COVID-19 Pandemic: Duration and Epidemiological Forecast

Abstract

The World Health Organization declared COVID-19 a pandemic on March 11, 2020. While in March 2022, i.e. approximately two years later, the global dominance of the phylogenetic variant of SARS-CoV-2 Omicron with its associated milder clinical course of the disease was registered, and therefore an epidemiological forecast was made about the onset of a period of decline in the pandemic.The aim of this work was to determine the duration and possibility of predicting the COVID-19 pandemic based on an epidemiological assessment of its dynamics in the context of the wave-like course, phase nature, and epidemiological significance of the phylogenetic transformations of the pathogen. Materials from a global source on the Internet about daily cases of infection/deaths of COVID-19, the results of phylogenetic studies of the pathogen and their interpretation using the epidemiological method were analyzed. The evaluation of the COVID-19 pandemic dynamics in the world revealed that it is a typical epidemiological variant of pandemics (epidemics) with its characteristic waves that last for months and do not coincide with the annual solar cycles. As of early March 2023, 7 waves were registered, of which the 1st–4th waves are the epidemic phase, caused by the consistent dominance of the Wuhan and Delta strains, the 6th–7th waves are the post-epidemic phase. The waves varied in duration from 4 to 7 months (M – 4.6 months) and in amplitude from 307205 to 4082344 (M – 1331389.14) peak values of the number of the infected and deaths – from 2997 to 20702 (M – 10506), accordingly. The post-epidemic phase was characterized by a steady trend of quantitative decrease in SARS-CoV-2 Omicron in the form of undulating dynamics with steadily decreasing amplitude of the waves of the number of infected people against the background of a sharp decrease in the number of lethal outcomes compared to the epidemic phase. The continuation of this trend is expected in the form of two more waves of small amplitude (8th and 9th) with a total duration of about 10 months; the completion of the postepidemic phase is predicted in the first half of 2024. Data on the phase nature of the pandemic, determined by genomic changes in the pathogen, are necessary to be prepared for future pandemics.