COVID-19 deaths in the U.S. are coming down again, hospitalizations are dropping, and new cases per day are about to dip below 100,000 for the first time in two months — all signs that the summer surge is waning. Not wanting to lose momentum, government leaders and employers are looking to strengthen and vaccine requirements. Los Angeles enacted one of the nation’s strictest vaccine mandates Wednesday, a sweeping measure that would require the shots for everyone entering a bar, restaurant, nail salon, gym or Lakers game. New York City and San Francisco have similar rules.