Relevance. During the pandemic of the new coronavirus infection (COVID-19), one of the most vulnerable and actively involved in the epidemic process categories of the population were medical workers. The study of the incidence of COVID-19 among medical workers, risk factors for infection and safety measures is an important area of research in modern conditions. The aim of the study is to assess the prevalence of COVID-19 among employees of medical organizations and occupational risk factors for infection in order to develop proposals for corrective measures. Materials and methods. To study the incidence of COVID-19 among employees of medical organizations, an anonymous online questionnaire developed by the authors was used, which was posted on the Google platform and distributed during the first wave of the pandemic among employees of medical organizations in several regions of the Russian Federation through corporate e-mail or specialized online resources adapted for health workers. The survey involved 1,872 medical workers of different genders, ages, positions and work experience. Results and discussion. Among the survey participants, 161 employees have already had a new coronavirus infection. In the majority (64.0%) of them, the disease occurred in the form of acute respiratory infection, in 28.6% - interstitial pneumonia, in 7.4% only the fact of isolation of the SARSCoV-2 antigen without clinical manifestations of infection was documented. The most affected contingents were secondary and junior medical personnel, mainly hospital staff. The likelihood of infection in the workplace was increased by factors such as providing care to patients with confirmed COVID-19, participating in procedures related to aerosol generation, working with biomaterials of patients with COVID-19, contact with surfaces in the environment of a COVID-19 patient, ignorance of infectious safety issues due to lack of instruction before admission to work. When assessing the efficiency of personal protective equipment (PPE) when they are used in the process, it was found that the highest value for the prevention of infection COVID-19 had a PPE for face protection, respiratory and eye, and hand hygiene. At the same time, many employees are faced with the problem of an insufficient number of protective equipment in the workplace. When assessing the availability of SARS-CoV-2 testing to employees, it was found that only 77.4% of survey participants had the opportunity to be tested for coronavirus infection in a timely manner. Conclusion. Thus, for more effective protection of employees of medical organizations, it is necessary to have a sufficient number of personal protective equipment, especially for the face, respiratory organs and vision, the availability of hygienic hand treatment during work, regular instruction on infectious safety, using interactive forms of training, and the organization of screening examinations of previously unvaccinated and unvaccinated employees.

Background. The ongoing COVID-19 pandemic in the world and in Russia remains the main event in 2020. A comprehensive study of the patterns of development and manifestations of the epidemic process of the new coronavirus infection COVID-19 is an urgent line of research. One of the important aspects of the fight against COVID-19 is the study of population immunity to the SARS-CoV-2 virus in order to assess seroprevalence and the formation process of post-infectious humoral immunity to SARS-CoV-2, forecast the development of the epidemiological situation, identify the features of the epidemic process, as well as planning measures for specific and non-specific disease prevention. The aim of the research is to determine the level and structure of population immunity to SARS-CoV-2 among the humans of the Irkutsk region during the COVID-19 epidemic. Materials and methods. As part of the Rospotrebnadzor project to assess population immunity to SARS-CoV-2 in the population of the Russian Federation, research is being conducted among the population of the Irkutsk region in the periods from 06/23/2020 to 07/19/2020 (stage 1), from 09/16/2020 to 09/25/2020 (Stage 2) and from 12/07/2020 to 12/18/2020 (stage 3), taking into account the reacted one recommended by the WHO. The content of antibodies to SARS-CoV-2 was determined by ELISA using a set of tests for human serum or plasma for specific immunoglobulins of class G to the nucleocapsid of the SARS-CoV-2 virus produced by FBUN GNCPMiB Rospotrebnadzor (Obolensk). The results of a research of the humoral immunity of volunteers show that during the period of an epidemic rise in the incidence of COVID-19 in the Irkutsk region, a low level of seroprevalence was formed (stage 1 – 5.8 ± 0.5%, stage 2 – 12,1 ± 0,7%), and in conditions of a long-term maximum increase in the incidence rate ¬– 25,9±1,0% (stage 3). A significant proportion (stage 1 – 81,2±3,2%, stage 2 – 90.9 ±1,9%) of asymptomatic forms of infection characterize the high intensity of the latently developing epidemic process in the first two stages. High levels of IgG in reconvalescents of COVID-19 persisted for an average of 3 to 4.5 months. Conclusion. The results of assessing the population immunity to the SARS-CoV-2 virus in the population of the Irkutsk region indicate that the seroprevalence level at the 3rd stage of the research was 25.9%. After the disease, on average, 41.6% of persons did not detect antibodies. The results obtained should be taken into account when organizing preventive measures, including vaccination, and predicting morbidity.

