Purpose. To assess epidemiological situation of three co-infections: HIV, CVH and tuberculosis in Vologda region in comparison with neighboring territories of Northwest region.Materials and methods. The data of epidemiological study of the area of HIV infection, reports on «Causes of mortality of HIVinfected », data of statistic surveys: form No. 61 «Data on HIV-infected», form No. 33 «Data on infected with tuberculosis», form No. 8 «Data on infected with active tuberculosis», form No. 1 «Personal record of patient suffered from tuberculosis coinfected with HIV-infection» in Vologda region and some of its districts as well as materials of Northwestern Federal District within the Regional HIV were studied.Results and discussion. Within the territory of Vologda region, earlier marked out tendency to increasing and spread of HIVinfection as well as tendency to reducing the disease burden of tuberculosis and hepatitis C virus still persist. This tendency is typical for northwest Russia and some of its territories. Co-morbidity is common for pair combination of infections and is less common for three infections in one person. Severe forms of HIV-infection in the course of clinical manifestations in combination with tuberculosis and hepatitis define a high rate of morbidity and mortality. Revealed epidemic regularities of the last years are concurrent with cross-border regions in the East and South from the Northwest.

The purpose statement is to assess the course of the COVID-19 pandemic and its impact on the epidemics of HIV infection, viral hepatitis C (HCV), tuberculosis, influenza, and acute respiratory infections in the North-Western Federal District (NWFD) of the Russian Federation during two years of spreading COVID-19 from the standpoint of the possible formation of syndemia or interference between pathogens.Materials and methods. Data collection on HIV infection and HCV was carried out by Pasteur Research Institute of Epidemiology and Microbiology at St. Petersburg Medical Information and Analytical Center using data from federal state statistical observation forms and our own research materials. The indicators of excess mortality from all causes for 2020 in the Northwestern Federal District (NWFD) and in the Russian Federation were analyzed according to the data of the Federal State Statistics Service (ROSSTAT). The results of epidemiological surveillance of HIV infection, viral hepatitis C (HCV), and tuberculosis in the Russian Federation and in the NWED in 2020 and 2021 in comparison with previous years are summarized. Studies of influenza and SARS were carried out by Smorodintsev Research Institute of Influenza and Gamaleya National Research Center for Epidemiology and Microbiology in cooperation with regional support bases. PCR detection of ARVI pathogens was carried out.Results and discussion. An analysis of epidemic indicators across the territories of the Northwestern Federal District of the Russian Federation made it possible to identify the following features: heterogeneity of the incidence of COVID-19 in the population in terms of time and intensity; the prevalence of morbidity in the metropolis (St. Petersburg) and industrial northern regions (the republics of Karelia and Komi). In a comparative aspect, the NWFD belongs to regions with high morbidity and mortality in the Russian Federation. St. Petersburg (378 deaths per 100,000 people in 2021) ranks second after Moscow. In turn, the Vologda, Murmansk, and Arkhangelsk regions, as well as the Komi Republic are among the top ten of the most affected subjects of the Russian Federation in the country. In terms of mortality, St. Petersburg was significantly ahead of all other subjects of the Russian Federation and the national average, which had several probable reasons. The first and second years of the pandemic did not reveal significant changes in epidemic rates of morbidity and mortality from other socially significant infections — HIV, HCV, and tuberculosis at the population level characteristic interference of viruses, where SARS-CoV-2 took the place of interfering, and influenza and SARS pretending or interfering pathogens. It took several months until the beginning of winter 2020 to crowd out seasonal respiratory infections by SARS-CoV-2. Then SARS-CoV-2 tightly captured the epidemic space, leaving no room for traditional respiratory infections, which accounted for less than 5% in early 2022.Conclusion. The COVID-19 epidemic had pronounced developmental features with higher morbidity and mortality in the metropolis and other industrial centers. The pandemic did not significantly affect the patterns of the epidemic course of HIV, HCV, and tuberculosis, which rejected the presence of a syndemic between these pathogens. Interference with respiratory infections — influenza and SARS — was revealed with a clear predominance of SARS-CoV-2.

