BEIJING • China aims to test more than nine million residents of the port city of Qingdao within five days following a minor coronavirus outbreak, the first mass testing in months.
The country where the virus first emerged has largely controlled its outbreak, cutting a stark contrast to many parts of the world still afflicted by rolling lockdowns and high case numbers.
The new cluster snapped a streak of over two months without local transmission.
As of the end of Sunday, mainland China has recorded 85,578 confirmed cases and 4,634 deaths, according to the National Health Commission yesterday.
The city in Shandong province said on Sunday that it found three asymptomatic cases linked to a hospital which treats Covid-19 patients coming from abroad. Expanded testing of hospital patients and staff then found nine more infections - of the total of 12 in the cluster so far, six are asymptomatic.
Five districts will be tested "within three days" and the whole city "within five days", the Qingdao municipal health commission said in a statement yesterday.
But officials did not say exactly how many people would be tested.
China has extensive, quick test capabilities and the health commission said more than 140,000 employees of "medical institutions, newly admitted patients and personnel" have already been tested in Qingdao since the cases were confirmed.
"A single moment of negligence may provide a way in for the virus under the radar, and then it'll cause several domestic cases," said Dr Zhang Wenhong, director of infectious diseases at Shanghai Huashan Hospital, who advises the local government on containment strategy.
"This is the risk we need to raise our response against."
In June, large areas of the capital Beijing were subject to mass tests after the city of more than 20 million detected virus cases linked to a food market.
Still, the new Qingdao cluster is unlikely to interrupt China's progress in moving past Covid-19 as its economy rebounds and life returns to normal for the vast majority of citizens.
A national eight-day holiday period that just ended saw 637 million trips made domestically, 80 per cent of the level from a year ago, reflecting the country's confidence that mass travel with few restrictions will not result in uncontrollable new flareups.
The sources of these resurgences remain largely a mystery, as asymptomatic carriers prevent health experts from being able to map a chain of transmission.
Last month, Qingdao also found two port workers - responsible for unloading frozen seafood - who tested positive in routine checks without showing symptoms.
China has suspended frozen food imports from plants in several countries after detecting the virus on the packaging or surface of imported meat and seafood.
Qingdao officials are now sticking to the same playbook China has used in curbing resurgences after it contained the initial deadly outbreak in Wuhan. Amid mass testing and contact-tracing, all who test positive are isolated and quarantined, regardless of symptoms.
AGENCE FRANCE-PRESSE, BLOOMBERG