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Rationale. An important task is to monitor the incidence of tularemia among the population of Kazakhstan. Natural foci of this infection occupy large areas. In some regions with large numbers of rodents and ectoparasites and low vaccination coverage, human cases of tularemia have been reported.The aim of the study. To carry out retrospective analysis and to study modern spatiotemporal characteristics of tularemia in the West Kazakhstan and North Kazakhstan regions in order to improve the effectiveness of preventive measures.Materials and methods. In our work, we used public records, the results of an epizootological survey of tularemia natural foci and the official data from the Departments of Sanitary and Epidemiological Control of two regions on the human cases of tularemia in 2000–2021. We used descriptive statistics methods, relative and absolute indicators of the tularemia incidence in the population for the analysis. The phenotypic and genetic properties of the strains isolated in 2000–2021 were studied according to the guidelines.Results. A retrospective analysis of the tularemia incidence among the population of the North Kazakhstan and West Kazakhstan regions showed an improvement in the epidemic situation. Over the past 20 years, 4 human cases of tularemia have been registered in the West Kazakhstan region, while the epizootic potential was quite high; more than 300 strains of the tularemia microbe were isolated during the studied period. In the North Kazakhstan region from 2000 to 2021, 11 human cases of tularemia were registered; when studying rodents, mammals and environmental objects, single positive samples for specific tularemia antibodies and antigens were detected; no strains of tularemia microbe were isolated.Conclusion. An analysis of long-term data on the epizootic and epidemic activity of tularemia natural foci, processed using descriptive statistics and GIS technology, made it possible to identify places of long-term persistence of the tularemia agent in the natural focus of the North Kazakhstan and West Kazakhstan regions and to create an electronic map of the territories endemic for tularemia to determine the scope of preventive measures.

The study of freshly isolated cultures is necessary to form an objective idea of the properties of plague microbe natural populations. The analysis of the levels of investigating the properties of strains has been carried out and the characteristics of Yersinia pestis in Kazakhstan are presented. The results of studying the phenotypic and genetic properties of plague microbe natural strains are provided. Following the epizootiological survey of natural plague foci, the museums of live cultures at plague control stations annually receive strains of plague pathogen, which are transferred to the National Collection of Microorganisms of the National Scientific Center of Particularly Dangerous Infections (NSCPDI). One of the main points of Y. pestis strains analysis is the determination of their typicality/atypicality. The study of strains begins at the moment of their isolation by anti-epidemic units. The primary identification of strains is carried out in laboratories of anti-epidemic units by morphology, sensitivity to plague and pseudotuberculosis bacteriophages, fermentation of glycerol, rhamnose and sucrose. In the laboratories of plague control stations and departments, fermentation of maltose and arabinose, denitrification, amino acid requirements, virulence, sensitivity to antibiotics are additionally investigated. Analysis of strains virulence includes determination of calcium dependence, the presence and amount of F1, pesticinogenicity and sensitivity to pesticin 1 and virulence for white mice. The assessment and preservation of the collected gene pool in the NSCPDI National Collection includes various activities, one of the main ones is an in-depth study of all features using standard microbiological methods, molecular methods for complete identification and creation of a data bank containing information about the genome of strains at different intensity of the epizootic process. The NSCPDI has a digital database on the registration and movement of strains, equipment for molecular research. The collection evaluates properties, systematizes information, and ensures the viability of plague pathogen strains for longterm storage.

Background. Epidemiological and epizootological monitoring of natural plague foci requires an integrated approach to solving problems, taking into account the phenotypic and genetic variability of Y. pestis and zoning of natural plague foci. The introduction of a new molecular genetic methodology aimed at studying the genomic polymorphism of the plague pathogen provides reliable results for the differentiation of not only groups, but also individual strains.The aim. To determine the genotypes of the plague microbe from different autonomous foci of the Republic of Kazakhstan.Materials and methods. 105 strains of Y. pestis isolated from various natural plague foci of Kazakhstan in 1951–2015 were studied. The phenotypic properties of the strains were studied using standard microbiological methods. A polymerase chain reaction (PCR) was used to detect fragments of the cafl, pst and YPO2088 genes. Multilocus variable number tandem repeat (VNTR) analysis (MLVA) was performed for 25 VNTR loci.Results. The phenotypic properties of the strains were preliminarily studied and the strains of the plague microbe were tested for specificity using the Pest-Quest test system (Kazakhstan). The PCR study confirmed the species-specific affiliation of Y. pestis strains. A variety of strains with typical phenotypic characteristics was revealed. MLVA for 25 key loci (MLVA25) revealed that the studied strains of the plague microbe are phylogenetically closest to the Mediaevalis biovar representatives. A phylogenetic tree of the studied strains has been obtained. It was found that 9 genotypes circulate on the territory of Kazakhstan, and their distribution in certain natural plague foci was determined.Conclusions. The resulting clustering indicates the relationship between the strain groups obtained on the dendrogram by the MLVA25 method and the territories of certain natural plague foci.

