Introduction: Conventional approaches to assessing the sanitary and epidemiological status based on discrete analysis of heterogeneous environmental factors fail to fully consider a complex nature of their impact given uncertainty of available data, variability, and combined exposures. This logically creates a systemic limitation that reduces the accuracy of predicting human health risks as well as effectiveness and efficiency of preventive measures. The relevance of the study is attributed to the necessity of improving instruments for assessing sanitary and epidemiological well-being under dynamic changes in economic and sociodemographic factors.

Objective: To develop a methodology for a comprehensive assessment of potential human health risks based on integrated heterogeneous environmental health data using the apparatus of fuzzy set theory.

Materials and Methods: Within this study, we performed systemic and hygienic analyses, employed mathematical modeling (the fuzzy set theory) and health risk assessment. We conducted a retrospective study of data retrieved from Rospotrebnadzor’s official reports covering 65 benchmark indicators describing quality and safety of environmental media (ambient air, drinking water, and soils), occupational conditions, etc., for 2014–2023.

Results: We developed methodical approaches to calculating a comprehensive metric of total potential health risk (R) from violations of sanitary and epidemiological well-being, which allow grouping of areas by five risk categories, from negligible to very high. Application of the fuzzy set theory made it possible to formalize and consider data uncertainty and variability of factors and ensured reliable and representative assessment. Methodology testing in three Russian regions (Tambov Region (R = 0.34), Krasnoyarsk Krai (R = 0.57), and Perm Krai (R = 0.43)) proved the consistency of estimates with observed levels of environmental pollution, thus confirming its validity.

Conclusions: The developed methodology is a new stage in updating the conventional hygienic monitoring ensuring its transformation into a prognostic system able to adapt to dynamic changes in environmental factors and preventive risk management.

Introduction: Insulin resistance (IR), a major precursor of type 2 diabetes affecting 44.2 % of Indonesians, was assessed using the triglyceride–glucose (TyG) index, a more practical and economical measure. Comprehensive investigations linking IR with metabolic, dietary, and lifestyle factors remain scarce in Indonesia.

Objective: To assess the metabolic, dietary, and lifestyle factors associated with insulin resistance among non-diabetic adults in Indonesia.

Materials and Methods: This cross-sectional study used baseline data from the Non-Communicable Disease Risk Factor Cohort Study in Bogor, Indonesia. From 5,329 respondents, 251 with fasting glucose ≥126 mg/dL and 463 with incomplete data were excluded, yielding 4,615 participants. Insulin resistance was defined by a TyG index ≥8.5. Variables with p < 0.25 in chi-square tests were entered into multivariable logistic regression to identify independent predictors. Odds ratios (ORs) and 95 % confidence intervals (CIs) were reported.

Results: Multivariable analysis revealed several strong predictors of the TyG index among non-diabetic adults. Male sex (OR = 3.90, 95 % CI: 3.15–4.82), high total cholesterol (OR = 4.36, 95 % CI: 3.72–5.11), and low HDL cholesterol (OR = 4.24, 95 % CI: 3.62–4.97) demonstrated the highest associations. Frequent consumption of packaged beverages (>3 packs/day) showed the greatest dietary effect (OR = 5.10, 95 % CI: 1.38–18.82). Central obesity (OR = 2.39, 95 % CI: 2.01–2.84) and age ≥ 40 years (OR = 1.67, 95 % CI: 1.41–1.98) were also significant predictors.

Conclusion: Insulin resistance (TyG index ≥ 8.5) is strongly linked to metabolic, dietary, and modifiable lifestyle factors and may serve as a practical screening tool in urban populations.

Introduction: A close relationship between the chemical composition of consumed water and the elemental structure of the human body has been proven.

Objective: A comparative physiological and hygienic assessment of the chemical composition of drinking water in the cities of Tyumen, Khanty-Mansiysk, and Salekhard.

