Shanghai reported both a record number of new COVID-19 infections and discharged patients on Sunday, marking the most arduous and key stage of the city's fight against the ongoing epidemic.A total of 17 locally transmitted COVID-19 cases, including six former asymptomatic cases later showing symptoms, and 492 local asymptomatic infections, were detected on Saturday, a new daily record since the coronavirus outbreak in 2020.It means the city's ongoing massive screening is "\\;in-time, effective and necessary,"\\; Wu Jinglei, director of Shanghai Health Commission, told a press briefing on Sunday.