BEIJING — China's Covid situation is only getting worse, preventing the country from stamping out the virus and relaxing controls. The daily case count surged to six-month highs over the weekend. Guangzhou indefinitely delayed its auto show that was supposed to kick off next week. And schools in Beijing are waffling over whether to shift classes online, according to social media. As of Monday, China's Covid controls negatively affected 12.2% of national GDP — up from 9.5% a week ago, according to Nomura's model. The Japanese bank said more than one-fifth of China's population was subject to some kind of...