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Purpose. The study of epidemiological and clinical and laboratory features and outcomes of multisystem inflammatory syndrome in children who were hospitalized against the backdrop of the current COVID-19 pandemic. Materials and methods. In 19 months (May 2020 - December 2021) 63 patients with a diagnosis of "Multisystem inflammatory syndrome in children" (MIS-C) associated with COVID-19 were observed in Anesthesiology and Intensive Care departments of the Healthcare Institution "City Children's Infectious Clinical Hospital" in Minsk, Republic of Belarus. MIS-C was diagnosed according to CDC/WHO criteria, 2020. All calculations were carried using the R Statistical Package, version 4.1. The results of the analysis were considered statistically significant with p<0.05. Results. Focusing on the periods of circulation of dominant coronaviruses, we generated 3 groups of patients. The 1st group included 40 patients (63.5%) received treatment from 05.25.2020 to 02.21.2021 ("wuhan" strains);the 2nd group comprised 9 children (14.3%) from 02.23.2021 to 06.13.2021 ("alpha");and the 3rd group consists of 14 children (22.2%) from 07.01.2021 to 11.19.2021 ("delta"). 47 (74.6%) patients had complete and incomplete Kawasaki Disease phenotype of MIS-C;nonspecific phenotype was observed in 16 (25.4%) children. The mean age didn`t differ in study groups. It was 7+/-2.5;9.4+/-4.2;7.9+/-5 years respectively. All children presented hyperthermic syndrome with febrile fever 3-4 times a day of an average duration of 3.2 (1-15) days. Clinically, the course of MIS-C in children was not dependent on the circulating strain of the virus, and gastrointestinal dysfunction was observed with equal frequency in all three groups (73%, 78% and 57%, respectively). The only statistically significant increase in number of children with cheilitis was observed in the 2 group - 8 (89%) and the 3 group - 13 (93%), p=0.002. Neurological disorders such as headache, hyperesthesia, hallucinations, photophobia were more frequently observed in the 1st group of children - 19 (48%) cases, and less frequently in the 2nd and 3rd group (in 11% and 14% of cases), p=0.022. Pathological blood flow regurgitation was the most common disorder (68-71%). Several biochemical markers of inflammation levels, such as C-reactive protein (CRP) and procalcitonin (PCT) were high. CRP levels were 162 mg/l (130;245);130 mg/l (90;160);130 mg/l (106;149) in 1-2-3 study groups, respectively. In children of the 1st group CRP level was significantly higher, p=0.052. PCT level was higher in patients of the 3rd group (4.2 ng/ml (2.4;8.8);3.9 ng/ml (3.2;11.9);8.7 ng/ml (3.4;14.1), respectively, p=0.625). Conclusion. The study revealed no appreciable association between clinical or laboratory features of MIS-C and the dominant circulating strain of SARS-CoV-2 within given time periods. During "alpha" and "delta" strains circulation, only a decrease in the number of patients with neurological disorders and an increase in the frequency of cheilitis were of significant differences, p=0.002. The remaining indicators of organ dysfunction were similar in all three groups of children. There was 1 (1.6%) fatal outcome in our study.Copyright © 2022, Professionalnye Izdaniya. All rights reserved.