Relevance. The experience of combating rabies in Europe has shown that the tactics of preventive measures in mountains must be modified. At the beginning of the 21st century, the spread of fox rabies into the previously rabies-free mountain areas in southern Siberia was noted. The aim is to trace the spread of rabies in the Altai Mountains after the introduction of the virus. Materials and methods. A retrospective descriptive study using GIS was carried out. For mapping, information on 55 laboratory confirmed cases of rabies in the Altai Republic, QGIS 3.16.0, ArcMap 10.8.1, ArcScene 10.8.1 programs and an electronic landscape-geographical maps "Natural Earth" and "Open street map" were used. The spatial-temporal distribution of rabies was compared with changes in postexposure prophylaxis (PEP). Results. In 2007, rabies was detected for the first time since 1948 in the Altai Mountains. Wild animals (fox, wolf, badger) accounted for 52.7% (95% CI 39.5–65.9). Most of the cases were found in the foothills and river valleys at an altitude of less than 1,000 meters above sea level and only 16.4% (0.0–26.2) – in areas with heights from 1,000 to 2,000 m. Rabies was not recorded in the mountains above 2,000 m. Two different directions of the virus introduction are assumed: from the forest-steppe plains of the Altai Territory (Russia) and from the mountainous steppes of Mongolia. In 2007–2019 the annual number of patients seeking medical attention after animal bites increased by 86%. A correlation between the animal case number in different areas and the average annual PEP was noted (r = 0.649, p = 0.03). 4. Conclusions. Features of the fox rabies spread in the Altai Mountains allows to use the experience of fighting this disease in the mountainous regions of Central Europe.

Background. Acute respiratory viral infections (ARVI) and pneumococcal infections (PI) annually cause great damage to the health and working capacity of the population, and lead to economic losses for employers and the state. Aim. To study the impact of influenza and PI vaccination coverage on morbidity of ARVI and community-acquired pneumonia (CAP) of the morbidity of population in Central administrative district (CAD) of Moscow. Material and methods. The analysis of official data on monitoring of morbidity from ARVI and CAP was carried out, and information on vaccination of the population against influenza and PI for 2012–2018 was used. Results. In 2018 ARVI accounted for 95.2% of infectious morbidity and the incidence rate was 29853.5 per 100 ths population. Over the period from 2012–2018, the incidence of ARVI and influenza gradually decreased by 2016, but in 2017 the incidence of ARVI was increased to the level of 2012 (+25.3%) however influenza was decreased (-40.9%). In 2018, the incidence of ARVI in adults remained at the level of 2017, and in children there was a decrease (-16.9%). The incidence of influenza in 2018 decreased in both adults (-65.4%) and children (-63.9%). During 2012–2018 the incidence of CAP had a persistent tendency to increase. The coverage of influenza vaccination in CAD population of Moscow has increased annually since 2012 and in 2018 reached 85.5% of children 0–17 years old and 65.5% of adults 18 years and older, and against PI – 46.3% of children and 2.6% of adults. Conclusion. The epidemic circulation of ARVI and influenza had a significant impact on the morbidity of CAD population of Moscow in 2012–2018. Annual vaccination of the population lead to decreasing of influenza incidence but the incidence of pneumonia tended to increase and need to improve prevention.

