China locked down an industrial city of nine million people overnight and reported more than 4,000 virus cases on March 22, as the nation’s “zero-Covid” strategy is confronted by an Omicron wave.

Health authorities reported 4,770 new infections across the country, the bulk in the northeastern province of Jilin, as the city of Shenyang in neighbouring Liaoning province was ordered to lock down late on March 21.

China has moved fast in recent weeks to snuff out virus clusters with a pick-and-mix of hyper-local lockdowns, mass testing and citywide closures. It reported two Covid-19 deaths on March 19, the first in over a year.

Shenyang, an industrial base home to factories including carmaker BMW, reported 47 new cases on March 22 as authorities put all housing compounds under “closed management” and barred residents from leaving without a 48-hour negative test result.

Last week Chinese President Xi Jinping stressed the need to “minimise the impact” of the pandemic on China’s economy, but also urged officials to “stick to” the current zero-Covid approach.

But Beijing’s virus playbook has been stretched to the limit by the latest Omicron surge, which has forced authorities to free up hospital beds from mild-symptom patients.

Jilin provincial officials announced March 21 that the first 10,000 doses of Pfizer’s oral Covid drug arrived on March 20, marking the first time Paxlovid has been used in China.

Health officials last week revealed only around half of Chinese aged over 80 have been double-vaccinated, as the spectre of Hong Kong’s dire Covid mortality rates – mainly among the unvaccinated elderly – hangs over Beijing’s decision making.