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Purpose. The study of epidemiological and clinical and laboratory features and outcomes of multisystem inflammatory syndrome in children who were hospitalized against the backdrop of the current COVID-19 pandemic. Materials and methods. In 19 months (May 2020 - December 2021) 63 patients with a diagnosis of "Multisystem inflammatory syndrome in children" (MIS-C) associated with COVID-19 were observed in Anesthesiology and Intensive Care departments of the Healthcare Institution "City Children's Infectious Clinical Hospital" in Minsk, Republic of Belarus. MIS-C was diagnosed according to CDC/WHO criteria, 2020. All calculations were carried using the R Statistical Package, version 4.1. The results of the analysis were considered statistically significant with p<0.05. Results. Focusing on the periods of circulation of dominant coronaviruses, we generated 3 groups of patients. The 1st group included 40 patients (63.5%) received treatment from 05.25.2020 to 02.21.2021 ("wuhan" strains);the 2nd group comprised 9 children (14.3%) from 02.23.2021 to 06.13.2021 ("alpha");and the 3rd group consists of 14 children (22.2%) from 07.01.2021 to 11.19.2021 ("delta"). 47 (74.6%) patients had complete and incomplete Kawasaki Disease phenotype of MIS-C;nonspecific phenotype was observed in 16 (25.4%) children. The mean age didn`t differ in study groups. It was 7+/-2.5;9.4+/-4.2;7.9+/-5 years respectively. All children presented hyperthermic syndrome with febrile fever 3-4 times a day of an average duration of 3.2 (1-15) days. Clinically, the course of MIS-C in children was not dependent on the circulating strain of the virus, and gastrointestinal dysfunction was observed with equal frequency in all three groups (73%, 78% and 57%, respectively). The only statistically significant increase in number of children with cheilitis was observed in the 2 group - 8 (89%) and the 3 group - 13 (93%), p=0.002. Neurological disorders such as headache, hyperesthesia, hallucinations, photophobia were more frequently observed in the 1st group of children - 19 (48%) cases, and less frequently in the 2nd and 3rd group (in 11% and 14% of cases), p=0.022. Pathological blood flow regurgitation was the most common disorder (68-71%). Several biochemical markers of inflammation levels, such as C-reactive protein (CRP) and procalcitonin (PCT) were high. CRP levels were 162 mg/l (130;245);130 mg/l (90;160);130 mg/l (106;149) in 1-2-3 study groups, respectively. In children of the 1st group CRP level was significantly higher, p=0.052. PCT level was higher in patients of the 3rd group (4.2 ng/ml (2.4;8.8);3.9 ng/ml (3.2;11.9);8.7 ng/ml (3.4;14.1), respectively, p=0.625). Conclusion. The study revealed no appreciable association between clinical or laboratory features of MIS-C and the dominant circulating strain of SARS-CoV-2 within given time periods. During "alpha" and "delta" strains circulation, only a decrease in the number of patients with neurological disorders and an increase in the frequency of cheilitis were of significant differences, p=0.002. The remaining indicators of organ dysfunction were similar in all three groups of children. There was 1 (1.6%) fatal outcome in our study.Copyright © 2022, Professionalnye Izdaniya. All rights reserved.
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In April 2020, pediatricians in England reported the cases of severe disease in high schools for children and adolescents, characterized by fever, hypotension, severe abdominal pain, and cardiac dysfunction, with confirmation of positive result for SARS-CoV-2 infection. As the pandemic is spreading around the world, different pediatricians describe an unusual systemic inflammatory response associated with the SARS-CoV-2 virus after the beginning of acute viral infection up to several weeks. It is a review of current data on the impact and association of coronavirus infection-2019 (COVID-19) with the development of severe disease and multisystem inflammatory syndrome, which involves several organs and not only heart damage. It also includes definitions of multisystem inflammatory syndrome cases presented by the Center for disease control (USA) and WHO. The results of foreign researchers on diagnostics, differential diagnosis, and treatment in children are cited.Copyright © 2020, Professionalnye Izdaniya. All rights reserved.