Relevance. According to US scientists, the percentage of people who do not know about their positive status is 20% of all people living with HIV. Moreover, this group provides 49% of new infections. Therefore, it can be assumed that information about HIV status has a significant epidemiological effect. Aim. To assess the change in risk behavior of HIV-infected persons after informing about the diagnosis and the frequency of occurrence of nonspecific symptoms of HIV infection. Materials and methods. For information on changing the behavior profile was developed, consisting of three sections. The first and third sections are aimed at elucidating the characteristics of sexual and drug behavior from the moment of probable infection to the moment of diagnosis, in comparison with the time period from the moment of reporting the diagnosis to the present. The second section of questions is aimed at determining the frequency of occurrence of nonspecific symptoms of early HIV infection. In the survey agreed to participate in 79 HIV-infected patients. The reliability of the results obtained was determined using the Wilcoxon Sign Test. Results. The message of the diagnosis of HIV infection contributed to the desire to abandon the systematic use of intravenous drugs. The proportion of people who denied drug use increased from 13 to 65% (p < 0.05). The number of people infected intensively (30 and more doses / month) using drugs has more than halved – from 38 to 17% (p < 0.05). The number of people denying drug use in groups increased from 10 to 45% (p < 0.05). From 55 to 12% (p < 0.05), the proportion of people who pass their syringe (needle) to another person to inject drugs has decreased. The number of persons who noted the presence of more than 5 partners per year after diagnosis decreased three times (p < 0.05). Only 23% of the respondents did not present any complaints in the period preceding the detection of HIV infection. Symptoms of acute respiratory disease marked 48%, 37% had fever, and other non-specific clinical manifestations of HIV infection. Conclusion. Communicating a positive HIV status to a patient reduces the likelihood of HIV transmission by drugs by 3–4 times and sexually by 2–3 times by changing risky behavior. Nonspecific symptoms of an acute viral disease before the detection of HIV infection were recorded in 48% of cases.

Relevance. Age-related and occupational aspects of SARS-CoV-2 seroprevalence in healthcare workers are not well understood. Aims: Conduct a selective study of seroprevalence to the SARS-CoV-2 virus among 348 medical workers of 10 medical organizations in Kazan: seven multidisciplinary hospitals that have been re-profiled to provide medical care to patients with coronavirus infection, an ambulance station, a medical organization that carries out outpatient activities and a specialized clinic. Materials and methods. Among those surveyed on a professional basis, the groups «Doctors», «Nurses», «Junior medical personnel», «Other medical workers» were identified. The age structure of seroprevalence was studied in groups of 18–29, 30–39, 40–49, 50–59 and 60–69 years. For the determination of IgG, a solid-phase ELISA was used. Results. The proportion of medical workers (MR) of various medical organizations in Kazan seropositive for IgG to the SARS-CoV-2 virus is 16.4%. The wide variation in the seroprevalence value of MR groups of different medical organizations (3.3–30.8%) may indicate a different level of effectiveness of anti-epidemic measures in these institutions. The maximum rate was noted in the age groups – 18–29 years (21%) and 60-69 years (18.2%). According to the professional criterion, a comparable level of seroprevalence is shown for the categories «Doctors» and «Nurses» with a wide variation in indicators in professional groups, depending on a particular medical organization. The obtained results indicate the presence among medical workers who have suffered or have an asymptomatic course of infection caused by SARS-CoV-2, and confirm the relevance of further serological monitoring in medical organizations of various profiles. The results of serological monitoring, taking into account age and professional aspects, can serve as the basis for adjusting preventive measures on the basis of individual medical organizations, and taking into account the recommendations of Rospotrebnadzor and the selection of contingents for vaccination against SARS-CoV-2. Conclusions: For the MR of various medical institutions in Kazan, the seroprevalence for antibodies to the SARS-CoV-2 virus is 16.4%; Age aspects affect the level of seroprevalence in MR; The obtained results indicate the presence of persons among MR who have had or have an asymptomatic course of infection caused by SARS-CoV-2, and confirm the relevance of further serological monitoring in medical organizations of various profiles.

