations in both the hns and vieA genes. Three genetic variants with the ctxB7 allele, imported to the Russian Federation in recent years, contain an altered structure of the carR gene (G265A). Conclusion. The structure of genes (toxT, aphA, aphB, carS, luxT, hapR) of V. cholerae O1 El Tor strains remains unchanged for the majority of the studied isolates. At the same time, variability in the hns (G319A), vieA (C235T) and carR (G256A) genes was detected. Mutations in these genes can be used as genetic markers of modern V. cholerae O1 El Tor genetic variants.

The paper considers the key areas of international activities of the Federal Service for Surveillance on Consumers’ Rights Protection and Human Well-being in strengthening cooperation with specialized agencies of foreign countries in the global provision of sanitary-epidemiological welfare of the population at the current stage. Consistent work to strengthen the international network to counter emergency situations of a sanitary and epidemiological nature through effective interaction in the field of rapid response with partner countries in the near and far abroad, including through the organization of joint scientific and practical centers for the study and prevention of infectious diseases is presented. It is shown that the programs being implemented are aimed at strengthening the national healthcare structures of partner countries to achieve independence in the implementation of monitoring and anti-epidemic measures and building a single epidemiological space, independent of the influence of global and regional geopolitical fluctuations. The relevance of increasing interstate cooperation in the field of analysis and control of biological threats, primarily infectious diseases with the potential for emergencies of a sanitary and epidemiological nature of international concern, in the South American region is considered. The currently expanding strategic biosecurity collaboration with the Bolivarian Republic of Venezuela through the establishment of the first joint research center in the South American region is described. The first results of the joint work of Russian and Venezuelan specialists are presented, confirming the successful integration of Russian experience in monitoring and preventing biological threats into the system of ensuring the sanitary and epidemiological well-being of the Venezuelan population. Promising areas for further joint research are discussed.

Introduction. Immunomodulatory drugs (IMD) have great potential to increase the nonspecific reactivity of the organism in a set of measures for emergency prevention of plague. The purpose of the work is to evaluate the protective effectiveness of the use of IMD of different groups in experiments on modeling infection with a highly virulent strain of the plague microbe. Materials and methods. IMD (rIFN-γ — recombinant interferon-gamma, PO — azoximer bromide, synthetic immunomodulatory oligopeptides O1, O2, O3) was administered to white mice and guinea pigs subcutaneously thrice by the schedule 3 days, 1 day, and 1 hour prior the infection with a virulent test strain of plague Yersinia pestis 231 (708) at dose from 1 to 625 CFU. In addition, the effect of IMD on the production of IFN-γ and interleukin-10 was investigated in white mice before infection. Results. The study of the effect of IMD on the survival of unvaccinated biomodels made it possible to establish that only rIFN-γ and PO increase the survival of two types of laboratory animals by 20–50% and significantly increase the LD50. All tested IMD contribute to an increase in the average life expectancy of biomodels by at least one day. An increase in spontaneous and mitogen-induced cytokine production was found only in white mice receiving rIFN-γ and PO, which correlates with animal survival rates. Conclusion. The obtained data indicate the effectiveness of the use of IMD, especially rIFN-γ and PO in protecting the macroorganisms from infection with Y. pestis, which determines the prospects for research on the further improvement of emergency prevention of plague.

This paper provides an analysis of the results of joint work of Russian and Congolese infectious disease specialists and epidemiologists to decipher the etiology and causes of the outbreak of intestinal infections in Dolisie (Republic of the Congo) in the summer of 2023. It has been found that the increase in the incidence of intestinal infections was caused mainly by the agents of typhoid fever and dysentery; tropical malaria was a combined pathology. No cases of cholera patient detection were registered. Failure of water supply system, domestic disrepair, and low public awareness about prevention of intestinal infections contributed to the active transmission of pathogens. The combination of epidemic process manifestations testified to the aquatic nature of the outbreak. Also, cases of pathogen transmission through contact household route were recorded, food transmission was not excluded. Patients with severe and complicated forms of typhoid fever and shigellosis accounted for 50 % of those hospitalized. There was delay in seeking medical care. The available regimens of antibacterial therapy were ineffective, since there was no possibility of laboratory confirmation of the diagnosis with determination of sensitivity to drugs. Uncontrolled treatment facilitated the emergence of antibiotic resistance in pathogens, prolonged bacterial release and subsequent spread of infection. Infectious disease specialists and epidemiologists of the Rospotrebnadzor provided consulting and practical assistance to Congolese colleagues, developed and presented recommendations for optimizing anti-epidemic and therapeutic measures, taking into account the results of assessment of the causes for onset and development of the outbreak.