Materials and Methods: From June to September 2024, 60 samples of tap water taken from three cities of the Tyumen Region were tested using atomic absorption spectrometry and capillary electrophoresis to determine Ca, Mg, Cu, Zn, Se, and Fe levels. The results were then compared with the maximum allowable concentrations of the chemicals and WHO drinking water health-based values.

Results: Calcium concentrations in all water samples were 2.4–7.3 times lower than the recommended range, with the lowest levels found in Salekhard and the highest in Tyumen (p < 0.001). Magnesium concentrations were also 4.6 to 5.5 times below the health-based value in all samples. Copper, zinc, and selenium levels were many times lower than the recommended ranges, with a significant excess of those for Zn and Se in Tyumen over those in Khanty-Mansiysk (p = 0.020 and p < 0.001) and Salekhard (p = 0.005 and p < 0.001), respectively. Iron concentrations in drinking water in Tyumen were 4 times lower than the maximum allowable level, in Khanty-Mansiysk they were at the upper limit, and in Salekhard they exceeded it.

Conclusions: Ca, Mg, Cu, Zn, and Se concentrations in the water samples from the cities of Tyumen, Khanty-Mansiysk, and Salekhard do not exceed permissible values but they fail to comply with the recommended levels. IIn Salekhard, iron concentrations in tap water exceeded both the permissible and recommended levels.

Introduction: Issues of teaching children with special educational needs in classes attended by students with similar or different disabilities, as well as the search for optimal conditions for developing their learning activities, remain poorly understood.

Objective: To establish intensity and efficiency of involvement of students with disabilities in the learning process.

Materials and Methods: The study was conducted in February to May 2022 in Moscow and the Moscow Region involving 65 elementary school students with intellectual disabilities, mental retardation, musculoskeletal disorders, hearing and speech disorders, autism spectrum disorder, and severe multiple developmental disorders. The sample consisted of four classes of children with different health conditions (n = 31) and four classes of those with the same condition (n = 34). Timing was the primary method. Special protocols were developed for this study to record the duration and sequence of learning activity elements during the lesson. Input data included the grade, day of the week, subject, and its content.

Results: Children grouped by disability demonstrated longer concentration on tasks, were less easily distracted, and required rarer activity changes (Mann–Whitney U test: U = 312.5, p = 0.002; U = 270.0, p = 0.001; and U = 362, p = 0.004, respectively). They were more active during the lessons (activity variation ranged from 83 to 100 %) than children in mixed classes (23 to 75 %) (p < 0.05).

Conclusion: The results show that students with similar health conditions attending the same class of a special needs school demonstrate higher academic performance compared to their peers in mixed classes.

Introduction: According to recent statistics, more than 80 % of medical doctors are currently subject to occupational burnout.

Objective: To study the features of job burnout among physicians and surgeons in a specialized hospital.

Materials and Methods: The study population comprised seven groups consisting of 52 gastroenterologists, 58 cardiologists, 48 medical oncologists, 71 general surgeons, 30 cardiac surgeons, 65 surgical oncologists, and 75 controls of engineering, technical and economic specialties. The level of occupational burnout among medical workers was assessed using the Boyko method. The statistical analysis was carried out using the programming language and environment R v.4.4.1, RStudio 2024.09.1+394. The chi-square test was used to compare the percentages.

Results: Surgeons were noted for a more rapid formation of job burnout phases. Surgical oncologists were at the highest risk of rapid formation of phases leading to exhaustion. When assessing tension, resistance and exhaustion phases in cardiac surgeons based on the Boyko test, we established that the stress phase was forming in 70.0 % and had formed in 13.3 %, the resistance phase was forming in 40.0 % and had formed in 43.33 %, while the exhaustion phase was forming in 96.67 % of the respondents; no surgeons with an already developed exhaustion phase were identified in this group.

Conclusion: Knowledge of the differences in the severity of occupational burnout for different groups of physicians and surgeons of various specialties can be used in developing burnout prevention programs for health professionals.

Introduction: National food composition databases are becoming increasingly important. They play a key role in nutritional epidemiology research and enable consumers to make informed food and dish choices by providing sciencebased information about their energy and nutritional value.

