The mucosal membranes of the human body play a crucial role in the development, maintenance, and regulation of barrier functions and immune homeostasis, representing an integral component of the overall immune system. Mucosal vaccines elicit immune processes in the lymphoid tissue associated with the mucosal membranes. A critical objective of mucosal immunization is the identification of an antigen delivery vector capable of ensuring optimal vaccine efficacy. The authors of this article have conducted extensive research on the probiotic properties of enterococci over an extended period. They employ a safe and beneficial probiotic strain, Enterococcus faecium L3, as a delivery vector for vaccine antigens. Initially, the gene encoding the pathogenicity factor Bac, derived from group B streptococci (Streptococcus agalactiae), was successfully integrated into the genome of the probiotic strain E. faecium L3. Intravaginal, oral, and intranasal mucosal immunization methods utilizing the L3-Bac+ probiotic, which expresses antigenic determinants of pathogenic streptococci, were found to confer protection against bacterial infection in laboratory animals. Subsequently, recombinant technologies were refined, leading to the development of a universal method for incorporating a region of interest from the gene into the structure of the major pili protein gene of E. faecium L3. Using this technology, candidate vaccines against various infections, including Streptococcus pneumoniae, influenza A virus, and SARS-CoV-2 following the onset of the Covid-19 pandemic, have been obtained and tested. In this study, alongside the presentation of our own data, the challenges associated with utilizing recombinant probiotic bacteria as vectors for vaccine antigen delivery are discussed.

Relevance. Modern identifying potency (immunogenicity) of diphtheria toxoid tests are based on determining immunized animals resistance for administration challenge toxin or evaluation of protective antibodies level in serum. In Russia to assess the potency of diphtheria toxoid (DT) the challenge lethal method has been used for more than 60 years, challenge is based on determination of potency via its possibility to defend immunized animals from lethal doses of diphtheria toxin. This method is used as «golden standard». Last decade European Union Regulatory politic is headed to reduce of using animals in pharmaceutical practice, "The Three Rs" approach. In frameworks of this approach alternative methods of evaluating immunogenicity DT were purposed, particularly, intradermal challenge method. Within this test the potency of diphtheria toxoid is evaluated by its possibility to protect immunized animals from intradermal administration of diphtheria toxin. In the production of a number of foreign vaccines intradermal challenge test is used for assessing potency.

Aim. Comparative characteristics of methods of lethal challenge test and intradermal challenge tests to determine the potency of diphtheria toxoid in combined vaccines and toxoids made in Russia.

Materials and methods. Materials of domestic and foreign manufacturers were used in the work: combined vaccines for diphtheria prevention, diphtheria toxins, reference-vaccine. The determination of the potency of diphtheria toxoid was carried out on guinea pigs by pharmacopoeias methods: lethal challenge test and intradermal challenge tests.

Results. To assess the potency of diphtheria toxoid using, a technique was used in accordance with WHO recommendations; for this, guinea pigs similar in sensitivity to diphtheria toxin to Dunkin Hartley pigs were selected. The suitability of the diphtheria toxin used in Russia for determining the potency of diphtheria toxoid by the method of intradermal challenge test was assessed when evaluating the effectiveness of vaccines for the prevention of diphtheria. Comparative tests of the intradermal challenge tests and lethal challenge tests were carried out to determine the potency of diphtheria toxoid.

Conclusions. The conducted studies have demonstrated the fundamental possibility of using the intradermal challenge tests to assess the potency of diphtheria toxoid. However, for a number of factors, such as the variability of results, the number of animals, etc., the intradermal challenge tests is inferior to the method of lethal challenge tests in assessing the potency of diphtheria vaccines in routine practice.

Relevance. Molecular surveillance, aimed at obtaining up-to-date information on the genetic variants of pathogens circulating in the studied region, is an important element of the surveillance of natural focal infections (NFIs). The Stavropol Territory is one of the main recreational regions in the Russian Federation; it is endemic for a number of NFIs, including: Crimean-Congo hemorrhagic fever (CCHF), Q fever, tularemia, Lime disease, etc.

The aim of the work is is genomic profiling of NFIs causative agents circulating in the Stavropol Territory in 2016-2021.

Materials and methods. Microbial strains and samples of field and clinical material containing genomic DNA/RNA of pathogens were used as material for the study. Genetic typing of strains and isolates of DNA/RNA NFIs causative agents was performed by MLVA (Francisella tularensis and Coxiella burnetii) and genome fragment sequencing (Crimean-Congo hemorrhagic fever virus, West Nile virus, orthohantaviruses, Borrelia burgdorferii s.l., Ricckettsia sp.).

