China had largely brought the virus outbreak under control through a series of strict lockdowns and mass testing. But another 138 infections were reported by the National Health Commission on Thursday -- the highest single-day tally since March last year.No details were given by health authorities about the latest death, except that it occurred in Hebei province, where the government has placed several cities under lockdown.Authorities last week launched a mass testing drive and closed transport links, schools and shops in Hebei's capital city Shijiazhuang -- the epicentre of the latest outbreak.Neighbouring Xingtai, home to seven million people, has also been locked down since last Friday, as have the five million people of Langfang.