Objectives: To analyze national databases of the chemical composition of foods and dishes, to assess the completeness of information on the contents of macroand micronutrients, vitamins, minerals, and biologically active substances, to establish availability of various built-in analysis tools and the convenience of their use.

Materials and Methods: We have reviewed seven large national food composition databases for the United States, Australia, Switzerland, France, Portugal, Denmark, and the United Kingdom as of September 2025 using open sources of official information for the analysis. Database inclusion criteria were government ownership, web interface availability, and application in dietary analysis. Evaluation criteria included the number of foods and dishes, the range and completeness of the list of nutrients, the ability to download, and availability of various additional tools.

Results: We established that the most critical limitation for the majority of databases is the incomplete nutrient composition for all declared foods and dishes, which prevents an objective assessment of the dietary intake of a nutrient for which data is missing.

Conclusion: A set of criteria selected for the architecture, contents, and tools of the developed software with a user interface for processing, storing, analyzing, and verifying data on the chemical composition of food products, intended for the creation and maintenance of the Russian national food composition database, is substantiated.

Introduction: Seasonal influenza circulates in an epidemic pattern, with periodic shifts in the dominant subtype driven by antigenic drift and population immunity. Mutations in surface proteins – particularly within the hemagglutinin receptor-binding site (RBS) – enable the virus to evade host immune responses. Among these, the D222G/N substitution has been associated with increased virulence of A(H1N1)pdm09 viruses.

Objective: Genetic characterization of viruses detected in influenza cases in the Russian Federation in the 2024–2025 epidemic season.

Materials and methods: From September 10, 2024, to June 19, 2025, 1,931 specimens from patients with influenza, including 240 autopsy samples, were tested by RT-PCR. For 420 samples with sufficient genetic material, influenza virus genome sequences were obtained using NGS.

Results: During the 2024–2025 flu season, A(H1N1)pdm09 viruses predominated in the Russian Federation. Influenza B/Victoria lineage viruses were less frequent while influenza A (H3N2) cases were sporadic. Most fatal cases occurred in individuals belonging to risk groups, with a notably low vaccination coverage among them. Among fatal A(H1N1)pdm09 cases, the HA-D222N mutation – a marker of enhanced virulence – was detected in the major viral variant in 19.0 % of sequenced samples. Additionally, D222G/N mutations were identified in minor variants in 10.1 % of fatal cases. Notably, the D222N mutation in the major variant was also found in one recovered A(H1N1)pdm09 case (0.5 %). Resistance markers to antiviral drugs – oseltamivir (1.9 %) and baloxavir marboxil (0.4 %) were detected in 6 of all sequenced A(H1N1)pdm09 viruses (2.3 %).

Conclusion: The detection of HA-D222G/N mutations associated with increased virulence and fatality from A(H1N1)pdm09 viruses underscores the importance of vaccination as a key preventive measure, particularly for population groups at risk, and timely treatment for influenza.

Introduction: Nontuberculous mycobacteria are widespread in the environment and their pathogenic species can cause mycobacteriosis, especially of the respiratory system.

Objective: To study of the species diversity of nontuberculous mycobacteria and to give an epidemiological description of cases of isolation of nontuberculous mycobacteria in the Republic of Mari El in 2015–2024.

Materials and Methods: The conducted retrospective epidemiological study was descriptive and evaluative. We analyzed anonymized records of 30,617 patients seeking care at tuberculosis and general health facilities of the Republic of Mari El in the years 2015 to 2024. The statistical analysis was performed using StatTech v. 4.8.2 by StatTech LLC, Russia.

