The city reported 31 locally transmitted COVID-19 cases, 865 local asymptomatic infections, eight imported patients and three imported asymptomatic cases on Monday, said the Shanghai Health Commission on Tuesday morning.Of all the local infections, 30 confirmed patients and 749 asymptomatic cases were detected during central quarantine, while the rest were found in the screening of high-risk people.31 local casesThe first 30 patients tested positive during central quarantine.