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.

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.

Background. The COVID-19 pandemic has exposed health problems, but at the same time has become a powerful impetus for the development of new scientific research in the field of epidemiology, clinic of infectious diseases, diagnostics, bioinformatics and digital methods. On the basis of the Central Research Institute of Epidemiology of Rospotrebnadzor, new unique test systems for the detection of SARS-CoV-2 RNA based on real-time PCR based on loop isothermal amplification (IT) technology have been developed, which allows you to examine samples 34 times faster than those developed previously. The Central Research Institute of Epidemiology of Rospotrebnadzor has developed and put into operation the Russian Platform for Aggregation of Information on Virus Genomes (VGARus). The VGARus database contains information about the nucleotide sequences of the SARS-CoV-2 viruses and their mutations, and the SOLAR Integration Platform has been created to quickly transfer the results of PCR studies to all interested citizens of the Russian Federation. Aims to study the manifestations of the epidemic process of COVID-19 and the prevalence of genovariants of the SARS-CoV-2 virus in the Russian Federation. Methods. A retrospective epidemiological analysis of the incidence of COVID-19 was carried out from March 30, 2020 to May 17, 2022 in the Russian Federation. The database was formed on the basis of the materials of the Rospotrebnadzor report form No. 970 Information on cases of infectious diseases in persons with suspected new coronavirus infection, data from the WHO, the domestic information portal Stopkoronavirus.rf and the Yandex DataLens data visualization and analysis service were used, information on SARS-CoV-2 genovariants in the VGARus database. Results. When analyzing the manifestations of the COVID-19 epidemic process in the Russian Federation for 20202022. Two stages have been identified. The first stage was characterized by the rapid spread of the SARS-CoV-2 virus from megacities to other regions of the country and the use of non-specific prevention measures. The beginning of the second was due to the evolution of the SARS-CoV-2 virus and a change in its biological properties, followed by a change in the prevailing genovariants on the territory of the Russian Federation. Conclusion. As a result of the study, it was found that with each subsequent increase in the incidence of COVID-19, there was a decrease in the severity of the course and the proportion of pneumonia in the structure of the clinical forms of the disease.

The ongoing COVID-19 pandemic around the world and in Russia remains a major event of 2020. All over the world, research is being conducted to comprehensively study the patterns and manifestations of the epidemic process. The main quantitative characteristics of SARS-CoV-2 transmission dynamics among the population, based on the data of official monitoring over the current situation, play an important role in the development of the epidemiological surveillance system.The aim of this studyis to explore the peculiarities of age-gender distribution of COVID-19 patients in Moscow.Material and methods. The data related to the epidemiological characteristics of age-gender structure of COVID-19 patients in Moscow between March 19, 2020 and April 15, 2020, at different stages of the epidemic were retrospectively analyzed.Results and discussion.The mean age of COVID-19 patients in Moscow was 46,41±20,58 years. The gender ratio (male/female) among the patients was 52.7/47.3 %, wherein the indicators varied depending upon the age. Male/female ratio in the age group “under 39” stood at 53.7/46.3 %, and “over 40 years of age” – at 39.3/60.7 %. The predominant age range among male cases was 19 to 39 years old – 35.4 %, while among female patients – 40–59 years (36.5 %). The age distribution of patients in Moscow is indicative of the fact that COVID-19 is a disease that primarily affects older age groups. The age structure of all COVID-19 cases during the observation period is characterized by predominance of adult patients over 19 years of age – 92,7 % (92,6–92,8 %), the share of patients aged 40–59 years is 35,7% (35,5–35,9 %). The differences in the age distribution in males and females are as follows: in the male cohort, the age groups 19–39 years old and 40–59 years old prevail – 35.4 % (35.1–35.7 %) and 34.9 % (34.6–35.2 %), respectively. The age group 40–59 years old – 36.5 % (36.3–36.8%) dominates in the female cohort.

The purpose of the study is to analyze patterns demonstrated by the COVID-19 epidemic process in a megacity during the increase, stabilization and reduction in the incidence, and to evaluate the effectiveness of the epidemic prevention measures.Materials and methods. The comprehensive study incorporating epidemiological, molecular genetic and statistical research methods was conducted to analyze the spread of SARS-CoV-2 in Moscow during the COVID- 19 pandemic.Results and discussion. It was found that the exponential growth in COVID-19 cases was prevented due to the most stringent control and restrictive measures deployed in Moscow to break the chains of SARS-CoV-2 transmission and due to people who were very disciplined in complying with the self-isolation rules. The analysis of the dynamics in detection of new COVID-19 cases showed that in a megacity, the impact of social distancing and self-isolation would become apparent only after 3.5 incubation periods, where the maximum length of the period is 14 days. It was discovered that the detection frequency of SARS-CoV-2 RNA in relatively healthy population and its dynamics are important monitoring parameters, especially during the increase and stabilization in the COVID-19 incidence, and are instrumental in predicting the development of the epidemic situation within a range of 1–2 incubation periods (14–28 days). In Moscow, the case fatality rate was 1.73% over the observation period (6/3/2020–23/6/2020).Conclusion. The epidemiological analysis of the COVID-19 situation in Moscow showed certain patterns of the SARS-CoV-2 spread and helped evaluate the effectiveness of the epidemic prevention measures aimed at breaking the routes of transmission of the pathogen.