Relevance. The need to increase vaccination coverage in order to eliminate measles in Russia and increase public confidence in vaccination requires constant monitoring of the quality of vaccines used for measles prevention. Aim. Analysis of laboratory quality parameters of commercial series of vaccines for measles prevention produced by JSC NPO Microgen, issued from 2015 to 2020, in comparison with the series issued in the period from 2002 to 2009. Materials and methods. The object of the study was a live measles culture vaccine and a live mumps-measles culture vaccine produced by JSC «NPO «Microgen». The quality analysis of vaccines was carried out according to the consolidated production and control protocols of 422 series of measles vaccine and 855 series of mumps-measles vaccine issued in 2015-2020, and 1043 series of measles vaccine and 902 series of mumpsmeasles vaccine issued in 2002-2009. Results and discussion. It is shown that the quality of the studied vaccines is stable during 16 years of monitoring. The sensitizing properties of both vaccines significantly decreased during the last 6 years of follow-up due to a decrease in the residual content of the antibiotic in the vaccination dose to less than the detection limit, as well as due to the low content of heterogeneous protein (bovine serum albumin). Conclusion. The quality of domestic vaccines for the prevention of measles and mumps meets who requirements; it is characterized by stability over 16 years of follow-up and minimal sensitizing properties. Information about the quality of domestic vaccines for the prevention of measles is an important argument for countering the antivaccination movement, which is a global problem and is recognized by who as one of the most important threats to the health of the world's population.

Relevance. The COVID-19 pandemic has led to significant overloads in the work of health systems in many countries, a shortage of beds and staff, which contributes to a decrease in adherence to measures to prevent and control nosocomial infections, which can significantly worsen the course of viral pneumonia. Aim. To assess the possibility of the formation of hospital strains of multidrugresistant microorganisms in hospitals repurposed to provide medical care to patients with COVID-19. Materials and methods. The study included patients with severe and moderate forms of COVID-19 (ICD codes U07.1, U07.2), who were admitted to two large hospitals repurposed for the treatment of this infection. The data of microbiological studies of the biomaterial associated with the respiratory tract (sputum, bronchoalveolar lavage, tracheal aspirates) obtained from 1101 patients from May to January 2021 were analyzed using a combination of molecular genetic methods (RAPD-PCR, detection of integrons and the carbapenemase gene bla NDM.), and molecular typing of carbapenem-resistant strains of Klebsiella pneumoniae and Acinetobacter baumannii was carried out. Results. It was found that carbapenem resistant gram-negative bacteria predominate in the structure of the nosocomial microbiota of the respiratory tract of patients with COVID-19 in both hospitals. Based on molecular typing made the wide distribution of several genetic lines of integron-positive carbapenem resistant Klebsiella pneumoniae and Acinetobacter baumannii was detected. Conclusions. The COVID-19 pandemic has exacerbated the spread and circulation of bacteria with multiple antibiotic resistance in hospitals. This study has demonstrated the possibility of the formation of hospital strains of nosocomial infections in COVID-19 hospitals, which justifies the need to improve infection control measures in the context of a new coronavirus infection pandemic.

Relevance. The socio-economic significance of mumps is determined by complications after a previous infection, affecting reproductive function, what entails economic and demographic losses. An important problem today remains the fact that despite high coverage with preventive vaccinations outbreaks of mumps are recorded among children and young adults. Aim. Analyze the epidemic situation with epidemic parotitis in the world according to various literary sources and evaluate measures to control and combat this infection. Conclusions. Outbreaks of mumps have been reported among religious and ethnic groups. Outbreaks were often recorded in organized student and military groups, mainly among persons twice vaccinated. The most affected by the mumps virus were adolescents and young adults, mostly males. Several researchers have shown the possibility of using a third dose of MMR vaccine to control an outbreak, but its short-term effect does not provide conclusive evidence for rethinking two-dose mumps immunization.