Results. As a result of molecular genetic typing in the ST in 2016-2021 confirmed circulation of strains of F. tularensis of genetic subgroups B.I, B.III, B.VI, genetically identical strains of C. burnetii (VNTR-профиль 4-6-6-4-7-6-3-12-3-11), rickettsia belonging to 5 species: R. raoultii, R. aeschlimannii, R. slovaca, R. massiliae, R. helvetica , Borrelia belonging to the species: B. afzelii, B. garinii, B. miyamotoi, B. bavariensis, B. lusitaniae, B. valaisiana, RNA isolates of the CCHF virus of the Europe-1 and Europe-3 genetic lines, Tula orthohantaviruses, West Nile virus genotype 2. For the first time on the territory of the CT, in insectivore lung samples, RNA isolates of orthohantavirus genetically close to Camp Ripley virus (RLPV) were detected.

Conclusions. New data have been obtained on the distribution of genetic variants of NFIs causative agents in the S, also in the recreation areas. Genetic structure of the population of NFIs causative agents in the ST in 2016-2021 did not change significantly, which indicates the relative stability of the natural foci of NFIs in the region.

Relevance. Cancer therapy forms a temporary immunosuppressive state, which determines an increase in the frequency and severity of infectious diseases. Vaccination is a highly effective and safe way to protect against infection, but people with immunodeficiency have risks of inefficiency and complications. To substantiate the need for immunoprophylaxis in cancer patients after therapy, it is important to understand the preservation of their specific response after previous vaccinations.

The aim of the study was to assess the safety of antibodies to vaccine–controlled infections in children with oncological diseases after therapy

Materials and methods. The safety of antibodies to vaccine-controlled infections was studied in 3 groups: 1 -in patients with oncological (n=62); 2-in the group (n=43) withoutoncological diseases, but who received immunosuppressive (IST) and/or polychemotherapy (PCT) and/or hematopoietic stem cell transplantation (HSCT), and 3– in healthy children (n=31 – comparison group). The concentration of antibodies was determined by the ELISA method. The minimum protective level was considered to be the amount for measles ³0.18 IU/ml, rubella - ³25 IU/ml; hepatitis B - ³10 IU/ml; diphtheria – 0.03 IU/ml and higher. The coefficient of positivity, estimated as protective against mumps, was ³1.0.

Results. It was found that from 41.7% to 93.7% of children with cancer lose post-vaccination immunity to the studied vaccine antigens. The number of children who retained the protective level of antibodies in groups 1 and 2 was significantly less than in the comparison group. There were no significant differences in the level of those protected from diphtheria and rubella. The maximum effect on the loss of antibodies is provided by the performed HSCT. For diphtheria and rubella antibodies, the differences are not pronounced. The possible connection of genetic breakdowns in 35 examined children with oncological diseases and the safety of antibodies was analyzed. It turned out that in the presence of chromosomal deletions, antibodies to measles were lost in 100% of cases and to diphtheria in 75%, which was different from other chromosomal abnormalities.

Conclusion. The safety of antibodies in patients with a history of cancer is influenced by the presence of HSCT in therapy, the type of genetic breakdown, as well as the peculiarity of the vaccine antigen. Children with oncological diseases, as well as with non-oncological ones, but who have received HSCT therapy, should be vaccinated again against vaccine-controlled infections, despite the indication of the presence of vaccinations before therapy.

Relevance. Antibiotic resistance of microorganisms can contribute to the chronicity of the inflammatory process, lead to an increase in the cost of treating patients and make it difficult to eradicate the pathogen. Patients with cystic fibrosis constantly require medical supervision, regular visits to medical institutions, and therefore there is a high risk of infection with nosocomial antibiotic- resistant strains. In addition, the necessary intake of antibacterial drugs provides an advantage for the reproduction of resistant microorganisms.

Aim. Comparison of the frequency of detection of antibiotic resistance determinants in oropharyngeal swabs in children with cystic fibrosis and conditionally healthy children using molecular biological methods.

Materials and methods. A PCR study of oropharyngeal discharge from 100 children with cystic fibrosis and 100 children from the control (healthy comparison subject) group was performed. Genetic antibiotic resistance locus: metallo-b-lactamases of the VIM, IMP and NDM groups; carbapenemase genes of the KPC and OXA-48 groups; extended-spectrum beta-lactamase genes of the CTX-M group and the mecA gene were detected by polymerase chain reaction (PCR) with hybridization-fluorescence detection.

