Epidemic Curves of COVID-19 in the World which are Similar Within but not Across Regions

Abstract

The number of the COVID-19 patients (P), that of the deaths (D) and the case-fatality rate (D/P) were followed daily from 3 January 2020 till 22 December 2023 for countries in Western Pacific, European, American and African regions. The shape of the epidemic curves was similar within but not across the regions. The number of the patients was proportional to the population size and case-fatality rate was around 0.01 for all the countries except African countries where the number of the patients was not correlated with the population size.