Modeling the COVID-19 outbreaks and the effectiveness of the containment measures adopted across countries

Edward De Brouwer; Daniele Raimondi; Yves Moreau

In an attempt to address the under reporting of cases, we computed a reasonable estimate of the actual number of COVID-19 cases in Italy on March 12, 2020. To do so we relied on the fatality rate (CFR) of the disease and the age distribution of the cases in South Korea, which adopted an extensive testing strategy to face the COVID-19 crisis, administering one test every 142 citizens. Since South Korea has tested a very large part of its population with no evident biases, we considered this to be the most reliable data when it comes to reporting the actual numbers and age group of infected individuals. South Korea shows indeed a Pearson correlation coefficient between the number of cases detected among 10-yrs age bins and its demographic structure of r = 0.69 (p-value= 0.039), while Italy has an r = 0.21 (p-value= 0.591), suggesting a much more skewed testing. Our estimation is based on three other assumptions. First, we assume that the disease propagated similarly in South Korea and Italy over the different age bins. Second, we assume that South Korean and Italian healthcare have similar standards, thus suggesting a comparable fatality rate once the testing bias is addressed. Third, we assume that the healthcare system in Italy (e.g., the availability of ICU beds) has not reached saturation, and to satisfy this condition we indeed chose to perform this estimation for March 12, 2020, as lockdown measures in Italy appear to be the result of the healthcare system rapidly approaching saturation. We first adjusted the South Korean number of cases by age group with respect to the demographic structure of the Italian population. As reported on Figure 5 (green bars), the age of confirmed patients is heavily skewed towards older individuals in Italy, while it is more consistent with the demographic structure in the South Korean data. We argue that the skewness of the Italian cases towards older age groups results from the fact that on the February 26, 2020 on the Italian . CC-BY-NC 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.