(CNN)Shanghai's biggest international airport momentarily descended into chaos Sunday night, after authorities ordered a mass testing drive in response to a small outbreak of Covid-19 linked to several cargo handlers.
Shanghai airport momentarily descends into chaos after workers test positive for Covid-19
Since the beginning of November, seven cargo workers and their close contacts at the Shanghai Pudong International Airport have been diagnosed as confirmed coronavirus cases, including two reported on Sunday.
In a bid to contain the cluster, authorities ordered all cargo staff at the airport to undergo coronavirus tests overnight and set up a temporary testing site on the second floor of a parking garage, according to a statement from the Shanghai government.
Photos and videos circulating on Chinese social media show hundreds of people packed closely together inside the garage -- the opposite of social distancing -- with a line of people in hazmat suits trying to hold back crowds pushing forward.
But the chaos appeared to have calmed before midnight, when the airport police posted photos on Weibo showing workers lining up orderly for the tests.
As of Monday morning, 17,719 samples had been collected. Of the 11,544 samples that have been tested, all received negative results, officials said at a news conference.
While the initial chaos has drawn criticism on Chinese social media, the swift, drastic response over just a few cases highlights the length the Chinese government is willing to go to in order to stamp out any resurgence of the virus.
China's zero-tolerance approach is in stark contrast to the United States, which is struggling to cope with its largest wave of infections since the pandemic began. Contact tracing seems almost impossible, with daily new cases above 100,000 for three straight weeks.
On Saturday, the US caseload surpassed 12 million -- an increase of more than 1 million cases in less than a week. On the same day, US President Donald Trump skipped a special side-conference focused on the pandemic during his final Group of 20 summit.
Trump was spotted at his golf course outside of Washington, DC, while world leaders including French President Emmanuel Macron, German Chancellor Angela Merkel, and South Korean President Moon Jae-in discussed global responses to the virus and how to improve pandemic preparedness.
In China, several cities have reported new coronavirus cases over the past week -- and all have been met with immediate action from authorities, from extensive testing and contact tracing to partial lockdowns.
In the port city of Tianjin, some 600 miles (965 kilometers) from Shanghai, authorities are testing 2.6 million residents in one district after reporting five locally transmitted cases on Friday, the Tianjin Health Commission said in a statement.
The mass testing, which started on Saturday, will cover all residents living in the Binhai New Area district, and is expected to be completed in three days.
As of Sunday evening, Tianjin has received more than 2.25 million test samples, of which over 1 million have come back negative, the health commission said.
The more targeted approach -- focusing on one district instead of the entire city of 15 million people -- differs from the city-wide testing drives adopted by large cities such as Wuhan and Qingdao during earlier local outbreaks.
Smaller cities, however, appear intent on testing every resident. Manzhouli, a major land port on the Chinese border with Russia, announced plans to test the whole city in three days after two local infections were reported Saturday. According to the Global Times, a state-run tabloid, a total of 300,000 residents will be tested.
Manzhouli's main train station has suspended operations, while its airport has halted all transfer flights to the regional capital of Hohhot. Schools are su