Ahead of the schools opening on September 1, volunteers in east China's Anhui Province are disinfecting campuses. /CFP

A total of 16 volunteers from Bozhou City's administration were seen wearing hazmat suits to disinfect academic buildings and a soccer field of a middle school. /CFP

According to the National Health Commission, the Chinese mainland recorded 21 new confirmed COVID-19 cases on Sunday while there was no new locally transmitted case. /CFP