A request for information from the surgeon general’s office demanded that tech platforms send data and analysis on the prevalence of Covid-19 misinformation on their sites, starting with common examples of vaccine misinformation documented by the Centers for Disease Control and Prevention.

The notice asks the companies to submit “exactly how many users saw or may have been exposed to instances of Covid-19 misinformation,” as well as aggregate data on demographics that may have been disproportionately exposed to or affected by the misinformation.

The surgeon general, Dr. Vivek Murthy, also demanded information from the platforms about the major sources of Covid-19 misinformation, including those that engaged in the sale of unproven Covid-19 products, services and treatments.