SHANGHAI, April 14 (Xinhua) -- A total of 322 COVID-19 patients were released from medical observation and left the National Exhibition and Convention Center (NECC), Shanghai's largest makeshift hospital, on Thursday morning, local authorities said. They were the first batch of patients discharged from the NECC since it started admitting COVID-19 mild cases and asymptomatic carriers on April 9, according to the municipal epidemic control office. The convention centre-turned makeshift hospital has a capacity to accommodate more than 50,000 beds. "I was very worried at first, but when I was hospitalized there, I felt assured. The doctors and nurses are friendly and attentive. I am grateful to them," said a recovered patient surnamed Song. Shanghai reported 2,573 confirmed locally transmitted COVID-19 cases and 25,146 local asymptomatic carriers on Wednesday. On the same day, a total of 737 COVID-19 patients were discharged from hospitals across Shanghai, and another 15,406 people were released from medical observation. They returned to their residence in the city for further health monitoring, health officials told a press conference on Thursday. Photo taken on April 12, 2022, shows the interior view of a makeshift hospital converted from the National Exhibition and Convention Center (NECC) in east China's Shanghai. (Xinhua/Ding Ting) Winter Olympic champion Su Yiming eyes on Grand Slam Chinese envoy calls for comprehensive measures to address conflict-related sexual violence No change in transmissibility of Omicron BA.4, BA.5, or Omicron BA.6: WHO