Проблемы социальной гигиены, здравоохранения и истории медициныПроблемы социальной гигиены, здравоохранения и истории медицины0869-866X2412-2106Joint-Stock Company Chicot95110.32687/0869-866X-2022-30-4-531-536Научная статьяPhase Dynamics of the Covid-19 Pandemic. A Systematic Analysis of 213 Countries and Territories. Report 2TepponeM.mikhail.teppone@gmail.com1512202230453153617082022Copyright © 2022, АО "Шико"2022The study was carried out to evaluate the dynamics of monthly numbers of cases, deaths, tests and case fatality ratio worldwide during three phases of the COVID-19 pandemic.Material and methods: Twenty-three sets of databases, dated the 22nd of each month from January 2020 to November 2021, for 213 countries were collected from the Worldometer website. The number of cases, deaths, tests, case fatality ratio, infection fatality ratio, etc. were counted for various periods of time for each of the 213 countries, then the results related to different periods of time were compared.The analysis of main epidemiological parameters resulted in division of three phases of the global pandemic evolution. The first phase (23.01.20-22.07.20), the second phase (23.07.20-22.01.21) and the third phase (23.01.21-22.07.21) were different in terms of the number of tests performed, new cases and mortality due to COVID-19. By the end of second phase, the worldwide statistics indicated end of the pandemic, but the third phase was characterized by sudden rise in number of new cases and deaths. The most dramatic evolution of epidemic curve occurred in the countries where physicians had successfully confronted COVID-19 during the first two phases of the pandemic. 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