More cities in central China resorted to tough curbs as new coronavirus infections in Henan province rose sharply, with authorities taking urgent action to contain clusters ahead of the Winter Olympics and Lunar New Year peak travel season.
Henan reported 64 domestically transmitted local infections with confirmed symptoms for Wednesday, up from just four a day earlier, official data showed on Thursday.
Although the numbers are tiny compared with many places in the world, and no cases of the highly transmissible Omicron variant have been reported so far in Henan, several cities there imposed new limits on travel or economic activities in response to a rash of new cases.
China's national policy of stamping out clusters quickly as they appear has taken on extra urgency in the run up to the Winter Games, being hosted by Beijing and nearby Hebei starting Feb. 4.
"The international pandemic situation is serious and complex, the virus variant becomes more transmissible, and COVID-19 prevention and control is more difficult," the state planner said on Thursday on the Lunar New Year travel season.
Gushi, a county in Henan of 1 million residents, reported one symptomatic case and one asymptomatic carrier for Wednesday. But that was enough to persuade local officials to stop people from leaving town and dissuade others from coming.
The city of Xuchang required local officials to minimise movement of people as mass testing on its more than 4 million residents was being rolled out between Thursday and Friday. In Yuzhou city, part of Xuchang's conurbation, 1 million residents are already under lockdown.
Several cities, including Hebi and Kaifeng which are yet to report any new infections recently, have shuttered some cultural and entertainment venues.
Although no local infections were reported on Wednesday in Yongji, a city in the northern province of Shanxi, authorities there ordered all its 400,000 residents to remain indoors and businesses and schools to suspend activities on Thursday, after samples taken from a train station turnstile tested positive for the virus.
Mainland China has only announced a handful of Omicron cases from international travellers and at least one locally transmitted infections, but it has intensified efforts to reduce the risk of the variant being brought in from overseas.
Travellers planning to fly to China from the United States, where Omicron is spreading rapidly, must complete a nucleic acid COVID test seven days before departure, and report their body temperature daily for one week, on top of existing requirements, according to notices published on Tuesday on the websites of the Chinese embassy in the U.S. and several consulates.
"Recently the number of COVID-19 confirmed cases arriving in China from the United States has increased rapidly and significantly," those notices said.
The northwestern city of Xian, more than two weeks into a lockdown, reported 63 local symptomatic infections for Wednesday, up from 35 a day earlier but still much lower than the daily case count seen in the last week of December.
All international flights in the Xian Xianyang International Airport were halted from Wednesday, the official Xinhua news agency reported on Thursday. Domestic flights were suspended earlier.
The lockdown has limited residents' normal access to essential daily routine, including seeking medical services at hospitals. Posts about a pregnant woman who lost her baby after waiting outside of a local hospital, bleeding, stirred social media outcry.
Two Xian health officials were given warnings for not doing their job well due to the incident, state media reported on Thursday. The general manager of the hospital was suspended, with a few other staffers removed from their roles.