BEIJING/SHANGHAI—China, on July 20, reported the highest daily tally of new confirmed COVID-19 cases since January, driven by a surge in imported infections in Yunnan province, where cases are spilling over from an “alarming spike” in neighbouring Myanmar. Mainland China recorded 65 new confirmed cases for July 19, compared with 31 a day earlier, the National Health Commission said in a statement. That was the highest count since Jan. 30, when 92 new cases were reported. The United Nations has said it is stepping up efforts to fight an “alarming spike” in infections in military-run Myanmar. The country registered a record 281 COVID-19 deaths on Monday, and 5,189 new infections, state-run MRTV Television reported. The current bout of cases in Yunnan started on July 4, and has been concentrated in Ruili and Longchuan, two small cities on China’s border with Myanmar. Ruili, battling its fourth outbreak since the pandemic started, …