The city reported 322 locally transmitted COVID-19 cases, 19,660 local asymptomatic infections, seven imported patients and one imported asymptomatic infection on Wednesday, said the Shanghai Health Commission on Thursday morning.Of all the local infections, 15 confirmed patients were previously asymptomatic infections. Twelve confirmed patients and 19,027 asymptomatic cases were detected during central quarantine, while the rest were found in the screening of high-risk people.322 local casesThe first 12 patients tested positive during central quarantine.