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Purpose. The study of epidemiological and clinical and laboratory features and outcomes of multisystem inflammatory syndrome in children who were hospitalized against the backdrop of the current COVID-19 pandemic. Materials and methods. In 19 months (May 2020 – December 2021) 63 patients with a diagnosis of "Multisystem inflammatory syndrome in children" (MIS-C) associated with COVID-19 were observed in Anesthesiology and Intensive Care departments of the Healthcare Institution "City Children's Infectious Clinical Hospital" in Minsk, Republic of Belarus. MIS-C was diagnosed according to CDC/WHO criteria, 2020. All calculations were carried using the R Statistical Package, version 4.1. The results of the analysis were considered statistically significant with p<0.05. Results. Focusing on the periods of circulation of dominant coronaviruses, we generated 3 groups of patients. The 1st group included 40 patients (63.5%) received treatment from 05.25.2020 to 02.21.2021 ("wuhan" strains);the 2nd group comprised 9 children (14.3%) from 02.23.2021 to 06.13.2021 ("alpha");and the 3rd group consists of 14 children (22.2%) from 07.01.2021 to 11.19.2021 ("delta"). 47 (74.6%) patients had complete and incomplete Kawasaki Disease phenotype of MIS-C;nonspecific phenotype was observed in 16 (25.4%) children. The mean age didn`t differ in study groups. It was 7±2.5;9.4±4.2;7.9±5 years respectively. All children presented hyperthermic syndrome with febrile fever 3–4 times a day of an average duration of 3.2 (1–15) days. Clinically, the course of MIS-C in children was not dependent on the circulating strain of the virus, and gastrointestinal dysfunction was observed with equal frequency in all three groups (73%, 78% and 57%, respectively). The only statistically significant increase in number of children with cheilitis was observed in the 2 group – 8 (89%) and the 3 group – 13 (93%), p=0.002. Neurological disorders such as headache, hyperesthesia, hallucinations, photophobia were more frequently observed in the 1st group of children – 19 (48%) cases, and less frequently in the 2nd and 3rd group (in 11% and 14% of cases), p=0.022. Pathological blood flow regurgitation was the most common disorder (68–71%). Several biochemical markers of inflammation levels, such as C-reactive protein (CRP) and procalcitonin (PCT) were high. CRP levels were 162 mg/l (130;245);130 mg/l (90;160);130 mg/l (106;149) in 1–2–3 study groups, respectively. In children of the 1st group CRP level was significantly higher, p=0.052. PCT level was higher in patients of the 3rd group (4.2 ng/ml (2.4;8.8);3.9 ng/ml (3.2;11.9);8.7 ng/ml (3.4;14.1), respectively, p=0.625). Conclusion. The study revealed no appreciable association between clinical or laboratory features of MIS-C and the dominant circulating strain of SARS-CoV-2 within given time periods. During "alpha" and "delta" strains circulation, only a decrease in the number of patients with neurological disorders and an increase in the frequency of cheilitis were of significant differences, p=0.002. The remaining indicators of organ dysfunction were similar in all three groups of children. There was 1 (1.6%) fatal outcome in our study. © 2022, Professionalnye Izdaniya. All rights reserved.
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Introduction: It is known that atrial fibrillation (AF) is one of the most common arrhythmias in patients (pts) who have had a COVID-19 infection (CI).The aim of our study was to evaluate systolic and diastolic functions of the left ventricle (LV) and heart rate variability (HRV) in pts with AF depending on the past CI.Research material and methods 131 pts with paroxysmal or persistent forms of AF in sinus rhythm were studied. 93 people had a history of an average of 6.2±0.5 months ago of COVID-19 infection. They made up the 1st group of examined pts. The remaining 38 patients did not have a history of this infection. They constituted the 2nd group of the study group, which was the control group. Transthoracic echocardiography and Holter monitoring ECG were performed according to the standard technique. Results of the study: We did not find any difference in hemodynamic parameters characterizing the systolic function of LV. So, the values of the end-diastolic volume (117.0±7.6 mm and 116.0±7.2 mm), end-systolic volume (55.7±4.9 mm and 55.2±4.7 mm) and ejection fractions (55.0±2.1% and 54.4±2.0%) in the groups did not differ significantly. However, statistical significance was obtained in indicators characterizing LV diastolic function. So, significantly different flow rates in the 1st and 2nd groups of pts – E (60.8±1.63 sm/s and 94.6±2.97 sm/s, p<0.001), A (61.8±0.83 sm/s and 73.1±1.03 sm/s, p<0.001), their E/A ratios (0.98±0.02 and 1.39 + 0.03, p<0.001) and DE score (175.9±2.20 ms and 202.5±4.03 ms, p<0.001). A more significant violation of LV diastolic function after CI led to an increase in the diameter of the left atrium (LA) (4.99±0.14 cm in the 1st group compared with 4.40±0.004 sm in the 2nd group, p<0.001) and LA index (46.4±0.011 sm in the 1st group compared with 42.93±0.08 in the 2nd group, p<0.001). We also found a significant difference in such indicators of HRV between groups “1” and “2” as – SDANN (102.7±2.33 and 151.7±1.23 ms, p<0.001), SDNN (124, 3±4.06 and 181.3±4.83 ms, p<0.001), and RMSSD (100.4±4.57 and 173.2±13.51 ms, p<0.001). Conclusion: In pts with AF, after undergoing CI, the LV diastolic function begins to suffer first, which leads to an increase in the size of the LA. Pts after CI also had a change in the autonomic regulation of the heart rhythm, and as a result, an increase in the electrical instability of the atria. Funding Acknowledgement: Type of funding sources: None.
