https://www.reuters.com/article/us-health-coronavirus-facebook-insight/facebooks-dilemma-how-to-police-claims-about-unproven-covid-19-vaccines-idUSKCN2530I8

Since the World Health Organization declared the novel coronavirus an international health emergency in January, Facebook Inc has removed more than 7 million pieces of content with false claims about the virus that could pose an immediate health risk to people who believe them.