(Yicai Global) May 12 -- Wuhan, the city that was at the epicenter of China’s novel coronavirus outbreak, will test millions of its residents over the next 10 days after a new cluster of Covid-19 cases emerged.

Wuhan will carry out viral nucleic acid tests, or NATS, on its entire population, according to an emergency notice the local government issued yesterday. Wuhan's health commission reported one new confirmed case on May 10 and another five yesterday, all from within the same community.

The city had a population of more than 14 million at the end of last year, with 9 million registered residents and 5 million migrants, the most recent statistics show. As more than 1 million have had NATS tests already, at least a further 13 million need to be checked.

The new cluster suggests the previous scope of testing was insufficient, a person familiar with the city’s epidemic prevention and control work told Yicai Global. Expanding it is essential to effectively prevent a resurgence of the virus, he added.

City districts must detail their screening implementation plans, including confirming their population base, organization methods and schedules, per the notice. The NATs will check both the districts' permanent and migrant residents, prioritizing the coverage of key areas, including established and densely populated residential areas and those where migrants congregate, with related costs paid from public funds, the city said.

The six new reported cases derive from earlier community infections in the residential area, which has had 20 confirmed cases, according to an official bulletin. This indicated the neighborhood had not been thoroughly disinfected, thus producing a correspondingly higher risk of community infection.

Wuhan is also requiring all teachers, medics, those working in public places and in public transport to undergo NATs before returning to their jobs.

Editors: Dou Shicong, Ben Armour