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Objective of the research - to specify respiratory tract bacterial microflora in patients suffering from community-acquired pneumonia (CAP) during initial and repeat examination. To determine local factors affecting microflora in the cohort examined. Materials and methods. Surveillance subject - 241 patients with CAP differed by their status and age who stayed in two healthcare facilities of the Khabarovsk city. Examination of respiratory smears was performed. Results. Indices of Gram-negative enterobacteria (30.8% [22.6-39.7%]) and Gram-negative nonfermentable bacteria (14.5% [8.6-21.7%]), isolated from patients hospitalized in healthcare institution No. 1 and mostly comprised of the elderly (aged over 61 years - 82.0%;74.3-88.6%) with more severe disease state including patients at the ICU, were higher compared to data obtained from healthcare institution No. 2 (19.8% (13.4-27.0);6.1% (2.7-10.8) respectively). Prevalent pathogen was Klebsiella pneumoniae - 13.6% (7.8-20.6) and 10.7% (6.0-16.5). Identification of Acinetobacter baumannii complex 6.4% (2.6-11.7) and 3.1% (0.8-6.7) - should be also noted. A high percentage of drug-resistant bacterial variants was observed and for Klebsiella pneumoniae totaled 66.7% (41.8-87.4) and 57.1% (32.2-80.2) at the healthcare institutions No. 1 and No. 2, respectively. A. baumannii complex drug resistant variants were found in 85.7% (52.7-99.97) at healthcare institution No. 1. All isolates of A. baumannii complex at the healthcare institution No. 2 were drug resistant. High prevalence of Candida spp. was revealed in both healthcare institutions reaching 54.5% (45.2-63.7) and 58.0% (49.5-66.3), respectively, with minimal detection rate of classic pathogens such as S. pneumoniae - 5.4% (2.0-10.4) and 5.3% (2.1-9.8) and H. influenzae - 3.6% (0.9-7.9) and 3.8% (1.2-7.7), respectively. Repeat examination of 122 patients conducted 7-10 days later showed diverse changes in microflora spectrum regardless of the healthcare institution that was manifested as loss or emergence of drug-resistant variants as well as simultaneous presence of different variants of the same pathogen. Conclusion. The results obtained evidence about complexity and variety of mechanisms underlying microorganism community formation during the course of infectious process in patients. Local factors influencing microflora characteristics of patients at the two healthcare institutions were revealed.
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Microbiological monitoring after infectious diseases in the system of epidemiological surveillance implies simultaneous pathogen identification both among patients and in hospital environment. Our aim is to assess potential hospital environmental hazard for the two in-patient infectious disease hospitals of the Khabarovsk city by using bacteriological and epidemiological analysis during new coronavirus disease pandemic. Materials and methods. Bacteriological assessment of nasopharyngeal microflora in 241 patients suffering from community-acquired pneumonia that were hospitalized in the two prevention and treatment facilities of the Khabarovsk city was performed. Sanitary-bacteriological control of hospital environment (428 hospital environment samples and 91 air samples) was carried out in parallel. Bacteriological assessment was performed with classical methods. Identification of isolated bacteriological pathogens and evaluation of drug-resistant strains were carried out by utilizing bacteriological analyzer Vitek 2 Compact. Results. Nine different pathogens (Pseudomonas aeruginosa, Pseudomonas stutzeri, Acinetobacter baumannii, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter cloacae, Pantoea, Enterococcus faecium, Staphylococcus haemolyticus) were isolated in 20 out of 428 samples - 4.7% [2.7-6.7]. Half of isolated agents - 2.3% [0.9-3.8] - were represented by drug-resistant isolates (10 out of 20 isolates) including 5 carbapenem-resistant isolates (Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae) and 5 isolates with multiple drug resistance (Enterobacter cloacae, Pantoea, Enterococcus faecium, Staphylococcus haemolyticus). Air samples contained pathogenic biological agents found in 6 out of 91 samples - 6.6% [1.5-11.7], and half of them - 3.3% [0.6-7.9] - were identified as drug-resistant variants, including S. aureus. S. haemolyticus. One of the surveyed hospitals was recognized as more hazardous due to microflora isolated from intensive care unit (A. baumannii and P. aeruginosa were resistant to 3rd- 4th generation cephalosporins and carbapenems). Conclusion. Revealed circulation of wide range of microorganisms isolated from environment of two in-patient hospitals indicates high risk of healthcare-associated infections formation. Intensive care units can serve as a reservoir of healthcare-associated infections due to high percentage of patients with severe disease cases ("main reservoir" of drug-resistant strains).