Results and discussion. As a result of the analysis, a statistically significant increase in the frequency of detection of genetic determinants of antibiotic resistance in the microbiota of the oropharyngeal discharge in children with cystic fibrosis was found compared with healthy children (p<0.001). The chances of detecting antibiotic resistance loci in the discharge of the oropharynx among children with cystic fibrosis are 38.5 times higher than among healthy children (95% CI: 5.1-289.5). In 28% of children with cystic fibrosis, DNA of the genetic determinants of antibiotic resistance was detected in the microbiome of the discharge of the oropharynx. A high percentage of the presence of genetic determinants of antibiotic resistance may be the reason for the ineffectiveness of antibiotic therapy.

Conclusion. Due to the high occurrence in the microbiome of the oropharyngeal discharge of patients with cystic fibrosis of genetic antibiotic resistance locus that are of particular clinical and/or epidemiological significance, and the high risk of the spread of antibiotic-resistant strains outside medical institutions, it is necessary to include this group of patients in regular epidemiological monitoring.

Relevance. Currently, studies of the prevalence of antibiotic resistance and its genetic characteristics are focused primarily on the adult population, although infection with multiple drug infection has been registered as etiological agents of a general infection in obstetric and gynecological and pediatric institutions. The study of the prevalence of genetic determinants of antibiotic resistance is an important area of scientific research.

Aim. To analyze the results of the studies carried out to identify the genetic determinants of antibiotic resistance of enterobacteria isolated during microbiological monitoring in the perinatal center.

Materials and methods. The genetic profile of antibiotic resistance was studied in ESBL-producing strains isolated from 45 women and 35 children examined at the departments of the Federal State Budgetary Institution «NII OMM» of the Ministry of Health of Russia. To determine the determinants of antibiotic resistance, 80 non-duplicate strains of 7 species of the Enterobacteriaceae family were studied. DNA of bacterial cells was isolated from a daily culture of microorganisms using the PROBA-NK kit, detection of the tem, ctx-M-1, shv genes; oxa-40-like, oxa-48-like, oxa-23-like, oxa-51-like, imp, kpc, ges, ndm, vim were carried out using the diagnostic kit «BacResista GLA» on the detecting amplifier DT-48 (DNA -technology, Russia). To assess the statistical significance of differences in the frequency of occurrence of genes, Pearson's c2 test with Yates' correction was used.

Results and discussion. When analyzing the results of studies on the molecular genetic detection of antibiotic resistance determinants, which we conducted in 2022, it was found that 8 genovariants were found in bacterial strains isolated from patients of the departments of the Research Institute of OMM in Yekaterinburg, providing resistance to beta-lactam antibiotics. The dominant genome, as in 2021, remains blaCTX-M-1, found in 29 cases. The blaTEM gene was identified both in association with other genes and as a single variant in Escherichiae coli and Klebsiella pneumoniae strains. Of the eight strains of K. pneumoniae, 4 were found to have three antibiotic resistance genes blaCTX-M, blaTEM, blaSHV, strains with a genetic profile of blaCTX-M, blaTEM, blaSHV, blaNDM were isolated once; and blaTEM, blaSHV, blaKPC. In one strain of K. pneumoniae, phenotypically showing resistance to AB, no genetic determinants of AB resistance were found. In addition to resistance to beta-lactam antibiotics, the strains demonstrate resistance to such groups of antibacterial drugs as fluoroquinolones, phosphonic acid derivatives (fosfomycin), and aminoglycosides. The data obtained indicate that the intestines of newborns during their stay at the stationary stage of nursing in some cases are colonized by strains of enterobacteria with multidrug resistance. Consequently, children are a reservoir of resistant microorganisms and can be sources of pathogens of infectious diseases in families and children's organized groups.

Background. Individuals who were vaccinated against seasonal influenza or had a history of pneumococcal vaccination were found to be less likely to become infected and tolerate COVID-19 more easily. However, it has not been sufficiently studied how vaccination against these infections, carried out during the pandemic period, can affect the incidence of COVID-19.

Aims. The purpose of the investigation: to study the effect of vaccination against influenza and pneumococcal infection carried out during the pandemic of a new coronavirus infection on the susceptibility and course of COVID-19 in healthcare workers.

