BEIJING—China reported 76 new COVID-19 cases on July 25, the highest daily total since January amid a surge of local infections in the eastern city of Nanjing, which started a second round of mass testing and banned taxis from leaving to curb the outbreak. China has taken a strict approach to COVID-19 infections, mandating testing for large swathes of its population and tracing the contacts of any positive cases. Local infections accounted for 40 of the new cases, compared with only five a day earlier, the National Health Commission said in a statement on Monday. Thirty-nine of the local cases were reported in the eastern province of Jiangsu, where Nanjing is the capital, and one in the northeastern province of Liaoning, it said. Of the 39 cases, 38 were detected in Nanjing, and one in Suqian city, the provincial government said on its website. As of the end of July …