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Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): NSC M.D Strazhesko Institute of Cardiology Coronavirus infection (CI) needs to be specified in terms of the impact on the development of first-onset arrhythmia episodes and the worsening of the course of pre-existing arrhythmias and conduction disturbances. The aim of our study was to examine the features of the most common and potentially dangerous arrhythmia - atrial fibrillation (AF) in patients with COVID-19 infection (CI). Research methods in this fragment of work the estimation of clinical and anamnestic characteristics of patients (pts) and a course of a disease is resulted. Results We studied 29 pts, including 9 men and 20 women, aged 65.7 + 1.8 years, who 3.8 + 0.6 months ago underwent CI, and were admitted to our clinic with a diagnosis of atrial fibrillation ( AF): 18 pts with paroxysmal, 8 pts with persistent and three people with permanent forms of this arrhythmia. Of these, 18 (62.1%) had AF before COVID-19 (study group 1), and 11 (37.9%) pts had this arrhythmia after CI (study group 2). In pts of the 1st group after CI there was an increased duration of AF paroxysm in all 15 pts with paroxysmal and persistent forms of AF from 1.9 + 0.4 to 59.1 + 2.0 days (p (0.001). In favor of the latter is the fact that in these patients the frequency of arrhythmia paroxysms increased from 2.5 + 0.4 times a year to 53.6 + 1.9 during the same time (up to almost once a week) (p <0.001). In addition, all three pts with persistent AF had a transition from "normosystolic" form of this arrhythmia to "tachysystolic" (100%, p <0,05). Pts of the 1st group more often had coronary heart disease (77.8% vs. 72.7%, p <0.05), a history of myocardial infarction 5.6% vs. 0%, p <0.05), stroke (11.1% vs. 0%, p <0.05), diabetes mellitus (22.2% vs. 0%, p <0.05). Pts in group 1 were older than patients in group 2 (67.7 + 1.9 years versus 63.9 + 2.4 years) (p <0.001). AF in group 1 first appeared on average 6.1 + 0.6 years before the survey, which is significantly greater than the difference in human age of 3.8 +1.9 years (p <0.001) between pts of the 1st and 2nd groups. That is, AF in pts of the 2nd group of CI dishonestly accelerated its development. Finally, the 1st group of women there were 61.1%, which is more than men, which was 38.9% 1.6 times, and in the 2nd group the number of women increased significantly ( and amounted to 81.8% to 18.2% of men), and the ratio of women to men increased to 4.5 - almost three times more than in the group of pts with AF to CI (p <0.001). Conclusions Coronavirus infection significantly worsens the course of all forms of atrial fibrillation. COVID-19 increases the likelihood of newly registered atrial fibrillation in pts without significant comorbid and age-related "load". The probability of atrial fibrillation after coronavirus infection in women is higher than in men.