Relevance Antimicrobial resistance (AMR) is a growing acute global health issue. Uncontrolled combined use of antibiotics determines changes in the microbial agents' properties, leading to a decrease of susceptibility to antimicrobial substances and increasing the probability of severe invasive bacterial infections with limited possibilities to treat them. Vaccination against pneumococcal infection as well as improvement of the health care providers awareness can be considered as part of AMR management strategies. A number of epidemiological observations have been published indicating a change in antimicrobial resistance to Streptococcus pneumoniae following the implementation of the national infant immunization program against pneumococcal infection. Aim. To analyze the literature data on the pneumococcal vaccination contribution to the reduction of the number of pneumococcal diseases and the need for antibacterial therapy and to assess the burden of invasive pneumococcal diseases globally and in the Republic of Belarus (RB) and to identify gaps in the awareness of practicing physicians on pneumococcal infection immunoprophylaxis, its' effectiveness and impact on AMR. Conclusions. WHO considers and promote vaccination as an AMR containment measure. There are a lot of publications with the examples of countries with pneumococcal infection pediatric national immunization programs (NIP) and epidemiological data on changes in the S.pneumoniae sensitivity to antibacterial drugs after the start of the NIP. During the period of the mass PCV immunization and the subsequent drift of strains the sensitivity to antimicrobials may return. In Israel 88% and 93% reduction of otitis media cases caused by resistant to penicillin and macrolides vaccine types of S.pneumoniae after the phased introduction of PCV7 and PCV13 to the infant NIP, comparing to the period before vaccination introduction. A decrease in the frequency of bacteremia in combination with a sharp decrease in the proportion of penicillin-resistant pneumococcal isolates (from 50.9% to 5.3%) is also described. In France the proportion of S.pneumoniae strains with reduced susceptibility or resistance to penicillin declined from 47.1% to 39% after the start of PCV13 NIP; researchers also noted a decrease in antibiotic-resistant isolates of S.pneumoniae in children with otitis media: by 26, 31, 55, 29 and 57%, respectively, to penicillin, amoxicillin, cefotaxime, erythromycin and co-trimoxazole to in 2011. A study in Germany revealed a decrease in macrolide-resistant IPD strains after the start of PCV13 use of (in children 8.2%; in adults 8.8%) compared with the period after the introduction of PCV7 (17.3% and 13.0%) and especially in the cohort of children compared with the period before the use of PCV7 (24.8% and 13.3%). In Scotland, there was a decrease in the number of penicillin-resistant strains isolated from the blood of patients with IPD after the introduction of PCV13 into the NIP. The publication of the results of three parallel studies in Finland evaluated the effectiveness of PCV10 in reducing the number of IPD caused by vaccine-specific serotypes of PCV10 by 93%, 98% and 100%, respectively. At the same time, the effectiveness against «related» PCV10 serotypes was equal to 46%, 51% and 78%, respectively, and the estimated effectiveness against unrelated PCV10 serotypes was negative. Composition and resistance profile of the lower respiratory tract microflora isolated from sputum pneumococcal strains in children in 2016–2018, demonstrated up to 72.4% resistance to macrolides, 31.3% resistance to cefotaxime and 8.3% – to ceftriaxone. Spn serotypes structure in under 5 years of age children with meningitis was characterized by relatively high uniformity. Majority (92%) of multiresistant meningeal strains are covered by current PCVs. An anonymous questionnaire showed pediatricians' insufficient awareness about current approaches to pneumococcal infection prevention, underestimation of IPD risks and complications, and the impact of vaccination on reducing AMR. Additional education is required to increase the level of knowledge and understanding of the PCVs role in AMR reduction. PCV NIP introduction will provide additional opportunities to reduce AMR in the Republic of Belarus.

Relevance. The sudden epidemiological complications that have emerged in the current century have highlighted the serious difficulties on the part of medical services and States in general in responding to epidemiological emergencies of international significance, which required a comprehensive study of the scale of the problem of the negative socio-economic consequences of epidemics for the modern state. The aim of the work was to study the factors that determine the current configuration of medical and social risks in the pre-epidemic period and form the socio-economic significance of epidemics and pandemics in a developed postindustrial society. The results are based on the monitoring, analysis and aggregation of information from specialized national and international industry publications and online resources (medical, socio-economic), as well as materials from peer-reviewed periodicals, on the practical development of author's approaches and assessments of the functioning of the anti-epidemic preparedness system at the international and national levels. Modern factors that aggravate the negative consequences of the pandemic for demography and the state economy in the absence of immunoprophylaxis and specific therapy are identified. Conclusion. The socio-economic significance of epidemiological events in the modern post-industrial society is significantly higher than the predicted level, based on the calculations of the cost of a clinical case of an infectious disease used in the previous century, namely: without including the costs of sanitary and anti-epidemic measures in the foci of the disease, for the deployment of a hospital base; for ensuring a strict anti-epidemic regime of work in medical institutions, for the rehabilitation and restoration of health of persons who have suffered an infectious disease; for the organization of preventive measures in non-medical organizations and enterprises (including information and explanatory work among the population); for the organization of medical care for persons with somatic pathology.