|A resident takes nucleic acid test at a testing site in Dongxihu District in Wuhan, central China's Hubei Province, May 15, 2020. Xinhua-Yonhap|
Health workers screened about 10 million people in Wuhan between May 15 and Monday, identifying 300 asymptomatic cases but no symptomatic case, the Hubei government said.
Wuhan had previously reported one symptomatic case, a patient identified on May 18 and initially categorised as asymptomatic.
Wuhan deputy mayor Hu Yabo said the tests cost about 900 million yuan (US$126 million) and all expenses were covered by the government.
Hu said some of the samples were tested on their own while others were screened in batches.
The first type cost 106 yuan per person, while the second was less than half that amount per person, Hu said, without specifying how many samples were mixed.
China Business Network reported last month that laboratory workers mixed 10 samples together to reduce the workload. If the test was positive for the coronavirus, a second round of tests on the 10 people sampled would be carried out.
"We have reassured people in Wuhan and around the country via this testing. This shows the [Communist] Party's ruling philosophy of putting the people first will definitely help the city's economy and society get back to normal," he said.
"This expenditure was totally worthwhile."
Wuhan, the first epicentre of the coronavirus, has reported 50,340 cases of the disease Covid-19, including 3,869 deaths, since December.
The city imposed an unprecedented lockdown from January 23 to April 8, confining most of its residents to their homes.
The municipal government announced in mid-May that it would test all its residents after a cluster of new community cases was reported earlier that month.
The cases were the first in the city since its last local patient was reported on April 3.