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Objective: It is known that arterial hypertension (AH) is the main etiological factor in the development of atrial fibrillation (AF). The aim of our study was to assess the course of AF after infection with COVID- 19 (CI) depending on the presence of hypertension. Design and method: We examined 72 patients with AF, aged 64.5 + 1.2 years, who, on average, 6.2 + 0.5 months underwent CI. 59 (81.9%) people had AH (group 'A' patients). The remaining 13 (18.1%) patients did not have hypertension (group 'B' patients). Results: When nalysing the course of AF after CI in these groups, it was found that an increase in the frequency of AF paroxysms was observed in a significantly larger number of patients in group 'A' (32 out of 59 people, 54.2%) than in patients in group 'B' (in 3 out of 13 people, 23.1%), p < 0.001, the duration of AF paroxysms also increased more significantly in a larger number of patients in group 'A' (in 29 out of 59 people, 49.2%), than in patients of group 'B' (in 4 of 13 people, 30.8%), p < 0.001, and the surrogate indicator of deterioration in the course of AF (an increase in the frequency or duration of AF paroxysms) was also higher in group 'A' (in 36 of 59 patients, 61.0%), compared with group 'B' (5 out of 13 patients), p < 0.001. Conclusions: The presence of AH significantly worsens the course of AF after CI, increasing the frequency of paroxysms of this arrhythmia and their duration.
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This study aimed to determine how coronavirus infection provoked arrhythmias. Fifteen patients with arrhythmias who had coronavirus infection (group C +) and 10 patients who had the same arrhythmias but did not pass through COVID-19 (group C-) were examined. In most cases, atrial fibrillation or atrial flutter dominated in patients of both examined groups - 86.6 % and 80 % appropriately. Age and overweight are risk factors for arrhythmia onset after coronavirus infection. The frequency of paroxysms increased by 88.9% in patients with AF who underwent coronavirus infection, p<0.005.
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Carrying out large-scale structural transformations of both the entire Russian economy and its individual actors is one of the most important tasks of the current stage of national development. The urgency of this problem has increased dramatically during the COVID-19 pandemic. The purpose of this paper is to identify the most significant factors in the pandemic that affect the economic growth of Russia's regions and reduce territorial inequality. The use of methods of comparative and economic-statistical analysis made it possible to establish that the most important independent factor in the development of a region is the structure of the economy and such a factor that ensures it as the regional structural (industrial) policy. It has been substantiated that structural modernization is the basis for pursuing a non-contradictory short- and long-term policy to reduce interterritorial inequality. A particularly negative impact of the pandemic on regions with a low level of development of the real sector and overdevelopment of the service sector has been revealed.
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Relevance. The coronavirus pandemic has lead to one of the most serious crises in the global economy. The significant disparities between Russian regions influenced the levels of morbidity and their strategies of containing the crisis. Research objective. The aim of this paper is to identify the factors of regional development which, during the pandemic and in the post-pandemic period, affected and will affect the economic stability of Russian regions. Materials and Methods. The research is based on the Rosstat data, industry reviews, materials from analytical and consulting firms, Russian and international research literature. The research methodology is based on the structuralist approach and the provisions of the new structural economics put forward by J. Lin. The methods of comparative, statistical, and structural analysis were also used. Results. The most significant factors in regional economic development are the structure of the economy and the quality of public administration at the national and regional levels. The high-tech sector in the structure of a regional economy plays a pivotal role in ensuring its stability in the times of crisis. The study shows the need for a transition to independent national value chains. It is also necessary to develop a long-term national strategy aimed at stimulating the structural transformation of regional economies. Conclusions. The study has demonstrated the importance of the two key factors in shaping the regions’ responses to the pandemic and the speed of their recovery-the structure of regional economy and the role of the government. These factors should be taken into account by the Strategy of the State Regional Industrial Policy. © Romanova, O.A., Ponomareva, A.O., 2021.
