China's "zero-Covid" stance has put it at odds with the rest of the world and is exacting a mounting economic toll, but an exit strategy remains elusive as authorities worry about the ability of the healthcare system to cope and adapt to new strains.

Chinese medical experts believed last year that higher vaccination rates would eventually allow China to relax tough rules on movement and testing as infection rates slow elsewhere.

The emergence of the highly transmissible Omicron variant dashed those hopes.

While some analysts have branded China's approach as "unsustainable", many local health experts - and some from overseas - say the country has no choice but to continue given its less developed health system.

Some even argue China's economy could...