By Fayçal Benhassain | July 28, 2021 | 8:57pm EDT A protestor’s placard makes the point that there are people with both pro- and anti-vaccination views who are united in opposition against the government’s ‘heath pass’ mandate. (Photo by Clement Mahoudeau/AFP via Getty Images) Paris (CNSNews.com) – Some social media stars in France claim to have been approached by a mysterious marketing agency and asked to use their platforms to denigrate the Pfizer COVID-19 vaccine. Léo Grasset, whose science-focused YouTube channel has 1.2 million followers, is one of those who say a marketing agency approached him last spring about posting messages for a fee – for an anonymous client – calling into question the safety and efficacy of the vaccine.