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 topic of epidemiologic surveillance is one of the basic concepts in the theory and practice of epidemiologic science. In Russia, generalization of the accumulated factual material and theoretical developments have allowed us to formulate a number of provisions on the nature of the epidemic process. The pandemic of a new coronavirus infection has forced adjustments in all spheres of society, including the activities of the infectious disease epidemiological surveillance system, requiring the development and implementation of innovative solutions. Based on the experience of prompt response to the tasks set by the COVID-19 pandemic, the authors raised the problem of development and implementation of a system of molecular genetic monitoring for pathogens of emerging and re-emerging infections as a priority vector of epidemiological surveillance development. The introduction of modern molecular biological technologies for the identification of pathogens with epidemic potential, taking into account their genetic diversity, into the system of epidemiologic surveillance has been substantiated based on the experience of using platform solutions created by the Central Research Institute of Epidemiology of Rospotrebnadzor. The strategy of genomic epidemiologic surveillance as a powerful tool to ensure readiness for response measures and management of the epidemic process by implementing and adjusting preventive and anti-epidemic measures was developed. The Russian platform for aggregation of information on virus genomes (VGARus) developed at the Central Research Institute of Epidemiology of Rospotrebnadzor as a technological, scientific, organizational and infrastructural base of genomic epidemiological surveillance, acting as an interdepartmental consortium, has been introduced into practice. The efficiency of VGARus was shown to assess the mutational variability of SARS-CoV-2, the influence of evolutionary development of circulating pathogens on the characteristics of the epidemic process, the implementation of operational and retrospective analysis of morbidity and prediction of the spread of genetic variants of pathogens.

Background.The COVID-19 epidemic in the Russian Federation, which began in March 2020, caused serious damage to health of the population and led to severe economic losses. By December 28, 2020, 3 078 035 cases of COVID-19 and 55 265 lethal outcomes were registered in the country. The population of all territorial subjects of the country is involved in the epidemic process of COVID-19. The severe epidemiological situation made it necessary to conduct an analysis to identify the factors that determine the high intensity of the epidemic process, as well as the population groups with the highest risk of SARS-CoV-2 infection. Aims to study the patterns of SARS-CoV-2 spread and the epidemiological features of the initial stage of the COVID-19 pandemic in the Russian Federation in 2020. Methods.An epidemiological analysis of the COVID-19 situation in the Russian Federation was carried out to determine the dynamics of morbidity, the gender proportion and age structure of patients, the proportion of hospitalized patients, the ratio of various forms of infection, the social and professional status of patients. Standard methods of descriptive statistics Microsoft Excel and STATISTICA 12.0 (StatSoft, USA) were used for statistical processing. The mean values were estimated with a 95% confidence interval [95% CI] (the exact Klopper Pearson method). Results.During the observation time (2020), several periods were identified in the dynamics of the new COVID-19 cases detection: the period of importation of SARS-CoV-2 and the increase in morbidity, the period of epidemic decline, the period of autumn growth, the period of sustained high incidence of COVID-19. It was found that people over 70 years of age are the group with the highest risk of infection and a more severe course of COVID-19. The presence of target contingents among social and professional groups of the population, which should include medical workers, retired person, employees of educational institutions, law enforcement agencies, transport, who require special attention and medical and social support, was shown. Conclusions.The analysis showed that the large-scale spread of COVID-19 requires in-depth epidemiological studies and the development of additional disease control measures, taking into account the dynamics of the incidence of this socially significant infection.

Aim. Identification of epidemiological patterns of the SARS-CoV-2 spread among the population of St. Petersburg during the one-year COVID-19 pandemic period.Materials and methods. The performed analysis focused on the dynamics of COVID-19 cases in St. Petersburg from 2/3/2020 to 4/4/2021 and on the gender-age profile of patients. The information about patients (age, gender, type of the disease, hospitalization, social, and occupational status) was obtained from the database containing the materials from statistical data form No. 058/u.Results. After one year, the dynamics of reported cases of COVID-19 in St. Petersburg shows two cycles of seasonal surge (spring and autumn-winter) and 8 epidemic periods. It has been found that there are no gender-age differences among COVID-19 patients, which can be seen from the relatively similar number of cases among men and women per 100,000 people in each age group during specific epidemic periods. The strong association between clinical manifestations of COVID-19 and the patients' age was detected: Severe cases were more frequently diagnosed in patients over 70 years, regardless of their gender identity. Based on the social and occupational status, the people who were most exposed to the COVID-19 epidemic process were retirees and people whose occupation was associated with health and safety of St. Petersburg. Among the COVID-19 patients, retirees accounted for 13.69% (men) and 17.67% (women). The proportion of healthcare workers was 3.67% (men) and 9.41% (women).Conclusion. It has been assumed that COVID-19 tends to be a seasonal disease featuring annual autumn-winter epidemic cycles. The study addressed prospects of preventive vaccination against COVID-19 in Russia and the importance of tracking the complications pathogenetically associated with the acute phase of the disease in the system of epidemiological surveillance.