[Covid-19 : un pari épidémiologique perdu ?].

COVID-19: A LOST EPIDEMIOLOGICAL BET? For the last two years, the world has been sailing from one epidemic wave to another. From lockdowns to curfews, strategies have changed over time, whether on travel restrictions, mask requirements, or vaccination. The health crisis has never ceased to toss us from one extreme to the other; each step further testing the resilience of our health system and the population's trust in its leaders. By reviewing some key stages of this pandemic crisis, we highlight why the fight against an emerging virus forces us to trials and errors, which must nevertheless be corrected in the light of the knowledge acquired. Therefore, changes in strategy become necessary even if they undermine the confidence of the population; confidence that cannot be maintained without a perfect understanding of this specific context.