During the current COVID-19 pandemic, a specific form of the disease called "Long Covid" was the subject of debates and contradictory - even conflicting - positions of the stakeholders, until its institutional and public recognition in 2022. The objectives of this study are : (1) analyzing the modalities of construction and progressive visibility of the category "Long Covid" in the media public sphere and in Twitter;(2) To propose a methodology based on topic modeling and NLP tools to conduct a comparative analysis between newspapers and Twitter coverage.