School mask mandates in the U.S. reduced coronavirus transmission
Mandatory masking lowered transmission of the delta variant by 72 percent
![kindergartners in a classroom, wearing masks](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2022/03/031422_ag_masking-schools_feat.jpg?fit=1030%2C580&ssl=1)
Kindergarten students at Stanley Mosk Elementary School in Los Angeles wear masks while in class on March 11.
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