Dr. Stephen Hoge, Moderna's president, says COVID-19 vaccines are 'really effective,' but notes that the Delta variant 'poses a substantial threat to all of the vaccines' and the durability of immunity.
Dr. Stephen Hoge, Moderna's president, says COVID-19 vaccines are 'really effective,' but notes that the Delta variant 'poses a substantial threat to all of the vaccines' and the durability of immunity.
