Estimation of COVID-19 cases in france and in different countries: Homogeneisation based on mortality

Dhenain, M.

Every day authorities of different countries provide an estimate of the number of persons affected by Covid-19 and a count of fatality. We propose to use the fatality reported in each country to provide a better estimate (Ct0-estimated) of the number of cases at a given time t0. Ct0-estimated= (Mt0/ Mt-est) ∗ (Mt0/ Mt0-3j)6With Mt0: number of fatalities reported in a country at time t0;Mt0-3j: number of fatalities reported in a country at time t0 minus 3 days;Mt-est: estimated fatality rate. Based on a fatality rate of 2%, we assessed the number of cases Avril 10th 2020 in Belgium, China, France, Germany, Iran, Italy, South Korea, Netherlands, Spain, United Kingdom and USA. This number reached 2,872,097 in France and 924,892 persons in Germany. This work suggests a very strong underestimation of the number of cases of people affected, with a notification index often less than 5%. The proposed formula also makes it possible to evaluate the impact of policies to prevent the spread of epidemic. © 2020 Academie Veterinaire de France. All rights reserved.