By BY SHARON LAFRANIERE, SHERYL GAY STOLBERG AND ERICA L. GREEN U.S. https://ift.tt/3k4tjka The new strategies — including encouraging booster shots for most vaccinated Americans — reflect concerns that the Delta variant is erasing progress against the pandemic. New York Times Coronavirus Risks and Safety Concerns, Coronavirus Delta Variant, Masks, Coronavirus (2019-nCoV), Vaccination and Immunization, United States Politics and Government, Nursing Homes, Education (K-12) August 18, 2021 at 11:51PM