Materials and methods. In August- Setempber 2020, after the first rise in the incidence of COVID-19, out of 547 employees (aged 18 to 70 years) of a medical organization (MO), 266 (49%) were vaccinated against influenza (group II, n = 98), pneumococcal infection (group III, n = 60) and combined vaccination (group IV, n = 108), while 281 (51%) remained unvaccinated (group 1). Follow-up period: from September 2020 to March 2021 with the registration of the incidence of acute respiratory infections (ARI) according to primary medical records and the use of PCR methods for SARS-CoV-2, epidemiological and statistical analysis.

Results. Two months after the start of the study, the proportion of cases of COVID-19 in the 1st group (unvaccinated) was 5% versus 1% in the 4th group (persons vaccinated with two vaccines), after 4 months – 15% and 5%, respectively, and at the end of observation (166 days) – 16% and 8%, respectively. That is, among unvaccinated individuals, the risk of getting COVID-19 was higher by HR = 2.1 [95% CI: 1.0÷4.7] times. The time between the start of observation and a positive test for COVID-19 in study participants was significantly higher in the 4th group compared to the group I: 106 [60–136] days versus 47 [17–75] days. The distribution of patients with COVID-19 according to the severity of viral pneumonia showed that in unvaccinated patients in most (64%) cases, pneumonia had a moderate to severe course, while in the 4th group of patients with combined vaccination in 100% of cases, mild (p = 0.04 for the entire sample).

Conclusions. During the COVID-19 epidemic rises, vaccination against respiratory infections remains relevant, reducing the number of cases, the severity of the coronavirus infection and preventing the occurrence of co-infections.

Relevance. The decrease in the number of cases of invasive diseases caused by N. meningitidis, S. pneumoniae, H. influenzae and in the world has been associated with measures against the spread of the 2019 coronavirus disease (COVID-19).

Aim. Presentation of the epidemiological features of purulent bacterial meningitis (PBM) in the Russian Federation at the present stage.

Materials and methods. On the basis of the Russian Reference Center for Monitoring Bacterial Meningitis (RCMC), an in-depth personalized system for recording PBM cases has been established. Since 2010, all territories of the Russian Federation have been included in the monitoring system. In 2022, the RCMC received information on 1596 cases of PBM. The descriptive-evaluative epidemiological method was used in the work: a retrospective analysis.

Results. The increase in the incidence of a generalized form of meningococcal infection (GFMI), which began in 2017, was recorded in 2018 and 2019, but in 2020–2021 growth was interrupted: the indicator dropped sharply, amounting to 0.26–0.21 per 100 thousand of the population, which is most likely due to the disunity of the population as a result of measures aimed at combating the new coronavirus infection. Measures to combat COVID-19 were canceled in 2021, and already in 2022 the incidence rate of GBM increased by 1.4 times, while the GFMI by 2 times, amounting to 0.44 per 100 thousand of the population. A sharp decrease in the incidence of PBM caused by S. pneumoniae and H. influenzae in 2020-2021 was replaced in 2022 by an increase in the incidence of pneumococcal meningitis, however, the incidence of meningitis caused by H. influenzae remained at the same level.

Conclusion. Continued monitoring of the incidence of PBM and the properties of the pathogen are extremely important tasks in order to identify risk groups and areas for the timely optimization of vaccination measures, given that the three infections that cause bacterial meningitis are vaccine-controlled, and vaccination is recognized as the most effective measure to combat meningococcal, pneumococcal and hemophilic infections.

Relevance. The global strategy for cervical cancer elimination includes the active implementation of primary, secondary and tertiary prevention programs. In the Russian Federation, screening for the detection of malignant neoplasms of the cervix is carried out while women contact specialists, as well as an organized procedure during preventive medical examinations of the certain groups of adults. The study of the population structure of circulating human papillоmavirus (HPV) types, and evaluation of the effectiveness of the recommended diagnostic models will improve the direction of the fight against cervical cancer and introduce optimal preventive solutions.

Aim. Retrospective analysis of screening effectiveness for the detection of malignant neoplasms of the cervix, carried out during the medical examination in one institution of Moscow.

Materials and methods. The study examined 1068 women aged 20 to 81 years (M = 37.82, Me = 35, IQR 27–47 years) from one institution in Moscow over a 5-year follow-up period (2017–2021). The screening was based on the co-testing model: liquid-based cytology with Papanicolaou staining and classification according to the Bethesda system and quantitative Real Time HPV-test with determination of the 14 HPV DNA types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68).

