Beijing is one of the major Chinese cities that has tightened Covid restrictions as the country struggles to contain a nationwide outbreak.
The city of Guangzhou closed in-person classes at elementary and middle schools on Monday. The measures will be in place for at least a week.
Locals should not leave the city unless they need to, and will need a negative virus test within the last 48 hours to do so.
There were 27 new Covid cases in Guangzhou on Sunday, including 9 without symptoms. The National Health Commission reported that there were 11 cases a day earlier.
The combined number of cases for Sunday was a record high. There were 1,006 cases with symptoms on Saturday.
Most of mainland China's new Covid cases are in the southeastern metropolis. Most people have to stay in their apartments and get food by delivery after a two-part shutdown was originally supposed to end.
The elementary and middle schools were moved to online learning a month ago. The two-stage lockdown began in the name of mass virus testing.
The 11 districts of Guangzhou began another round of testing last week. The expo center is being turned into a makeshift hospital, according to the city.
The worst Covid outbreak on the mainland since the first phase of the epidemic in early 2020 was caused by the highly transmissible omicron variant.
Electric vehicle company Nio announced Saturday that it was suspending production and delaying delivery of its cars because of the Covid issue.
A Morgan Stanley survey found that at the start of this month, about 31% of Chinese people were worried they wouldn't be able to pay debt or rent.
The survey found that there was a slight increase in the number of people who were worried about job losses.
Morgan Stanley analysts don't expect significant changes to China's zero-covid policy until after October or November. The analysts lowered their annual GDP forecast to 4.6% on March 31.
Citigroup analysts raised their China GDP forecast to 5.0% from 4.7% on the expectation that Covid would result in more government spending.
Jilin, the home of many automobile factories, has started to see a leveling out after a spike in Covid cases. The number of new Covid cases in Jilin has fallen from over a thousand a day to several hundred a day.
There were no new locally transmitted cases in Beijing on Sunday. 100 new cases were reported by the province of Hebei.
There were less than 10 new cases with symptoms in the major cities across the country on Sunday.