Shanghai's daily COVID-19 infection numbers have gradually declined, amid the ongoing city campaign to achieve zero community transmission, even as the death toll keeps rising.The city reported 16,980 infections on Monday, 13 percent fewer than Sunday, according Sun Xiaodong, deputy director of the Shanghai Center for Disease Control and Prevention.Despite the city's infection rates still fluctuating at a high level, more than 90 percent of new cases were found during lockdown or central quarantine, he told the city's daily COVID-19 press briefing on Tuesday.