Results. The prevalence of the 14 HPV oncogenic types was 14.87% (95% CI: 12.86–17.13%), the most common were 16 (16.98%), 31 (14.47%), 52 (13.21%). The study determined HPV types with the highest relative risk of persistence: 33, 58, 45, and 52 (p < 0.005). The frequency of HPV detection depended on the age of the examined women and was the highest in the age group of 20–29 years (25.58%). The baseline prevalence was 11.82% (95% CI: 9.98–13.94%). 6 HSIL cases associated with HPV types 16 and 31 were identified. 4/6 were in women under 30 years. The probability of intraepithelial lesions of the cervix increased with an increase of HPV DNA concentration: 23.65% and 66.67% with a viral load of 4.0–6.0 lg copies per 105 human cells and > 6.0 lg copies per 105 human cells, respectively.

Conclusions. The study confirmed the great value of HPV- test in screening for the detection of malignant neoplasms of the cervix during the medical examination of the certain groups of adult population, taking into account the advantages of typing and quantitative determination of HPV DNA, as well as the need to consider lowering of the recommended age for the start of HPV-testing.

Relevance. Hepatitis B virus (HBV) is one of the most common viral infections affecting people worldwide and can lead to chronic hepatitis, cirrhosis and hepatocellular carcinoma. Currently 3% of the world's population are infected with hepatitis B virus and are at risk of developing life-threatening liver disease. Immunological and molecular biological methods of detection of HBV are currently used in laboratory diagnostics. The polymerase chain reaction (PCR) is currently the most sensitive method for the detection and quantification of HBV. HBV DNA quantification is widely used to monitor the antiviral treatment of HBV infection.

Aim. To develop a real-time PCR kit for the quantification of HBV DNA.

Materials and methods. A total of 200 plasma and serum samples positive and negative for HBV were used in the development. The performance of the developed kit was compared with the use of other commercially registered HBV diagnostic kits in Russia. Additionally, the nucleotide sequences of all existing virus genotypes analysed for the selection of primers using GeneBank system.

Results and discussion. Comparison analysis of the results of quantitative determination by real-time PCR in 200 clinical serum and blood plasma samples showed that the diagnostic sensitivity of the developed kit was 100% and specificity 100%. The primers developed specific to the POL gene region. The kit is capable of detecting all types of virus genotypes.

Conclusions. The developed reagent kit allows detection of hepatitis B virus and determination of its quantity within 70 minutes. In addition to a large number of genotypes and subgenotypes, the virus is characterized by mutational changes in the genome, which complicates its diagnosis and, as a consequence, the ongoing therapy with drugs. Conservative regions for primer and probe selection taken into account in the development, and the sequencing results obtained are applicable to all HBV genotypes. The reagent kit is designed to monitor HBV infected patients and will allow the analysis of different HBV viral loads.

Relevance. Thanks to decisions taken at the national level, many countries have managed to significantly increase coverage with preventive vaccination and reduce mortality from vaccine-preventable diseases. However, the COVID-19 pandemic has recaptured the relevance of organizing mass vaccination. Based on the current epidemiological situation, characteristics of the population, peculiar features of infrastructure, available resources in individual country, and individual city, various organizational vaccination solutions have been developed and implemented. The Moscow-based experience of vaccinating against influenza at mobile vaccination sites near the Moscow metro stations in 2016 became the starting point in the development of new organizational forms and technologies for mass vaccination in a megapolis, that have been successfully adapted to the new conditions of the COVID19 pandemic.

Aims. is to summarize foreign and Russian (exemplified by Moscow) experience in organizing mass vaccination.

Material and methods. The study is based on the publication search results in Google and PubMed. The authors selected materials published in 2017– 2023. The implemented analysis of the long-term dynamics in the influenza incidence in the Russian Federation, the Central Federal District (CFD) and Moscow was based on data of the Federal State Statistical Observation Form No. 2 «Information on infectious and parasitic diseases» for 2013–2019.

Results and discussion. The analysis of foreign experience shows that the development and implementation of new forms of mass vaccination cannot become a "standard project". In each region of the world, it is organized with due regard to the local economic, legal, social, medical, organizational and even cultural conditions. Vaccination of the population against influenza at mobile vaccination sites near the Moscow metro stations contributed to a 42.3% decrease in the incidence of influenza (from 24.6 in 2016 to 14.2 per 100,000 population in 2017). In 2019, the incidence of influenza in Moscow was 28.8% lower than the CFD one and 62.2% lower than the Russian rate. The recognized successful experience of deploying mobile vaccination sites near the metro stations has been significantly expanded to control the COVID-19 pandemic with mobile teams, vaccination sites in shopping centers, etc.