Results: We identified 544 people with nontuberculous mycobacteria (mean age = 60 years), most of whom were men (284; 52.2 %). We established that 338 (62.1 %) patients were urban residents and 206 (37.9 %) lived in the countryside. Nontuberculous mycobacteria were repeatedly isolated from 156 (28.7 %) and only once – from 388 (71.3 %) cases. The most common species included M. gordonae (n = 168; 29.5 %), M. intracellulare (n = 122; 21.4 %), and M. avium (n = 81; 14.4 %). At this, 104 patients (19.1 %) were diagnosed with mycobacteriosis, of which 63 (60.6 %) were women. In most cases, mycobacteriosis was induced by slow-growing M. intracellulare, M. avium, and M. gordonae. The analysis of the number of patients showed a 4.9-fold increase. Most cases with isolated nontuberculous mycobacteria lived in the city of Yoshkar-Ola (n = 295, 54.2 %), Medvedevsky (n = 61, 11.2 %) and Zvenigovsky (n = 33, 6.1 %) districts, the town of Volzhsk (n = 30, 5.5 %), Sovetsky (n = 19, 3.5 %) and Volzhsky (n = 17, 3.1 %) districts.

Conclusions: Our study allowed us to determine regional characteristics of nontuberculous mycobacteria isolated from human specimens and establish the prevalence of slow-growing species in the Republic of Mari El.

Introduction: HIV infection remains one of the major public health problems worldwide. Since the high genetic diversity of HIV and the formation of resistance to antiretroviral drugs have a negative impact on achieving the goal of eradicating the infection, it is important to monitor circulating HIV-1 variants on different territories on a regular basis.

Objective: To conduct an epidemiological and molecular genetics analysis of HIV-1 variants circulating in the Magadan Region, including the analysis of drug resistance mutations.

Materials and methods: HIV infection rates were analyzed based on data provided by the Center for AIDS Control and Prevention in the Magadan Region and information from the Federal State Statistics Service for 2019–2024. Molecular genetics testing was performed for 39 blood plasma samples using Sanger sequencing of fragments of the pol gene encoding the protease and part of the HIV-1 reverse transcriptase.

Results: HIV-1 sub-subtype A6 prevailed in the examined group (87.2 %). We detected two imported cases of subtype B infection (5.1 %) and the recombinant of CRF63_02A6 in three cases (7.7 %). Mutations associated with the development of antiretroviral drug resistance were found in 1 of 14 untreated patients (7.1 %) and in 8 of 25 patients (32.0 %) undergoing therapy.

Conclusion: The results highlight the importance of widespread introduction of modern molecular genetics methods (sequencing, phylogenetic analysis, and bioinformatic techniques) into the HIV surveillance system in certain territories of the Russian Federation.

Introduction: The experience of individual countries in developing quality management systems provides a valuable resource for borrowing the most successful projects and understanding the resulting effects.

Objective: To present methodological approaches to developing a law enforcement framework for the scope of accreditation of a parasitology laboratory given the resource availability.

Materials and Methods: We conducted a comparative legal analysis of enforcement of the approved Rosaccreditation guidelines for elaborating the parasitology section of the scope of accreditation based on 21 regulations, seven instructions and guidelines. A methodological approach was used to create the key elements of the scope of accreditation for parasitology laboratories, taking into account regulation of its facilities by two or more different-level documents with explanations.

Results: The article describes the approaches to documenting the scope of accreditation under different levels of current regulations. When documenting the scope for parasitology laboratories, the facilities of which are regulated by two or more legal documents, the following recommendations must be implemented:

1)       The scope of accreditation should include all documents based on a practical approach to the readiness of the testing laboratory to perform various target tasks; and

2)       Methodological support for testing should meet all resource availability parameters for assessing the quality of procedural, organizational, and managerial solutions during testing.

The article also describes the main principles of enforcement of the guidelines issued by the Russian Federal Accreditation Service in 2019 for describing the scope of accreditation of parasitology laboratories, the conformity assessment of which is regulated by two or more legal acts simultaneously, e.g. Technical Regulations of the Customs Union, state standards and/or sanitary rules, and can be chosen by the testing laboratory depending on the resources.

Conclusion: The proposed approach to creating structural elements of the scope of accreditation and explanations to it may contribute to improving training of specialists for accreditation tasks.