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Background. The ongoing pandemic of the novel coronavirus infection (COVID-19) draws attention to the significance of molecular and genetic monitoring of the SARS-CoV-2 spread among the population of the Russian Federation. The aim of the study was to analyze the dynamics of circulation of SARS-CoV-2 genetic variants in Russia. Materials and methods. The analysis of the circulation dynamics for SARS-CoV-2 genetic variants in Russia was carried out, covering the period from 28/12/2020 to 26/6/2022. The analysis included the data from Rospotrebnadzor Report No. 970 "Information about Infectious Diseases in Individuals with Suspected Novel Coronavirus Infection" and the Virus Genome Aggregator of Russia (VGARus). The presence of SARS-CoV-2 RNA was confirmed by the real-time reverse transcription polymerase chain reaction. The primer panels developed at the Central Research Institute of Epidemiology were used for amplification of genomic fragments and the subsequent sequencing. Results and discussion. Using the Russian VGARus platform developed by the Central Research Institute of Epidemiology, we received the data on mutational variability of SARS-CoV-2. By monitoring the circulation of SARS-CoV-2 genetic variants in Russia from 28/12/2020 to 26/6/2022, we found that Delta and Omicron genetic variants prevailed at different stages of the epidemic. Conclusion. The data of molecular and genetic studies are an essential component of epidemiological surveillance, being critically important for making executive decisions aimed at prevention of further spread of SARS-CoV-2 and laying the groundwork for creating new vaccines. © 2022, Central Research Institute for Epidemiology. All rights reserved.
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Background. The ongoing pandemic of a new coronavirus infection (COVID-19) determines the relevance of the analysis of epidemiological patterns of SARS-CoV-2 spread among the population of the Russian Federation. Aim — study of the manifestations of the epidemic process of COVID-19 in the Russian Federation in 2020–2022. Materials and methods. A retrospective epidemiological analysis of the incidence of COVID-19 in the Russian Federation was carried out from 03/30/2020 to 04/24/2022. The data from the Rospotrebnadzor report No. 970 “Information on cases of infectious diseases in persons with suspected new coronavirus infection”, information portal Stopcoronavirus.rf, etc. were used. The presence of SARS-CoV-2 RNA was confirmed by real-time RT-PCR. Results and discussion. The analysis of the manifestations of the epidemic process of COVID-19 in the Russian Federation in 2020–2022 showed the presence of two stages which differed depending on the influence of the biological factor and the ongoing anti-epidemic measures. There was a pronounced trend in the development of the epidemic process, starting from megacities (Moscow, Moscow region and St. Petersburg), which are major transport hubs and centers of migration activity of the population, to the regions of the Russian Federation. The SARS-CoV-2 pathogenicity has been shown to decrease with each subsequent cycle of the rise in the incidence of COVID-19 against the background of the increased contagiousness of the virus. Conclusion. As a result of the study, risk areas (megacities) and risk groups were identified. © 2022, Central Research Institute for Epidemiology. All rights reserved.
