Sharjah24 – AFP: The Chinese megacity of Guangzhou on Thursday cancelled hundreds of flights and began testing 5.6 million people over one suspected Covid case, part of an escalating battle across the country to extinguish the virus.

China is facing its worst outbreak since the peak of the first wave in early 2020, with eastern Shanghai recording dozens of daily deaths and the capital Beijing sealing off whole neighbourhoods where handfuls of cases have been detected.

Under its zero-Covid policy, China has used lockdowns, mass testing and travel restrictions to stamp out infections.

The strategy is under strain, with the highly transmissible Omicron variant punching through health controls.

Rolling virus restrictions -- including a weeks-long lockdown of virtually all of Shanghai's 25 million residents -- have damaged the economy, causing backlogs at the world's busiest container port, a key node in the global supply chain.

On Thursday Guangzhou, a major trade and manufacturing hub in southern China, announced mass testing for almost a third of its near 19 million residents after an "abnormal" test result was detected at its airport, where most flights have been cancelled.

Meanwhile, the tech hub of Hangzhou near Shanghai late on Wednesday ordered 9.4 million downtown residents out of its 12.2 million population to get tested every 48 hours if they want to access public spaces and transportation.

The aim is "that the virus has nowhere to hide or settle", the city government said in a statement, raising fears of further restrictions across a city home to some of China's biggest companies.

China reported 11,367 new infections on Thursday, a small daily tally compared with most major global economies, but enough to rattle authorities in the country where the coronavirus was first detected in late 2019, but that had until recently emerged relatively unscathed by the pandemic.