The city of Wuhan in China, where the new coronavirus outbreak originated, conducted 222,675 nucleic acid tests on May 16, the local health authority said on Sunday, nearly double the number from a day earlier. Wuhan kicked off a campaign on May 14 to look for asymptomatic carriers after confirming last weekend its first cluster of Covid-19 infections since its release from a virtual lockdown on April 8. The number of tests carried out on May 16 in the city of 11 million residents was also the highest since the Wuhan Municipal Health Commission started publishing the data on February 21. Wuhan is conducting the tests on a voluntary basis. Residents who were previously tested do not need to participate in the campaign. Those who test positive now will be notified as soon as possible. No confirmed cases with symptoms were identified between May 14 and 16, although 28 new asymptomatic carriers were found, according to daily reports published by the Wuhan health authority.