Flatten the curve. On a new covid-19 (hit) severity.

Background: During the health crisis of the COVID-19 pandemic, the adagium was to 'flatten the curve'. We investigate how well countries succeeded in this aim by constructing an appropriate severity measure. It is able to distinguish between countries that, e.g., experienced identical overall (excess) mortality rates or attained equal case load peaks over a certain period of time. Concretely, this implies that an identical total number of infections or deaths over a certain period is considered relatively worse if there is a higher and/or more peaks. More classical measures (like the total number or the maximum of cases/deaths) neglect this and are therefore inappropriate to assess the resilience of a health care system nor pandemic policy ex post performance.

Methods & results: We applied our new (hit) severity to a set of 32 countries, and found that the flattening didn't go equally well. The difference in severity is large, with Norway being consistently the least severely hit by the pandemic (using deaths as indicator) during the whole observation period, while Hungary comes out as eventually being hit the hardest in our sample.

Conclusions: Having constructed a (hit) severity measure that enables to differentiate between countries' performances in a sound way, further research should now relate these observed differences to the pre-pandemic health care status and the sanitary measures or restrictions imposed during the pandemic; in order to reveal what measures help the most in what type of health care system and society.