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Objective: To study the seroprevalence of SARS-CoV-2 antibodies (AB) in children in the 2nd year of the COVID-19 pandemic in Russia. Materials and methods: Prospective cohort study. The seroprevalence research was conducted among 3670 children aged 1 to 17 y/o from 26 modelling regions of Russia (that have been participating earlier in the five stages of seromonitoring during 2020-2021). The serological testing was carried out in December, 2021. The work was carried out according to a unified methodology set by the Russian Federal Service for Supervision of Consumer Rights Protection and Human Well-Being with the Pasteur Institute of Epidemiology and Microbiology (Saint Petersburg, Russia). The plasma was obtained from 3 ml of venous blood, in which the level of AB to nucleocapsid (NC), and the SARS-CoV-2 receptor-binding domain (RBD) was determined by immunoferment method using reagents for qualitative and quantitative analysis. Results: The analysis of AB seroprevalence to NC and RBD showed the statistically significant increase in the share of seropositivity to RBD in children of all modelling regions (p<0.05). The most seropositive volunteers contained low levels of AB: 31.3-125.6 BAU/ml NC and 22.6-220 BAU/ml RBD. An increase in the level of AB to NC and RBD was accompanied by a decrease in the percentage of seropositive patients. Evaluating the contribution of children to the level of humoral immunity, convalescents (had been ill shortly before the examination), the «anamnesis» (had been ill at previous stages of seromonitoring) and asymptomatic (had been asymptomatically ill) groups were distinguished. The maximum contribution was made by children with asymptomatic cases of COVID-19 in anamnesis: In 82.3% (95% CI 81.1-83.6), of which 76.9% (95% CI 75.5-78.3) AB detected to RBD. The contribution of children of two other groups to the overall level of humoral immunity was 33 times less. Conclusion: Statistically significant predominance of AB to RBD above AB to NC and their main contribution to the level of humoral immunity to SARS-CоV-2 (p<0.001).
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Microbiological monitoring after infectious diseases in the system of epidemiological surveillance implies simultaneous pathogen identification both among patients and in hospital environment. Our aim is to assess potential hospital environmental hazard for the two in-patient infectious disease hospitals of the Khabarovsk city by using bacteriological and epidemiological analysis during new coronavirus disease pandemic. Materials and methods. Bacteriological assessment of nasopharyngeal microflora in 241 patients suffering from community-acquired pneumonia that were hospitalized in the two prevention and treatment facilities of the Khabarovsk city was performed. Sanitary-bacteriological control of hospital environment (428 hospital environment samples and 91 air samples) was carried out in parallel. Bacteriological assessment was performed with classical methods. Identification of isolated bacteriological pathogens and evaluation of drug-resistant strains were carried out by utilizing bacteriological analyzer Vitek 2 Compact. Results. Nine different pathogens (Pseudomonas aeruginosa, Pseudomonas stutzeri, Acinetobacter baumannii, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter cloacae, Pantoea, Enterococcus faecium, Staphylococcus haemolyticus) were isolated in 20 out of 428 samples — 4.7% [2.7–6.7]. Half of isolated agents — 2.3% [0.9–3.8] — were represented by drug-resistant isolates (10 out of 20 isolates) including 5 carbapenem-resistant isolates (Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae) and 5 isolates with multiple drug resistance (Enterobacter cloacae, Pantoea, Enterococcus faecium, Staphylococcus haemolyticus). Air samples contained pathogenic biological agents found in 6 out of 91 samples — 6.6% [1.5–11.7], and half of them — 3.3% [0.6–7.9] — were identified as drug-resistant variants, including S. aureus и S. haemolyticus. One of the surveyed hospitals was recognized as more hazardous due to microflora isolated from intensive care unit (A. baumannii and P. aeruginosa were resistant to 3rd–4th generation cephalosporins and carbapenems). Conclusion. Revealed circulation of wide range of microorganisms isolated from environment of two in-patient hospitals indicates high risk of healthcare-associated infections formation. Intensive care units can serve as a reservoir of healthcare-associated infections due to high percentage of patients with severe disease cases (“main reservoir” of drug-resistant strains).
