Between 2020 and August 2022, 34.5 million cases of Covid-19 contamination were identified in France (excluding the results of self-tests). More than 150,000 people died, of which almost 126,400 were in hospital. Contact tracing, deployed from May 2020 after the first lockdown, is one of the tools for combating this epidemic. It consisted of contacting by telephone, SMS or email, the people who tested positive so that they could identify the people with whom they had been in contact, and then contacting them to inform them - while preserving the anonymity of the positive individuals - and to give them prevention instructions. Since its introduction, the health insurance organisation has reached more than 32 million people tested positive for Covid-19 and almost 22.7 million contact persons.