Almost every year in Kazakhstan, cases of diseases of animals and people with anthrax are recorded. The incidence rate of people with anthrax in the period from 2000 to 2018 ranged from 0.01 to 0.24 per 100 thousand people. In the territory of the East Kazakhstan region, the incidence rate is higher than in the republic.Objective: a retrospective analysis of anthrax outbreaks in the East Kazakhstan region from 2000 to 2018.Methods: a retrospective analysis using statistical, cadastral data, archival funds, the results of participation in the investigation of outbreaks of infection.Results. Since 1938, cases of animal and human disease of anthrax have been recorded in East Kazakhstan. Infection of humans occurs during the slaughter of animals. In Zharma, Urjar, and Ayagozskiy areas most of all are anthrax foci of soil. In 67 % of cases, outbreaks of anthrax were recorded in these areas.Conclusion. The relative incidence rate of anthrax in people in East Kazakhstan is from 0.07 to 0.27, since 2001 it is higher than the republican indicator.In the East Kazakhstan region from 1997 to 2018, 37 people fell ill with anthrax. The form of the disease is skin, in 8.1 % secondary sepsis. In the remaining patients, the diseases were mild (70.3 %), ended in recovery. The source of human infection is mainly cattle. The isolated strains of B. anthracis have typical properties, they are included in cluster A1a, A3b (MLVA-8). The strains isolated in 2016 are similar to the strains isolated in the Almaty region (MLVA-25). Grouped with a number of European, Asian and African strains from France, Germany, Italy, Tajikistan, Pakistan, Korea and Namibia. The presence of a significant number of soil foci of anthrax in the territory of the East Kazakhstan region, not fully the implementation of veterinary and sanitary preventive measures leads to an exacerbation of the situation for anthrax.

Today, anthrax is recorded in many countries around the world, in Kazakhstan – in the form of sporadic cases or small outbreaks. Despite the endemicity of anthrax in Kazakhstan, the genetic diversity strains is not well described. At the moment, MLVA-25, which is sufficient for molecular and epidemiological monitoring, is recognized as one of the most discriminatory methods of genotyping.Objective: to determine the cultural and morphological properties, the genomic characteristics of the strains of the anthrax pathogen, their geographical distribution in the territory of Kazakhstan during the outbreaks in 2016, a comparative analysis with collection strains isolated since 1962.Methods: microbiological, genetic research methods were used in the work.Results. We investigated 11 strains of B. anthracis, which were isolated in 2016 in Kazakhstan. For comparison of genotypes, 26 strains were used from the collection of pathogenic microorganisms of the A.M. Aykimbaev’s Kazakh Scientific Center for Quarantine and Zoonotic Diseases. Phylogenetic analysis clustered 37 strains of B. anthracis into three clusters and 23 genotypes.The results of studying the phenotypic properties of anthrax strains by the main identification tests showed that all the strains studied in the experiment and isolated from 1961 to 2016 had biological properties characteristic of typical of B. anthracis strains.The anthrax strains isolated in 2016 are characterized as significant variability, as well as the circulation of the same genotypes and clusters in different areas of Kazakhstan. MLVA-profiles of analyzed Kazakhstan strains are unique and do not fully coincide with any studied strain from MLVAbank. On the MST-tree, Kazakhstan’s strains are located in three clusters, as on the phylogenetic tree.Conclusion: Molecular genetic analysis of B. anthracis strains enhances the ability of epidemiologists to track the sources and pathways of infection.It is necessary to improve the tracking system for strains of especially dangerous infections in Kazakhstan using modern molecular genetic methods.

In 2017, from October 15 to November 21, 5 cholera cases imported from India – 3 patients and 2 carriers of V. cholerae – were recorded in Almaty. The patients recovered from the disease. Objective of the study was to characterize the imported cases of cholera and investigate the properties of cholera vibrio strains isolated from patients and carriers of V. cholerae. Materials and methods. Revised were the medical records; blood sera, feces from patients and contact persons were assayed. Studied were sensitivity spectrum to antibacterial preparations of isolated V. cholerae strains according to the “Methodological guidelines on laboratory diagnosis of cholera”, dated September 27, 2010; No 252. Epidemiological, microbiological, immunological and molecular-genetic methods were applied for investigation. Results and conclusions. Consequently to molecular genetic studies, genes of specificity, wbeN and toxicity (epidemic significance), ctxA, tcpA were detected in samples from 3 patients and 2 contact persons. The isolated strains were identified as Vibrio cholerae O1 Eltor Inaba in two cases, and in one case – as Vibrio cholerae O1 Eltor Hykoshima, Heiberg group I, toxigenic, hemolysis negative in Greig test, virulent, highly sensitive to ciprofloxacin, doxycilin, erythromycin, tetracycline and moderately sensitive to levomycetin. It was established that the country of export in all the cases was India. Relevant anti-epidemic and preventive measures were undertaken to localize and eradicate the foci in order to prevent possible threat of epidemic spread of infections among the population.