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Objective. Detection of additional factors favoring progression of COVID-19 and developing lethal outcomes in hospitalized patients. Materials and methods. Analysis of 98 medical records of lethal cases of patients that underwent hospitalization with diagnosis of COVID-19 associated pneumonia of two in-patient facilities of the Amur oblast and Khabarovsk krai was performed. Two groups were formed: first included medical records of patients hospitalized in severe condition (n = 52) and second group included patients with state of moderate severity (n = 46). Length of hospitalization stay, time from admission to the medical facility to progression of the disease, time from hospitalization to death and bacterial pathogens species composition isolated from lungs tissue autopsy material were analyzed. Statistical assessment of obtained data was performed with StatSoft Statistica 12.0. Results. Majority of patients of 1st and 2nd groups (66.7 ± 6.80% and 69.6 ± 6.78%) were hospitalized on fourth day of the COVID-19 clinical manifestations onset or later. Two thirds of patients hospitalized in severe condition progressed to critical health status on 1st–3rd day of hospitalization. Majority of second group patients (65.2 ± 7.02%) deteriorated from moderate severity to severe health condition on 4th–14th day of hospital stay. Bacteriological assessment analysis of autopsy material revealed that material obtained from first group showed more frequent absence of bacterial flora growth compared with second group both in the Amur oblast (44.4 ± 9.74% и 29.4 ± 11.39%) and in the Khabarovsk krai (в 40.0 ± 10.0% and 27.6 ± 8.45% of cases). Klebsiella pneumoniae (57.7 ± 5.86%) and Candida spp. (18.3 ± 4.59%) were revealed more frequently in the structure of diagnosed pathogens. Substantial proportion of pathogens (81.7 ± 4.59%) were isolated in autopsy material of patients which hospital stay was 4 days and longer. Prolonged hospital stay was associated with more frequent detection of K. pneumoniae and Candida spp. in patients that suffered from COVID-19 pneumonia and eventually died from the disease. With duration of hospitalization of 4 days and longer Acinetobacter baumannii – an extremely virulent pathogen with natural drug resistance was isolated from autopsy material. Conclusion. Factors influencing unfavorable outcomes of COVID-19 include signs of secondary bacterial infection as well as detection of aggressive drug-resistant bacterial microflora that most likely had nosocomial origin due to prolonged hospitalization. © 2021, Dynasty Publishing House. All rights reserved.
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Objective – integral analysis of effectiveness of anti-epidemic measures applied towards employees of the Amur gas processing plant assigned for rotational work under conditions of COVID-19 pandemic. Materials and methods. Sero-epidemiological study included a questionnaire survey of 1461 workers who arrived through the “clean corridor” in the Amur Region, followed by sampling of biological material (blood and respiratory smears). Testing of blood sera for the presence of antibodies to SARS-CoV-2 of two classes (IgM and IgG) was carried out applying enzyme immunoassay. Using PCR, respiratory smears were examined for the presence of the agent RNA in them. Statistical processing of the results obtained was carried out using conventional methods. Results and discussion. The presence of antibodies of the IgG class was revealed in (4.7±0.55) % of cases. In a small cohort (1.7±0.34 %) of practically healthy individuals, asymptomatic infection was detected, confirmed either by a positive PCR result (0.76±0.23 %), or by the detection of IgM antibodies (1.0±0.08 %). On the basis of the study carried out by the Federal Service for Surveillance in the Sphere of Consumer Rights Protection and Human Welfare on August 01, 2020, “Temporary recommendations on the procedure for admitting to work on a rotational basis under the risk of COVID-19 spread in the Amur Region” were approved. These recommendations set out the algorithm for observation of incoming workers and the order for triage of shift workers after testing by ELISA and PCR. The results of the study demonstrate the effectiveness of anti-epidemic measures related to ensuring the procedure for admission to work on a rotational basis under the risks of the spread of COVID-19. © 2021 Russian Research Anti-Plague Institute. All rights reserved.