Pathological conditions of various natures are capable of mutual aggravation, significantly affecting the overall burden of the disease, its manifestations and severity. This analytical review is devoted to the interaction between pathogens of socially significant infections human immunodeficiency viruses (HIV), hepatitis C, Mycobacterium tuberculosis and SARS-CoV-2. Foreign and own data covering the issues of syndemia and interference of pathogens are presented. The results of epidemiological analysis in the North-Western Federal District (NWFD) are presented, which demonstrated the absence of a significant impact of the pandemic caused by a new coronavirus infection (COVID-19) on the epidemic incidence of HIV, viral hepatitis C or tuberculosis at the population level, which may be due to various mechanisms of transmission of infections and the required infectious dose of the pathogen. The absence of a negative effect of COVID-19 on mortality rates in HIV infection, viral hepatitis C and tuberculosis in the territories of the NWFD was noted. Special attention is paid to the clinical picture of the combined course of HIV infection, tuberculosis and COVID-19. The data are demonstrated, which allow us to conclude that the worst prognosis and risk of death are patients in the progressive stage of the disease, which is characterized by the presence of opportunistic infections, especially AIDS-indicator conditions, with disseminated tuberculosis and in the cirrhotic stage of viral hepatitis. The significance of severe manifestations of infectious pathology in cases of deterioration of the prognosis of COVID-19 is shown. Based on the experience of two years of the pandemic, the problems contributing to the syndrome of new coronavirus infection and other conditions, as well as the causes of high mortality from COVID-19, which include: limited resources for non-infectious areas of medical care; insufficient funding for planned and high-tech care; a decrease in the volume of primary diagnosis and detection of infectious and non-infectious pathology; delayed and limited research in areas; distraction of specialists from preventive and dispensary work outside of infectious pathology; shortage of medicines and consumables; social instability and deterioration of the well-being of the population, characteristic of pandemics. The role of a personalized approach to patients with concomitant somatic and infectious diseases as a preventive measure for the severe course and complications of COVID-19 is determined.

The analytical review, based on the analysis of literature and own materials, outlines the features of the interaction of a new coronavirus infection (COVID-19) and acute respiratory diseases. Particular attention is paid to the combined course of SARS-CoV-2 and the influenza virus, a comparative characteristic of the severity of the clinical picture. An assessment of the epidemic situation against the background of the COVID-19 pandemic in foreign countries and the Russian Federation made it possible to establish the presence of the phenomenon of SARS-CoV-2 interference with other viral respiratory agents, based on the facts of a sharp suppression of the circulation of influenza viruses, respiratory syncytial virus (RSV) and other pathogens of acute respiratory viral infections (ARVI) during the period of active spread of pandemic coronavirus. The results obtained confirm the need to ensure effective surveillance and additional diagnostic capabilities for monitoring SARS, which can significantly affect the decision-making on appropriate preventive measures and clinical management of relevant diseases.

The pandemic of the newly coronavirus infection COVID-19 was the test primarily for scientists, experts in epidemiology, infectiology and other fields of medicine participating in addressing the issues of organization and delivery of care, forming up the whole ideology of public health in new conditions. The lecture presents the complex analysis of development of the epidemiologic process, concerning a review of last epidemics, regional features, forecast and modelling approaches, the observers will be able to evaluate demographic, social and medical aspects of evolution. The emphasis is made on the consequences of the transferred infection that directly affect human health, a brief analysis of the clinical manifestations of post-covid syndrome and its expected impact on people, the functioning of all levels of health care, including rehabilitation. The key role of vaccination as the main method of population immunity, prevention of SARS-CoV-2 infection, the development of severe and complicated forms of the disease, as well as domestic manufacturers and manufacturers of several safe and highly effective vaccines has been determined. The article is intended for a wide range of medical professionals, healthcare organizers, government officials and other interested parties.