Resumen
In this work, mathematical modelling of the dynamics of coronavirus COVID-19 is performed for the following countries: the USA, Germany, the UK and the Russian Federation. Cases of COVID-19 virus have been detected in nearly 200 countries. On February 11, 2020, the World Health Organization decided to officially name the virus SARSCoV-2, and the disease caused by this virus - COVID-19 On March 11, WHO Director-General Tedros Gebreyesus announced that the spread of coronavirus infection COVID-19 ?could be described as a pandemic.? Viral incubation period of this virus is quite long, it ranges from 1 to 14 days. The danger of a new disease also lies in the fact that it is easily confused with a common cold or flu. Therefore, the spread of coronavirus COVID-19 is a serious threat for international health and economics. A mathematical description of the dynamics of virus allows to study the nature of the disease thoughtfully, to analyze statistical and model data, to make hypotheses concerning the future dynamics of coronavirus and to evaluate the effectiveness of the measures undertaken. For mathematical modelling of coronavirus COVID-19, the authors use a modified system of differential equations constructed according to the SIR compartmental model. The optimal values of the model parameters, that describe the statistical data precisely, were found. The analysis of the current situation of the COVID-19 coronavirus epidemic in each considering country was made, which led to the efficiency mark of the existing measures to struggle against the virus in the USA, Germany, the UK and the Russian Federation.