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The aim: to study the structure and dynamics of population immunity to SARSCoV-2 of the population of the Southern Regions of the Far East (SRFE): Khabarovsk, Primorsky Krai and Amur Region during the COVID-19 epidemic in 2020. Materials and methods. The work was carried out according to the program for assessing population immunity to SARS -CoV-2 of the population of the Russian Federation according to the methodology developed by the Rospotrebnadzor with the participation of the St. Petersburg Pasteur Institute. The study was approved by the ethical committee of the St. Petersburg Pasteur Institute. The selection of participants was carried out by a questionnaire method using cloud technologies. The volunteers were randomized by age by stratification into 7 age groups: 1–17, 18–29, 30–39, 40–49, 50–59, 60–69, 70+ years old. Territorial randomization consisted in limiting the engaging of volunteers – no more than 30 people from one enterprise. After the initialcross-sectionalstudy, a 3-stage seromonitoring was carried out, in which the same volunteers participated. Antibodies to the SARS-CoV-2 nucleocapsid were determined in peripheral blood serum by the enzyme immunoassay using an appropriate set of reagents produced by the State Scientific Center for Medical and Biological Sciences of the Rospotrebnadzor (Obolensk). Statistical analysis was performed using the Excel package. The confidence interval for the proportion was calculated using the A. Wald, J. Wolfowitz method with A. Agresti, B.A. Coull’s correction. The statistical significance of the differences was calculated online using a specialized calculator. The statistical significance of the differences was assessed with a probability of p < 0.05, unless otherwise indicated. Results. In a comparative analysis, the highest morbidity was observed in the Khabarovsk Territory, the lowest – in the Primorsky Territory. The level of seroprevalence among the population of the region was 19.6 % (95 % CI: 18.2–21.1) in the Khabarovsk Territory, 19.6 % (95 % CI: 18.1–21.2) in the Primorsky Territory19,6 % and 45,5 % (95 % CI: 43.7–47.3) in the Amur region. The highest seroprevalence was noted among 1–17 years old children, mainly due to the subgroup of 14–17-years-olds. The smallest proportion of seropositive was found among 40–49-year-olds in the Khabarovsk Territory (14.7 %, 95 % CI: 11.2–18.6), 18–28-year-olds in the Primorsky Territory (13.3 %, 95 % CI: 10.0–17.1) and 30–39-year-olds in the Amur Region (36.3 %, 95% CI: 31.7–41.6). No statistically significant dependence of seroprevalence on territorial and occupational factors has been established, with the exception of an increase in the proportion of seropositive medical workers in Primorsky Territory. In the process of 3-stage seromonitoring, a regular increase in the proportion of seropositive people was revealed in all SRFE. The resulting tendency is correctly describedby a second-order polynomial. Arelationship was revealed between the number of convalescents and persons in contact with them, which made it possible to calculate the base reproductive number (R0) in the range from 1.4 (Primorsky Territory) to 2.4 (Amur Region). Analysis of seroprevalent volunteers showed that the number of asymptomatic individuals varied from 94.1 % (95 % CI: 92.8–95.3) to 98.3 % (95 % CI: 98.8–99.2). This indicates that most of the volunteers had COVID-19 asymptomatically. Conclusions. A comparative study showed the prevalence of seroprevalence in the Amur Region compared with the Khabarovsk and Primorsky Territories. The relationship between the number of convalescents and persons in contact with them was noted. The value of the base R0 is calculated. It has been shown that more than 90 % of seropositive individuals in the COVID-10 SRFE were asymptomatic. © 2021 Scientific Centre for Family Health and Human Reproduction Problems. All rights reserved.
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The novel coronavirus (SARS-CoV-2) pandemic, dubbed COVID-19, has become one of the most serious challenges for human populations in the vast majority of countries worldwide. Rapid spreading and increased mortality related to it required new approaches to manage epidemic processes on a global scale. One of such approaches was based on analyzing SARS-CoV-2 seroprevalence associated with COVID-19. Our aim was to summarize the results on assessing seroprevalence to the SARS-CoV-2 nucleocapsid antigen (Nc) in residents from 26 regions of the Russian Federation, carried out during the first wave of the COVID-19 epidemic. Materials and methods. Seroprevalence distribution was examined in 26 model regions of the Russian Federation according to the unified method developed by the Rospotrebnadzor with the participation of the Federal State Institution Saint Petersburg Pasteur Research Institute of Epidemiology and Microbiology. Such approach implied formation of a group of volunteer subjects in model geographic region who were tested by ELISA for anti-Nc serum antibody level in peripheral blood. Analyzed primary data obtained in separate regions were either accepted for publication or released. Results. The current paper finalizes the data obtained in all 26 regions of the Russian Federation. The total SARS-CoV-2 seroprevalence was 19.5 (10.0-25.6)% with the maximum and minimum value found in the Kaliningrad Region and the Republic of Crimea, respectively (50.2% vs. 4.3%). A pattern of age-related seroprevalence distribution indicates insignificant predominance of seroprevalence among subjects of 1-17 years old: 22.1 (13.1-31.8)%. Among COVID-19 convalescents positive for SARS-CoV Nc antibodies it reached 60.0 (40.0-73.3)%. The number of contact persons comprised 6285 subjects or 8.5% of total volunteer cohort, with the level of seroprevalence reaching up to 25.3 (17.95-35.8)%. A direct correlation was revealed between levels of seroprevalence in convalescent and contact volunteers. In addition, the reproductive number for SARS-CoV was calculated comprising 5.8 (4.3-8.5) suggesting that one convalescent subject can infect at least 4 healthy individuals. A high level of asymptomatic forms of COVID-19 among seropositive subjects was confirmed empirically comprising up to 93.6 (87.1-94.9)%. Conclusion. A single cross-sectional study performed during 2020 June-August timeframe allowed to assess pattern of sex- and age-related COVID-19 seroprevalence for general population in 26 Russian Federation regions. The data obtained may serve as a basis for the longitudinal cohort investigation with serial subject sampling. The timing and duration of study will be determined by dynamics of ongoing COVID-19 epidemic.
