The number of new infections in the U.S. increased sharply and the death toll hovered just below 200,000, as some guidelines and practices for stopping the disease’s spread have been called into question. Some 52,000 new coronavirus cases were reported in the U.S. on Monday, according to data compiled by Johns Hopkins University, the highest single-day increase since Aug. 14. The U.S. logged 36,695 new cases on Sunday, Johns Hopkins reported. …