China has not detected such cases so far except in Hong Kong. Its health authority said the country will stick to its current anti-COVID strategy of preventing imported cases and a domestic resurgence, noting that such an approach is also effective against Omicron. "No matter how the virus mutates, it is still the novel coronavirus," said Zhang Wenhong, head of the Center for Infectious Diseases at the Shanghai-based Huashan Hospital of Fudan University.
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All the local clustered cases in the COVID-19 resurgence since mid-October in China originated from overseas. The resurgence has spread to more than 20 provincial-level regions at its peak.

When dealing with these imported Delta variant cases, most regions managed to contain the outbreak within an incubation period of about 14 days. Aiming to contain an outbreak within an incubation period, relevant Chinese agencies have been making full use of the "golden period," the first 24 hours of a discovered case, to find those who were in close contact, isolate potentially infected individuals before the virus spreads, or before the infected person can transmit the virus.
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Immediately after the three cases were reported, authorities there activated an emergency response. The local government ordered epidemiological investigators to arrive at the scene within two hours, complete the core investigations within four hours, and finish the epidemiological reports within 24 hours.