https://www.reuters.com/article/health-coronavirus-usa-misinformation/u-s-congressman-presses-facebook-amazon-on-efforts-to-curb-vaccine-misinformation-idUSKBN2G51IO >WASHINGTON (Reuters) -U.S. Democratic Representative Adam Schiff called on Facebook Inc and Amazon.com Inc on Thursday to provide a more thorough explanation of their efforts to mitigate the spread of COVID-19 vaccine misinformation.