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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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Background: Children develop severe COVID-19 much less often than adults. However, a small proportion of children present with a complication, known as a multisystem inflammatory syndrome (MIS-C) sometimes associated with admission to an intensive care unit or death. Clinical presentation and consequences of MIS-C are still unclear. The aim of our study is to assess the features of MIS-C and its consequences on a child's health. Method: An observational longitudinal study of children and adolescents hospitalised from May 17 to October 26, 2020, with MIS-C to Morozovskaya Children's City Clinical Hospital, Moscow Department of Health Care, Moscow, Russia. Results: 37 children with MIS-C (meeting WHO, CDC, or RCPCH criteria) were hospitalised. The median age was 6 years (interquartile range 3.3-9.9 years), and 22 patients (59.5%) were male. The most common symptoms on admission were fever (97.3%), fatigue (86.5%), scleritis (85%), oral mucosal inflammation (83.8%), rash (70.3%), tachycardia (51.4%), nausea (51.4%), bilateral conjunctivitis (43.2%), cervical lymphadenopathy (43.2%). The most common laboratory abnormalities detected during hospitalization were elevated CRP (100%), ferritin (100%), D-dimer (89.19%), CRP (86.49%), platelets (85.49%), hypoalbuminemia (100%) and anemia (95.59%). EchoCG abnormalities were present in 6 (16.2%) children with evidence of myocardial dysfunction, 5 (13.5%)-pericarditis, and 3 (8.1%) with a coronary anomaly. The median time from discharge to the first follow-up was 15 days (interquartile range, 14-18 days) to the second follow-up was 47 days (interquartile range, 41-52 days). At the first follow-up, 7/33 (21.21%) children had at least 1 symptom, of whom 5 (15.15%) reported fatigue. At the second follow-up, only 1 child reported a symptom (rash). The normalisation of laboratory values and EchoCG findings was noted in all the children. Conclusion: In spite of the MIS-C severity, the tendency to fast regression of symptoms and laboratory and instrumental indexes is traced, which suggests recovery of children and adolescents from MIS-C without long-term consequences. Further long-term follow-up of patients with MIS-C is necessary since data on long-term health outcomes are limited.
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Introduction. SARS-CoV-2 can be transmitted by infected people without or with mild symptoms of acute respiratory infection (ARI). Monitoring based on nucleic acid amplification techniques is used to measure the prevalence of ARI pathogens and to assess the effectiveness of preventive measures. The aim is to measure the prevalence of pathogens causing ARIs of viral etiology, influenza, and COVID-19 among individuals without ARI symptoms throughout age groups, to trace changes in the epidemic situation by weekly monitoring pathogens during the inter-epidemic period and at the beginning of a typical ARI epidemic season, to assess the effectiveness of medical masks for prevention of the above infections. Materials and methods. A total of 14,119 people (including 4,582 children) without ARI symptoms went through examination, including questionnaire surveys, in 26 regions of Russia from August to October 2020. Nasopharyngeal and oropharyngeal swabs were tested by using AmpliSens ARVI-screen-FL, AmpliSens Influenza virus A/B-FL, and AmpliSens Cov-Bat-FL reagent kits (The Central Research Institute of Epidemiology of Rospotrebnadzor, Moscow). Results. 11.1% of the tested samples showed positive results;the rhinovirus prevailed (7.32%), while SARS-CoV-2 was detected in 1.66%. In autumn, the proportion of SARS-CoV-2 infected cases increased from 0.49% to 4.02% (p < 0.001). The SARS-CoV-2 RNA concentration was up to 1010 copies/mL. Conclusions. Differences in the prevalence of SARS-CoV-2 and rhinovirus among the age groups and over time were found and analyzed. Using of medical masks reduced the risk of infection with respiratory viruses and with SARS-CoV-2 by 51% and 34%, respectively. In case of prolonged exposure to a COVID-19 patient, healthy people must use a respirator for more effective protection. The individuals whose work was associated with a high level of social contacts were infected more rarely than other individuals in the same age group (p = 0.001);this fact supports the importance of anti-epidemic measures and commitment to their adherence by people whose profession entails frequent social contacts. © 2021, Central Research Institute for Epidemiology. All rights reserved.