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Relevance. Pandemic of the new coronavirus infection has become a challenging issue for world healthcare system. Control of the epidemic process is one of the main priorities in combat against new coronavirus disease Aim. The research highlights the issue of asymptomatic carriers of the new coronavirus disease. Conclusions. It was revealed that patients wth asymptomatic form of COVID-19 have a less lasting immunity response compared wth those that have had clinically active forms of the infection. In order to determine pathogenetic process and fully understand formation of the immune response, t is necessary to study both humoral and cellular immune responses in patients diagnosed wth COVID-19. In order to select most optimal anti-epidemic measures to contain the further spread of the disease, including asymptomatic carriage, it is necessary to establish SARS-CoV-2 reproduction index and determine minimal infective dose of SARS-CoV-2. Актуальность. Пандемия новой коронавирусной инфекции является серьезным испытанием для мировой системы здравоохранения, а контроль за развитием эпидемического процесса одна из главных задач в борьбе с C0VID-19. Цель. По данным зарубежной литературы оценить роль бессимптомных носителей C0VID-19 в эпидемическом процессе новой коронавирусной инфекции. Выводы. Показано менее стойкое формирование иммунного ответа у лиц с бессимптомной формой заболевания по сравнению клиническими формами инфекции C0VID-19. Для выяснения аспектов патогенетического процесса и установления реальной стойкости иммунного ответа помимо исследования гуморального иммунного ответа целесообразно изучение клеточного звена иммунитета, в особенности клеток памяти у лиц, перенесших C0VID-19. С целью подбора наиболее оптимальных противоэпидемических мер для сдерживания дальнейшего распространения заболевания, в том числе бессимптомного носительства необходимо установление индекса репродукции и определение минимальной инфицирующей дозы SARS-CoV-2
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Objective: to study the bacterial microflora in the sputum of patients with pneumonia caused by SARSCoV-2 or other pathogens. Materials and methods. The bacterial microflora of sputum of 173 patients with pneumonia admitted to hospitals in Khabarovsk and the Khabarovsk Territory in May – June 2020 was examined. Detection of RNA of the SARS-CoV-2 virus was carried out by PCR with the Vector-PCRRV-2019-nCoV-RG test system (manufactured by the State Scientific Center of VB “Vector”, Koltsovo). Determination of the DNA of mycoplasmosis agents and chlamydia was carried out with the test system “AmpliSens® Mycoplasma pneumoniae/Chlamydophila pneumonia” (manufactured by CRIE). Statistical data processing was performed using the Excel program. Results and discussion. Both groups of patients (Covid-19+ and Covid-19–) had high levels of bacterial flora isolation (81.4 and 74.7 %) including common pathogens for community-acquired pneumonia as well as notable detection frequency of Candida spp. and microbial associations. The group of Covid-19+ patients demonstrated a wider range of detected pathogens, was positive for poly-resistant gram-negative Enterobacteriaceae, non-fermenting gram-negative poly-resistant bacteria, with more expressed manifestation of microbial associations. In the group of Covid-19– participants drug-resistant microflora was presented only by MRSA and MRSE staphylococci. © 2020 Russian Research Anti-Plague Institute. All rights reserved.