A day after Joe Biden said he would recommend people wear masks for the first 100 days he is in office, the CDC came out with a report urging “universal face mask use.” This is part of new “Guidance for Public Health Strategies to Address High Levels of Community Transmission of SARS-CoV-2 and Related Deaths.”

While CDC Director Robert Redfield has touted masks as “the most important, powerful health tool we have,” this is the strongest guidance yet from the agency. The report states:

Consistent and correct use of face masks is a public health strategy critical to reducing respiratory transmission of SARS-CoV-2, particularly in light of estimates that approximately one half of new infections are transmitted by persons who have no symptoms… Compelling evidence now supports the benefits of cloth face masks for both source control (to protect others) and, to a lesser extent, protection of the wearer.