Conclusion. The conducted research and literature data substantiate the deployment of additional vaccination sites to ensure the necessary coverage with vaccination within a short period of time.

Pneumococcal infection remains a significant global health problem, and vaccination is the main measure for its prevention. To date, the period of use of pneumococcal conjugated polysaccharide vaccines in Russia exceeds 14 years, and 13-valent conjugated polysaccharide pneumococcal vaccine (PCV13) - more than 10 years. During this time, extensive experience has been accumulated in the use of this type of vaccines, and many studies have been carried out to evaluate their effectiveness and safety.

The purpose of this review is to summarize the experience of using PCV13 in Russian Federation with an assessment of its epidemiological and clinical effectiveness. A search was made for scientific publications devoted to the study of the epidemiological efficacy, the safety as well as cost-effectiveness of PCV13 use in Russian Federation. The review included original studies published in Russian journals. The results of the studies carried out indicate the efficacy and safety of PCV13 for both adults and children. The effectiveness of immunization of children at risk (premature, suffering from congenital pathology, having chronic diseases and often ill) was demonstrated, the need and safety of the timely start of vaccination (from 2 months of age) of newborns was shown, the possibility of its combination with immunization against other infections within the framework of the national vaccination schedule, the importance of following the recommended vaccination schedule in accordance with the age of the child. The effectiveness of vaccination of adults suffering from chronic diseases has been shown both in terms of preventing the aggravation of the course of the underlying pathology and reducing the risk of pneumonia. Positive experience has been gained in immunizing adults from occupational risk groups - medical workers, conscripts and persons exposed to a harmful production factor and having occupational lung diseases. The conducted studies have shown a high cost-effectiveness of PCV13 vaccination, however, with any changes in price and epidemiological parameters, it is necessary to clarify the economic feasibility of vaccination under the changed conditions. Taking into account the positive experience gained in immunization, it seems appropriate to further maintain a high level of vaccination coverage of the child population, expanding risk groups among the adult population subject to vaccination against pneumococcal infection within the framework of the National Immunization Schedule, taking into account its epidemiological, clinical and economic efficiency.

Relevance. Health care-associated infections (HAIs) are one of the global problems of modern healthcare with a negative trend in the growth of this pathology throughout the world, which is due to a complex of reasons, among which the resistance of pathogens of hospital infections to antimicrobials is important, as well as gaps in organization of epidemiological surveillance due to a number of objective and subjective factors (complication of technologies and expansion of the practice of invasive medical interventions, turnover and shortage of personnel in medical institutions, etc.).

The purpose of the work is to study the experience of organizing measures for the prevention of HCAI from the standpoint of a systematic approach in Russia and in foreign countries that have the best practices in this area. The purpose of the work is to study the experience of organizing measures for the prevention of HCAI from the standpoint of a systematic approach in Russia and in foreign countries that have the best practices in this area.

The results are based on the study of the basic principles of the system approach, its tools, functional organization and universalization, the use of a comprehensive analysis in relation to different areas of medical activity and types of medical care, the sequence of development and implementation of new methods in Russian and foreign experience in the implementation of epidemiological surveillance for HCAI. Problems in the field of organization and practical implementation of preventive measures to prevent the occurrence of HCAI have been identified, and urgent tasks for improving the epidemiological safety of medical activity have been identified.

Conclusion. Differences were noted in approaches to the prevention of HAIs in Russia and abroad, concerning the resource provision of molecular biological monitoring of HAI pathogens, as well as the features of teamwork, targeted communication in medical teams and in explanatory work, as well as the implementation of training programs for relatives to care for patients with HAI. Measures are proposed to increase the commitment of medical personnel and collectives in general, other employees of medical organizations to epidemiologically safe skills in their professional activities, to develop patient education programs for personal prevention of HCAI.

Analysis of scientific publications is revealed that HIV transmission been present among humans for centuries or thousand years. This evidence had been proved by molecular and genetic methods. Additionally, to molecular methods the fact been proved by the presence in humans of a perfect genetic defense against HIV. There is a long co-evolution between humans and their pathogens needed to develop genetic defense mechanisms.