New report: Based on a study of the number of people with SARS-CoV-2 antibodies in 10 U.S. metro areas in spring 2020, the estimated number of #COVID19 cases in 7 of the 10 areas studied was 10x higher than the number of reported cases. Read more: https://t.co/fz4OgRsHjI. https://t.co/pwYazN2Iq1