The central quarantine site at the Shanghai New International Expo Center in the Pudong New Area opened on Thursday night.The site, so far the biggest quarantine venue in Shanghai, will have up to 15,000 beds for people with mild COVID-19 symptoms and asymptomatic infections.Eight medical teams from leading local hospitals like Ruijin Hospital, Shanghai 6th People's Hospital, Shanghai 10th People's Hospital and the Shanghai Yueyang Hospital of Integrated Traditional Chinese and Western Medicine have arrived at the site.