Impact of the population age, testing and vaccination levels on the numbers of COVID-19 cases and deaths per capita and case fatality risks

Abstract

ABSTRACTThe population, governments and researchers show much less interest in the COVID-19 pandemic. However, many questions still need to be answered: why the much less vaccinated African continent has accumulated 15 times less deaths per capita than Europe? or why in 2023 the global value of the case fatality risk is almost twice higher than in 2022 and the UK figure is four times higher than the global one?The averaged daily numbers of casesDCCand deathDDCper million, case fatality risksDDC/DCCwere calculated for 34 countries and regions with the use of John Hopkins University (JHU) datasets and possible linear and non-linear correlations with the averaged daily numbers of tests per thousandDTC, median age of populationA, and percentages of vaccinationsVCand boostersBCwere investigated. Strong correlations between age andDCCandDDCvalues were revealed. One-year increment in the median age yielded 39.8 increase inDCCvalues and 0.0799 DDC increase in 2022 (in 2023 these figures are 5.8 and 0.0263, respectively). With decreasing of testing levelDTC, the case fatality risk can increase drastically.DCCandDDCvalues increase with increasing the percentages of fully vaccinated people and boosters, which definitely increase for greaterA. After removing the influence of age, no correlations between vaccinations andDCCandDDCvalues were revealed.The presented analysis demonstrates that age is a pivot factor of visible (registered) part of the COVID-19 pandemic dynamics. Much younger Africa has registered less numbers of cases and death per capita due to many unregistered asymptomatic patients. Of great concern is the fact that COVID-19 mortality in 2023 in the UK is still at least 4 times higher than the global value caused by seasonal flu.