Correlation between PCR Examination Rate among the Population and the Containment of Pandemic of COVID-19

We investigated the relation between PCR examination rate among population and the success of containment of COVID-19 for each country. Although there was moderate correlation, multiple regression revealed that the success of containment was solely explained by Gross Domestic Product per capita (GDP), which may well be related to the strict compliance to social distancing. Close inspection of individual countries supported this hypothesis. The social distancing must be the largest factor to achieve containment, and the contribution of broad PCR tests is small.

Estimation of the true infection rate and infection fatality rate of COVID-19 in the whole population of each country

The True Infection Rate (TIR) in the whole population of each country and the Infection Fatality Rate (IFR) for coronavirus disease 2019 (COVID-19) are unknown. We devised a simple method to infer TIR and IFR based on the open data. The estimated TIR was compared with local antibody surveys. Estimated IFR took on a wide range of values up to 10%. The importance of the attenuation of the viral virulence is emphasized. Coronavirus disease 2019 (COVID-19) pandemic is a worldwide peril. The True Infection Rate (TIR) of COVID-19 in the whole population of each country and the Infection Fatality Rate (IFR) would be important parameters for guiding the strategy of public health, although they are unknown yet. We devised a simple method to infer TIR and IFR based on the open data.